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Li JL, Li WL, Zhang J, Pang YT, Xiong J, Wu P, Wei BR, Li XJ, Huang Q, Tang QH, Zhao CH, Wang Q, Liu ZL, Chen Y, Dong ZX, Zhao YZ, Guo J. Seasonal dynamics of the microbiota and nutritional composition in bee bread from Apis cerana and Apis mellifera colonies. Food Res Int 2024; 190:113905. [PMID: 38945555 DOI: 10.1016/j.foodres.2023.113905] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2023] [Revised: 12/15/2023] [Accepted: 12/21/2023] [Indexed: 07/02/2024]
Abstract
Bee bread is a product of honeybees, which collect and ferment pollen, that contains highly nutritious and easily digestible active substances. However, its nutritional composition varies significantly with fermentation strains and seasonal changes. To unveil the patterns of microbial community and nutritional component changes in bee bread across seasons, we employed high-throughput techniques to assess the diversity of bacteria and fungi in bee bread. The results indicated that the compositions of bacteria and fungi in bee bread undergo significant seasonal variation, with noticeable changes in the microbial diversity of bee bread from different bee species. Subsequently, metabolomic analysis revealed high activity of glycerophospholipid metabolism in bee bread. Furthermore, our analysis identifaied noteworthy differences in nutritional components, including pH values, sugar content, and free amino acid levels, in bee bread across different seasons.
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Affiliation(s)
- Jia-Li Li
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, Yunnan 650500, China; Yunnan Zhongfeng Technology Development Co. LTD, Kunming, Yunnan 651701, China
| | - Wan-Li Li
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, Yunnan 650500, China
| | - Jun Zhang
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, Yunnan 650500, China
| | - Yan-Tao Pang
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, Yunnan 650500, China
| | - Jian Xiong
- Yunnan Zhongfeng Technology Development Co. LTD, Kunming, Yunnan 651701, China
| | - Ping Wu
- State Key Laboratory of Resource Insects, Institute of Apicultural Research, Chinese Academy of Agricultural Sciences, Beijing 100093, China
| | - Bang-Rong Wei
- State Key Laboratory of Resource Insects, Institute of Apicultural Research, Chinese Academy of Agricultural Sciences, Beijing 100093, China
| | - Xi-Jie Li
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, Yunnan 650500, China
| | - Qi Huang
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, Yunnan 650500, China
| | - Qi-He Tang
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, Yunnan 650500, China
| | - Chong-Hui Zhao
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, Yunnan 650500, China
| | - Qian Wang
- General Station of Bee Technology Promotion in Gansu Province/Gansu Provincial Bee Research Institute, China
| | - Zhan-Li Liu
- General Station of Bee Technology Promotion in Gansu Province/Gansu Provincial Bee Research Institute, China
| | - Yuan Chen
- Pujia Life Technology Development Co. LTD, Fuzhou 350018, China
| | - Zhi-Xiang Dong
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, Yunnan 650500, China.
| | - Ya-Zhou Zhao
- Nanchuan District Livestock, Veterinary and Fisheries Center, Chongqing 408400, China; State Key Laboratory of Resource Insects, Institute of Apicultural Research, Chinese Academy of Agricultural Sciences, Beijing 100093, China.
| | - Jun Guo
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, Yunnan 650500, China; Yunnan Zhongfeng Technology Development Co. LTD, Kunming, Yunnan 651701, China.
