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Sun F, Sun Y, Wang Y, Yuan Q, Xiong L, Feng W, Xia P. Role of Penicillin-Binding Protein 1b in the Biofilm Inhibitory Efficacy of Ceftazidime Against Escherichia coli. Curr Microbiol 2022; 79:271. [PMID: 35881255 DOI: 10.1007/s00284-022-02966-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Accepted: 07/05/2022] [Indexed: 11/24/2022]
Abstract
Penicillin-binding proteins (PBPs) play an important role in bacterial biofilm formation and are the targets of β-lactam antibiotics. This study aimed to investigate the effect of the β-lactam antibiotic ceftazidime (CAZ) at subminimal inhibitory concentration (sub-MIC) on the biofilm formation of Escherichia coli by targeting PBPs. In this study, PBP1a (encoded by mrcA), PBP1b (encoded by mrcB) and PBP3 (encoded by ftsI), which have high affinity for CAZ, were deleted from the E. coli strain. The mrcB mutant showed lower adhesion, biofilm formation and swimming motility, whereas the knockout of mrcA or ftsI had no obvious influence on the biofilm-associated indicators mentioned above. After treatment with sub-MIC of CAZ, the adhesion, biofilm formation and swimming motility of the mrcB-mutant strain were not different or were slightly reduced compared with those of the untreated group. However, sub-MIC of CAZ still significantly inhibited these biofilm-associated indicators in mrcA- and ftsI-mutant strains. In addition, consistent with the bacterial motility results, the deletion of the mrcB gene reduced the flagellar numbers and the expression of flagellar structural genes, but flagellum-related indicators in the mrcB-mutant strain treated with CAZ were similar to those in the untreated group. Bioinformatic analysis showed that CAZ binds to Lys287, Lys274, Glu281, and Arg286 in PBP1b. Taken together, these results suggest that CAZ reduced flagellar synthesis and bacterial motility by binding with PBP1b and thereby inhibited the adhesion and biofilm formation of E. coli.
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Affiliation(s)
- Fengjun Sun
- Department of Pharmacy, Southwest Hospital, Third Military Medical University (Army Medical University), No. 30, Gaotanyan Street, Shapingba District, Chongqing, 400038, China
| | - Yixuan Sun
- Department of Pharmacy, Southwest Hospital, Third Military Medical University (Army Medical University), No. 30, Gaotanyan Street, Shapingba District, Chongqing, 400038, China.,Department of Pharmacy, Chongqing Municipal People's Hospital, Chongqing, 400014, China
| | - Yu Wang
- Department of Pharmacy, Southwest Hospital, Third Military Medical University (Army Medical University), No. 30, Gaotanyan Street, Shapingba District, Chongqing, 400038, China
| | - Qian Yuan
- Department of Pharmacy, Southwest Hospital, Third Military Medical University (Army Medical University), No. 30, Gaotanyan Street, Shapingba District, Chongqing, 400038, China
| | - Lirong Xiong
- Department of Pharmacy, Southwest Hospital, Third Military Medical University (Army Medical University), No. 30, Gaotanyan Street, Shapingba District, Chongqing, 400038, China
| | - Wei Feng
- Department of Pharmacy, Southwest Hospital, Third Military Medical University (Army Medical University), No. 30, Gaotanyan Street, Shapingba District, Chongqing, 400038, China.
| | - Peiyuan Xia
- Department of Pharmacy, Southwest Hospital, Third Military Medical University (Army Medical University), No. 30, Gaotanyan Street, Shapingba District, Chongqing, 400038, China.
