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Wang H, Liao C, Ding K, Zhang L, Wang L. Evaluation the kill rate and mutant selection window of danofloxacin against Actinobacillus pleuropneumoniae in a peristaltic pump model. BMC Vet Res 2024; 20:241. [PMID: 38831324 PMCID: PMC11145865 DOI: 10.1186/s12917-024-04016-9] [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: 03/29/2023] [Accepted: 04/12/2024] [Indexed: 06/05/2024] Open
Abstract
BACKGROUND Actinobacillus pleuropneumoniae is a serious pathogen in pigs. The abundant application of antibiotics has resulted in the gradual emergence of drugresistant bacteria, which has seriously affected treatment of disease. To aid measures to prevent the emergence and spread of drug-resistant bacteria, herein, the kill rate and mutant selection window (MSW) of danofloxacin (DAN) against A. pleuropneumoniae were evaluated. METHODS For the kill rate study, the minimum inhibitory concentration (MIC) was tested using the micro dilution broth method and time-killing curves of DAN against A. pleuropneumoniae grown in tryptic soy broth (TSB) at a series drug concentrations (from 0 to 64 MIC) were constructed. The relationships between the kill rate and drug concentrations were analyzed using a Sigmoid Emax model during different time periods. For the MSW study, the MIC99 (the lowest concentration that inhibited the growth of the bacteria by ≥ 99%) and mutant prevention concentration (MPC) of DAN against A. pleuropneumoniae were measured using the agar plate method. Then, a peristaltic pump infection model was established to simulate the dynamic changes of DAN concentrations in pig lungs. The changes in number and sensitivity of A. pleuropneumoniae were measured. The relationships between pharmacokinetic/pharmacodynamic parameters and the antibacterial effect were analyzed using the Sigmoid Emax model. RESULTS In kill rate study, the MIC of DAN against A. pleuropneumoniae was 0.016 µg/mL. According to the kill rate, DAN exhibited concentration-dependent antibacterial activity against A. pleuropneumoniae. A bactericidal effect was observed when the DAN concentration reached 4-8 MIC. The kill rate increased constantly with the increase in DAN concentration, with a maximum value of 3.23 Log10 colony forming units (CFU)/mL/h during the 0-1 h period. When the drug concentration was in the middle part of the MSW, drugresistant bacteria might be induced. Therefore, the dosage should be avoided to produce a mean value of AUC24h/MIC99 (between 31.29 and 62.59 h. The values of AUC24h/MIC99 to achieve bacteriostatic, bactericidal, and eradication effects were 9.46, 25.14, and > 62.59 h, respectively. CONCLUSION These kill rate and MSW results will provide valuable guidance for the use of DAN to treat A. pleuropneumoniae infections.
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Affiliation(s)
- Hongjuan Wang
- College of Animal Science and Veterinary Medicine, Henan Institute of Science and Technology, Xinxiang, 453003, China
- Institute of Traditional Chinese Veterinary Medicine, College of Veterinary Medicine, Gansu Agricultural University, Lanzhou, 730070, China
| | - Chengshui Liao
- College of Animal Science and Veterinary Medicine, Henan Institute of Science and Technology, Xinxiang, 453003, China
- The Key Lab of Veterinary Biological Products, Henan University of Science and Technology, Luoyang, 471000, China
| | - Ke Ding
- College of Animal Science and Veterinary Medicine, Henan Institute of Science and Technology, Xinxiang, 453003, China
- Laboratory of Functional Microbiology and Animal Health, Henan University of Science and Technology, Luoyang, 471023, China
| | - Longfei Zhang
- College of Animal Science and Veterinary Medicine, Henan Institute of Science and Technology, Xinxiang, 453003, China.
| | - Lei Wang
- College of Animal Science and Veterinary Medicine, Henan Institute of Science and Technology, Xinxiang, 453003, China.
- Institute of Farmland Irrigation, Chinese Academy of Agricultural Sciences, Xinxiang, 453003, China.