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2
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Saini M, Gaurav A, Hussain A, Pathania R. Small Molecule IITR08367 Potentiates Antibacterial Efficacy of Fosfomycin against Acinetobacter baumannii by Efflux Pump Inhibition. ACS Infect Dis 2024; 10:1711-1724. [PMID: 38562022 DOI: 10.1021/acsinfecdis.4c00077] [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] [Indexed: 04/04/2024]
Abstract
Fosfomycin is a broad-spectrum single-dose therapy approved for treating lower urinary tract infections. Acinetobacter baumannii, one of the five major UTI-causing pathogens, is intrinsically resistant to fosfomycin. Reduced uptake and active efflux are major reasons for this intrinsic resistance. AbaF, a major facilitator superfamily class of transporter in A. baumannii, is responsible for fosfomycin efflux and biofilm formation. This study describes the identification and validation of a novel small-molecule efflux pump inhibitor that potentiates fosfomycin efficacy against A. baumannii. An AbaF inhibitor screening was performed against Escherichia coli KAM32/pUC18_abaF, using the noninhibitory concentration of 24 putative efflux pump inhibitors. The inhibitory activity of IITR08367 [bis(4-methylbenzyl) disufide] against fosfomycin/H+ antiport was validated using ethidium bromide efflux, quinacrine-based proton-sensitive fluorescence, and membrane depolarization assays. IITR08367 inhibits fosfomycin/H+ antiport activity by perturbing the transmembrane proton gradient. IITR08367 is a nontoxic molecule that potentiates fosfomycin activity against clinical strains of A. baumannii and prevents biofilm formation by inhibiting efflux pump (AbaF). The IITR08367-fosfomycin combination reduced bacterial burden by > 3 log10 in kidney and bladder tissue in the murine UTI model. Overall, fosfomycin, in combination with IITR08367, holds the potential to treat urinary tract infections caused by A. baumannii.
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Affiliation(s)
- Mahak Saini
- Department of Biosciences and Bioengineering, Indian Institute of Technology, Roorkee, Uttarakhand 247 667, India
| | - Amit Gaurav
- Department of Biosciences and Bioengineering, Indian Institute of Technology, Roorkee, Uttarakhand 247 667, India
| | - Arsalan Hussain
- Department of Biosciences and Bioengineering, Indian Institute of Technology, Roorkee, Uttarakhand 247 667, India
| | - Ranjana Pathania
- Department of Biosciences and Bioengineering, Indian Institute of Technology, Roorkee, Uttarakhand 247 667, India
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Gautam D, Dolma KG, Khandelwal B, Gupta M, Singh M, Mahboob T, Teotia A, Thota P, Bhattacharya J, Goyal R, M.R. Oliveira S, Pereira MDL, Wiart C, Wilairatana P, Eawsakul K, Rahmatullah M, Saravanabhavan SS, Nissapatorn V. Green synthesis of silver nanoparticles using Ocimum sanctum Linn. and its antibacterial activity against multidrug resistant Acinetobacter baumannii. PeerJ 2023; 11:e15590. [PMID: 37529215 PMCID: PMC10389072 DOI: 10.7717/peerj.15590] [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: 09/07/2022] [Accepted: 05/29/2023] [Indexed: 08/03/2023] Open
Abstract
The biosynthesis of nanoparticles using the green route is an effective strategy in nanotechnology that provides a cost-effective and environmentally friendly alternative to physical and chemical methods. This study aims to prepare an aqueous extract of Ocimum sanctum (O. sanctum)-based silver nanoparticles (AgNPs) through the green route and test their antibacterial activity. The biosynthesized silver nanoparticles were characterised by colour change, UV spectrometric analysis, FTIR, and particle shape and size morphology by SEM and TEM images. The nanoparticles are almost spherical to oval or rod-shaped with smooth surfaces and have a mean particle size in the range of 55 nm with a zeta potential of -2.7 mV. The antibacterial activities of AgNPs evaluated against clinically isolated multidrug-resistant Acinetobacter baumannii (A. baumannii) showed that the AgNPs from O. sanctum are effective in inhibiting A. baumannii growth with a zone of inhibition of 15 mm in the agar well diffusion method and MIC and MBC of 32 µg/mL and 64 µg/mL, respectively. The SEM images of A. baumannii treated with AgNPs revealed damage and rupture in bacterial cells. The time-killing assay by spectrophotometry revealed the time- and dose-dependent killing action of AgNPs against A. baumannii, and the assay at various concentrations and time intervals indicated a statistically significant result in comparison with the positive control colistin at 2 µg/mL (P < 0.05). The cytotoxicity test using the MTT assay protocol showed that prepared nanoparticles of O. sanctum are less toxic against human cell A549. This study opens up a ray of hope to explore the further research in this area and to improve the antimicrobial activities against multidrug resistant bacteria.
