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Wang J, Zhang M, Li C, Liu M, Qi Y, Xie X, Zhou C, Ma L. A novel cathelicidin TS-CATH derived from Thamnophis sirtalis combats drug-resistant gram-negative bacteria in vitro and in vivo. Comput Struct Biotechnol J 2024; 23:2388-2406. [PMID: 38882682 PMCID: PMC11176561 DOI: 10.1016/j.csbj.2024.05.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2023] [Revised: 05/08/2024] [Accepted: 05/13/2024] [Indexed: 06/18/2024] Open
Abstract
Antimicrobial peptides are promising therapeutic agents for treating drug-resistant bacterial disease due to their broad-spectrum antimicrobial activity and decreased susceptibility to evolutionary resistance. In this study, three novel cathelicidin antimicrobial peptides were identified from Thamnophis sirtalis, Balaenoptera musculus, and Lipotes vexillifer by protein database mining and sequence alignment and were subsequently named TS-CATH, BM-CATH, and LV-CATH, respectively. All three peptides exhibited satisfactory antibacterial activity and broad antibacterial spectra against clinically isolated E. coli, P. aeruginosa, K. pneumoniae, and A. baumannii in vitro. Among them, TS-CATH displayed the best antimicrobial/bactericidal activity, with a rapid elimination efficiency against the tested drug-resistant gram-negative bacteria within 20 min, and exhibited the lowest cytotoxicity toward mammalian cells. Furthermore, TS-CATH effectively enhanced the survival rate of mice with ceftazidime-resistant E. coli bacteremia and promoted wound healing in meropenem-resistant P. aeruginosa infection. These results were achieved through the eradication of bacterial growth in target organs and wounds, further inhibiting the systemic dissemination of bacteria and the inflammatory response. TS-CATH exhibited direct antimicrobial activity by damaging the inner and outer membranes, resulting in leakage of the bacterial contents at super-MICs. Moreover, TS-CATH disrupted the bacterial respiratory chain, which inhibited ATP synthesis and induced ROS formation, significantly contributing to its antibacterial efficacy at sub-MICs. Overall, TS-CATH has potential for use as an antibacterial agent.
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Affiliation(s)
- Jian Wang
- Institution of all authors: College of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu 211198, China
| | - Meina Zhang
- Institution of all authors: College of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu 211198, China
| | - Chao Li
- Institution of all authors: College of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu 211198, China
| | - Mengyuan Liu
- Institution of all authors: College of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu 211198, China
| | - Yixin Qi
- Institution of all authors: College of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu 211198, China
| | - Xiaolin Xie
- Institution of all authors: College of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu 211198, China
| | - Changlin Zhou
- Institution of all authors: College of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu 211198, China
| | - Lingman Ma
- Institution of all authors: College of Life Science and Technology, China Pharmaceutical University, Nanjing, Jiangsu 211198, China
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2
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Jin S, Mia R, Newton MAA, Cheng H, Gao W, Zheng Y, Dai Z, Zhu J. Nanofiber-reinforced self-healing polysaccharide-based hydrogel dressings for pH discoloration monitoring and treatment of infected wounds. Carbohydr Polym 2024; 339:122209. [PMID: 38823899 DOI: 10.1016/j.carbpol.2024.122209] [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: 02/13/2024] [Revised: 04/23/2024] [Accepted: 04/24/2024] [Indexed: 06/03/2024]
Abstract
The escalating global health concern arises from chronic wounds induced by bacterial infections, posing a significant threat to individuals. Consequently, an imperative exist for the development of hydrogel dressings to facilitate prompt wound monitoring and efficacious wound management. To this end, pH-sensitive bromothymol blue (BTB) and pH-responsive drug tetracycline hydrochloride (TH) were introduced into the polysaccharide-based hydrogel to realize the integration of wound monitoring and controlled treatment. Polysaccharide-based hydrogels were formed via a Schiff base reaction by cross-linking carboxymethyl chitosan (CMCS) on an oxidized sodium alginate (OSA) skeleton. BTB was used as a pH indicator to monitor wound infection through visual color changes visually. TH could be dynamically released through the pH response of the Schiff base bond to provide effective treatment and long-term antibacterial activity for chronically infected wounds. In addition, introducing polylactic acid nanofibers (PLA) enhanced the mechanical properties of hydrogels. The multifunctional hydrogel has excellent mechanical, self-healing, injectable, antibacterial properties and biocompatibility. Furthermore, the multifaceted hydrogel dressing under consideration exhibits noteworthy capabilities in fostering the healing process of chronically infected wounds. Consequently, the research contributes novel perspectives towards the advancement of intelligent and expeditious bacterial infection monitoring and dynamic treatment platforms.
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Affiliation(s)
- Shanshan Jin
- School of Textiles and Fashion, Shanghai University of Engineering Science, Shanghai 201620, China
| | - Rajib Mia
- School of Textiles and Fashion, Shanghai University of Engineering Science, Shanghai 201620, China
| | - Md All Amin Newton
- School of Textiles and Fashion, Shanghai University of Engineering Science, Shanghai 201620, China
| | - Hongju Cheng
- School of Textiles and Fashion, Shanghai University of Engineering Science, Shanghai 201620, China
| | - Weihong Gao
- School of Textiles and Fashion, Shanghai University of Engineering Science, Shanghai 201620, China
| | - Yuansheng Zheng
- School of Textiles and Fashion, Shanghai University of Engineering Science, Shanghai 201620, China
| | - Zijian Dai
- Innovation Center for Textile Science and Technology, Donghua University, Shanghai 200051, China.
| | - Jie Zhu
- School of Textiles and Fashion, Shanghai University of Engineering Science, Shanghai 201620, China.
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Ahmadi TS, Behrouz B, Mousavi Gargari SL. Polyclonal anti-whole cell IgY passive immunotherapy shields against P. aeruginosa-induced acute pneumonia and burn wound infections in murine models. Sci Rep 2024; 14:405. [PMID: 38172232 PMCID: PMC10764880 DOI: 10.1038/s41598-023-50859-x] [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: 06/25/2023] [Accepted: 12/27/2023] [Indexed: 01/05/2024] Open
Abstract
Pseudomonas aeruginosa (PA) is a multidrug-resistant (MDR) opportunistic pathogen causing severe hospital-, and community-acquired infections worldwide. Thus, the development of effective immunotherapy-based treatments is essential to combat the MDR-PA infections. In the current study, we evaluated the protective efficacy of polyclonal avian antibodies raised against inactivated whole cells of the PAO1 strain in murine models of acute pneumonia and burn wound. The efficacy of generated antibodies was evaluated against different PA strains through several in vitro, ex vivo and in vivo experiments. The results showed that the anti-PAO1-IgY effectively reduced the motility, biofilm formation and cell internalization ability, and enhanced the opsonophagocytic killing of PA strains through the formation of immobilized bacteria and induction of increased cell surface hydrophobicity. Furthermore, immunotherapy with anti-PAO1-IgY completely protected mice against all PA strains in both acute pneumonia and burn wound murine models. It was found to reduce the bacterial loads in infected burned mice through interfering with virulence factors that play vital roles in the early stages of PA infection, such as colonization and cell internalization. The immunotherapy with anti-PAO1-IgYs could be instrumental in developing effective therapies aimed at reducing the morbidity and mortality associated with PA infections.
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Affiliation(s)
- Tooba Sadat Ahmadi
- Department of Biology, Faculty of Basic Sciences, Shahed University, Tehran-Qom Express Way, Tehran, 3319118651, Iran
| | - Bahador Behrouz
- Department of Biology, Faculty of Basic Sciences, Shahed University, Tehran-Qom Express Way, Tehran, 3319118651, Iran
| | - Seyed Latif Mousavi Gargari
- Department of Biology, Faculty of Basic Sciences, Shahed University, Tehran-Qom Express Way, Tehran, 3319118651, Iran.
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Radzikowska-Büchner E, Łopuszyńska I, Flieger W, Tobiasz M, Maciejewski R, Flieger J. An Overview of Recent Developments in the Management of Burn Injuries. Int J Mol Sci 2023; 24:16357. [PMID: 38003548 PMCID: PMC10671630 DOI: 10.3390/ijms242216357] [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: 09/25/2023] [Revised: 11/09/2023] [Accepted: 11/13/2023] [Indexed: 11/26/2023] Open
Abstract
According to the World Health Organization (WHO), around 11 million people suffer from burns every year, and 180,000 die from them. A burn is a condition in which heat, chemical substances, an electrical current or other factors cause tissue damage. Burns mainly affect the skin, but can also affect deeper tissues such as bones or muscles. When burned, the skin loses its main functions, such as protection from the external environment, pathogens, evaporation and heat loss. Depending on the stage of the burn, the patient's condition and the cause of the burn, we need to choose the most appropriate treatment. Personalization and multidisciplinary collaboration are key to the successful management of burn patients. In this comprehensive review, we have collected and discussed the available treatment options, focusing on recent advances in topical treatments, wound cleansing, dressings, skin grafting, nutrition, pain and scar tissue management.
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Affiliation(s)
- Elżbieta Radzikowska-Büchner
- Department of Plastic, Reconstructive and Maxillary Surgery, National Medical Institute of the Ministry of the Interior and Administration, Wołoska 137 Street, 02-507 Warszawa, Poland;
| | - Inga Łopuszyńska
- Department of Plastic, Reconstructive and Maxillary Surgery, National Medical Institute of the Ministry of the Interior and Administration, Wołoska 137 Street, 02-507 Warszawa, Poland;
| | - Wojciech Flieger
- Department of Human Anatomy, Medical University of Lublin, Jaczewskiego 4 Street, 20-090 Lublin, Poland;
| | - Michał Tobiasz
- Department of Plastic Surgery, Reconstructive Surgery and Burn Treatment, Medical University of Lublin, Krasnystawska 52 Street, 21-010 Łęczna, Poland;
| | - Ryszard Maciejewski
- Faculty of Medicine, University of Warsaw, Żwirki i Wigury 101 Street, 02-089 Warszawa, Poland;
| | - Jolanta Flieger
- Department of Analytical Chemistry, Medical University of Lublin, Chodźki 4A Street, 20-093 Lublin, Poland
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Greenhalgh DG, Hill DM, Burmeister DM, Gus EI, Cleland H, Padiglione A, Holden D, Huss F, Chew MS, Kubasiak JC, Burrell A, Manzanares W, Gómez MC, Yoshimura Y, Sjöberg F, Xie WG, Egipto P, Lavrentieva A, Jain A, Miranda-Altamirano A, Raby E, Aramendi I, Sen S, Chung KK, Alvarez RJQ, Han C, Matsushima A, Elmasry M, Liu Y, Donoso CS, Bolgiani A, Johnson LS, Vana LPM, de Romero RVD, Allorto N, Abesamis G, Luna VN, Gragnani A, González CB, Basilico H, Wood F, Jeng J, Li A, Singer M, Luo G, Palmieri T, Kahn S, Joe V, Cartotto R. Surviving Sepsis After Burn Campaign. Burns 2023; 49:1487-1524. [PMID: 37839919 DOI: 10.1016/j.burns.2023.05.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Accepted: 05/02/2023] [Indexed: 10/17/2023]
Abstract
INTRODUCTION The Surviving Sepsis Campaign was developed to improve outcomes for all patients with sepsis. Despite sepsis being the primary cause of death after thermal injury, burns have always been excluded from the Surviving Sepsis efforts. To improve sepsis outcomes in burn patients, an international group of burn experts developed the Surviving Sepsis After Burn Campaign (SSABC) as a testable guideline to improve burn sepsis outcomes. METHODS The International Society for Burn Injuries (ISBI) reached out to regional or national burn organizations to recommend members to participate in the program. Two members of the ISBI developed specific "patient/population, intervention, comparison and outcome" (PICO) questions that paralleled the 2021 Surviving Sepsis Campaign [1]. SSABC participants were asked to search the current literature and rate its quality for each topic. At the Congress of the ISBI, in Guadalajara, Mexico, August 28, 2022, a majority of the participants met to create "statements" based on the literature. The "summary statements" were then sent to all members for comment with the hope of developing an 80% consensus. After four reviews, a consensus statement for each topic was created or "no consensus" was reported. RESULTS The committee developed sixty statements within fourteen topics that provide guidance for the early treatment of sepsis in burn patients. These statements should be used to improve the care of sepsis in burn patients. The statements should not be considered as "static" comments but should rather be used as guidelines for future testing of the best treatments for sepsis in burn patients. They should be updated on a regular basis. CONCLUSION Members of the burn community from the around the world have developed the Surviving Sepsis After Burn Campaign guidelines with the goal of improving the outcome of sepsis in burn patients.
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Affiliation(s)
- David G Greenhalgh
- Department of Burns, Shriners Children's Northern California and Department of Surgery, University of California, Davis, Sacramento, CA, USA.