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Copeland R, Zhang C, Hammer BK, Yunker PJ. Spatial constraints and stochastic seeding subvert microbial arms race. PLoS Comput Biol 2024; 20:e1011807. [PMID: 38277405 PMCID: PMC10849242 DOI: 10.1371/journal.pcbi.1011807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 02/07/2024] [Accepted: 01/08/2024] [Indexed: 01/28/2024] Open
Abstract
Surface attached communities of microbes grow in a wide variety of environments. Often, the size of these microbial community is constrained by their physical surroundings. However, little is known about how size constraints of a colony impact the outcome of microbial competitions. Here, we use individual-based models to simulate contact killing between two bacterial strains with different killing rates in a wide range of community sizes. We found that community size has a substantial impact on outcomes; in fact, in some competitions the identity of the most fit strain differs in large and small environments. Specifically, when at a numerical disadvantage, the strain with the slow killing rate is more successful in smaller environments than in large environments. The improved performance in small spaces comes from finite size effects; stochastic fluctuations in the initial relative abundance of each strain in small environments lead to dramatically different outcomes. However, when the slow killing strain has a numerical advantage, it performs better in large spaces than in small spaces, where stochastic fluctuations now aid the fast killing strain in small communities. Finally, we experimentally validate these results by confining contact killing strains of Vibrio cholerae in transmission electron microscopy grids. The outcomes of these experiments are consistent with our simulations. When rare, the slow killing strain does better in small environments; when common, the slow killing strain does better in large environments. Together, this work demonstrates that finite size effects can substantially modify antagonistic competitions, suggesting that colony size may, at least in part, subvert the microbial arms race.
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Affiliation(s)
- Raymond Copeland
- School of Physics, Georgia Institute of Technology, Atlanta, Georgia, United States of America
- Interdisciplinary Program in Quantitative Biosciences, Georgia Institute of Technology, Atlanta, Georgia, United States of America
| | - Christopher Zhang
- Interdisciplinary Program in Quantitative Biosciences, Georgia Institute of Technology, Atlanta, Georgia, United States of America
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia, United States of America
| | - Brian K Hammer
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia, United States of America
| | - Peter J Yunker
- School of Physics, Georgia Institute of Technology, Atlanta, Georgia, United States of America
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Song YM, Zhou HY, Wu Y, Wang J, Liu Q, Mei YF. In Vitro Evaluation of the Antibacterial Properties of Tea Tree Oil on Planktonic and Biofilm-Forming Streptococcus mutans. AAPS PharmSciTech 2020; 21:227. [PMID: 32767025 DOI: 10.1208/s12249-020-01753-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Accepted: 07/09/2020] [Indexed: 02/06/2023] Open
Abstract
Streptococcus mutans (S. mutans) is the principal etiologic agent in the occurrence of human dental caries and the formation of biofilms on the surface of teeth. Tea tree oil (TTO) has been demonstrated to exhibit a wide range of pharmacological actions that can effectively inhibit the activity of bacteria. In this context, we evaluated the in vitro antimicrobial effects of TTO on S. mutans both during planktonic growth and in biofilms compared with 0.2% CHX. We determined the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) using the microdilution method, the bacteriostatic rate using an MTT assay, and the antimicrobial time using a time-kill assay. Then, we explored the effects of TTO on acid production and cell integrity. Furthermore, the effects of TTO on the biomass and bacterial activity of S. mutans biofilms were studied. Finally, scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) were used to investigate the structure and activity of biofilms. The MIC and MBC values were 0.125% and 0.25%, and the bacterial inhibition rate was concentration dependent. TTO can effectively inhibit bacterial acid production and destroy the integrity of the cell membrane. Electron micrographs revealed a reduction in bacterial aggregation, inhibited biofilm formation, and reduced biofilm thickness. The effect of TTO was the same as that of 0.2% CHX at a specific concentration. In summary, we suggest that TTO is a potential anticariogenic agent that can be used against S. mutans.