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Feng W, Zhang L, Yuan Q, Wang Y, Yao P, Xia P, Sun F. Effect of sub-minimal inhibitory concentration ceftazidime on the pathogenicity of uropathogenic Escherichia coli. Microb Pathog 2021; 151:104748. [PMID: 33484810 DOI: 10.1016/j.micpath.2021.104748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 01/04/2021] [Accepted: 01/14/2021] [Indexed: 11/18/2022]
Abstract
Uropathogenic Escherichia coli (UPEC) is the most prevalent causative agent of urinary tract infections (UTIs). The pathogenicity of UPEC relies on the expression of virulence factors which could be regulated by intercellular signal molecules. Our previous study found that sub-minimal inhibitory concentration ceftazidime (sub-MIC CAZ) could inhibit the biofilm formation of E. coli by luxS/AI-2 or indole. Therefore, we speculated that sub-MIC CAZ might affect the pathogenic capacity of UPEC. In this study, the results showed that sub-MIC CAZ could significantly inhibit the adhesion ability, biofilm formation and swimming and swarming motilities of UPEC isolated from recurrent UTI patient. Meanwhile, obvious decreased hemolytic activity and cytotoxicity were observed in CAZ-pretreated UPEC. Furthermore, qRT-PCR results confirmed the downregulating ability of CAZ on the expression of adhesion genes, motility genes, toxin gene and signal molecule synthesis genes, which are important for virulence and biofilm formation of UPEC. Pre-treatment of UPEC with sub-MIC CAZ resulted in the reduced adhesion to human bladder epithelial cell 5637 and the decreased numbers of intracellular bacterial communities in cells. Consistent with the results in vitro, the pretreatment of CAZ resulted in the reduction of UPEC load in the bladder and the less severity of UPEC-induced inflammation compared with control group. The present study results indicated that sub-MIC CAZ could decrease the pathogenicity of UPEC and might be served as an effective antimicrobial agent to combat recurrent UTI caused by UPEC.
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Affiliation(s)
- Wei Feng
- Department of Pharmacy, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China
| | - Lei Zhang
- Department of Pharmacy, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China; Chongqing Healthcare Security Administration, Chongqing, 401120, China
| | - Qian Yuan
- Department of Pharmacy, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China
| | - Yu Wang
- Department of Pharmacy, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China
| | - Pu Yao
- Department of Pharmacy, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China
| | - Peiyuan Xia
- Department of Pharmacy, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China.
| | - Fengjun Sun
- Department of Pharmacy, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China.
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Chadha J. In vitro effects of sub-inhibitory concentrations of amoxicillin on physiological responses and virulence determinants in a commensal strain of Escherichia coli. J Appl Microbiol 2021; 131:682-694. [PMID: 33387370 DOI: 10.1111/jam.14987] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 12/14/2020] [Accepted: 12/26/2020] [Indexed: 02/06/2023]
Abstract
AIMS The goal was to study the effects of sub-minimum inhibitory concentrations (sub-MICs) of amoxicillin (AMX) on various physiological responses and virulence determinants in a commensal strain of Escherichia coli. MATERIALS AND RESULTS The commensal strain was passaged under various sub-MICs of AMX and its effect on bacterial growth, motility, biofilm formation, expression of outer membrane proteins (OMPs) and cell adhesion was analysed. Bacterial growth was diminished at 1/2 and 1/4 MICs of AMX with significant reduction in growth rate. Using crystal violet (CV) assays and quantification of surface polysaccharides we observed strong biofilm formation, together with reduced swimming motility in E. coli at 1/2 MIC of AMX. Differential OMP expression upon AMX sub-MIC exposure coincided with enhanced cell adhesion to HT-29 cells in vitro. The results demonstrated that sub-MICs of AMX can stimulate unpredictable changes in commensal bacterial strains which can be a potent source for the propagation of antibiotic resistance. CONCLUSIONS The study reports that AMX at 1/2 MIC significantly compromised bacterial growth and swimming motility, alongside inducing biofilm formation. This was also accompanied by upregulation of a single OMP which subsequently increased cell adhesion capabilities in E. coli at 1/2 MIC, thereby enhancing its colonization and survival abilities within the gut microsphere. SIGNIFICANCE AND IMPACT OF THE STUDY For the first time, the effects of AMX sub-MICs on a commensal E. coli strain were described. The results corroborate on how antibiotics can act as stimulatory molecules and determine the pathogenicity of commensal bacteria in vivo that can disseminate resistance to other intestinal pathogens or microbes.