| | - David M Hill
- Department of Clinical Pharmacy & Translational Scre have been several studies that have evaluatedience, College of Pharmacy, University of Tennessee, Health Science Center; Memphis, TN, USA
| | - David M Burmeister
- Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
| | - Eduardo I Gus
- Division of Plastic & Reconstructive Surgery, The Hospital for Sick Children; Department of Surgery, University of Toronto, Toronto, Canada
| | - Heather Cleland
- Department of Surgery, Monash University and Alfred Hospital, Melbourne, Australia
| | - Alex Padiglione
- Department of Surgery, Monash University and Alfred Hospital, Melbourne, Australia
| | - Dane Holden
- Department of Surgery, Monash University and Alfred Hospital, Melbourne, Australia
| | - Fredrik Huss
- Department of Surgical Sciences, Plastic Surgery, Uppsala University/Burn Center, Department of Plastic and Maxillofacial Surgery, Uppsala University Hospital, Uppsala, Sweden
| | - Michelle S Chew
- Department of Anaesthesia and Intensive Care, Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - John C Kubasiak
- Department of Surgery, Loyola University Medical Center, Maywood, IL, USA
| | - Aidan Burrell
- Department of Epidemiology and Preventative Medicine, Monash University and Alfred Hospital, Intensive Care Research Center (ANZIC-RC), Melbourne, Australia
| | - William Manzanares
- Department of Critical Care Medicine, Universidad de la República (UdelaR), Montevideo, Uruguay
| | - María Chacón Gómez
- Division of Intensive Care and Critical Medicine, Centro Nacional de Investigacion y Atencion de Quemados (CENIAQ), National Rehabilitation Institute, LGII, Mexico
| | - Yuya Yoshimura
- Department of Emergency and Critical Care Medicine, Hachinohe City Hospital, Hachinohe, Japan
| | - Folke Sjöberg
- Department of Anaesthesia and Intensive Care, Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Wei-Guo Xie
- Institute of Burns, Tongren Hospital of Wuhan University (Wuhan Third Hospital), Wuhan, China
| | - Paula Egipto
- Centro Hospitalar e Universitário São João - Burn Unit, Porto, Portugal
| | | | | | | | - Ed Raby
- Infectious Diseases Department, Fiona Stanley Hospital, Murdoch, Western Australia, Australia
| | | | - Soman Sen
- Department of Burns, Shriners Children's Northern California and Department of Surgery, University of California, Davis, Sacramento, CA, USA
| | - Kevin K Chung
- Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
| | | | - Chunmao Han
- Department of Burn and Wound Repair, Second Affiliated Hospital, Zhejiang University College of Medicine, Hangzhou, China
| | - Asako Matsushima
- Department of Emergency and Critical Care, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Moustafa Elmasry
- Department of Hand, Plastic Surgery and Burns, Linköping University, Linköping, Sweden
| | - Yan Liu
- Department of Burn, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Carlos Segovia Donoso
- Intensive Care Unit for Major Burns, Mutual Security Clinical Hospital, Santiago, Chile
| | - Alberto Bolgiani
- Department of Surgery, Deutsches Hospital, Buenos Aires, Argentina
| | - Laura S Johnson
- Department of Surgery, Emory University School of Medicine and Grady Health System, Georgia
| | - Luiz Philipe Molina Vana
- Disciplina de Cirurgia Plastica da Escola Paulista de Medicina da Universidade Federal de Sao Paulo, Sao Paulo, Brazil
| | | | - Nikki Allorto
- Grey's Hospital Pietermaritzburg Metropolitan Burn Service, University of KwaZulu Natal, Pietermaritzburg, South Africa
| | - Gerald Abesamis
- Alfredo T. Ramirez Burn Center, Division of Burns, Department of Surgery, University of Philippines Manila - Philippine General Hospital, Manila, Philippines
| | - Virginia Nuñez Luna
- Unidad Michou y Mau Xochimilco for Burnt Children, Secretaria Salud Ciudad de México, Mexico
| | - Alfredo Gragnani
- Disciplina de Cirurgia Plastica da Escola Paulista de Medicina da Universidade Federal de Sao Paulo, Sao Paulo, Brazil
| | - Carolina Bonilla González
- Department of Pediatrics and Intensive Care, Pediatric Burn Unit, Clinical Studies and Clinical Epidemiology Division, Fundación Santa Fe de Bogotá, Bogotá, Colombia
| | - Hugo Basilico
- Intensive Care Area - Burn Unit - Pediatric Hospital "Prof. Dr. Juan P. Garrahan", Buenos Aires, Argentina
| | - Fiona Wood
- Department of Surgery, Fiona Stanley Hospital, Murdoch, Western Australia, Australia
| | - James Jeng
- Department of Surgery, University of California, Irvine, CA, USA
| | - Andrew Li
- Department of Surgery, Monash University and Alfred Hospital, Melbourne, Australia
| | - Mervyn Singer
- Department of Intensive Care Medicine, University College London, London, United Kingdom
| | - Gaoxing Luo
- Institute of Burn Research, Southwest Hospital, Army (Third Military) Medical University, Chongqing, China
| | - Tina Palmieri
- Department of Burns, Shriners Children's Northern California and Department of Surgery, University of California, Davis, Sacramento, CA, USA
| | - Steven Kahn
- The South Carolina Burn Center, Department of Surgery, Medical University of South Carolina, Charleston, SC, USA
| | - Victor Joe
- Department of Surgery, University of California, Irvine, CA, USA
| | - Robert Cartotto
- Department of Surgery, Sunnybrook Medical Center, Toronto, Ontario, Canada
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Evani SJ, Chen P, Karna SR, D'Arpa P, Leung KP. Cerium Nitrate Stiffens In Vitro Skin Models and Reduces Pseudomonas aeruginosa Pathogenicity and Penetration Through Skin Models. Adv Wound Care (New Rochelle) 2023; 12:546-559. [PMID: 36394961 PMCID: PMC10387153 DOI: 10.1089/wound.2022.0026] [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: 03/14/2022] [Accepted: 11/12/2022] [Indexed: 11/18/2022] Open
Abstract
Objective: Cerium nitrate (CeN) plus silver sulfadiazine (SSD) cream has been used for 40-plus years to manage burns. CeN produces a hardened eschar believed to resist bacterial colonization/infection. To evaluate this potential mechanism, we treated in vitro skin models or Pseudomonas aeruginosa with CeN and measured mechanical properties of the models and bacterial virulence, respectively. Approach: We treated three-dimensional-collagen matrix and ex-vivo-burned porcine skin with CeN and evaluated stiffness and P. aeruginosa penetration. In addition, we treated P. aeruginosa with CeN and evaluated the bacteria's motility, skin model penetration, susceptibility to be phagocytized by the human monocytic cell line THP-1, and ability to stimulate this cell line to produce cytokines. Results: CeN treatment of skin models stiffened them and made them resistant to P. aeruginosa penetration. Inversely, CeN treatment of P. aeruginosa reduced their motility, penetration through skin models (ex-vivo-burned porcine skin), and ability to stimulate cytokine production (tumor necrosis factor-α [TNF-α] and interleukin 8 [IL-8]) by THP-1 cells. In addition, CeN-treated Pseudomonas was more readily phagocytized by THP-1 cells. Finally, P. aeruginosa inoculated on CeN-treated ex-vivo-burned porcine skin was more susceptible to killing by a silver dressing. Innovation: In vitro skin models offer a platform for screening drugs that interfere with bacterial penetration into wounded tissue. Conclusion: CeN treatment reduced P. aeruginosa virulence, altered the mechanical properties of ex-vivo-burned porcine skin and collagen matrix, retarded penetration of P. aeruginosa through the skin models, and resulted in increased vulnerability of P. aeruginosa to killing by antimicrobial wound dressings. These data support the use of CeN in burn management.
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Affiliation(s)
- Shankar J. Evani
- Combat Wound Care Group, United States Army Institute of Surgical Research, Fort Sam Houston, Texas, USA
| | - Ping Chen
- Combat Wound Care Group, United States Army Institute of Surgical Research, Fort Sam Houston, Texas, USA
| | - S.L. Rajasekhar Karna
- Combat Wound Care Group, United States Army Institute of Surgical Research, Fort Sam Houston, Texas, USA
| | - Peter D'Arpa
- Combat Wound Care Group, United States Army Institute of Surgical Research, Fort Sam Houston, Texas, USA
| | - Kai P. Leung
- Combat Wound Care Group, United States Army Institute of Surgical Research, Fort Sam Houston, Texas, USA
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Nazeih SI, Ali MAM, Halim ASA, Al-Lawati H, Abbas HA, Al-Zharani M, Boufahja F, Alghamdi MA, Hegazy WAH, Seleem NM. Relocating Glyceryl Trinitrate as an Anti-Virulence Agent against Pseudomonas aeruginosa and Serratia marcescens: Insights from Molecular and In Vivo Investigations. Microorganisms 2023; 11:2420. [PMID: 37894078 PMCID: PMC10609227 DOI: 10.3390/microorganisms11102420] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 09/23/2023] [Accepted: 09/24/2023] [Indexed: 10/29/2023] Open
Abstract
The problem of antibiotic resistance is a global critical public health concern. In light of the threat of returning to the pre-antibiotic era, new alternative approaches are required such as quorum-sensing (QS) disruption and virulence inhibition, both of which apply no discernible selective pressure on bacteria, therefore mitigating the potential for the development of resistant strains. Bearing in mind the significant role of QS in orchestrating bacterial virulence, disrupting QS becomes essential for effectively diminishing bacterial virulence. This study aimed to assess the potential use of sub-inhibitory concentration (0.25 mg/mL) of glyceryl trinitrate (GTN) to inhibit virulence in Serratia marcescens and Pseudomonas aeruginosa. GTN could decrease the expression of virulence genes in both tested bacteria in a significant manner. Histopathological study revealed the ability of GTN to alleviate the congestion in hepatic and renal tissues of infected mice and to reduce bacterial and leukocyte infiltration. This study recommends the use of topical GTN to treat topical infection caused by P. aeruginosa and S. marcescens in combination with antibiotics.
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Affiliation(s)
- Shaimaa I. Nazeih
- Department of Microbiology and Immunology, Faculty of Pharmacy, Zagazig University, Zagazig 44519, Egypt; (S.I.N.); (H.A.A.); (N.M.S.)
| | - Mohamed A. M. Ali
- Department of Biology, College of Science, Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh 11623, Saudi Arabia; (M.A.M.A.); (F.B.)
- Department of Biochemistry, Faculty of Science, Ain Shams University, Abbassia, Cairo 11566, Egypt;
| | - Alyaa S. Abdel Halim
- Department of Biochemistry, Faculty of Science, Ain Shams University, Abbassia, Cairo 11566, Egypt;
| | - Hanan Al-Lawati
- Pharmacy Program, Department of Pharmaceutics, Oman College of Health Sciences, Muscat 113, Oman;
| | - Hisham A. Abbas
- Department of Microbiology and Immunology, Faculty of Pharmacy, Zagazig University, Zagazig 44519, Egypt; (S.I.N.); (H.A.A.); (N.M.S.)
| | - Mohammed Al-Zharani
- Department of Biology, College of Science, Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh 11623, Saudi Arabia; (M.A.M.A.); (F.B.)
| | - Fehmi Boufahja
- Department of Biology, College of Science, Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh 11623, Saudi Arabia; (M.A.M.A.); (F.B.)
| | - Mashael A. Alghamdi
- Department of Chemistry, Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh 11623, Saudi Arabia;
| | - Wael A. H. Hegazy
- Department of Microbiology and Immunology, Faculty of Pharmacy, Zagazig University, Zagazig 44519, Egypt; (S.I.N.); (H.A.A.); (N.M.S.)
- Pharmacy Program, Department of Pharmaceutical Sciences, Oman College of Health Sciences, Muscat 113, Oman
| | - Noura M. Seleem
- Department of Microbiology and Immunology, Faculty of Pharmacy, Zagazig University, Zagazig 44519, Egypt; (S.I.N.); (H.A.A.); (N.M.S.)
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8
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Das T, Das B, Young BC, Aldilla V, Sabir S, Almohaywi B, Willcox M, Manefield M, Kumar N. Ascorbic acid modulates the structure of the Pseudomonas aeruginosa virulence factor pyocyanin and ascorbic acid-furanone-30 combination facilitate biofilm disruption. Front Microbiol 2023; 14:1166607. [PMID: 37520362 PMCID: PMC10381918 DOI: 10.3389/fmicb.2023.1166607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Accepted: 06/26/2023] [Indexed: 08/01/2023] Open
Abstract
The production of pyocyanin by Pseudomonas aeruginosa increases its virulence, fitness and biofilm formation. Pyocyanin is also a redox molecule and we hypothesize that ascorbic acid being an antioxidant will interact with pyocyanin. The main objective of this study was to investigate the potential interaction of ascorbic acid with pyocyanin, and also to investigate the impact of ascorbic acid in combination with Furanone-30 on quorum sensing and biofilm formation of P. aeruginosa. When incubated with ascorbic acid, hyperchromic and hypsochromic shifts in pyocyanin absorbance peaks at 385 nm and 695 nm were observed. In the presence of dehydroascorbic acid and citric acid, these shifts were absent, indicating that the intrinsic antioxidant property of ascorbic acid was probably essential in binding to pyocyanin. NMR spectroscopy showed shifts in 1H NMR pyocyanin peaks between 8.2 to 5.8 ppm when incubated in the presence of ascorbic acid. Density Functional Theory (DFT) supported potential interactions between the -CH2OH or -OH moieties of ascorbic acid with the -C=O moiety of pyocyanin. The pyocyanin-ascorbic acid complex impaired pyocyanin binding to DNA. Ascorbic acid combined with furanone-30 elevated quorum-sensing inhibition in P. aeruginosa, which was directly associated with significantly reduced P. aeruginosa virulence, adhesion, aggregation and biofilm formation and enhanced antibiotic-mediated bacterial killing. This study demonstrated that the antioxidant ascorbic acid directly binds to pyocyanin, modulates its structure and results in disruption of biofilm formation and associated tolerance to antibiotics.
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Affiliation(s)
- Theerthankar Das
- Infection Immunity and Inflammation, Charles Perkins Centre, School of Medical Science, The University of Sydney, Sydney, NSW, Australia
- Sydney Institute for Infectious Diseases, School of Medical Science, The University of Sydney, Sydney, NSW, Australia
| | - Biswanath Das
- Department of Organic Chemistry, Arrhenius Laboratory Stockholm University, Stockholm, Sweden
- School of Chemistry, University of New South Wales (UNSW), Sydney, NSW, Australia
| | - Brandon Clark Young
- Infection Immunity and Inflammation, Charles Perkins Centre, School of Medical Science, The University of Sydney, Sydney, NSW, Australia
| | - Vina Aldilla
- School of Chemistry, University of New South Wales (UNSW), Sydney, NSW, Australia
| | - Shekh Sabir
- School of Chemistry, University of New South Wales (UNSW), Sydney, NSW, Australia
| | - Basmah Almohaywi
- College of Pharmacy, King Khalid University (KKU), Abha, Saudi Arabia
| | - Mark Willcox
- School of Optometry and Vision Science, The University of New South Wales, Sydney, NSW, Australia
| | - Mike Manefield
- School of Chemical Engineering, University of New South Wales (UNSW), Sydney, NSW, Australia
| | - Naresh Kumar
- School of Chemistry, University of New South Wales (UNSW), Sydney, NSW, Australia
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9
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Buriro F, Ishaque S, Saeed A, Qamar MA, Batool A. Prevalence of Multidrug-Resistant Organism in ICU Burns Patients at Tertiary Care Hospital. J Burn Care Res 2023; 44:949-954. [PMID: 36305838 DOI: 10.1093/jbcr/irac160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/20/2023]
Abstract
Burns carries a high-risk of mortality and morbidity. This with increased chances of drug-resistant infections makes the management complicated. Hence this study was conducted to find out the prevalence of multidrug-resistant organisms (MDRO) in burns patients admitted to the intensive care unit at a tertiary care hospital. A 2-year retrospective study was conducted where burn patients reporting MDRO were included. Statistical analysis was performed using SPSS version 26 where a P-value < .05 was considered statistically significant. Out of 97 patients, tissue cultures of 65 patients revealed the presence of MDRO in 27 (27.8%) patients. A male predominance (17, 63.0%) was noted with a mean age of 29.0-year-old. Fire burn (15, 55.6%) was reported to be the most common cause of burn with an average of 29.9% of Total Body Surface Area (TBSA) involved. MDR Pseudomonas aeruginosa was the commonest organism reported in 12 (44%) patients. The average length of stay (LOS) was noted to be 11.3 days with a mortality rate of 48.1% (overall, in all MDRO'S infections). Patients who reported MDRO showed a tendency for longer hospitalization with a higher risk of mortality as the TBSA increased. However, in presence of other factors in burns like higher TBSA, inhalation injury and lack of advanced skin substitute these mortality figures, and their association can be debated. Lastly, the implementation of control measures, as basic as hand hygiene, should be partaken to reduce the burden of MDR infections.
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Affiliation(s)
- Fahmina Buriro
- Department of Plastic Surgery, Patel Hospital, Karachi, Pakistan
| | - Sadia Ishaque
- Consultant Infectious Diseases, Shaheed Mohtarma, Benazir Bhutto Institute of Trauma Karachi, Pakistan
| | - Aniqa Saeed
- Department of Surgery, Aga Khan University Hospital, Karachi, Pakistan
| | | | - Amna Batool
- Department of Plastic Surgery, Patel Hospital, Karachi, Pakistan
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10
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Bagheri M, von Kohout M, Zoric A, Fuchs PC, Schiefer JL, Opländer C. Can Cold Atmospheric Plasma Be Used for Infection Control in Burns? A Preclinical Evaluation. Biomedicines 2023; 11:biomedicines11051239. [PMID: 37238910 DOI: 10.3390/biomedicines11051239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 04/16/2023] [Accepted: 04/19/2023] [Indexed: 05/28/2023] Open
Abstract
Wound infection with Pseudomonas aeruginosa (PA) is a serious complication and is responsible for higher rates of mortality in burn patients. Because of the resistance of PA to many antibiotics and antiseptics, an effective treatment is difficult. As a possible alternative, cold atmospheric plasma (CAP) can be considered for treatment, as antibacterial effects are known from some types of CAP. Hence, we preclinically tested the CAP device PlasmaOne and found that CAP was effective against PA in various test systems. CAP induced an accumulation of nitrite, nitrate, and hydrogen peroxide, combined with a decrease in pH in agar and solutions, which could be responsible for the antibacterial effects. In an ex vivo contamination wound model using human skin, a reduction in microbial load of about 1 log10 level was observed after 5 min of CAP treatment as well as an inhibition of biofilm formation. However, the efficacy of CAP was significantly lower when compared with commonly used antibacterial wound irrigation solutions. Nevertheless, a clinical use of CAP in the treatment of burn wounds is conceivable on account of the potential resistance of PA to common wound irrigation solutions and the possible wound healing-promoting effects of CAP.