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Generating Robust and Informative Nonclinical In Vitro and In Vivo Bacterial Infection Model Efficacy Data To Support Translation to Humans. Antimicrob Agents Chemother 2019; 63:AAC.02307-18. [PMID: 30833428 PMCID: PMC6496039 DOI: 10.1128/aac.02307-18] [Citation(s) in RCA: 120] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
In June 2017, the National Institute of Allergy and Infectious Diseases, part of the National Institutes of Health, organized a workshop entitled “Pharmacokinetics-Pharmacodynamics (PK/PD) for Development of Therapeutics against Bacterial Pathogens.” The aims were to discuss details of various PK/PD models and identify sound practices for deriving and utilizing PK/PD relationships to design optimal dosage regimens for patients. Workshop participants encompassed individuals from academia, industry, and government, including the United States Food and Drug Administration. In June 2017, the National Institute of Allergy and Infectious Diseases, part of the National Institutes of Health, organized a workshop entitled “Pharmacokinetics-Pharmacodynamics (PK/PD) for Development of Therapeutics against Bacterial Pathogens.” The aims were to discuss details of various PK/PD models and identify sound practices for deriving and utilizing PK/PD relationships to design optimal dosage regimens for patients. Workshop participants encompassed individuals from academia, industry, and government, including the United States Food and Drug Administration. This and the accompanying review on clinical PK/PD summarize the workshop discussions and recommendations. Nonclinical PK/PD models play a critical role in designing human dosage regimens and are essential tools for drug development. These include in vitro and in vivo efficacy models that provide valuable and complementary information for dose selection and translation from the laboratory to human. It is crucial that studies be designed, conducted, and interpreted appropriately. For antibacterial PK/PD, extensive published data and expertise are available. These have been leveraged to develop recommendations, identify common pitfalls, and describe the applications, strengths, and limitations of various nonclinical infection models and translational approaches. Despite these robust tools and published guidance, characterizing nonclinical PK/PD relationships may not be straightforward, especially for a new drug or new class. Antimicrobial PK/PD is an evolving discipline that needs to adapt to future research and development needs. Open communication between academia, pharmaceutical industry, government, and regulatory bodies is essential to share perspectives and collectively solve future challenges.
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Gil D, Grindy S, Muratoglu O, Bedair H, Oral E. Antimicrobial effect of anesthetic-eluting ultra-high molecular weight polyethylene for post-arthroplasty antibacterial prophylaxis. J Orthop Res 2019; 37:981-990. [PMID: 30737817 DOI: 10.1002/jor.24243] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Accepted: 01/29/2019] [Indexed: 02/04/2023]
Abstract
Despite being a relatively safe surgery, total joint replacement is often associated with two major complications-severe post-operative pain and periprosthetic joint infection. Local sustained delivery of therapeutics to the surgical site has a potential to address these complications more effectively than current clinical approaches. Given that several analgesics were shown to possess antibacterial activity, we propose here to use analgesic-loaded ultra-high molecular weight polyethylene (UHMWPE) as a delivery vehicle to provide antimicrobial effect after an arthroplasty. Three commonly used anesthetics, lidocaine, bupivacaine, and ropivacaine, were analyzed in order to reveal the drug with the highest antibacterial activity against methicillin-sensitive Staphylococcus aureus. Having shown highest antibacterial activity in the bacterial susceptibility tests, bupivacaine was chosen to be incorporated into UHMWPE to provide antibacterial properties. Bupivacaine-loaded UHMWPE possessed moderate dose-dependent antimicrobial properties, decreasing the S. aureus proliferation rate by up to 70%. Biofilm formation was also substanitally inhibited during the first 9 h of culture as quantified by bacterial counts and SEM. This proof-of-concept study is first of its kind to demonstrate that analgesic-loaded UHMWPE can be used as part of a multimodal antimicrobial therapy. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res.