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Affiliation(s)
- Deepan Gautam
- School of Allied Health Sciences and World Union for Herbal Drug Discovery (WUHeDD), Walailak University, Nakhon Si Thammarat, Thailand
- Department of Microbiology, Sikkim Manipal Institute of Medical Sciences, Sikkim Manipal University, Gangtok, Sikkim, India
| | - Karma Gurmey Dolma
- Department of Microbiology, Sikkim Manipal Institute of Medical Sciences, Sikkim Manipal University, Gangtok, Sikkim, India
| | - Bidita Khandelwal
- Department of Medicine, Sikkim Manipal Institute of Medical Sciences, Sikkim Manipal University, Gangtok, Sikkim, India
| | - Madhu Gupta
- Department of Pharmaceutics, School of Pharmaceutical Sciences, Delhi Pharmaceutical Sciences and Research University, New Delhi, India
| | - Meghna Singh
- Department of Pharmaceutics, School of Pharmaceutical Sciences, Delhi Pharmaceutical Sciences and Research University, New Delhi, India
| | - Tooba Mahboob
- School of Allied Health Sciences and World Union for Herbal Drug Discovery (WUHeDD), Walailak University, Nakhon Si Thammarat, Thailand
| | - Anil Teotia
- Department of Microbiology, Indian Pharmacopoeia Commission, Ministry of Health and Family Welfare, Ghaziabad, Utter Pradesh, India
| | - Prasad Thota
- Department of Microbiology, Indian Pharmacopoeia Commission, Ministry of Health and Family Welfare, Ghaziabad, Utter Pradesh, India
| | | | - Ramesh Goyal
- Department of Pharmacology, Delhi Pharmaceutical Sciences and Research University, New Delhi, India
| | - Sonia M.R. Oliveira
- Hunter Medical Research Institute, New Lambton, Australia
- CICECO-Aveiro Institute of Materials, University of Aveiro, Aveiro, Portugal
| | - Maria de Lourdes Pereira
- CICECO-Aveiro Institute of Materials, University of Aveiro, Aveiro, Portugal
- Department of Medical Science, University of Aveiro, Aveiro, Portugal
| | - Christophe Wiart
- The Institute for Tropical Biology and Conservation, University Malaysia Sabah, Sabah, Malaysia
| | - Polrat Wilairatana
- Department of Clinical Tropical Medicine, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Komgrit Eawsakul
- School of Medicine, Walailak University, Nakhon Si Thammarat, Thailand
| | - Mohammed Rahmatullah
- Department of Biotechnology & Genetic Engineering, University of Development Alternative, Dhaka, Bangladesh
| | - Shanmuga Sundar Saravanabhavan
- Department of Biotechnology, Aarupadai Veedu Institute of Technology, Vinayak Mission’s Research Foundation (DU), Chennai, Tamil Nadu, India
| | - Veeranoot Nissapatorn
- School of Allied Health Sciences and World Union for Herbal Drug Discovery (WUHeDD), Walailak University, Nakhon Si Thammarat, Thailand
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Rajaramon S, Shanmugam K, Dandela R, Solomon AP. Emerging evidence-based innovative approaches to control catheter-associated urinary tract infection: a review. Front Cell Infect Microbiol 2023; 13:1134433. [PMID: 37560318 PMCID: PMC10407108 DOI: 10.3389/fcimb.2023.1134433] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Accepted: 07/04/2023] [Indexed: 08/11/2023] Open
Abstract
Healthcare settings have dramatically advanced the latest medical devices, such as urinary catheters (UC) for infection, prevention, and control (IPC). The continuous or intermittent flow of a warm and conducive (urine) medium in the medical device, the urinary catheter, promotes the formation of biofilms and encrustations, thereby leading to the incidence of CAUTI. Additionally, the absence of an innate immune host response in and around the lumen of the catheter reduces microbial phagocytosis and drug action. Hence, the review comprehensively overviews the challenges posed by CAUTI and associated risks in patients' morbidity and mortality. Also, detailed, up-to-date information on the various strategies that blended/tailored the surface properties of UC to have anti-fouling, biocidal, and anti-adhesive properties to provide an outlook on how they can be better managed with futuristic solutions.