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Affiliation(s)
- Mahsa Bagheri
- Plastic Surgery, Hand Surgery, Burn Center, Cologne-Merheim Hospital, Witten/Herdecke University, Ostmerheimer Str. 200, 51109 Cologne, Germany
- Institute for Research in Operative Medicine (IFOM), Cologne-Merheim Hospital, Witten/Herdecke University, Ostmerheimer Str. 200, 51109 Cologne, Germany
| | - Maria von Kohout
- Plastic Surgery, Hand Surgery, Burn Center, Cologne-Merheim Hospital, Witten/Herdecke University, Ostmerheimer Str. 200, 51109 Cologne, Germany
- Institute for Research in Operative Medicine (IFOM), Cologne-Merheim Hospital, Witten/Herdecke University, Ostmerheimer Str. 200, 51109 Cologne, Germany
| | - Andreas Zoric
- Institute for Research in Operative Medicine (IFOM), Cologne-Merheim Hospital, Witten/Herdecke University, Ostmerheimer Str. 200, 51109 Cologne, Germany
| | - Paul C Fuchs
- Plastic Surgery, Hand Surgery, Burn Center, Cologne-Merheim Hospital, Witten/Herdecke University, Ostmerheimer Str. 200, 51109 Cologne, Germany
| | - Jennifer L Schiefer
- Plastic Surgery, Hand Surgery, Burn Center, Cologne-Merheim Hospital, Witten/Herdecke University, Ostmerheimer Str. 200, 51109 Cologne, Germany
| | - Christian Opländer
- Institute for Research in Operative Medicine (IFOM), Cologne-Merheim Hospital, Witten/Herdecke University, Ostmerheimer Str. 200, 51109 Cologne, Germany
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11
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Leder MCD, Bagheri M, Plattfaut I, Fuchs PC, Brüning AKE, Schiefer JL, Opländer C. Phototherapy of Pseudomonas aeruginosa-Infected Wounds: Preclinical Evaluation of Antimicrobial Blue Light (450-460 nm) Using In Vitro Assays and a Human Wound Skin Model. Photobiomodul Photomed Laser Surg 2022; 40:800-809. [PMID: 36306523 DOI: 10.1089/photob.2022.0005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Objective: To determine effective treatment strategies against bacterial infections of burn wounds with Pseudomonas aeruginosa, we tested different treatment regimens with antibacterial blue light (BL). Background: Infections of burn wounds are serious complications and require effective and pathogen-specific therapy. Hereby, infections caused by P. aeruginosa pose a particular challenge in clinical practice due to its resistance to many antibiotics and topical antiseptics. Methods: LED-based light sources (450-460 nm) with different intensities and treatment times were used. Antibacterial effects against P. aeruginosa were determined by colony-forming unit (CFU) assays, human skin wound models, and fluorescence imaging. Results: In suspension assays, BL (2 h, 40 mW/cm2, 288 J/cm2) reduced bacterial number (>5 log10 CFU/mL). Applying 144 J/cm2, using 40 mW/cm2 for 1 h was more effective (>4 log10 CFU) than using 20 mW/cm2 for 2 h (>1.5 log10 CFU). BL with low irradiance (24 h, 3.5 mW/cm2, 300 J/cm2) only revealed bacterial reduction in thin bacteria-containing medium layers. In infected in vitro skin wounds only BL irradiation (2 h, 40 mW/cm2, 288 J/cm2) exerted a significant antimicrobial efficacy (2.94 log10 CFU/mL). Conclusions: BL treatment may be an effective therapy for P. aeruginosa-infected wounds to avoid radical surgical debridement. However, a significant antibacterial efficacy can only be achieved with higher irradiances and longer treatment times (min. 40 mW/cm2; >1 h), which cannot be easily integrated into regular clinical treatment protocols, for example, during a dressing change. Further studies are necessary to establish BL therapy for infected burns among tissue compatibility and interactions with previous therapeutic agents.
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Affiliation(s)
- Marie-Charlotte D Leder
- Centre for Biomedical Education and Research (ZBAF), Witten/Herdecke University, Witten, Germany
| | - Mahsa Bagheri
- Plastic Surgery, Hand Surgery, Burn Center, Cologne-Merheim Hospital, Witten/Herdecke University, Cologne, Germany
| | - Isabell Plattfaut
- Centre for Biomedical Education and Research (ZBAF), Witten/Herdecke University, Witten, Germany
| | - Paul C Fuchs
- Plastic Surgery, Hand Surgery, Burn Center, Cologne-Merheim Hospital, Witten/Herdecke University, Cologne, Germany
| | - Anne K E Brüning
- Clinic for Thoracic and Cardiovascular Surgery, Heart and Diabetes Center North Rhine Westphalia, Bad Oeynhausen, Germany
| | - Jennifer L Schiefer
- Plastic Surgery, Hand Surgery, Burn Center, Cologne-Merheim Hospital, Witten/Herdecke University, Cologne, Germany
| | - Christian Opländer
- Institute for Research in Operative Medicine (IFOM), Cologne-Merheim Medical Center, Witten/Herdecke University, Cologne, Germany
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12
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Effect of samarium oxide nanoparticles on virulence factors and motility of multi-drug resistant Pseudomonas aeruginosa. World J Microbiol Biotechnol 2022; 38:209. [PMID: 36040540 DOI: 10.1007/s11274-022-03384-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2022] [Accepted: 08/09/2022] [Indexed: 10/14/2022]
Abstract
Biofilm formation and quorum sensing (QS) dependent virulence factors are considered the major causes of the emergence of drug resistance, therapeutic failure and development of Pseudomonas aeruginosa infections. This study aimed to investigate the effects of samarium oxide nanoparticles (Sm2O3NPs) on biofilm, virulence factors, and motility of multidrug-resistant P. aeruginosa. Sm2O3NPs were synthesized using curcumin and characterized by Transmission Electron Microscopy, X-ray diffractometer, Field Emission Scanning Electron Microscopy, and Energy-dispersive X-ray spectroscopy. Minimum inhibitory concentration (MIC) was determined using broth microdilution method. The antibiofilm potential of Sm2O3NPs was also evaluated by crystal violet staining and light microscopy examination. Then, the effect of sub-MICs concentrations of Sm2O3NPs on the proteolytic and hemolytic activities of P. aeruginosa was investigated. Finally, the effect of Sm2O3NPs on various types of motility including swarming, swimming, and twitching was studied. Our results showed that Sm2O3NPs significantly inhibited biofilm formation of P. aeruginosa by 49-61%. Additionally, sub-MICs concentrations of Sm2O3NPs effectively decreased virulence factors including pyocyanin (33-55%), protease (24-45%), and hemolytic activity (22-41%). Moreover, swarming, swimming, and twitching motility remarkably was reduced after exposure to the NPs. The findings of this work showed that Sm2O3NPs have a high potential in inhibiting QS-dependent virulence of P. aeruginosa, which could be considered for antibacterial chemotherapy after further characterization.
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13
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Calum H, Trøstrup H, Laulund AS, Thomsen K, Christophersen L, Høiby N, Moser C. Murine burn lesion model for studying acute and chronic wound infections. APMIS 2022; 130:477-490. [PMID: 35441434 DOI: 10.1111/apm.13228] [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: 03/05/2021] [Accepted: 04/13/2022] [Indexed: 02/05/2023]
Abstract
Acute wounds, such as thermal injury, and chronic wounds are challenging for patients and the healthcare system around the world. Thermal injury of considerable size induces immunosuppression, which renders the patient susceptible to wound infections, but also in other foci like the airways and urinary tract. Infected thermal lesions can progress to chronic wounds with biofilm making them more difficult to treat. While animal models have their limitations, murine wound models are still the best tool at the moment to identify strategies to overcome these challenges. Here, we present a murine burn model, which has been developed to study biofilm formation, the significance of wound healing, and for identifying novel treatment candidates. Investigating the effect of a thermal injury in mice, we observed that 48 h after introduction of the injury, the mice showed a reduction in polymorphonuclear neutrophil granulocytes (PMNs) and a reduced capacity for phagocytosis and oxidative burst. Regarding the chronic wound, Pseudomonas aeruginosa biofilm arrested wound healing and kept the wound in an inflammatory state, but suppressing PMN function by means of the PMN factor S100A8/A9, corresponding to observations in human venous leg ulcers. Monotherapy and dual treatment with S100A8/A9 and ciprofloxacin on P. aeruginosa biofilm-infected murine wounds have been investigated. In combination, S100A8/A9 and ciprofloxacin reduced the bacterial quantity, lowered the proinflammatory response, and increased anti-inflammatory cytokines after 4 days of treatment. When the treatment was prolonged, an additional prevention of resistance development was detected in all the dual-treated mice. In the present review, we provide data on using the murine model for research with the aim of better understanding pathophysiology of wounds and for identifying novel treatments for humans suffering from these lesions.
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Affiliation(s)
- Henrik Calum
- Department of Clinical Microbiology, Hvidovre Hospital, Copenhagen University Hospital, Copenhagen, Denmark
| | - Hannah Trøstrup
- Department of Plastic Surgery and Burns Treatment, Copenhagen University Hospital, Copenhagen, Denmark
| | - Anne Sofie Laulund
- Department of Clinical Microbiology, Copenhagen University Hospital, Copenhagen, Denmark
| | - Kim Thomsen
- Department of Clinical Microbiology, Copenhagen University Hospital, Copenhagen, Denmark
| | - Lars Christophersen
- Department of Clinical Microbiology, Copenhagen University Hospital, Copenhagen, Denmark
| | - Niels Høiby
- Department of Clinical Microbiology, Copenhagen University Hospital, Copenhagen, Denmark
- Department of Immunology and Microbiology (ISIM), University of Copenhagen, Copenhagen, Denmark
| | - Claus Moser
- Department of Clinical Microbiology, Copenhagen University Hospital, Copenhagen, Denmark
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14
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Bach MS, de Vries CR, Khosravi A, Sweere JM, Popescu MC, Chen Q, Demirdjian S, Hargil A, Van Belleghem JD, Kaber G, Hajfathalian M, Burgener EB, Liu D, Tran QL, Dharmaraj T, Birukova M, Sunkari V, Balaji S, Ghosh N, Mathew-Steiner SS, El Masry MS, Keswani SG, Banaei N, Nedelec L, Sen CK, Chandra V, Secor PR, Suh GA, Bollyky PL. Filamentous bacteriophage delays healing of Pseudomonas-infected wounds. Cell Rep Med 2022; 3:100656. [PMID: 35732145 PMCID: PMC9244996 DOI: 10.1016/j.xcrm.2022.100656] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 03/29/2022] [Accepted: 05/17/2022] [Indexed: 01/09/2023]
Abstract
Chronic wounds infected by Pseudomonas aeruginosa (Pa) are characterized by disease progression and increased mortality. We reveal Pf, a bacteriophage produced by Pa that delays healing of chronically infected wounds in human subjects and animal models of disease. Interestingly, impairment of wound closure by Pf is independent of its effects on Pa pathogenesis. Rather, Pf impedes keratinocyte migration, which is essential for wound healing, through direct inhibition of CXCL1 signaling. In support of these findings, a prospective cohort study of 36 human patients with chronic Pa wound infections reveals that wounds infected with Pf-positive strains of Pa are more likely to progress in size compared with wounds infected with Pf-negative strains. Together, these data implicate Pf phage in the delayed wound healing associated with Pa infection through direct manipulation of mammalian cells. These findings suggest Pf may have potential as a biomarker and therapeutic target in chronic wounds.
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Affiliation(s)
- Michelle S Bach
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA 94305, USA; Stanford Immunology, Stanford University, Stanford, CA 94305, USA
| | - Christiaan R de Vries
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA 94305, USA
| | - Arya Khosravi
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA 94305, USA
| | - Johanna M Sweere
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA 94305, USA; Stanford Immunology, Stanford University, Stanford, CA 94305, USA
| | - Medeea C Popescu
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA 94305, USA; Stanford Immunology, Stanford University, Stanford, CA 94305, USA
| | - Qingquan Chen
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA 94305, USA
| | - Sally Demirdjian
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA 94305, USA
| | - Aviv Hargil
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA 94305, USA
| | - Jonas D Van Belleghem
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA 94305, USA
| | - Gernot Kaber
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA 94305, USA
| | - Maryam Hajfathalian
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA 94305, USA; Department of Radiology, University of Pennsylvania, Philadelphia, PA, USA
| | - Elizabeth B Burgener
- Center for Excellence in Pulmonary Biology, Department of Pediatrics, Stanford University, Stanford, CA 94305, USA
| | - Dan Liu
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA 94305, USA
| | - Quynh-Lam Tran
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA 94305, USA
| | - Tejas Dharmaraj
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA 94305, USA; Stanford Immunology, Stanford University, Stanford, CA 94305, USA
| | - Maria Birukova
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA 94305, USA; Stanford Immunology, Stanford University, Stanford, CA 94305, USA
| | - Vivekananda Sunkari
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA 94305, USA; Stanford Immunology, Stanford University, Stanford, CA 94305, USA
| | - Swathi Balaji
- Division of Pediatric Surgery, Department of Surgery, Baylor College of Medicine, Houston, TX 77030, USA
| | - Nandini Ghosh
- Department of Surgery, Indiana University, Indianapolis, IN 46202, USA
| | | | | | - Sundeep G Keswani
- Division of Pediatric Surgery, Department of Surgery, Baylor College of Medicine, Houston, TX 77030, USA
| | - Niaz Banaei
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA 94305, USA; Division of Pathology, Department of Medicine, Stanford University, Stanford, CA 94305, USA
| | - Laurence Nedelec
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA 94305, USA
| | - Chandan K Sen
- Department of Surgery, Indiana University, Indianapolis, IN 46202, USA
| | - Venita Chandra
- Department of Surgery, Division of Vascular Surgery, Stanford University, Stanford, CA 94305, USA
| | - Patrick R Secor
- Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA
| | - Gina A Suh
- Division of Infectious Diseases, Mayo Clinic, Rochester, MN 55902, USA
| | - Paul L Bollyky
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA 94305, USA.
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15
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Resistance Is Not Futile: The Role of Quorum Sensing Plasticity in Pseudomonas aeruginosa Infections and Its Link to Intrinsic Mechanisms of Antibiotic Resistance. Microorganisms 2022; 10:microorganisms10061247. [PMID: 35744765 PMCID: PMC9228389 DOI: 10.3390/microorganisms10061247] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Revised: 06/06/2022] [Accepted: 06/09/2022] [Indexed: 01/01/2023] Open
Abstract
Bacteria use a cell-cell communication process called quorum sensing (QS) to orchestrate collective behaviors. QS relies on the group-wide detection of extracellular signal molecules called autoinducers (AI). Quorum sensing is required for virulence and biofilm formation in the human pathogen Pseudomonas aeruginosa. In P. aeruginosa, LasR and RhlR are homologous LuxR-type soluble transcription factor receptors that bind their cognate AIs and activate the expression of genes encoding functions required for virulence and biofilm formation. While some bacterial signal transduction pathways follow a linear circuit, as phosphoryl groups are passed from one carrier protein to another ultimately resulting in up- or down-regulation of target genes, the QS system in P. aeruginosa is a dense network of receptors and regulators with interconnecting regulatory systems and outputs. Once activated, it is not understood how LasR and RhlR establish their signaling hierarchy, nor is it clear how these pathway connections are regulated, resulting in chronic infection. Here, we reviewed the mechanisms of QS progression as it relates to bacterial pathogenesis and antimicrobial resistance and tolerance.
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16
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Sandora N, Fitria NA, Kusuma TR, Winarno GA, Tanjunga SF, Wardhana A. Amnion bilayer for dressing and graft replacement for delayed grafting of full-thickness burns; A study in a rat model. PLoS One 2022; 17:e0262007. [PMID: 35061768 PMCID: PMC8782387 DOI: 10.1371/journal.pone.0262007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Accepted: 12/15/2021] [Indexed: 11/19/2022] Open
Abstract
Burn is a common case in developing countries, with over half of fire-related deaths reported in Southeast Asia and full-thickness burns as a high mortality risk. Human amnion has been used as a wound dressing for centuries. In this study, a decellularised amnion overlaid with fibrin, “amnion bilayer (AB),” was used as a dressing immediately after burn and as a graft to replace the scar in Sprague-Dawley rats subjected to full-thickness burn model. The aim was to observe whether amnion bilayer can reduce damages in third-grade burn when skin replacement is deemed impossible. The burn was induced using an electrical solder, heated for 5 mins, and contacted on the rat’s bare skin for 20 s. AB was applied as a (i) dressing immediately after induction and graft after eschar removal. Two groups (n = 6) were compared: AB and Sofra-Tulle ®, the National Hospital of Indonesia (NHI) protocol. Sections were stained with hematoxylin and eosin and Masson trichrome stains. Immunohistochemistry labelling was used to indicate scars (α-smooth muscle actin [α-SMA] and collagen-1) and angiogenesis (von Willebrand factor). Also, the macrophages inflammatory protein-3α (MIP-3α) indicates an early inflammatory process. The post dressing of the AB group demonstrated hair follicle remains and adipose tissue development. The NHI group appeared with a denatured matrix. Complete healing was seen in the AB group after 28 days with skin appendages similar to normal, while the NHI group showed no appendages in the centre of the actively inflamed area. The α-SMA was found in both groups. Collagen-1 was highly expressed in the NHI group, which led to a scar. Angiogenesis was found more in the AB group. The AB group had shown the capacity to accelerate complete healing and recover skin appendages better than the current protocol.