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Affiliation(s)
- J Chadha
- Department of Microbiology, University of Delhi South Campus, New Delhi, India
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Zhu C, Zhang M, Tang Q, Yang Q, Li J, He X, Ye Y. Structure and Activity of the Camellia oleifera Sapogenin Derivatives on Growth and Biofilm Inhibition of Staphylococcus aureus and Escherichia coli. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2019; 67:14143-14151. [PMID: 31469956 DOI: 10.1021/acs.jafc.9b03577] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Sapogenin is the main block of Camellia oleifera saponin, which was purified and structurally modified by the C28 acylation reaction to synthesize 19 new derivatives. The growth and biofilm inhibition of Staphylococcus aureus and Escherichia coli was measured to evaluate their antibacterial effects. A three-dimensional quantitative structure-activity relationship (3D-QSAR) assay indicated that the antibacterial activities were significantly enhanced after sapogenin was modified with an aromatic ring or heterocyclic ring and electron-withdrawing substituents at the meta or para position. Among them, the derivative of sapogenin with a 2-mercapto-4-methyl-5-thiazolyl acetyl group obviously destroyed bacterial biofilm and made bacteria lysis. 3D-QSAR provides practical information for the structural design of sapogenin derivatives with strong antibacterial activity, and the C. oleifera sapogenin derivative 28-O-(2-mercapto-4-methyl-5-thiazolyl)-3β,16α,21β,22α-O-tetrahydroxy-oleantel-2-ene-23-aldehyde (S-16) is an effective candidate as an antibacterial agent for the prevention of bacterial resistance against antibiotics.
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Affiliation(s)
- Chunfang Zhu
- Department of Pharmaceutical Engineering, School of Chemistry and Chemical Engineering , South China University of Technology , Guangzhou , Guangdong 510640 , People's Republic of China
| | - Meng Zhang
- Department of Pharmaceutical Engineering, School of Chemistry and Chemical Engineering , South China University of Technology , Guangzhou , Guangdong 510640 , People's Republic of China
| | - Qiaoling Tang
- Department of Pharmaceutical Engineering, School of Chemistry and Chemical Engineering , South China University of Technology , Guangzhou , Guangdong 510640 , People's Republic of China
| | - Qian Yang
- Department of Pharmaceutical Engineering, School of Chemistry and Chemical Engineering , South China University of Technology , Guangzhou , Guangdong 510640 , People's Republic of China
| | - Jing Li
- Department of Pharmaceutical Engineering, School of Chemistry and Chemical Engineering , South China University of Technology , Guangzhou , Guangdong 510640 , People's Republic of China
| | - Xuan He
- Gannan Medical University Collaborative Innovation Center for Gannan Oil-Tea Camellia Industrial Development , Ganzhou , Jiangxi 341000 , People's Republic of China
| | - Yong Ye
- Department of Pharmaceutical Engineering, School of Chemistry and Chemical Engineering , South China University of Technology , Guangzhou , Guangdong 510640 , People's Republic of China
- Gannan Medical University Collaborative Innovation Center for Gannan Oil-Tea Camellia Industrial Development , Ganzhou , Jiangxi 341000 , People's Republic of China
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Zhang J, Ye CZ, Liu ZY, Yang Q, Ye Y. Preparation And Antibacterial Effects Of Carboxymethyl Chitosan-Modified Photo-Responsive Camellia Sapogenin Derivative Cationic Liposomes. Int J Nanomedicine 2019; 14:8611-8626. [PMID: 31802873 PMCID: PMC6830381 DOI: 10.2147/ijn.s218101] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2019] [Accepted: 10/04/2019] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Bacterial resistance to antibiotics is a persistent and intractable problem. The sapogenin isolated from the seeds of Camellia oleifera can inhibit antibiotic-resistant bacteria after structural modification. PURPOSE This study aims to improve sapogenin's antibacterial activity and avoid bacterial resistance based on nano-preparation with photo responsiveness. METHODS The liposome shell material of carboxymethyl chitosan-phosphatidyl ethanolamine (CMC-PE) was prepared using amidation reaction, and photo-responsive cationic (PCC) liposomes containing Camellia sapogenin derivative (CSD) and photosensitizer pheophorbide-a were prepared by film dispersion method. Encapsulation efficiency, drug loading, zeta potential, particle size distribution, morphology and stability of the PCC liposomes were determined by HPLC, particle size analyzer, transmission electron microscopy (TEM) and fluorescence microscopy. Photo-responsive release of CSD in the PCC liposomes was determined by laser (0.5 mW/cm2) at 665 nm. Antibacterial activity of the PCC liposomes with or without irradiation was analyzed by MIC50, MBC, MBIC50, and bacterial morphology to evaluate the antibacterial effects on amoxicillin resistant Escherichia coli and Staphylococcus aureus. RESULTS Size distribution, zeta potential, encapsulation efficiency and drug loading of the PCC liposomes were 189.23 ± 2.12 nm, 18.80 ± 1.57 mV, 83.52 ± 1.53% and 2.83 ± 0.05%, respectively. The PCC liposomes had higher storage stability and gastrointestinal stability, and no obvious hemolytic toxicity to rabbit red blood cells and no cytotoxicity after incubation with Hela cells. The photosensitizer pheophorbide-a was uniformly dispersed in the phospholipid layer of the PCC liposomes and increased the CSD release after irradiation. The PCC liposomes could bind to bacteria and impaired their morphology and structure, and had significant bactericidal effect on amoxicillin resistant E. coli and S. aureus. CONCLUSION The photo-responsive PCC liposomes are efficient antibacterial agents for avoidance of bacterial resistance against antibiotics.