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Affiliation(s)
- Shobana Rajaramon
- Quorum Sensing Laboratory, Centre for Research in Infectious Diseases (CRID), School of Chemical and Biotechnology, SASTRA Deemed to be University, Thanjavur, India
| | - Karthi Shanmugam
- Quorum Sensing Laboratory, Centre for Research in Infectious Diseases (CRID), School of Chemical and Biotechnology, SASTRA Deemed to be University, Thanjavur, India
| | - Rambabu Dandela
- Department of Industrial and Engineering Chemistry, Institute of Chemical Technology, Bhubaneswar, Odisha, India
| | - Adline Princy Solomon
- Quorum Sensing Laboratory, Centre for Research in Infectious Diseases (CRID), School of Chemical and Biotechnology, SASTRA Deemed to be University, Thanjavur, India
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Misra T, Tare M, Jha PN. Characterization of functional amyloid curli in biofilm formation of an environmental isolate Enterobacter cloacae SBP-8. Antonie Van Leeuwenhoek 2023:10.1007/s10482-023-01843-y. [PMID: 37243862 DOI: 10.1007/s10482-023-01843-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 05/12/2023] [Indexed: 05/29/2023]
Abstract
The biofilm formation by bacteria is a complex process that is strongly mediated by various genetic and environmental factors. Biofilms contribute to disease infestation, especially in chronic infections. It is, therefore important to understand the factors affecting biofilm formation. This study reports the role of a functional amyloid curli in biofilm formation at various abiotic surfaces, including medical devices, by an environmental isolate of Enterobacter cloacae (SBP-8) which has been known for its pathogenic potential. A knockout mutant of csgA, the gene encoding the major structural unit of curli, was created to study the effect of curli on biofilm formation by E. cloacae SBP-8. Our findings confirm the production of curli at 25 °C and 37 °C in the wild-type strain. We further investigated the role of curli in the attachment of E. cloacae SBP-8 to glass, enteral feeding tube, and foley latex catheter. Contrary to the previous studies reporting the curli production below 30 °C in the majority of biofilm-forming bacterial species, we observed its production in E. cloacae SBP-8 at 37 °C. The formation of more intense biofilm in wild-type strain on various surfaces compared to curli-deficient strain (ΔcsgA) at both 25 °C and 37 °C suggested a prominent role of curli in biofilm formation. Further, electron and confocal microscopy studies demonstrated the formation of diffused monolayers of microbial cells on the abiotic surfaces by ΔcsgA strain as compared to the thick biofilm by respective wild-type strain, indicating the involvement of curli in biofilm formation by E. cloacae SBP-8. Overall, our findings provide insight into biofilm formation mediated by curli in E. cloacae SBP-8. Further, we show that it can be expressed at a physiological temperature on all surfaces, thereby indicating the potential role of curli in pathogenesis.
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Affiliation(s)
- Tripti Misra
- Department of Biological Sciences, Birla Institute of Technology and Science, Pilani, Rajasthan, 333031, India
| | - Meghana Tare
- Department of Biological Sciences, Birla Institute of Technology and Science, Pilani, Rajasthan, 333031, India.
| | - Prabhat Nath Jha
- Department of Biological Sciences, Birla Institute of Technology and Science, Pilani, Rajasthan, 333031, India.