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Affiliation(s)
- Normalina Sandora
- Faculty of Medicine, Universitas Riau, Pekanbaru, Indonesia
- Indonesian Medical Education and Research Institute (IMERI), Jakarta, Indonesia
| | - Nur Amalina Fitria
- Indonesian Medical Education and Research Institute (IMERI), Jakarta, Indonesia
| | - Tyas Rahmah Kusuma
- Indonesian Medical Education and Research Institute (IMERI), Jakarta, Indonesia
| | - Gammaditya Adhibarata Winarno
- Burn Unit, Cipto Mangunkusumo National General Hospital, Jakarta, Indonesia
- Department of Surgery, Plastic and Reconstructive Surgery Division, Cipto Mangunkusumo National General Hospital, Jakarta, Indonesia
| | - Sanjaya Faisal Tanjunga
- Burn Unit, Cipto Mangunkusumo National General Hospital, Jakarta, Indonesia
- Department of Surgery, Plastic and Reconstructive Surgery Division, Cipto Mangunkusumo National General Hospital, Jakarta, Indonesia
| | - Aditya Wardhana
- Burn Unit, Cipto Mangunkusumo National General Hospital, Jakarta, Indonesia
- Department of Surgery, Plastic and Reconstructive Surgery Division, Cipto Mangunkusumo National General Hospital, Jakarta, Indonesia
- Faculty of Medicine, Universitas Indonesia, Jakarta, Indonesia
- * E-mail:
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17
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β-lactam Resistance in Pseudomonas aeruginosa: Current Status, Future Prospects. Pathogens 2021; 10:pathogens10121638. [PMID: 34959593 PMCID: PMC8706265 DOI: 10.3390/pathogens10121638] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 12/06/2021] [Accepted: 12/16/2021] [Indexed: 12/12/2022] Open
Abstract
Pseudomonas aeruginosa is a major opportunistic pathogen, causing a wide range of acute and chronic infections. β-lactam antibiotics including penicillins, carbapenems, monobactams, and cephalosporins play a key role in the treatment of P. aeruginosa infections. However, a significant number of isolates of these bacteria are resistant to β-lactams, complicating treatment of infections and leading to worse outcomes for patients. In this review, we summarize studies demonstrating the health and economic impacts associated with β-lactam-resistant P. aeruginosa. We then describe how β-lactams bind to and inhibit P. aeruginosa penicillin-binding proteins that are required for synthesis and remodelling of peptidoglycan. Resistance to β-lactams is multifactorial and can involve changes to a key target protein, penicillin-binding protein 3, that is essential for cell division; reduced uptake or increased efflux of β-lactams; degradation of β-lactam antibiotics by increased expression or altered substrate specificity of an AmpC β-lactamase, or by the acquisition of β-lactamases through horizontal gene transfer; and changes to biofilm formation and metabolism. The current understanding of these mechanisms is discussed. Lastly, important knowledge gaps are identified, and possible strategies for enhancing the effectiveness of β-lactam antibiotics in treating P. aeruginosa infections are considered.
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18
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Lei H, Zhao J, Ma X, Li H, Fan D. Antibacterial Dual Network Hydrogels for Sensing and Human Health Monitoring. Adv Healthc Mater 2021; 10:e2101089. [PMID: 34453781 DOI: 10.1002/adhm.202101089] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 08/20/2021] [Indexed: 12/13/2022]
Abstract
Polymer-based conductive hydrogels have the synergistic advantages of high conductivity and tissue-like properties, making them promising candidates for the construction of flexible electronic devices. However, conductive hydrogel materials can easily absorb microorganisms due to their high water content. To address the problem that conductive hydrogels are susceptible to infection by external pathogens when monitoring wounds and when used in implanted organs, tannic acid-borax (TA-B) complexes are introduced into classical dual network polyacrylamide/agarose (PAM/Agar) hydrogels to form PAM/Agar/TA-B hydrogel conductors. These hydrogels are antibacterial and have good mechanical properties, light transmission, electrical conductivity, and adhesion. TA-B increases the compressive stress of the PAM/Agar/TA-B hydrogel by 58.14% compared to a PAM/Agar hydrogel. The PAM/Agar/TA-B hydrogel can be used as an electronic conductor for electronic skin and wearable sensors. Outstanding biocompatibility allows the hydrogel to be used as a monitoring device at wounds to monitor heartbeat, skin wounds, and internal tissue status in real time. In summary, an antibacterial strain sensing matrix that is safe for human health monitoring is developed.
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Affiliation(s)
- Huan Lei
- Shaanxi Key Laboratory of Degradable Biomedical Materials Shaanxi R&D Center of Biomaterials and Fermentation Engineering Biotech. & Biomed. Research Institute Northwest University Taibai North Road 229 Xi'an Shaanxi 710069 China
| | - Jing Zhao
- Shaanxi Key Laboratory of Degradable Biomedical Materials Shaanxi R&D Center of Biomaterials and Fermentation Engineering Biotech. & Biomed. Research Institute Northwest University Taibai North Road 229 Xi'an Shaanxi 710069 China
| | - Xiaoxuan Ma
- Shaanxi Key Laboratory of Degradable Biomedical Materials Shaanxi R&D Center of Biomaterials and Fermentation Engineering Biotech. & Biomed. Research Institute Northwest University Taibai North Road 229 Xi'an Shaanxi 710069 China
| | - Hang Li
- Department of Dermatology Peking University First Hospital Xishiku Street No.8 Beijing 100034 China
| | - Daidi Fan
- Shaanxi Key Laboratory of Degradable Biomedical Materials Shaanxi R&D Center of Biomaterials and Fermentation Engineering Biotech. & Biomed. Research Institute Northwest University Taibai North Road 229 Xi'an Shaanxi 710069 China
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19
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Periodically Disturbing the Spatial Structure of Biofilms Can Affect the Production of an Essential Virulence Factor in Pseudomonas aeruginosa. mSystems 2021; 6:e0096121. [PMID: 34581603 PMCID: PMC8547473 DOI: 10.1128/msystems.00961-21] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Understanding the environmental factors that affect the production of virulence factors has major implications in evolution and medicine. While spatial structure is important in virulence factor production, observations of this relationship have occurred in undisturbed or continuously disturbed environments. However, natural environments are subject to periodic fluctuations, including changes in physical forces, which could alter the spatial structure of bacterial populations and impact virulence factor production. Using Pseudomonas aeruginosa PA14, we periodically applied a physical force to biofilms and examined production of pyoverdine. Intermediate frequencies of disturbance reduced the amount of pyoverdine produced compared to undisturbed or frequently disturbed conditions. To explore the generality of this finding, we examined how an intermediate disturbance frequency affected pyoverdine production in 21 different strains of P. aeruginosa. Periodic disturbance increased, decreased, or did not change the amount of pyoverdine produced relative to undisturbed populations. Mathematical modeling predicts that interactions between pyoverdine synthesis rate and biofilm density determine the amount of pyoverdine synthesized. When the pyoverdine synthesis rates are high, depletion of the biofilm due to disturbance reduces the accumulation of pyoverdine. At intermediate synthesis rates, production of pyoverdine increases during disturbance as bacteria dispersed into the planktonic state enjoy increased growth and pyoverdine production rates. At low synthesis rates, disturbance does not alter the amount of pyoverdine produced since disturbance-driven access to nutrients does not augment pyoverdine synthesis. Our results suggest that environmental conditions shape robustness in the production of virulence factors and may lead to novel approaches to treat infections. IMPORTANCE Virulence factors are required to cause infections. Previous work has shown that the spatial organization of a population, such as a biofilm, can increase the production of some virulence factors, including pyoverdine, which is produced by Pseudomonas aeruginosa. Pyoverdine is essential for the infection process, and reducing its production can limit infections. We have discovered that periodically changing the spatial structure of a biofilm of P. aeruginosa strain PA14 using a physical force can reduce the production of pyoverdine. A mathematical model suggests that this is due to the disruption of spatial organization. Using additional strains of P. aeruginosa isolated from patients and the environment, we use experiments and modeling to show that this reduction in pyoverdine is due to interactions between biofilm density and the synthesis rate of pyoverdine. Our results identify conditions where pyoverdine production is reduced and may lead to novel ways to treat infections.
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Khan F, Kang MG, Jo DM, Chandika P, Jung WK, Kang HW, Kim YM. Phloroglucinol-Gold and -Zinc Oxide Nanoparticles: Antibiofilm and Antivirulence Activities towards Pseudomonasaeruginosa PAO1. Mar Drugs 2021; 19:601. [PMID: 34822472 PMCID: PMC8624799 DOI: 10.3390/md19110601] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Revised: 10/12/2021] [Accepted: 10/21/2021] [Indexed: 12/23/2022] Open
Abstract
With the advancement of nanotechnology, several nanoparticles have been synthesized as antimicrobial agents by utilizing biologically derived materials. In most cases, the materials used for the synthesis of nanoparticles from natural sources are extracts. Natural extracts contain a wide range of bioactive components, making it difficult to pinpoint the exact component responsible for nanoparticle synthesis. Furthermore, the bioactive component present in the extract changes according to numerous environmental factors. As a result, the current work intended to synthesize gold (AuNPs) and zinc oxide (ZnONPs) nanoparticles using pure phloroglucinol (PG). The synthesized PG-AuNPs and PG-ZnONPs were characterized using a UV-Vis absorption spectrophotometer, FTIR, DLS, FE-TEM, zeta potential, EDS, and energy-dispersive X-ray diffraction. The characterized PG-AuNPs and PG-ZnONPs have been employed to combat the pathogenesis of Pseudomonas aeruginosa. P. aeruginosa is recognized as one of the most prevalent pathogens responsible for the common cause of nosocomial infection in humans. Antimicrobial resistance in P. aeruginosa has been linked to the development of recalcitrant phenotypic characteristics, such as biofilm, which has been identified as one of the major obstacles to antimicrobial therapy. Furthermore, P. aeruginosa generates various virulence factors that are a major cause of chronic infection. These PG-AuNPs and PG-ZnONPs significantly inhibit early stage biofilm and eradicate mature biofilm. Furthermore, these NPs reduce P. aeruginosa virulence factors such as pyoverdine, pyocyanin, protease, rhamnolipid, and hemolytic capabilities. In addition, these NPs significantly reduce P. aeruginosa swarming, swimming, and twitching motility. PG-AuNPs and PG-ZnONPs can be used as control agents for infections caused by the biofilm-forming human pathogenic bacterium P. aeruginosa.
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Affiliation(s)
- Fazlurrahman Khan
- Research Center for Marine Integrated Bionics Technology, Pukyong National University, Busan 48513, Korea; (F.K.); (W.-K.J.)
| | - Min-Gyun Kang
- Department of Food Science and Technology, Pukyong National University, Busan 48513, Korea; (M.-G.K.); (D.-M.J.)
| | - Du-Min Jo
- Department of Food Science and Technology, Pukyong National University, Busan 48513, Korea; (M.-G.K.); (D.-M.J.)
| | - Pathum Chandika
- Department of Biomedical Engineering and New-Senior Healthcare Innovation Center (BK21 Plus), Pukyong National University, Busan 48513, Korea;
| | - Won-Kyo Jung
- Research Center for Marine Integrated Bionics Technology, Pukyong National University, Busan 48513, Korea; (F.K.); (W.-K.J.)
- Department of Biomedical Engineering and New-Senior Healthcare Innovation Center (BK21 Plus), Pukyong National University, Busan 48513, Korea;
| | - Hyun Wook Kang
- Department of Biomedical Engineering, Pukyong National University, Busan 48513, Korea;
- Industry 4.0 Convergence Bionics Engineering, Pukyong National University, Busan 48513, Korea
| | - Young-Mog Kim
- Research Center for Marine Integrated Bionics Technology, Pukyong National University, Busan 48513, Korea; (F.K.); (W.-K.J.)
- Department of Food Science and Technology, Pukyong National University, Busan 48513, Korea; (M.-G.K.); (D.-M.J.)
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21
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D'Arpa P, Karna SLR, Chen T, Leung KP. Pseudomonas aeruginosa transcriptome adaptations from colonization to biofilm infection of skin wounds. Sci Rep 2021; 11:20632. [PMID: 34667187 PMCID: PMC8526614 DOI: 10.1038/s41598-021-00073-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Accepted: 09/07/2021] [Indexed: 11/09/2022] Open
Abstract
In burn patients Pseudomonas aeruginosa infection is a major cause of morbidity. Analysis of the pathogen's gene expression as it transitions from colonization to acute and then biofilm wound infection may provide strategies for infection control. Toward this goal, we seeded log-phase P. aeruginosa (PAO1) into 3-day-old, full-thickness excision wounds (rabbit ear) and harvested the bacteria during colonization (Hrs 2 and 6), acute infection (Hr 24), and biofilm infection (Days 5 and 9) for transcriptome analysis (RNA-Seq). After 2-6 h in the wound, genes for metabolism and cell replication were down-regulated while wound-adaptation genes were up-regulated (vs. expression in log-phase culture). As the infection progressed from acute to biofilm infection, more genes became up-regulated than down-regulated, but the down-regulated genes enriched in more pathways, likely because the genes and pathways that bacteria already colonizing wounds up-regulate to establish biofilm infection are less known. Across the stages of infection, carbon-utilization pathways shifted. During acute infection, itaconate produced by myeloid cells appears to have been a carbon source because myeloid cell infiltration and the expression of the host gene, ACOD1, for itaconate production peaked coincidently with the expression of the PAO1 genes for itaconate transport and catabolism. Additionally, branched-chain amino acids are suggested to be a carbon source in acute infection and in biofilm infection. In biofilm infection, fatty acid degradation was also up-regulated. These carbon sources feed into the glyoxylate cycle that was coincidently up-regulated, suggesting it provided the precursors for P. aeruginosa to synthesize macromolecules in establishing wound infection.
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Affiliation(s)
- Peter D'Arpa
- Combat Wound Repair Group and Tissue Regeneration Department, US Army Institute of Surgical Research, JBSA Fort Sam Houston, San Antonio, TX, USA.,The Geneva Foundation, Tacoma, USA
| | - S L Rajasekhar Karna
- Combat Wound Repair Group and Tissue Regeneration Department, US Army Institute of Surgical Research, JBSA Fort Sam Houston, San Antonio, TX, USA
| | - Tsute Chen
- The Forsyth Institute, Cambridge, MA, USA
| | - Kai P Leung
- Combat Wound Repair Group and Tissue Regeneration Department, US Army Institute of Surgical Research, JBSA Fort Sam Houston, San Antonio, TX, USA.
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Memar MY, Adibkia K, Farajnia S, Samadi Kafil H, Khalili Y, Azargun R, Ghotaslou R. In-vitro Effect of Imipenem, Fosfomycin, Colistin, and Gentamicin Combination against Carbapenem-resistant and Biofilm-forming Pseudomonas aeruginosa Isolated from Burn Patients. IRANIAN JOURNAL OF PHARMACEUTICAL RESEARCH : IJPR 2021; 20:286-296. [PMID: 34567162 PMCID: PMC8457740 DOI: 10.22037/ijpr.2020.111824.13380] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The aim of this study was to investigate in-vitro antibacterial and antibiofilm effect of colistin, imipenem, gentamicin, and fosfomycin alone and the various combinations against carbapenem-resistant Pseudomonas aeruginosa (P. aeruginosa). Eight carbapenem-resistant and biofilm-forming P. aeruginosa isolates from burn patients were collected. The mechanisms of resistance to carbapenem were determined by the phenotypic, PCR, and Real-Time PCR assays. The minimum inhibitory concentration (MIC) of antimicrobial agents was determined by the broth micro dilution. To detect any inhibitory effect of antibiotics against the biofilm, the biofilm inhibitory concentration was determined. To detect synergetic effects of the combinations of antibiotics, the checkerboard assay and the fractional inhibitory concentration (FIC) were used. The highest synergic effect was observed in colistin/fosfomycin and gentamicin/fosfomycin (5 of 8 isolates), and the lowest synergic effect was found in gentamicin/imipenem and colistin/gentamicin (1 of 8 isolates). Colistin/fosfomycin, imipenem/fosfomycin, colistin/imipenem, gentamicin/fosfomycin, and gentamicin/imipenem were shown synergic effect for 3, 2, 2, 2 and 1 isolates, respectively. The combination of antibiotics had different effects on biofilm and planktonic forms of P. aeruginosa. Therefore, a separate determination of inhibitory effects of the antibiotic in the combination is necessary. Fosfomycin/colistin and fosfomycin/gentamicin were more effective against planktonic form and fosfomycin/colistin against biofilm forms.