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Affiliation(s)
- Jin Zhang
- Department of Pharmaceutical Engineering, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou510640, People’s Republic of China
| | - Chuan-Zhen Ye
- Department of Pharmaceutical Engineering, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou510640, People’s Republic of China
| | - Ze-Yu Liu
- Department of Pharmaceutical Engineering, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou510640, People’s Republic of China
| | - Qian Yang
- Department of Pharmaceutical Engineering, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou510640, People’s Republic of China
| | - Yong Ye
- Department of Pharmaceutical Engineering, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou510640, People’s Republic of China
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Sun F, Yuan Q, Wang Y, Cheng L, Li X, Feng W, Xia P. Sub-minimum inhibitory concentration ceftazidime inhibits Escherichia coli biofilm formation by influencing the levels of the ibpA gene and extracellular indole. J Chemother 2019; 32:7-14. [PMID: 31631801 DOI: 10.1080/1120009x.2019.1678913] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Escherichia coli is a common pathogen of bacterial biofilm infections. Sub-minimum inhibitory concentration ceftazidime (sub-MIC CAZ) could inhibit the biofilm formation of E. coli. Deletion of the ibpAB genes could increase the extracellular indole concentration of E. coli and then inhibit biofilm formation. Therefore, we speculated that sub-MIC CAZ might inhibit biofilm formation via ibpAB. In this study, the results showed that sub-MIC CAZ could significantly inhibit biofilm formation, swimming motility and the expression of the ibpA gene, while it could increase the expression of tnaA gene and extracellular indole concentration. Knockout of the ibpA gene resulted in a decrease in biofilm formation and swimming motility and an increase in the indole concentration. When treated with sub-MIC CAZ, the tnaA gene expression, indole concentration, biofilm formation and swimming motility of MG1655 ΔibpA were similar to those of the control group. The results indicated that sub-MIC CAZ might inhibit the biofilm formation of E. coli by increasing the extracellular indole concentration and downregulating the ibpA gene.
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Affiliation(s)
- Fengjun Sun
- Department of Pharmacy, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
| | - Qian Yuan
- Department of Pharmacy, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
| | - Yu Wang
- Department of Pharmacy, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
| | - Lin Cheng
- Department of Pharmacy, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
| | - Xiaoyu Li
- Department of Pharmacy, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
| | - Wei Feng
- Department of Pharmacy, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
| | - Peiyuan Xia
- Department of Pharmacy, Southwest Hospital, Third Military Medical University (Army Medical University), Chongqing, China
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Targeted delivery of antibiotics to the infected pulmonary tissues using ROS-responsive nanoparticles. J Nanobiotechnology 2019; 17:103. [PMID: 31581948 PMCID: PMC6777033 DOI: 10.1186/s12951-019-0537-4] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Accepted: 09/24/2019] [Indexed: 01/07/2023] Open
Abstract
Background Immunocompromised individuals and those with lung dysfunction readily acquire pulmonary bacterial infections, which may cause serious diseases and carry a heavy economic burden. Maintaining adequate antibiotic concentrations in the infected tissues is necessary to eradicate resident bacteria. To specifically deliver therapeutics to the infected pulmonary tissues and enable controlled release of payloads at the infection site, a ROS-responsive material, i.e. 4-(hydroxymethyl) phenylboronic acid pinacol ester-modified α-cyclodextrin (Oxi-αCD), was employed to encapsulate moxifloxacin (MXF), generating ROS-responsive MXF-containing nanoparticles (MXF/Oxi-αCD NPs). Results MXF/Oxi-αCD NPs were coated with DSPE-PEG and DSPE-PEG-folic acid, facilitating penetration of the sputum secreted by the infected lung and enabling the active targeting of macrophages in the inflammatory tissues. In vitro drug release experiments indicated that MXF release from Oxi-αCD NPs was accelerated in the presence of 0.5 mM H2O2. In vitro assay with Pseudomonas aeruginosa demonstrated that MXF/Oxi-αCD NPs exhibited higher antibacterial activity than MXF. In vitro cellular study also indicated that folic acid-modified MXF/Oxi-αCD NPs could be effectively internalized by bacteria-infected macrophages, thereby significantly eradicating resident bacteria in macrophages compared to non-targeted MXF/Oxi-αCD NPs. In a mouse model of pulmonary P. aeruginosa infection, folic acid-modified MXF/Oxi-αCD NPs showed better antibacterial efficacy than MXF and non-targeted MXF/Oxi-αCD NPs. Meanwhile, the survival time of mice was prolonged by treatment with targeting MXF/Oxi-αCD NPs. Conclusions Our work provides a strategy to overcome the mucus barrier, control drug release, and improve the targeting capability of NPs for the treatment of pulmonary bacterial infections.