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Barajas-García CC, Guerrero-Barrera AL, Arreola-Guerra JM, Avelar-González FJ, Ramírez-Castillo FY. Detection of microbial biofilms inside the lumen of ureteral stents: two case reports. J Med Case Rep 2023; 17:174. [PMID: 37069667 PMCID: PMC10111790 DOI: 10.1186/s13256-023-03849-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Accepted: 02/06/2023] [Indexed: 04/19/2023] Open
Abstract
BACKGROUND We report large biofilm structures that covered almost the entirety of the lumen and surface of double-J stents in two postrenal transplant patients, with no development of urinary tract infection. Biofilm bacteria of one patient were integrated by coccus in a net structure, whereas overlapping cells of bacilli were present in the other patient. To the best of our knowledge, this is the first time that high-quality images of the architecture of noncrystalline biofilms have been found inside double-J stents from long-term stenting in renal transplant recipients. CASE PRESENTATION Two renal transplant recipients, a 34-year-old male and a 39-year-old female of Mexican-Mestizo origin, who underwent a first renal transplant and lost it due to allograft failure, had a second transplant. Two months after the surgical procedure, double-J stents were removed and analyzed using scanning electron microscopy (SEM). None of the patients had an antecedent of UTI, and none developed UTI after urinary device removal. There were no reports of injuries, encrustation, or discomfort caused by these devices. CONCLUSION The bacterial biofilm inside the J stent from long-term stenting in renal transplant recipients was mainly concentrated on unique bacteria. Biofilm structures from the outside and inside of stents do not have crystalline phases. Internal biofilms may represent a high number of bacteria in the double-J stent, in the absence of crystals.
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Affiliation(s)
- Carolina C Barajas-García
- Laboratorio de Biología Celular y Tisular, Departamento de Morfología, Universidad Autónoma de Aguascalientes, Aguascalientes, Mexico
| | - Alma L Guerrero-Barrera
- Laboratorio de Biología Celular y Tisular, Departamento de Morfología, Universidad Autónoma de Aguascalientes, Aguascalientes, Mexico.
| | - José M Arreola-Guerra
- Departamento de Nefrología, Hospital Centenario Miguel Hidalgo, Aguascalientes, Mexico
| | | | - Flor Y Ramírez-Castillo
- Laboratorio de Biología Celular y Tisular, Departamento de Morfología, Universidad Autónoma de Aguascalientes, Aguascalientes, Mexico
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Amante C, De Soricellis C, Luccheo G, Luccheo L, Russo P, Aquino RP, Del Gaudio P. Flogomicina: A Natural Antioxidant Mixture as an Alternative Strategy to Reduce Biofilm Formation. Life (Basel) 2023; 13:life13041005. [PMID: 37109533 PMCID: PMC10142241 DOI: 10.3390/life13041005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 04/07/2023] [Accepted: 04/12/2023] [Indexed: 04/29/2023] Open
Abstract
The National Institute of Health has reported that approximately 80% of chronic infections are associated with biofilms, which are indicated as one of the main reasons for bacteria's resistance to antimicrobial agents. Several studies have revealed the role of N-acetylcysteine (NAC), in reducing biofilm formation induced by different microorganisms. A novel mixture made up of NAC and different natural ingredients (bromelain, ascorbic acid, Ribes nigrum, resveratrol, and pelargonium) has been developed in order to obtain a pool of antioxidants as an alternative strategy for biofilm reduction. The study has demonstrated that the mixture is able to significantly enhance NAC activity against different Gram-positive and Gram-negative bacteria. It has shown an increase in NAC permeation in vitro through an artificial fluid, moving from 2.5 to 8 μg/cm2 after 30 min and from 4.4 to 21.6 μg/cm2 after 180 min, and exhibiting a strongly fibrinolytic activity compared to the single components of the mixture. Moreover, this novel mixture has exhibited an antibiofilm activity against S aureus and the ability to reduce S. aureus growth by more than 20% in a time-killing assay, while on E. coli, and P. mirabilis, the growth was reduced by more than 80% compared to NAC. The flogomicina mixture has also been proven capable of reducing bacterial adhesion to abiotic surfaces of E.coli, by more than 11% concerning only the NAC. In combination with amoxicillin, it has been shown to significantly increase the drug's effectiveness after 14 days, offering a safe and natural way to reduce the daily dosage of antibiotics in prolonged therapies and consequently, reduce antibiotic resistance.