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Affiliation(s)
- Mohammad Yousef Memar
- Infectious and Tropical Diseases Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.,Department of Bacteriology and Virology, School of Medicine, Tabriz University of Medical Sciences, Iran
| | - Khosro Adibkia
- Research Center for Pharmaceutical Nanotechnology, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Safar Farajnia
- Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Hossein Samadi Kafil
- Department of Bacteriology and Virology, School of Medicine, Tabriz University of Medical Sciences, Iran.,Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Younes Khalili
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Robab Azargun
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Reza Ghotaslou
- Infectious and Tropical Diseases Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.,Department of Bacteriology and Virology, School of Medicine, Tabriz University of Medical Sciences, Iran
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23
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Burns and biofilms: priority pathogens and in vivo models. NPJ Biofilms Microbiomes 2021; 7:73. [PMID: 34504100 PMCID: PMC8429633 DOI: 10.1038/s41522-021-00243-2] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Accepted: 08/02/2021] [Indexed: 02/08/2023] Open
Abstract
Burn wounds can create significant damage to human skin, compromising one of the key barriers to infection. The leading cause of death among burn wound patients is infection. Even in the patients that survive, infections can be notoriously difficult to treat and can cause lasting damage, with delayed healing and prolonged hospital stays. Biofilm formation in the burn wound site is a major contributing factor to the failure of burn treatment regimens and mortality as a result of burn wound infection. Bacteria forming a biofilm or a bacterial community encased in a polysaccharide matrix are more resistant to disinfection, the rigors of the host immune system, and critically, more tolerant to antibiotics. Burn wound-associated biofilms are also thought to act as a launchpad for bacteria to establish deeper, systemic infection and ultimately bacteremia and sepsis. In this review, we discuss some of the leading burn wound pathogens and outline how they regulate biofilm formation in the burn wound microenvironment. We also discuss the new and emerging models that are available to study burn wound biofilm formation in vivo.
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Sakr MM, Elkhatib WF, Aboshanab KM, Mantawy EM, Yassien MA, Hassouna NA. In vivo evaluation of a recombinant N-acylhomoserine lactonase formulated in a hydrogel using a murine model infected with MDR Pseudomonas aeruginosa clinical isolate, CCASUP2. AMB Express 2021; 11:109. [PMID: 34313869 PMCID: PMC8316526 DOI: 10.1186/s13568-021-01269-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Accepted: 07/19/2021] [Indexed: 11/10/2022] Open
Abstract
Failure in the treatment of P. aeruginosa, due to its broad spectrum of resistance, has been associated with increased patient mortality. One alternative approach for infection control is quorum quenching which was found to decrease virulence of such pathogen. In this study, the efficiency of a recombinant Ahl-1 lactonase formulated as a hydrogel was investigated to control the infection of multidrug resistant (MDR) P. aeruginosa infected burn using a murine model. The recombinant N-acylhomoserine lactonase (Ahl-1) was formulated as a hydrogel. To test its ability to control the infection of MDR P. aeruginosa, a thermal injury model was used. Survival rate, and systemic spread of the infection were evaluated. Histopathological examination of the animal dorsal skin was also done for monitoring the healing and cellular changes at the site of infection. Survival rate in the treated group was 100% relative to 40% in the control group. A decrease of up to 3 logs of bacterial count in the blood samples of the treated animals relative to the control group and a decrease of up to 4 logs and 2.3 logs of bacteria in lung and liver samples, respectively were observed. Histopathological examination revealed more enhanced healing process in the treated group. Accordingly, by promoting healing of infected MDR P. aeruginosa burn and by reducing systemic spread of the infection as well as decreasing mortality rate, Ahl-1 hydrogel application is a promising strategy that can be used to combat and control P. aeruginosa burn infections.
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25
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Bhardwaj S, Bhatia S, Singh S, Franco Jr F. Growing emergence of drug-resistant Pseudomonas aeruginosa and attenuation of its virulence using quorum sensing inhibitors: A critical review. IRANIAN JOURNAL OF BASIC MEDICAL SCIENCES 2021; 24:699-719. [PMID: 34630947 PMCID: PMC8487598 DOI: 10.22038/ijbms.2021.49151.11254] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Accepted: 11/24/2020] [Indexed: 12/25/2022]
Abstract
A perilous increase in the number of bacterial infections has led to developing throngs of antibiotics for increasing the quality and expectancy of life. Pseudomonas aeruginosa is becoming resistant to all known conventional antimicrobial agents thereby posing a deadly threat to the human population. Nowadays, targeting virulence traits of infectious agents is an alternative approach to antimicrobials that is gaining much popularity to fight antimicrobial resistance. Quorum sensing (QS) involves interspecies communication via a chemical signaling pathway. Under this mechanism, cells work in a concerted manner, communicate with each other with the help of signaling molecules called auto-inducers (AI). The virulence of these strains is driven by genes, whose expression is regulated by AI, which in turn acts as transcriptional activators. Moreover, the problem of antibiotic-resistance in case of infections caused by P. aeruginosa becomes more alarming among immune-compromised patients, where the infectious agents easily take over the cellular machinery of the host while hidden in the QS mediated biofilms. Inhibition of the QS circuit of P. aeruginosa by targeting various signaling pathways such as LasR, RhlR, Pqs, and QScR transcriptional proteins will help in blocking downstream signal transducers which could result in reducing the bacterial virulence. The anti-virulence agent does not pose an immediate selective pressure on growing bacterium and thus reduces the pathogenicity without harming the target species. Here, we review exclusively, the growing emergence of multi-drug resistant (MDR) P. aeruginosa and the critical literature survey of QS inhibitors with their potential application of blocking P. aeruginosa infections.
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Affiliation(s)
- Snigdha Bhardwaj
- Department of Pharmaceutical Science, SHALOM Institute of Health and Allied Sciences, Sam Higginbottom University of Agriculture, Technology and Sciences (SHUATS), Naini, Prayagraj, India
| | - Sonam Bhatia
- Department of Pharmaceutical Science, SHALOM Institute of Health and Allied Sciences, Sam Higginbottom University of Agriculture, Technology and Sciences (SHUATS), Naini, Prayagraj, India
| | - Shaminder Singh
- Regional Centre for Biotechnology, NCR Biotech Science Cluster, 3rd Milestone, Faridabad-Gurugram Expressway, Faridabad - 121 001, Haryana, India
| | - Francisco Franco Jr
- Department of Chemistry, De La Salle University, Manila, Metro Manila, Philippines
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26
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Chen H, Yang L, Cheng L, Hu XH, Shen YM. Distribution and drug resistance of pathogens in burn patients in China from 2006 to 2019. World J Clin Cases 2021; 9:2228-2237. [PMID: 33869598 PMCID: PMC8026851 DOI: 10.12998/wjcc.v9.i10.2228] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 01/31/2021] [Accepted: 02/25/2021] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND In this study, recent trends in the distribution and drug resistance of pathogenic bacteria isolated from patients treated at a burn ward between 2006 and 2019 were investigated.
AIM To develop more effective clinical strategies and techniques for the prevention and treatment of bacterial infections in burn patients.
METHODS Clinical samples with positive bacteria were collected from patients at the burn ward in Beijing Jishuitan Hospital in China between January 2006 and December 2019. The samples were retrospectively analyzed, the distribution of pathogenic bacteria was determined, and the trends and changes in bacterial drug resistance during different period were assessed. Drug resistance in several main pathogenic bacteria from 2006 to 2011 and from 2012 to 2019 was comparatively summarized and analyzed.
RESULTS Samples from 17119 patients were collected and analyzed from 2006 to 2019. Surprisingly, a total of 7960 strains of different pathogenic bacteria were isolated at this hospital. Among these bacteria, 87.98% (7003/7960) of the strains were isolated from burn wounds, and only 1.34% (107/7960) were isolated from the blood of patients. In addition, 49.70% (3956/7960) were identified as Gram-positive bacteria, 48.13% (3831/7960) were Gram-negative bacteria, and the remaining 2.17% (173/7960) were classified as fungi or other pathogens. Importantly, Staphylococcus aureus (21.68%), Pseudomonas aeruginosa (14.23%), and Staphylococcus epidermidis (9.61%) were the top three pathogens most frequently isolated from patients.
CONCLUSION In patients treated at the burn ward in this hospital from 2006 to 2019, Staphylococcus aureus and Pseudomonas aeruginosa were the predominant clinical pathogens responsible for bacterial infections. The circumstantial detection and detailed monitoring of the intensity and growth of different pathogenic bacteria in clinical patients as well as tests of drug sensitivity during burn recovery are particularly important to provide guidelines for the application of antibiotics and other related drugs. Careful collection and correct, standard culture of bacterial specimens are also crucial to improve the efficiency of bacterial infection detection. Effective monitoring and timely clinical treatment in patients may help reduce the possibility and rate of infection as well as alleviate the effects of drug resistance among patients in burn centers.
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Affiliation(s)
- Hui Chen
- Department of Burns and Plastic Surgery, Beijing Jishuitan Hospital, Beijing 100035, China
| | - Lin Yang
- Department of Healthcare Associated Infection Control, Beijing Jishuitan Hospital, Beijing 100035, China
| | - Lin Cheng
- Department of Burns and Plastic Surgery, Beijing Jishuitan Hospital, Beijing 100035, China
| | - Xiao-Hua Hu
- Department of Burns and Plastic Surgery, Beijing Jishuitan Hospital, Beijing 100035, China
| | - Yu-Ming Shen
- Department of Burns and Plastic Surgery, Beijing Jishuitan Hospital, Beijing 100035, China
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27
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Memar MY, Yekani M, Ghanbari H, Nabizadeh E, Vahed SZ, Dizaj SM, Sharifi S. Antimicrobial and antibiofilm activities of meropenem loaded-mesoporous silica nanoparticles against carbapenem-resistant Pseudomonas aeruginosa. J Biomater Appl 2021; 36:605-612. [PMID: 33722086 DOI: 10.1177/08853282211003848] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The aims of the present study were the determination of antimicrobial and antibiofilm effects of meropenem-loaded mesoporous silica nanoparticles (MSNs) on carbapenem resistant Pseudomonas aeruginosa (P. aeruginosa) and cytotoxicity properties in vitro. The meropenem-loaded MSNs had shown antibacterial and biofilm inhibitory activities on all isolates at different levels lower than MICs and BICs of meropenem. The viability of HC-04 cells treated with serial concentrations as MICs and BICs of meropenem-loaded MSNs was 92-100%. According to the obtained results, meropenem-loaded MSNs display the significant antibacterial and antibiofilm effects against carbapenem resistant and biofilm forming P. aeruginosa and low cell toxicity in vitro. Then, the prepared system can be an appropriate option for the delivery of carbapenem for further evaluation in vivo assays.
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Affiliation(s)
- Mohammad Yousef Memar
- Infectious and Tropical Diseases Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mina Yekani
- Department of Microbiology, Faculty of Medicine, Kashan University of Medical Sciences, Kashan, Iran.,Student Research Committee, Kashan University of Medical Sciences, Kashan, Iran
| | - Hadi Ghanbari
- Department of Pharmacognosy, Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Edris Nabizadeh
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | | | - Solmaz Maleki Dizaj
- Dental and Periodontal Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Simin Sharifi
- Dental and Periodontal Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
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In silico analysis of STX2a-PE15-P4A8 chimeric protein as a novel immunotoxin for cancer therapy. In Silico Pharmacol 2021; 9:19. [PMID: 33643767 DOI: 10.1007/s40203-021-00079-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Accepted: 01/19/2021] [Indexed: 10/25/2022] Open
Abstract
Today, the targeted therapies like the use of immunotoxins are increased which targeted specific antigens or receptors on the surface of tumor cells. Fibroblast growth factor-inducible 14 (Fn14) is a cytokine receptor which involves several intercellular signaling pathways and can be highly expressed in the surface of cancer cells. Since the cleavage of enzymatic domain of Pseudomonas exotoxin A (PE) occurs in one step by furin protease, we fused enzymatic subunit of Shiga-like toxin type 2a (Stx2a) with domain II and a portion of Ib of PE to increase the toxicity of Stx. Then, we genetically fused the Fv fragment of an anti-Fn14 monoclonal antibody (P4A8) to STX2a-PE15 and evaluated the STX2a-PE15-P4A8 chimeric protein as a new immunotoxin candidate. In silico analysis showed that the STX2a-PE15-P4A8 is a stable chimeric protein with high affinity to the Fn14 receptor. Despite, the STX2a-PE15-P4A8 can be bind to the B cell receptor, but it has been weakly presented by major histocompatibility complex molecules II (MHC-II). So, it may have a little immunogenicity. On the basis of our in-silico studies we predict that STX2a-PE15-P4A8 can be a good candidate for cancer immunotherapy. Supplementary Information The online version contains supplementary material available at 10.1007/s40203-021-00079-w.
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Zhang P, Zou B, Liou YC, Huang C. The pathogenesis and diagnosis of sepsis post burn injury. BURNS & TRAUMA 2021; 9:tkaa047. [PMID: 33654698 PMCID: PMC7901709 DOI: 10.1093/burnst/tkaa047] [Citation(s) in RCA: 57] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 10/20/2020] [Indexed: 02/05/2023]
Abstract
Burn is an under-appreciated trauma that is associated with unacceptably high morbidity and mortality. Although the survival rate after devastating burn injuries has continued to increase in previous decades due to medical advances in burn wound care, nutritional and fluid resuscitation and improved infection control practices, there are still large numbers of patients at a high risk of death. One of the most common complications of burn is sepsis, which is defined as “severe organ dysfunction attributed to host's disordered response to infection” and is the primary cause of death in burn patients. Indeed, burn injuries are accompanied by a series of events that lead to sepsis and multiple organ dysfunction syndrome, such as a hypovolaemic state, immune and inflammatory responses and metabolic changes. Therefore, clear diagnostic criteria and predictive biomarkers are especially important in the prevention and treatment of sepsis and septic shock. In this review, we focus on the pathogenesis of burn wound infection and the post-burn events leading to sepsis. Moreover, the clinical and promising biomarkers of burn sepsis will also be summarized.
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Affiliation(s)
- Pengju Zhang
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, and West China School of Basic Medical Sciences & Forensic Medicine, Sichuan University, and Collaborative Innovation Center for Biotherapy, No.17 People's South Road, Chengdu, 610041, China
| | - Bingwen Zou
- Department of Thoracic Oncology and Department of Radiation Oncology, Cancer Center, West China Hospital, Sichuan University, No.37 Guoxue Alley, Wuhou District, Chengdu, 610041, China
| | - Yih-Cherng Liou
- Department of Biological Sciences, Faculty of Science, National University of Singapore, 14 Science Drive 4, 117543, Singapore
| | - Canhua Huang
- State Key Laboratory of Biotherapy and Cancer Center, West China Hospital, and West China School of Basic Medical Sciences & Forensic Medicine, Sichuan University, and Collaborative Innovation Center for Biotherapy, No.17 People's South Road, Chengdu, 610041, China
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30
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Ladhani HA, Yowler CJ, Claridge JA. Burn Wound Colonization, Infection, and Sepsis. Surg Infect (Larchmt) 2020; 22:44-48. [PMID: 33085576 DOI: 10.1089/sur.2020.346] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
Background: Infection is a major cause of morbidity and mortality among burn patients, and it is important to understand the progression of wound colonization to wound infection to systemic sepsis. Methods: After a review of the literature we describe the clinical characteristics of burn wound colonization, infection, and sepsis, and conclude with best practices to decrease these complications. Results: Burn wounds are initially sterile after the thermal insult but become colonized by gram-positive organisms and subsequently by gram-negative organisms. Some populations are especially susceptible to initial or subsequent colonization by drug-resistant organisms. An increase in fungal colonization has been observed because of the widespread use of topical antibiotic agents. Male gender, older age, lower extremity burn, scald burn, full-thickness burn, delay in treatment, and pre-existing diabetes place patients at increased risk of infection. These infections range from cellulitis that requires systemic antibiotic agents, to invasive burn wound infection that requires prompt treatment with antibiotic agents and excision. Fungal wound infections pose a special challenge and cause substantial morbidity. Infection that leads to systemic sepsis is difficult to define in burn patients because of the body's compensatory hypermetabolic response to the burn injury. Potential sources of sepsis include wound infections and common nosocomial infections. The American Burn Association Sepsis criteria, defined in 2007, has demonstrated poor specificity for identifying sepsis and septic shock. The best approach to decrease wound infections is prevention. Practices that have been beneficial include isolation rooms, handwashing, appropriate wound care, early excision and grafting, antibiotic stewardship, and nutritional support. Conclusions: A burn patient remains at a substantial risk of wound infection despite advances in care. A burn care provider must understand the natural progression of colonization to infection to sepsis, and the multidisciplinary approach to wound care to limit the morbidity and mortality from these infectious.