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Affiliation(s)
- Dmitry Gil
- Harris Orthopaedic Laboratory, Massachusetts General Hospital, Boston, Massachusetts.,Department of Orthopaedic Surgery, Harvard Medical School, Harvard University, Boston, Massachusetts
| | - Scott Grindy
- Harris Orthopaedic Laboratory, Massachusetts General Hospital, Boston, Massachusetts.,Department of Orthopaedic Surgery, Harvard Medical School, Harvard University, Boston, Massachusetts
| | - Orhun Muratoglu
- Harris Orthopaedic Laboratory, Massachusetts General Hospital, Boston, Massachusetts.,Department of Orthopaedic Surgery, Harvard Medical School, Harvard University, Boston, Massachusetts
| | - Hany Bedair
- Harris Orthopaedic Laboratory, Massachusetts General Hospital, Boston, Massachusetts.,Department of Orthopaedic Surgery, Harvard Medical School, Harvard University, Boston, Massachusetts
| | - Ebru Oral
- Harris Orthopaedic Laboratory, Massachusetts General Hospital, Boston, Massachusetts.,Department of Orthopaedic Surgery, Harvard Medical School, Harvard University, Boston, Massachusetts
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The antimicrobial activities and action-mechanism of tea tree oil against food-borne bacteria in fresh cucumber juice. Microb Pathog 2018; 125:262-271. [DOI: 10.1016/j.micpath.2018.09.036] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Revised: 09/19/2018] [Accepted: 09/24/2018] [Indexed: 11/18/2022]
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Shi C, Che M, Zhang X, Liu Z, Meng R, Bu X, Ye H, Guo N. Antibacterial activity and mode of action of totarol against Staphylococcus aureus in carrot juice. Journal of Food Science and Technology 2018; 55:924-934. [PMID: 29487434 DOI: 10.1007/s13197-017-3000-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Revised: 08/08/2017] [Accepted: 12/18/2017] [Indexed: 11/25/2022]
Abstract
Food contaminated with pathogenic bacteria such as Staphylococcus aureus (S. aureus), represents a serious health risk to human beings. Totarol is an antibacterial novel phenolic diterpenes. In present study, the antibacterial activity of totarol against S. aureus was investigated in a food system. The antibacterial activity of totarol was determined by measuring the zones of inhibition and minimum inhibitory concentrations (MICs). The MICs for S. aureus strains were in the range of 2-4 μg/ml. The probable antibacterial mechanism of totarol was the alteration in cell membranes integrity and permeability, which leading to the leakage of cellular materials. The electric conductivity showed a time- and dose-dependent increasing manner, and we utilized totarol to induce the production of cytoplasmic β-galactosidase in S. aureus. Scanning electron microscopy and transmission electron microscopy analysis further confirmed that S. aureus cell membranes were damaged by totarol. The time-kill assay and detection of the kinetics of S. aureus deactivation in situ indicated that totarol has good preservative activities in a food model. Totarol successfully inhibited S. aureus development in carrot juice, at room temperature (25 °C) and in refrigerator (4 °C) respectively. Our works provided not only additional evidences in support of totarol being regarded as a natural antibacterial food preservative but also fundamental understanding on the mode of antibacterial action. It is necessary to consider that totarol will become a promising antibacterial additive for food preservative.