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He J, Jia X, Yang S, Xu X, Sun K, Li C, Yang T, Zhang L. Heteroresistance to carbapenems in invasive Pseudomonas aeruginosa infections. Int J Antimicrob Agents 2017; 51:413-421. [PMID: 29127047 DOI: 10.1016/j.ijantimicag.2017.10.014] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2017] [Revised: 09/14/2017] [Accepted: 10/28/2017] [Indexed: 11/24/2022]
Abstract
Heteroresistance is common in a variety of microbes, however carbapenem heteroresistance among invasive Pseudomonas aeruginosa infections has not been thoroughly characterised to date. The objective of this study was to investigate the mechanisms, molecular epidemiology and risk factors for invasive carbapenem-heteroresistant P. aeruginosa (CHPA) infections between 2011 and 2015 in Chongqing, China. A significant increase in the rates of heteroresistance to imipenem and meropenem was observed during the study period. Mechanistic analysis revealed that efflux system overexpression and decreased OprD could have contributed to carbapenem heteroresistance in P. aeruginosa. It was also observed that all of the subpopulations produced enhanced levels of biofilm compared with their native strains. Moreover, previous carbapenem exposure was identified as a common independent risk factor for imipenem-heteroresistant (IPM-HR) and meropenem-heteroresistant (MEM-HR) isolates, but patients infected with MEM-HR isolates were at higher risk of poor outcomes than those with IPM-HR isolates. Most importantly, there was a remarkable increase in the prescription of carbapenems during the study period, which was demonstrated to correlate significantly with the quarterly increasing prevalence of IPM-HR and MEM-HR isolates, respectively. These findings show the necessity of routine detection of carbapenem-heteroresistant strains and that strict control of carbapenem use is critical to reduce CHPA infections in hospitalised patients.
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Affiliation(s)
- Jianchun He
- Department of Laboratory Medicine, The First Affiliated Hospital of Chongqing Medical University, No. 1 Youyi Road, Yuzhong District, Chongqing 400016, PR China
| | - Xiaojiong Jia
- Department of Laboratory Medicine, The First Affiliated Hospital of Chongqing Medical University, No. 1 Youyi Road, Yuzhong District, Chongqing 400016, PR China
| | - Shuangshuang Yang
- Department of Laboratory Medicine, The First Affiliated Hospital of Chongqing Medical University, No. 1 Youyi Road, Yuzhong District, Chongqing 400016, PR China
| | - Xiuyu Xu
- Department of Laboratory Medicine, The First Affiliated Hospital of Chongqing Medical University, No. 1 Youyi Road, Yuzhong District, Chongqing 400016, PR China
| | - Kunling Sun
- Department of Laboratory Medicine, The First Affiliated Hospital of Chongqing Medical University, No. 1 Youyi Road, Yuzhong District, Chongqing 400016, PR China
| | - Congya Li
- Department of Laboratory Medicine, The First Affiliated Hospital of Chongqing Medical University, No. 1 Youyi Road, Yuzhong District, Chongqing 400016, PR China
| | - Tianxiang Yang
- Department of Laboratory Medicine, The First Affiliated Hospital of Chongqing Medical University, No. 1 Youyi Road, Yuzhong District, Chongqing 400016, PR China
| | - Liping Zhang
- Department of Laboratory Medicine, The First Affiliated Hospital of Chongqing Medical University, No. 1 Youyi Road, Yuzhong District, Chongqing 400016, PR China.
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