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Affiliation(s)
- Husayn A Ladhani
- Department of Surgery, Division of Trauma, Critical Care, Burns, and Acute Care Surgery, Case Western Reserve University School of Medicine, MetroHealth Medical Center, Cleveland, Ohio, USA
| | - Charles J Yowler
- Department of Surgery, Division of Trauma, Critical Care, Burns, and Acute Care Surgery, Case Western Reserve University School of Medicine, MetroHealth Medical Center, Cleveland, Ohio, USA
| | - Jeffrey A Claridge
- Department of Surgery, Division of Trauma, Critical Care, Burns, and Acute Care Surgery, Case Western Reserve University School of Medicine, MetroHealth Medical Center, Cleveland, Ohio, USA
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Weaver AJ, Brandenburg KS, Sanjar F, Wells AR, Peacock TJ, Leung KP. Clinical Utility of PNA-FISH for Burn Wound Diagnostics: A Noninvasive, Culture-Independent Technique for Rapid Identification of Pathogenic Organisms in Burn Wounds. J Burn Care Res 2020; 40:464-470. [PMID: 30893424 PMCID: PMC6587406 DOI: 10.1093/jbcr/irz047] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Burn injury results in an immediate compromised skin state, which puts the affected patient at an immediate risk for infection, including sepsis. For burn patients that develop infections, it is critical to rapidly identify the etiology so that an appropriate treatment can be administered. Current clinical standards rely heavily on culture-based methods for local and systemic infection testing, which can often take days to complete. While more advanced methods (ie, MALDI or NAAT) have improved turnaround times, they may still suffer from either the need for pure culture or sensitivity and specificity issues. Peptide nucleic acid fluorescent in situ hybridization (PNA-FISH) offers a way to reduce this time from days to hours and provide species-specific identification. While PNA-FISH has had great utility in research, its use in clinical microbiology diagnostics has been minimal (including burn wound diagnostics). This work describes a nonculture-based identification technique using commercial available U.S. FDA-approved PNA-FISH probes for the identification of common clinical pathogens, Pseudomonas aeruginosa and Staphylococcus aureus, present in burn wound infections. Additionally, calcofluor white was included for identification of Candida albicans. All three pathogens were identified from a tri-species infected deep-partial thickness rat burn wound model. These species were clearly identifiable in swab and tissue samples that were collected, with minimal autofluorescence from any species. Although autofluorescence of the tissue was present, it did not interfere or was otherwise minimized through sample preparation and analysis. The methodology developed was done so with patient care and diagnostic laboratories in mind that it might be easily transferred to the clinical setting.
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Affiliation(s)
- Alan J Weaver
- Dental and Craniofacial Trauma Research and Tissue Regeneration Directorate, United States Army Institute of Surgical Research, JBSA, Fort Sam Houston, Texas
| | - Kenneth S Brandenburg
- Dental and Craniofacial Trauma Research and Tissue Regeneration Directorate, United States Army Institute of Surgical Research, JBSA, Fort Sam Houston, Texas
| | - Fatemeh Sanjar
- Dental and Craniofacial Trauma Research and Tissue Regeneration Directorate, United States Army Institute of Surgical Research, JBSA, Fort Sam Houston, Texas
| | - Adrienne R Wells
- Dental and Craniofacial Trauma Research and Tissue Regeneration Directorate, United States Army Institute of Surgical Research, JBSA, Fort Sam Houston, Texas
| | | | - Kai P Leung
- Dental and Craniofacial Trauma Research and Tissue Regeneration Directorate, United States Army Institute of Surgical Research, JBSA, Fort Sam Houston, Texas
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Maslova E, Shi Y, Sjöberg F, Azevedo HS, Wareham DW, McCarthy RR. An Invertebrate Burn Wound Model That Recapitulates the Hallmarks of Burn Trauma and Infection Seen in Mammalian Models. Front Microbiol 2020; 11:998. [PMID: 32582051 PMCID: PMC7283582 DOI: 10.3389/fmicb.2020.00998] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Accepted: 04/24/2020] [Indexed: 11/13/2022] Open
Abstract
The primary reason for skin graft failure and the mortality of burn wound patients, particularly those in burn intensive care centers, is bacterial infection. Several animal models exist to study burn wound pathogens. The most commonly used model is the mouse, which can be used to study virulence determinants and pathogenicity of a wide range of clinically relevant burn wound pathogens. However, animal models of burn wound pathogenicity are governed by strict ethical guidelines and hindered by high levels of animal suffering and the high level of training that is required to achieve consistent reproducible results. In this study, we describe for the first time an invertebrate model of burn trauma and concomitant wound infection. We demonstrate that this model recapitulates many of the hallmarks of burn trauma and wound infection seen in mammalian models and in human patients. We outline how this model can be used to discriminate between high and low pathogenicity strains of two of the most common burn wound colonizers Pseudomonas aeruginosa and Staphylococcus aureus, and multi-drug resistant Acinetobacter baumannii. This model is less ethically challenging than traditional vertebrate burn wound models and has the capacity to enable experiments such as high throughput screening of both anti-infective compounds and genetic mutant libraries.
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Affiliation(s)
- Evgenia Maslova
- Division of Biosciences, Centre for Inflammation Research and Translational Medicine, Department of Life Sciences, College of Health and Life Sciences, Brunel University London, London, United Kingdom
| | - Yejiao Shi
- School of Engineering and Materials Science, Institute of Bioengineering, Queen Mary, University of London, London, United Kingdom
| | - Folke Sjöberg
- The Burn Centre, Department of Hand and Plastic Surgery, Linköping University, Linköping, Sweden.,Department of Clinical and Experimental Medicine, Faculty of Health Sciences, Linköping University, Linköping, Sweden
| | - Helena S Azevedo
- School of Engineering and Materials Science, Institute of Bioengineering, Queen Mary, University of London, London, United Kingdom
| | - David W Wareham
- Antimicrobial Research Group, Blizard Institute, Queen Mary, University of London, London, United Kingdom
| | - Ronan R McCarthy
- Division of Biosciences, Centre for Inflammation Research and Translational Medicine, Department of Life Sciences, College of Health and Life Sciences, Brunel University London, London, United Kingdom
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Secor PR, Burgener EB, Kinnersley M, Jennings LK, Roman-Cruz V, Popescu M, Van Belleghem JD, Haddock N, Copeland C, Michaels LA, de Vries CR, Chen Q, Pourtois J, Wheeler TJ, Milla CE, Bollyky PL. Pf Bacteriophage and Their Impact on Pseudomonas Virulence, Mammalian Immunity, and Chronic Infections. Front Immunol 2020; 11:244. [PMID: 32153575 PMCID: PMC7047154 DOI: 10.3389/fimmu.2020.00244] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Accepted: 01/30/2020] [Indexed: 12/11/2022] Open
Abstract
Pf bacteriophage are temperate phages that infect the bacterium Pseudomonas aeruginosa, a major cause of chronic lung infections in cystic fibrosis (CF) and other settings. Pf and other temperate phages have evolved complex, mutualistic relationships with their bacterial hosts that impact both bacterial phenotypes and chronic infection. We and others have reported that Pf phages are a virulence factor that promote the pathogenesis of P. aeruginosa infections in animal models and are associated with worse skin and lung infections in humans. Here we review the biology of Pf phage and what is known about its contributions to pathogenesis and clinical disease. First, we review the structure, genetics, and epidemiology of Pf phage. Next, we address the diverse and surprising ways that Pf phages contribute to P. aeruginosa phenotypes including effects on biofilm formation, antibiotic resistance, and motility. Then, we cover data indicating that Pf phages suppress mammalian immunity at sites of bacterial infection. Finally, we discuss recent literature implicating Pf in chronic P. aeruginosa infections in CF and other settings. Together, these reports suggest that Pf bacteriophage have direct effects on P. aeruginosa infections and that temperate phages are an exciting frontier in microbiology, immunology, and human health.
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Affiliation(s)
- Patrick R. Secor
- Division of Biological Sciences, University of Montana, Missoula, MT, United States
- Center for Translational Medicine, University of Montana, Missoula, MT, United States
- Center for Biomolecular Structure and Dynamics, University of Montana, Missoula, MT, United States
| | - Elizabeth B. Burgener
- Department of Pediatrics, Center for Excellence in Pulmonary Biology, Stanford University, Stanford, CA, United States
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA, United States
| | - M. Kinnersley
- Division of Biological Sciences, University of Montana, Missoula, MT, United States
| | - Laura K. Jennings
- Division of Biological Sciences, University of Montana, Missoula, MT, United States
- Center for Translational Medicine, University of Montana, Missoula, MT, United States
| | - Valery Roman-Cruz
- Division of Biological Sciences, University of Montana, Missoula, MT, United States
- Center for Translational Medicine, University of Montana, Missoula, MT, United States
| | - Medeea Popescu
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA, United States
| | - Jonas D. Van Belleghem
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA, United States
| | - Naomi Haddock
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA, United States
| | - Conner Copeland
- Department of Computer Science, University of Montana, Missoula, MT, United States
| | - Lia A. Michaels
- Division of Biological Sciences, University of Montana, Missoula, MT, United States
| | - Christiaan R. de Vries
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA, United States
| | - Qingquan Chen
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA, United States
| | - Julie Pourtois
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA, United States
| | - Travis J. Wheeler
- Center for Biomolecular Structure and Dynamics, University of Montana, Missoula, MT, United States
- Department of Computer Science, University of Montana, Missoula, MT, United States
| | - Carlos E. Milla
- Department of Pediatrics, Center for Excellence in Pulmonary Biology, Stanford University, Stanford, CA, United States
| | - Paul L. Bollyky
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, CA, United States
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Sweere JM, Ishak H, Sunkari V, Bach MS, Manasherob R, Yadava K, Ruppert SM, Sen CK, Balaji S, Keswani SG, Secor PR, Bollyky PL. The Immune Response to Chronic Pseudomonas aeruginosa Wound Infection in Immunocompetent Mice. Adv Wound Care (New Rochelle) 2020; 9:35-47. [PMID: 31903297 PMCID: PMC6940591 DOI: 10.1089/wound.2019.1039] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 06/27/2019] [Indexed: 12/16/2022] Open
Abstract
Objective: Our goal was to develop a chronic wound model in mice that avoids implantation of foreign material or impaired immunity and to use this to characterize the local and systemic immune response associated with Pseudomonas aeruginosa infection. Approach: We generated bilateral full-thickness dermal wounds in healthy 10-12-week-old C57Bl6 mice. We waited 24 h to inoculate the developing wound eschar at these sites. We performed careful titration experiments with luminescent strains of P. aeruginosa to identify bacterial inoculation concentrations that consistently established stable infections in these animals. We performed flow cytometry-based immunophenotyping of immune cell infiltrates at the wound site, spleen, and draining lymph nodes over time. Finally, we compared inflammatory responses seen in wound inoculation with planktonic bacteria, preformed biofilm, and heat-killed (HK) P. aeruginosa. Results: Using this delayed inoculation model and 7.5 ± 2.5 × 102 CFU/mL of PAO1 we consistently established stable infections that lasted at 10 days in duration. During early infection, we detected a strong upregulation of inflammatory cytokines and neutrophil infiltration at the wound site, while natural killer (NK) cells and dendritic cells (DCs) were reduced. At the systemic level, only plasmacytoid DCs were increased early in infection. During later stages, there was systemic upregulation of B cells, T cells, and macrophages, whereas NK cells and interferon killer DCs were reduced. Infections with P. aeruginosa biofilms were not more virulent than infections with planktonic P. aeruginosa, whereas treatment with HK P. aeruginosa only induces a short-term inflammatory state. Innovation: We describe a versatile wound model of chronic P. aeruginosa infection that lasts 10 days without causing sepsis or other excessive morbidity. Conclusion: This model may facilitate the study of chronic wound infections in immunocompetent mice. Our findings also highlight the induction of early innate immune cell populations during P. aeruginosa infection.
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Affiliation(s)
- Johanna M. Sweere
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, California
- Stanford Immunology, Stanford University, Stanford, California
| | - Heather Ishak
- Department of Neurology, Palo Alto Veterans Institute of Research, Palo Alto, California
| | - Vivekananda Sunkari
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, California
| | - Michelle S. Bach
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, California
| | - Robert Manasherob
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, California
| | - Koshika Yadava
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, California
- Medical Sciences Division, University of Oxford, Oxford, United Kingdom
| | - Shannon M. Ruppert
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, California
| | - Chandan K. Sen
- Department of Surgery, Indiana University School of Medicine, Indiana University, Bloomington, Indiana
| | - Swathi Balaji
- Division of Pediatric Surgery, Department of Surgery, Baylor College of Medicine, Houston, Texas
| | - Sundeep G. Keswani
- Division of Pediatric Surgery, Department of Surgery, Baylor College of Medicine, Houston, Texas
| | - Patrick R. Secor
- Division of Biological Sciences, University of Montana, Missoula, Montana
| | - Paul L. Bollyky
- Division of Infectious Diseases and Geographic Medicine, Department of Medicine, Stanford University, Stanford, California
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Weaver AJ, Brandenburg KS, Smith BW, Leung KP. Comparative Analysis of the Host Response in a Rat Model of Deep-Partial and Full-Thickness Burn Wounds With Pseudomonas aeruginosa Infection. Front Cell Infect Microbiol 2020; 9:466. [PMID: 31998665 PMCID: PMC6967395 DOI: 10.3389/fcimb.2019.00466] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2019] [Accepted: 12/17/2019] [Indexed: 12/12/2022] Open
Abstract
Burn wound injury affects soldiers and civilians alike, often resulting in a dynamic, but un-orchestrated, host response that can lead to infection, scarring, and potentially death. To mitigate these factors, it is important to have a clinically relevant model of burn wound infection that can be utilized for advancing burn wound treatments. Our previous reports have demonstrated the ability of Pseudomonas aeruginosa to generate a biofilm infection within a modified Walker-Mason rat burn model of deep-partial (DPT) and full-thickness (FT) burn wounds (10% total body surface area) in male Sprague-Dawley rats (350–450 g). Here, we further define this model with respect to the host response when challenged with P. aeruginosa infection between the two burn types. Following burn injury and immediate surface exposure to P. aeruginosa, inflammation at the local and systemic levels were monitored for an 11 days period. Compared to burn-only groups, infection with P. aeruginosa further promoted local inflammation in both DPT and FT burn wounds, which was evident by enhanced cellular influx (including neutrophils and monocytes), increased levels of several pro-inflammatory cytokines (IL-1β, IL-6, GRO/KC, andMIP-1α), and reduced IL-10. Systemically, only minor changes were seen in circulating white blood cells and cytokines; however, increases in high mobility group box-1 (HMGB-1) and hyaluronan, as well as decreases in fibronectin were noted particularly in FT burns. Compared to the burn-only group, P. aeruginosa infection resulted in sustained and/or higher levels of HMGB-1 and hyaluronan. Combined with our previous work that defined the burn depth and development of P. aeruginosa biofilms within the wound, this study further establishes this model by defining the host response to the burn and biofilm-infection. Furthermore, this characterization shows several similarities to what is clinically seen and establishes this model for future use in the development and testing of novel therapeutics for burn wound treatment at home and on the battlefield.