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Affiliation(s)
- Ce Shi
- 1Department of Food Quality and Safety, College of Food Science and Engineering, Jilin University, 130062 Changchun, People's Republic of China
| | - Meiyao Che
- 1Department of Food Quality and Safety, College of Food Science and Engineering, Jilin University, 130062 Changchun, People's Republic of China
| | - Xiaowei Zhang
- 1Department of Food Quality and Safety, College of Food Science and Engineering, Jilin University, 130062 Changchun, People's Republic of China
| | - Zuojia Liu
- 2State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 130022 Changchun, People's Republic of China
| | - Rizeng Meng
- Jilin Entry-Exit Inspection and Quarantine Bureau, 130062 Changchun, People's Republic of China
| | - Xiujuan Bu
- 1Department of Food Quality and Safety, College of Food Science and Engineering, Jilin University, 130062 Changchun, People's Republic of China
| | - Haiqing Ye
- 1Department of Food Quality and Safety, College of Food Science and Engineering, Jilin University, 130062 Changchun, People's Republic of China
| | - Na Guo
- 1Department of Food Quality and Safety, College of Food Science and Engineering, Jilin University, 130062 Changchun, People's Republic of China
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Shi C, Zhao X, Liu Z, Meng R, Chen X, Guo N. Antimicrobial, antioxidant, and antitumor activity of epsilon-poly-L-lysine and citral, alone or in combination. Food Nutr Res 2016; 60:31891. [PMID: 27312785 PMCID: PMC4911418 DOI: 10.3402/fnr.v60.31891] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2016] [Revised: 05/22/2016] [Accepted: 05/23/2016] [Indexed: 12/24/2022] Open
Abstract
Background Food safety is an important worldwide public health concern, and microbial contamination in foods not only leads to food deterioration and shelf life reduction but also results in economic losses and disease. Objective The main aim of the present study was to evaluate the effect of epsilon-poly-L-lysine (ε-PL) and citral combination against Escherichia coli O157:H7 (E. coli O157:H7) strains. The preliminary antioxidant and antitumor activities were also studied. Design Synergism is a positive interaction created when two compounds combine and exert an inhibitory effect that is greater than the sum of their individual effects. The synergistic antimicrobial effect of ε-PL and citral was studied using the checkerboard method against E. coli O157:H7. The minimal inhibitory concentration, time-kill, and scanning electron microscope assays were used to determine the antimicrobial activity of ε-PL and citral alone or in combination; 2,2-diphenyl-1-picrylhydrazyl-scavenging assay and western blotting were used in antioxidant activity assays; cell viability assay was carried out to finish preliminary antitumor test. Results Minimal inhibitory concentrations of ε-PL and citral resisted to the five E. coli O157:H7 strains were 2–4 µg/mL and 0.5–1 µg/mL, and the fractional inhibitory concentration indices were 0.25–0.375. The results of time-kill assay revealed that a stronger bactericidal effect in a laboratory medium might be exerted in the combination against E. coli O157:H7 than that in a food model. The compounds alone or in combination exhibited a potential 2,2-diphenyl-1-picrylhydrazyl radical–scavenging activity, and the expression of superoxide dismutase 1 and glutathione peroxidase 1 protein increased. The preliminary antitumor activity effect of the combination was better than ε-PL or citral alone. Conclusions These findings indicated that the combination of ε-PL and citral could not only be used as a promising naturally sourced food preservative but also be used in the pharmaceutical industry.
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Affiliation(s)
- Ce Shi
- Department of Food Quality and Safety, Jilin University, Changchun, P. R. China
| | - Xingchen Zhao
- Department of Food Quality and Safety, Jilin University, Changchun, P. R. China
| | - Zonghui Liu
- Department of Food Quality and Safety, Jilin University, Changchun, P. R. China
| | - Rizeng Meng
- Jilin Entry-Exit Inspection And Quarantine Bureau, Changchun, P. R. China
| | - Xiangrong Chen
- Department of Food Quality and Safety, Jilin University, Changchun, P. R. China
| | - Na Guo
- Department of Food Quality and Safety, Jilin University, Changchun, P. R. China;
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Anthelmintic closantel enhances bacterial killing of polymyxin B against multidrug-resistant Acinetobacter baumannii. J Antibiot (Tokyo) 2015; 69:415-21. [PMID: 26669752 PMCID: PMC4911330 DOI: 10.1038/ja.2015.127] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Revised: 10/29/2015] [Accepted: 11/08/2015] [Indexed: 12/14/2022]
Abstract
Polymyxins, an old class of antibiotics, are currently used as the last resort for the treatment of multidrug-resistant (MDR) Acinetobacter baumannii. However, recent pharmacokinetic and pharmacodynamic data indicate that monotherapy can lead to the development of resistance. Novel approaches are urgently needed to preserve and improve the efficacy of this last-line class of antibiotics. This study examined the antimicrobial activity of novel combination of polymyxin B with anthelmintic closantel against A. baumannii. Closantel monotherapy (16 mg l(-1)) was ineffective against most tested A. baumannii isolates. However, closantel at 4-16 mg l(-1) with a clinically achievable concentration of polymyxin B (2 mg l(-1)) successfully inhibited the development of polymyxin resistance in polymyxin-susceptible isolates, and provided synergistic killing against polymyxin-resistant isolates (MIC ⩾4 mg l(-1)). Our findings suggest that the combination of polymyxin B with closantel could be potentially useful for the treatment of MDR, including polymyxin-resistant, A. baumannii infections. The repositioning of non-antibiotic drugs to treat bacterial infections may significantly expedite discovery of new treatment options for bacterial 'superbugs'.