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Affiliation(s)
- Alan J Weaver
- Department of Dental and Craniofacial Trauma Research, United States Army Institute of Surgical Research, JBSA Fort Sam Houston, San Antonio, TX, United States
| | - Kenneth S Brandenburg
- Department of Dental and Craniofacial Trauma Research, United States Army Institute of Surgical Research, JBSA Fort Sam Houston, San Antonio, TX, United States
| | - Brian W Smith
- Research Support Division, United States Army Institute of Surgical Research, JBSA Fort Sam Houston, San Antonio, TX, United States
| | - Kai P Leung
- Department of Dental and Craniofacial Trauma Research, United States Army Institute of Surgical Research, JBSA Fort Sam Houston, San Antonio, TX, United States
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Pangli H, Papp A. The relation between positive screening results and MRSA infections in burn patients. Burns 2019; 45:1585-1592. [PMID: 31447204 DOI: 10.1016/j.burns.2019.02.023] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Revised: 01/21/2019] [Accepted: 02/27/2019] [Indexed: 11/28/2022]
Abstract
INTRODUCTION Methicillin-resistant Staphylococcus aureus (MRSA) is a key pathogen in burn patients. Several factors put them at increased risk of MRSA infection: partial loss of the skin barrier, the immune-compromising effects of burns, prolonged hospital stays, and invasive procedures. This study aims to find the relation between MRSA screening swab cultures taken within 48 h of admission, weekly surveillance cultures, and MRSA infection secondary to colonization. METHODS The data of all burns patients admitted to the referral centre for burns from 2012 to 2016 were reviewed. MRSA cultures taken at admission and on weekly surveillance screening, including nasal, perianal, and wound swabs, were reviewed. To determine associations between MRSA colonization and infection rates, both MRSA-positive and MRSA-negative swab cultures were included in the analysis. Several risk factors were considered: age, gender, ethnicity, %TBSA, BAUX index, inhalational injury, ICU admission and days, need for ventilator support and days, length of stay (LOS) in hospital, and complications. Univariate and multiple logistic regression analyses were used to predict correlations between positive swab cultures and risk factors. RESULTS Data from 396 patients were reviewed. The median age at admission for the burn patients was 46 (IQR: 31-59) years. On admission, 2.5% of patients were MRSA positive, whereas 17.9% were found to be MRSA positive on weekly surveillance screening. At surveillance, 60.6% developed an infection secondary to MRSA colonization. An MRSA infection was not identified for any patient who did not have at least one positive admission or surveillance swab. A statistically significant association was found between any positive swab and MRSA infection (P < 0.001). The median number of complications reported in the MRSA-positive group was 2 (IQR: 1-3) versus 0 (IQR: 0-1) in the MRSA-negative group and the median length of hospital stay in the MRSA-positive group was 34.5 (IQR: 20.25-56.25) days versus 7 (IQR: 3-16) days in the MRSA-negative group (P < 0.001). CONCLUSION Nosocomial MRSA colonization rates are high, and patients incurring infections experience a greater than average LOS in hospital and complications. Over 60% of patients who had a positive swab culture at surveillance developed an infection, whereas, no patient with a negative MRSA swab status developed an infection. Hence, pragmatic prevention strategies have to be implemented.
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Affiliation(s)
| | - Anthony Papp
- UBC Division of Plastic Surgery, Vancouver General Hospital, Vancouver, British Columbia, Canada
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Ziwa M, Jovic G, Ngwisha CLT, Molnar JA, Kwenda G, Samutela M, Mulowa M, Kalumbi MM. Common hydrotherapy practices and the prevalence of burn wound bacterial colonisation at the University Teaching Hospital in Lusaka, Zambia. Burns 2018; 45:983-989. [PMID: 30595542 DOI: 10.1016/j.burns.2018.11.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 11/25/2018] [Accepted: 11/30/2018] [Indexed: 11/19/2022]
Abstract
BACKGROUND In many parts of the world, hydrotherapy plays an important role in the management of patients with wounds including burns. Different centers practice hydrotherapy differently. At the University Teaching Hospital in Lusaka, Zambia, burn patients use a common bathtub for cleaning their wounds which theoretically increases the risk of cross-infection, an important source of morbidity and mortality. There is currently no evidence that hydrotherapy as practiced at our institution leads to cross infection among patients with burns. OBJECTIVE The objective was to determine if our hydrotherapy practice and water plays a role in cross-infection and what organisms cause this infection. METHODS This was a prospective analytical study. Patients meeting the selection criteria were recruited. Swabs from the burn wounds were collected on admission (day 0), day 4 and day 7. Weekly swabs of the bathtub were also collected, after the tub had been cleaned and declared ready for the next patient. Weekly water samples were also collected. Selected results, for Staphylococcus aureus and Klebsiella pneumoniae, were subjected to further analysis and PCR. Results were analyzed using statistics software, SPSS version 23. RESULTS In this study, there were 96 participants of which 51 (53.1%) were males and 45 (46.9%) were females. Age distribution ranged from 5months to 91 years. The modal age range was 1 to 2 years. The modal burn percentage was 6%-10%, followed by 11%-15%. Hot water was the cause of burns in 65.6%. S. aureus and K. pneumoniae were the most common organisms isolated. Others were enteric organisms. In terms of readily available antibiotics, there was more sensitivity to Amikacin and Chloramphenicol than Ciprofloxacin (our commonly used antibiotic). The bathtub also had S. aureus and K. pneumoniae, besides enteric organisms. Sixty five point four percent (65.4%) of the Klebsiella were ESBL (Extended Spectrum Beta Lactamase) producers. The tub had samples that were both ESBL producers as well as widely resistant Klebsiella by other means. No growth was obtained from the water samples. Seventy-two point nine percent (72.9%) of the patients were discharged, 19.8% died, while 7.3% left against medical advice. CONCLUSION Hydrotherapy as currently practiced at the University Teaching Hospital does contribute significantly to cross-infection among burn patients with widely resistant organisms. The main ones are S. aureus and K. pneumoniae. Switching care to a shower mechanism might help eliminate this problem as the study demonstrates that no bacteria were found in the water samples.
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Affiliation(s)
- Mudaniso Ziwa
- Department of Surgery, University of Zambia, School of Medicine, P. O. Box 50110, Lusaka, Zambia.
| | - Goran Jovic
- Department of Surgery, University of Zambia, School of Medicine, P. O. Box 50110, Lusaka, Zambia
| | - Chadwick L T Ngwisha
- Department of Surgery, University Teaching Hospital, Private Bag 1X RW, Lusaka, Zambia
| | - Joseph A Molnar
- Plastic and Reconstructive Surgery and Regenerative Medicine, Wake Forest University School of Medicine, Winston-Salem, NC, United States
| | - Geoffrey Kwenda
- Department of Biomedical Sciences, University of Zambia, School of Medicine, P. O. Box 50110, Lusaka, Zambia
| | - Mulemba Samutela
- Department of Biomedical Sciences, University of Zambia, School of Medicine, P. O. Box 50110, Lusaka, Zambia
| | - Mumbula Mulowa
- Department of Biomedical Sciences, University of Zambia, School of Medicine, P. O. Box 50110, Lusaka, Zambia
| | - Malama M Kalumbi
- Department of Pathology, University Teaching Hospital, Private Bag 1X RW, Lusaka, Zambia
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Olbrisch K, Kisch T, Thern J, Kramme E, Rupp J, Graf T, Wicha SG, Mailänder P, Raasch W. After standard dosage of piperacillin plasma concentrations of drug are subtherapeutic in burn patients. Naunyn Schmiedebergs Arch Pharmacol 2018; 392:229-241. [PMID: 30368548 DOI: 10.1007/s00210-018-1573-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Accepted: 10/19/2018] [Indexed: 12/21/2022]
Abstract
Infections are a major problem in patients with burn diseases. Mortality is high despite antibiotic therapy as studies are controversial concerning drug underdosing. The aims of this prospective, observational study were to monitor plasma concentrations of piperacillin during standard piperacillin/tazobactam treatment in 20 burn patients and 16 controls from the intensive care unit (ICU) and to optimize doses by in silico analyses. Piperacillin/tazobactam (4/0.5 g, tid) was administered over 0.5 h. Blood samples were taken at 1, 4, and 7.5 h after the end of the infusion. Free piperacillin plasma concentrations were determined. Pharmacokinetic parameters and in silico analysis results were calculated using the freeware TDMx. The primary target was defined as percentage of the day (fT>1xMIC; fT>4xMIC) when piperacillin concentrations exceeded 1xMIC/4xMIC (minimum inhibitory concentration), considering a MIC breakpoint of 16 mg/L for Pseudomonas aeruginosa. In an off-label approach, two burn patients were treated with 8/1 g piperacillin/tazobactam, 3 h qid. fT>1xMIC (55 ± 22% vs. 77 ± 24%) and fT>4xMIC (17 ± 11% vs. 30 ± 11%) were lower in burn than in ICU patients after 4/0.5 g, 0.5 h, tid. In silico analyses indicated that fT>1xMIC (93 ± 12% burn, 97 ± 4% ICU) and fT>4xMIC (62 ± 23% burn, 84 ± 19% ICU) values increase by raising the piperacillin dosage to 8/1 g qid and prolonging the infusion time to 3 h. Off-label treatment results were similar to in silico data for burn patients (84%fT>1xMIC and 47%fT>4xMIC). Standard dosage regimens for piperacillin/tazobactam resulted in subtherapeutic piperacillin concentrations in burn and ICU patients. Dose adjustments via in silico analyses can help to optimize antibiotic therapy and to predict respective concentrations in vivo. Trial registration: NCT03335137, registered 07.11.2017, retrospectively.
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Affiliation(s)
- Katharina Olbrisch
- Institute of Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, Lübeck, Germany
- Department of Pharmacy, University Hospital Schleswig-Holstein, Campus Lübeck, Lübeck, Germany
| | - Tobias Kisch
- Clinic of Plastic Surgery, University Hospital Schleswig-Holstein, Campus Lübeck, Lübeck, Germany
| | - Julia Thern
- Department of Pharmacy, University Hospital Schleswig-Holstein, Campus Lübeck, Lübeck, Germany
| | - Evelyn Kramme
- Department of Infectious Diseases and Microbiology, University Hospital Schleswig-Holstein, Campus Lübeck, Lübeck, Germany
| | - Jan Rupp
- Department of Infectious Diseases and Microbiology, University Hospital Schleswig-Holstein, Campus Lübeck, Lübeck, Germany
| | - Tobias Graf
- University Heart Centre Lübeck, Department of Cardiology, Angiology and Intensive Care Medicine, University Hospital Schleswig-Holstein, Campus Lübeck, Lübeck, Germany
| | - Sebastian G Wicha
- Clinical Pharmacy, Institute of Pharmacy, University of Hamburg, Hamburg, Germany
| | - Peter Mailänder
- Clinic of Plastic Surgery, University Hospital Schleswig-Holstein, Campus Lübeck, Lübeck, Germany
| | - Walter Raasch
- Institute of Experimental and Clinical Pharmacology and Toxicology, University of Lübeck, Lübeck, Germany.
- DZHK (German Centre for Cardiovascular Research), partner site Hamburg/Kiel/Lübeck, Lübeck, Germany.
- CBBM (Center of Brain, Behavior and Metabolism), University of Lübeck, Lübeck, Germany.
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Lin YW, Chen K, Wang J, Velkov T, Zhou QT, Li J. A Proof-of-Concept Study of the Efficacy of Systemically Administered Polymyxins in Mouse Burn Wound Infection Caused by Multidrug-Resistant Gram-Negative Pathogens. Antimicrob Agents Chemother 2018; 62:e02527-17. [PMID: 29439974 PMCID: PMC5923121 DOI: 10.1128/aac.02527-17] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Accepted: 02/08/2018] [Indexed: 01/14/2023] Open
Abstract
The efficacy of subcutaneously administered polymyxins against burn wound infections caused by Pseudomonas aeruginosa, Acinetobacter baumannii, and Klebsiella pneumoniae was examined in a murine infection model. Subcutaneously administered colistin and polymyxin B (30 mg/kg thrice daily) achieved a ≥2-log10 reduction in the bacterial load for P. aeruginosa and A. baumannii infections, whereas wound infections by K. pneumoniae were less responsive (<1-log10 reduction). This study highlights the potential therapeutic benefits of parenteral polymyxins for treating burn wound infections.
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Affiliation(s)
- Yu-Wei Lin
- Monash Biomedicine Discovery Institute, Department of Microbiology, Monash University, Clayton, Victoria, Australia
| | - Ke Chen
- Monash Biomedicine Discovery Institute, Department of Microbiology, Monash University, Clayton, Victoria, Australia
| | - Jiping Wang
- Monash Biomedicine Discovery Institute, Department of Microbiology, Monash University, Clayton, Victoria, Australia
| | - Tony Velkov
- Department of Pharmacology and Therapeutics, The University of Melbourne, Melbourne, Victoria, Australia
| | - Qi Tony Zhou
- Department of Industrial and Physical Pharmacy, College of Pharmacy, Purdue University, West Lafayette, Indiana, USA
| | - Jian Li
- Monash Biomedicine Discovery Institute, Department of Microbiology, Monash University, Clayton, Victoria, Australia
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40
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Santiveri CR, Sismaet HJ, Kimani M, Goluch ED. Electrochemical Detection of
Pseudomonas aeruginosa
in Polymicrobial Environments. ChemistrySelect 2018. [DOI: 10.1002/slct.201800569] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Clara Romero Santiveri
- Escola Tècnica Superior d'Enginyeria Química Universitat Rovira I Virgili Avinguda dels Països Catalans, 26 Tarragona 43007 Spain
| | - Hunter J. Sismaet
- Department of Chemical Engineering Northeastern University 360 Huntington Ave. Boston, MA 02115 USA
| | - Martin Kimani
- Department of Chemical Engineering Northeastern University 360 Huntington Ave. Boston, MA 02115 USA
| | - Edgar D. Goluch
- Department of Chemical Engineering Department of Biology Department of Bioengineering Department of Civil and Environmental Engineering Northeastern University 360 Huntington Ave. Boston, MA 02115 USA
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41
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The Microbial Endocrinology of Pseudomonas aeruginosa: Inflammatory and Immune Perspectives. Arch Immunol Ther Exp (Warsz) 2018. [PMID: 29541797 DOI: 10.1007/s00005-018-0510-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Pseudomonas aeruginosa is a major pathogen responsible for both acute and chronic infection. Known as a colonising pathogen of the cystic fibrosis (CF) lung, it is implicated in other settings such as bronchiectasis. It has the ability to cause acute disseminated or localised infection particularly in the immunocompromised. Human hormones have been highlighted as potential regulators of bacterial virulence through crosstalk between analogous "quorum sensing" (QS) systems present in the bacteria that respond to mammalian hormones. Pseudomonas aeruginosa is known to utilise interconnected QS systems to coordinate its virulence and evade various aspects of the host immune system activated in response to infection. Several human hormones demonstrate an influence on P. aeruginosa growth and virulence. This inter-kingdom signalling, termed "microbial endocrinology" has important implications for host-microbe interaction during infection and, potentially opens up novel avenues for therapeutic intervention. This phenomenon, supported by the existence of sexual dichotomies in both microbial infection and chronic lung diseases such as CF is potentially explained by sex hormones and their influence on the infective process. This review summarises our current understanding of the microbial endocrinology of P. aeruginosa, including its endogenous QS systems and their intersection with human endocrinology, pathogenesis of infection and the host immune system.
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42
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Ofir H, Shefler H, Kornhaber R, Cleary M, Harats M, Haik J. Purpose-built national burns center: The Israeli experience. Nurs Health Sci 2018; 20:255-263. [DOI: 10.1111/nhs.12405] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Revised: 11/20/2017] [Accepted: 11/22/2017] [Indexed: 12/01/2022]
Affiliation(s)
- Hagit Ofir
- Department of Plastic and Reconstructive Surgery; Sheba Medical Center; Tel Hashomer Israel
- Sackler School of Medicine; Tel Aviv University; Tel Aviv Israel
| | - Hadas Shefler
- Department of Plastic and Reconstructive Surgery; Sheba Medical Center; Tel Hashomer Israel
- Sackler School of Medicine; Tel Aviv University; Tel Aviv Israel
| | - Rachel Kornhaber
- Department of Plastic and Reconstructive Surgery; Sheba Medical Center; Tel Hashomer Israel
- School of Health Sciences, College of Health and Medicine; University of Tasmania; Sydney New South Wales Australia
| | - Michelle Cleary
- School of Health Sciences, College of Health and Medicine; University of Tasmania; Sydney New South Wales Australia
| | - Moti Harats
- Department of Plastic and Reconstructive Surgery; Sheba Medical Center; Tel Hashomer Israel
- Sackler School of Medicine; Tel Aviv University; Tel Aviv Israel
- University of Notre Dame Australia; Fremantle Western Australia Australia
| | - Josef Haik
- Department of Plastic and Reconstructive Surgery; Sheba Medical Center; Tel Hashomer Israel
- Sackler School of Medicine; Tel Aviv University; Tel Aviv Israel
- University of Notre Dame Australia; Fremantle Western Australia Australia
- Talpiot Leadership Program; Sheba Medical Center; Tel Hashomer Israel
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43
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Mirani B, Pagan E, Currie B, Siddiqui MA, Hosseinzadeh R, Mostafalu P, Zhang YS, Ghahary A, Akbari M. An Advanced Multifunctional Hydrogel-Based Dressing for Wound Monitoring and Drug Delivery. Adv Healthc Mater 2017; 6:10.1002/adhm.201700718. [PMID: 28944601 PMCID: PMC5845857 DOI: 10.1002/adhm.201700718] [Citation(s) in RCA: 131] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 07/19/2017] [Indexed: 11/08/2022]
Abstract
Wound management is a major global challenge and poses a significant financial burden to the healthcare system due to the rapid growth of chronic diseases such as diabetes, obesity, and aging population. The ability to detect pathogenic infections and release drug at the wound site is of the utmost importance to expedient patient care. Herein, this study presents an advanced multifunctional dressing (GelDerm) capable of colorimetric measurement of pH, an indicator of bacterial infection, and release of antibiotic agents at the wound site. This study demonstrates the ability of GelDerm to detect bacterial infections using in vitro and ex vivo tests with accuracies comparable to the commercially available systems. Wireless interfaces to digital image capture hardware such as smartphones serve as a means for quantitation and enable the patient to record the wound condition at home and relay the information to the healthcare personnel for following treatment strategies. Additionally, the dressing is integrated within commercially available patches and can be placed on the wound without chemical or physical irritation. This study demonstrates the ability of GelDerm to eradicate bacteria by the sustained release of antibiotics. The proposed technology holds great promise in managing chronic and acute injuries caused by trauma, surgery, or diabetes.
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Affiliation(s)
- Bahram Mirani
- Center for Advanced Materials and Related Technologies (CAMTEC), University of Victoria, Victoria, BC, V8P 5C2, Canada
- Center for Biomedical Research, University of Victoria, Victoria, BC, V8P 5C2, Canada
- Laboratory for Innovations in Microengineering (LiME), Department of Mechanical Engineering, University of Victoria, Victoria, BC, V8P 5C2, Canada
| | - Erik Pagan
- Laboratory for Innovations in Microengineering (LiME), Department of Mechanical Engineering, University of Victoria, Victoria, BC, V8P 5C2, Canada
| | - Barbara Currie
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, V8P 5C2, Canada
| | - Mohammad Ali Siddiqui
- Laboratory for Innovations in Microengineering (LiME), Department of Mechanical Engineering, University of Victoria, Victoria, BC, V8P 5C2, Canada
| | - Reihaneh Hosseinzadeh
- Center for Advanced Materials and Related Technologies (CAMTEC), University of Victoria, Victoria, BC, V8P 5C2, Canada
- Center for Biomedical Research, University of Victoria, Victoria, BC, V8P 5C2, Canada
- Laboratory for Innovations in Microengineering (LiME), Department of Mechanical Engineering, University of Victoria, Victoria, BC, V8P 5C2, Canada
| | - Pooria Mostafalu
- Division of Engineering Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Cambridge, MA, 02139, USA
| | - Yu Shrike Zhang
- Division of Engineering Medicine, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Cambridge, MA, 02139, USA
| | - Aziz Ghahary
- Division of Plastic Surgery, Department of Surgery, Faculty of Medicine, Vancouver, BC, V5Z 1M9, Canada
| | - Mohsen Akbari
- Center for Advanced Materials and Related Technologies (CAMTEC), University of Victoria, Victoria, BC, V8P 5C2, Canada
- Center for Biomedical Research, University of Victoria, Victoria, BC, V8P 5C2, Canada
- Laboratory for Innovations in Microengineering (LiME), Department of Mechanical Engineering, University of Victoria, Victoria, BC, V8P 5C2, Canada
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Witzgall F, Ewert W, Blankenfeldt W. Structures of the N-Terminal Domain of PqsA in Complex with Anthraniloyl- and 6-Fluoroanthraniloyl-AMP: Substrate Activation in Pseudomonas Quinolone Signal (PQS) Biosynthesis. Chembiochem 2017; 18:2045-2055. [PMID: 28834007 DOI: 10.1002/cbic.201700374] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Indexed: 12/16/2022]
Abstract
Pseudomonas aeruginosa, a prevalent pathogen in nosocomial infections and a major burden in cystic fibrosis, uses three interconnected quorum-sensing systems to coordinate virulence processes. At variance with other Gram-negative bacteria, one of these systems relies on 2-alkyl-4(1H)-quinolones (Pseudomonas quinolone signal, PQS) and might hence be an attractive target for new anti-infective agents. Here we report crystal structures of the N-terminal domain of anthranilate-CoA ligase PqsA, the first enzyme of PQS biosynthesis, in complex with anthraniloyl-AMP and with 6-fluoroanthraniloyl-AMP (6FABA-AMP) at 1.4 and 1.7 Å resolution. We find that PqsA belongs to an unrecognized subfamily of anthranilate-CoA ligases that recognize the amino group of anthranilate through a water-mediated hydrogen bond. The complex with 6FABA-AMP explains why 6FABA, an inhibitor of PQS biosynthesis, is a good substrate of PqsA. Together, our data might pave a way to new pathoblockers in P. aeruginosa infections.
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Affiliation(s)
- Florian Witzgall
- Structure and Function of Proteins, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124, Braunschweig, Germany
| | - Wiebke Ewert
- Structure and Function of Proteins, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124, Braunschweig, Germany.,Institut für Biophysikalische Chemie, Medizinische Hochschule Hannover, Carl-Neuberg-Strasse 1, 30625, Hannover, Germany
| | - Wulf Blankenfeldt
- Structure and Function of Proteins, Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124, Braunschweig, Germany.,Institut für Biochemie, Biotechnologie und Bioinformatik, Technische Universität Braunschweig, Spielmannstrasse 7, 38106, Braunschweig, Germany
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45
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Catechol-Based Hydrogel for Chemical Information Processing. Biomimetics (Basel) 2017; 2:biomimetics2030011. [PMID: 31105174 PMCID: PMC6352696 DOI: 10.3390/biomimetics2030011] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 06/21/2017] [Accepted: 06/23/2017] [Indexed: 01/23/2023] Open
Abstract
Catechols offer diverse properties and are used in biology to perform various functions that range from adhesion (e.g., mussel proteins) to neurotransmission (e.g., dopamine), and mimicking the capabilities of biological catechols have yielded important new materials (e.g., polydopamine). It is well known that catechols are also redox-active and we have observed that biomimetic catechol-modified chitosan films are redox-active and possess interesting molecular electronic properties. In particular, these films can accept, store and donate electrons, and thus offer redox-capacitor capabilities. We are enlisting these capabilities to bridge communication between biology and electronics. Specifically, we are investigating an interactive redox-probing approach to access redox-based chemical information and convert this information into an electrical modality that facilitates analysis by methods from signal processing. In this review, we describe the broad vision and then cite recent examples in which the catechol–chitosan redox-capacitor can assist in accessing and understanding chemical information. Further, this redox-capacitor can be coupled with synthetic biology to enhance the power of chemical information processing. Potentially, the progress with this biomimetic catechol–chitosan film may even help in understanding how biology uses the redox properties of catechols for redox signaling.
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46
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Lee C, Walker SAN, Walker SE, Seto W, Simor A, Jeschke M. A prospective study evaluating tobramycin pharmacokinetics and optimal once daily dosing in burn patients. Burns 2017. [PMID: 28647460 DOI: 10.1016/j.burns.2017.05.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
BACKGROUND Once-daily aminoglycoside dosing (ODA) is used in most patient populations to optimize antibacterial activity and reduce toxicity. Unfortunately, burn patients are excluded from ODA due to concerns over altered pharmacokinetics resulting in a shortened half-life and low peak aminoglycoside concentrations. Retrospective studies suggest that ODA may be appropriate if higher milligram/kilogram doses are used. However, no prospective clinical trials in burn patients exist to confirm these findings. OBJECTIVE To determine the adequacy of once daily tobramycin dosed at 10mg/kg in adult burn patients. METHODS This prospective single dose pharmacokinetic clinical trial was conducted at the Ross Tilley Burn Centre. Patients with a total burn surface area (TBSA) of <20% and creatinine clearance ≥50mL/min were eligible. A first-order one compartment model was used to determine the pharmacokinetic profile from 3 or 5 tobramycin levels over a 24h period per patient. Monte Carlo simulation (MCS) was performed to determine the probability of target level attainment. RESULTS The mean percent TBSA, partial, and full thickness burn were 10%, 6%, and 4%, respectively. Nine of the ten patients recruited achieved peak concentrations of ≥20mg/L (mean of 29.4±5.7mg/L) and all patients had a trough level ≤0.5mg/L. The mean half-life, volume of distribution, and clearance were 2.58h, 0.33L/kg, and 7.40L/h, respectively. The MCS determined probability of attaining target peak concentrations with the 10mg/kg dose was 97%, which almost doubled that predicted with the usual 7mg/kg dose. CONCLUSION Burn patients with adequate renal function and <20% TBSA are candidates for ODA. Tobramycin half-life was similar to healthy, non-burn patients. The larger than normal volume of distribution supports the use of the higher empiric dose of 10mg/kg total body or adjusted weight in non-obese and obese patients, respectively, with further dose adjustment based on therapeutic drug monitoring.
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Affiliation(s)
- Colin Lee
- Sunnybrook Health Sciences Centre (SHSC), Department of Pharmacy, Canada; University of Toronto, Leslie Dan Faculty of Pharmacy, Canada
| | - Sandra A N Walker
- Sunnybrook Health Sciences Centre (SHSC), Department of Pharmacy, Canada; University of Toronto, Leslie Dan Faculty of Pharmacy, Canada; SHSC, Division of Infectious Diseases, Canada; SHSC, Sunnybrook Research Institute, Canada.
| | - Scott E Walker
- Sunnybrook Health Sciences Centre (SHSC), Department of Pharmacy, Canada; University of Toronto, Leslie Dan Faculty of Pharmacy, Canada
| | - Winnie Seto
- University of Toronto, Leslie Dan Faculty of Pharmacy, Canada; Hospital for Sick Children (HSC), Department of Pharmacy, Canada
| | - Andrew Simor
- SHSC, Division of Infectious Diseases, Canada; SHSC, Sunnybrook Research Institute, Canada; University of Toronto, Faculty of Medicine, Canada
| | - Marc Jeschke
- University of Toronto, Faculty of Medicine, Canada; SHSC, Ross Tilley Burn Centre, Canada
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47
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Calum H, Høiby N, Moser C. Mouse Model of Burn Wound and Infection: Thermal (Hot Air) Lesion-Induced Immunosuppression. ACTA ACUST UNITED AC 2017. [DOI: 10.1002/cpmo.25] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- Henrik Calum
- Department of Clinical Microbiology, Hvidovre Hospital; Copenhagen Denmark
| | - Niels Høiby
- Department of Clinical Microbiology, Rigshospitalet; Copenhagen Denmark
| | - Claus Moser
- Department of Clinical Microbiology, Rigshospitalet; Copenhagen Denmark
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48
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Allegretta G, Maurer CK, Eberhard J, Maura D, Hartmann RW, Rahme L, Empting M. In-depth Profiling of MvfR-Regulated Small Molecules in Pseudomonas aeruginosa after Quorum Sensing Inhibitor Treatment. Front Microbiol 2017; 8:924. [PMID: 28596760 PMCID: PMC5442231 DOI: 10.3389/fmicb.2017.00924] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2017] [Accepted: 05/08/2017] [Indexed: 01/02/2023] Open
Abstract
Pseudomonas aeruginosa is a Gram-negative bacterium, which causes opportunistic infections in immuno-compromised individuals. Due to its multiple resistances toward antibiotics, the development of new drugs is required. Interfering with Quorum Sensing (QS), a cell-to-cell communication system, has shown to be highly efficient in reducing P. aeruginosa pathogenicity. One of its QS systems employs Pseudomonas Quinolone Signal (PQS) and 4-hydroxy-2-heptylquinoline (HHQ) as signal molecules. Both activate the transcriptional regulator MvfR (Multiple Virulence Factor Regulator), also called PqsR, driving the production of QS molecules as well as toxins and biofilm formation. The aim of this work was to elucidate the effects of QS inhibitors (QSIs), such as MvfR antagonists and PqsBC inhibitors, on the biosynthesis of the MvfR-regulated small molecules 2′-aminoacetophenone (2-AA), dihydroxyquinoline (DHQ), HHQ, PQS, and 4-hydroxy-2-heptylquinoline-N-oxide (HQNO). The employed synthetic MvfR antagonist fully inhibited pqs small molecule formation showing expected sigmoidal dose-response curves for 2-AA, HQNO, HHQ and PQS. Surprisingly, DHQ levels were enhanced at lower antagonist concentrations followed by a full suppression at higher QSI amounts. This particular bi-phasic profile hinted at the accumulation of a biosynthetic intermediate resulting in the observed overproduction of the shunt product DHQ. Additionally, investigations on PqsBC inhibitors showed a reduction of MvfR natural ligands, while increased 2-AA, DHQ and HQNO levels compared to the untreated cells were detected. Moreover, PqsBC inhibitors did not show any significant effect in PA14 pqsC mutant demonstrating their target selectivity. As 2-AA is important for antibacterial tolerance, the QSIs were evaluated in their capability to attenuate persistence. Indeed, persister cells were reduced along with 2-AA inhibition resulting from MvfR antagonism, but not from PqsBC inhibition. In conclusion, antagonizing MvfR using a dosage capable of fully suppressing this QS system will lead to a favorable therapeutic outcome as DHQ overproduction is avoided and bacterial persistence is reduced.
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Affiliation(s)
- Giuseppe Allegretta
- Department of Drug Design and Optimization, Helmholtz Institute for Pharmaceutical Research SaarlandSaarbrücken, Germany
| | - Christine K Maurer
- Department of Drug Design and Optimization, Helmholtz Institute for Pharmaceutical Research SaarlandSaarbrücken, Germany
| | - Jens Eberhard
- Department of Drug Design and Optimization, Helmholtz Institute for Pharmaceutical Research SaarlandSaarbrücken, Germany
| | - Damien Maura
- Department of Surgery and Department of Microbiology and Immunobiology, Harvard Medical School, BostonMA, United States.,Department of Surgery, Center for Surgery, Innovation and Bioengineering, Massachusetts General Hospital, BostonMA, United States.,Shriners Hospitals for Children, BostonMA, United States
| | - Rolf W Hartmann
- Department of Drug Design and Optimization, Helmholtz Institute for Pharmaceutical Research SaarlandSaarbrücken, Germany.,Pharmaceutical and Medicinal Chemistry, Saarland UniversitySaarbrücken, Germany
| | - Laurence Rahme
- Department of Surgery and Department of Microbiology and Immunobiology, Harvard Medical School, BostonMA, United States.,Department of Surgery, Center for Surgery, Innovation and Bioengineering, Massachusetts General Hospital, BostonMA, United States.,Shriners Hospitals for Children, BostonMA, United States
| | - Martin Empting
- Department of Drug Design and Optimization, Helmholtz Institute for Pharmaceutical Research SaarlandSaarbrücken, Germany
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49
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Concentrations systémiques d’antibiotiques potentiellement toxiques après administration par pansement imprégné chez un patient brûlé : à propos d’un cas clinique. Therapie 2016; 71:483-486. [DOI: 10.1016/j.therap.2016.03.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Accepted: 03/31/2016] [Indexed: 11/19/2022]
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50
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A Hydrogel‐Based Localized Release of Colistin for Antimicrobial Treatment of Burn Wound Infection. Macromol Biosci 2016; 17. [DOI: 10.1002/mabi.201600320] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Revised: 08/15/2016] [Indexed: 11/07/2022]
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