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Abdul Rahim N, Cheah SE, Johnson MD, Yu H, Sidjabat HE, Boyce J, Butler MS, Cooper MA, Fu J, Paterson DL, Nation RL, Bergen PJ, Velkov T, Li J. Synergistic killing of NDM-producing MDR Klebsiella pneumoniae by two 'old' antibiotics-polymyxin B and chloramphenicol. J Antimicrob Chemother 2015; 70:2589-97. [PMID: 26023209 DOI: 10.1093/jac/dkv135] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2015] [Accepted: 04/23/2015] [Indexed: 01/29/2023] Open
Abstract
OBJECTIVES Combination therapy is an important option in the fight against Gram-negative 'superbugs'. This study systematically investigated bacterial killing and the emergence of polymyxin resistance with polymyxin B and chloramphenicol combinations used against New Delhi metallo-β-lactamase (NDM)-producing MDR Klebsiella pneumoniae. METHODS Four NDM-producing K. pneumoniae strains were employed. The presence of genes conferring resistance to chloramphenicol was examined by PCR. Time-kill studies (inocula ∼10(6) cfu/mL) were conducted using various clinically achievable concentrations of each antibiotic (range: polymyxin B, 0.5-2 mg/L; chloramphenicol, 4-32 mg/L), with real-time population analysis profiles documented at baseline and 24 h. The microbiological response was examined using the log change method and pharmacodynamic modelling in conjunction with scanning electron microscopy (SEM). RESULTS Multiple genes coding for efflux pumps involved in chloramphenicol resistance were present in all strains. Polymyxin B monotherapy at all concentrations produced rapid bacterial killing followed by rapid regrowth with the emergence of polymyxin resistance; chloramphenicol monotherapy was largely ineffective. Combination therapy significantly delayed regrowth, with synergy observed in 25 out of 28 cases at both 6 and 24 h; at 24 h, no viable bacterial cells were detected in 15 out of 28 cases with various combinations across all strains. No polymyxin-resistant bacteria were detected with combination therapy. These results were supported by pharmacodynamic modelling. SEM revealed significant morphological changes following treatment with polymyxin B both alone and in combination. CONCLUSIONS The combination of polymyxin B and chloramphenicol used against NDM-producing MDR K. pneumoniae substantially enhanced bacterial killing and suppressed the emergence of polymyxin resistance.
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Affiliation(s)
- Nusaibah Abdul Rahim
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne, Victoria, Australia
| | - Soon-Ee Cheah
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne, Victoria, Australia
| | - Matthew D Johnson
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne, Victoria, Australia
| | - Heidi Yu
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne, Victoria, Australia
| | - Hanna E Sidjabat
- University of Queensland Centre for Clinical Research, Brisbane, Queensland, Australia
| | - John Boyce
- Department of Microbiology, Monash University, Melbourne, Victoria, Australia
| | - Mark S Butler
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
| | - Matthew A Cooper
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland, Australia
| | - Jing Fu
- Department of Mechanical and Aerospace Engineering, Faculty of Engineering, Monash University, Clayton, Victoria, Australia
| | - David L Paterson
- University of Queensland Centre for Clinical Research, Brisbane, Queensland, Australia Pathology Queensland, Royal Brisbane and Women's Hospital Campus, Brisbane, Queensland, Australia
| | - Roger L Nation
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne, Victoria, Australia
| | - Phillip J Bergen
- Centre for Medicine Use and Safety, Monash University, Melbourne, Victoria, Australia
| | - Tony Velkov
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne, Victoria, Australia
| | - Jian Li
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Melbourne, Victoria, Australia
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