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Affiliation(s)
- Chiara Amante
- Department of Pharmacy, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano, SA, Italy
| | - Chiara De Soricellis
- Department of Pharmacy, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano, SA, Italy
| | - Gianni Luccheo
- Anvest Health s.r.l., Via Rosario Livatino, 84083 Castel San Giorgio, SA, Italy
| | - Luigi Luccheo
- Anvest Health s.r.l., Via Rosario Livatino, 84083 Castel San Giorgio, SA, Italy
| | - Paola Russo
- Department of Pharmacy, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano, SA, Italy
| | - Rita Patrizia Aquino
- Department of Pharmacy, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano, SA, Italy
| | - Pasquale Del Gaudio
- Department of Pharmacy, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano, SA, Italy
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Crintea A, Carpa R, Mitre AO, Petho RI, Chelaru VF, Nădășan SM, Neamti L, Dutu AG. Nanotechnology Involved in Treating Urinary Tract Infections: An Overview. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:555. [PMID: 36770516 PMCID: PMC9919202 DOI: 10.3390/nano13030555] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 01/22/2023] [Accepted: 01/27/2023] [Indexed: 06/18/2023]
Abstract
Considered as the most frequent contaminations that do not require hospitalization, urinary tract infections (UTIs) are largely known to cause significant personal burdens on patients. Although UTIs overall are highly preventable health issues, the recourse to antibiotics as drug treatments for these infections is a worryingly spread approach that should be addressed and gradually overcome in a contemporary, modernized healthcare system. With a virtually alarming global rise of antibiotic resistance overall, nanotechnologies may prove to be the much-needed 'lifebuoy' that will eventually suppress this prejudicial phenomenon. This review aims to present the most promising, currently known nano-solutions, with glimpses on clinical and epidemiological aspects of the UTIs, prospective diagnostic instruments, and non-antibiotic treatments, all of these engulfed in a comprehensive overview.
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Affiliation(s)
- Andreea Crintea
- Department of Medical Biochemistry, Faculty of Medicine, Iuliu Hatieganu University of Medicine and Pharmacy, 400349 Cluj-Napoca, Romania
| | - Rahela Carpa
- Department of Molecular Biology and Biotechnology, Faculty of Biology and Geology, Babes-Bolyai University, 400084 Cluj-Napoca, Romania
| | - Andrei-Otto Mitre
- Department of Pathophysiology, Faculty of Medicine, Iuliu Hatieganu University of Medicine and Pharmacy, 400349 Cluj-Napoca, Romania
| | - Robert Istvan Petho
- Faculty of Medicine, Iuliu Hatieganu University of Medicine and Pharmacy, 400349 Cluj-Napoca, Romania
| | - Vlad-Florin Chelaru
- Faculty of Medicine, Iuliu Hatieganu University of Medicine and Pharmacy, 400349 Cluj-Napoca, Romania
| | - Sebastian-Mihail Nădășan
- Faculty of Medicine, Iuliu Hatieganu University of Medicine and Pharmacy, 400349 Cluj-Napoca, Romania
| | - Lidia Neamti
- Department of Medical Biochemistry, Faculty of Medicine, Iuliu Hatieganu University of Medicine and Pharmacy, 400349 Cluj-Napoca, Romania
| | - Alina Gabriela Dutu
- Department of Medical Biochemistry, Faculty of Medicine, Iuliu Hatieganu University of Medicine and Pharmacy, 400349 Cluj-Napoca, Romania
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Graham GD, Jeray KJ. Posttraumatic Patellar Osteomyelitis due to Raoultella ornithinolytica: A Case Report. JBJS Case Connect 2023; 13:01709767-202303000-00039. [PMID: 36795860 DOI: 10.2106/jbjs.cc.22.00590] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
CASE A 59-year-old woman sustained a comminuted patellar fracture after a fall from standing. The injury was treated with open reduction and internal fixation 7 days from initial injury. Seven weeks postoperatively, she developed a swollen, painful, and draining knee. Workup demonstrated Raoultella ornithinolytica. She underwent surgical debridement and antibiotic treatment. CONCLUSION This is an unusual presentation of patellar osteomyelitis with R. ornithinolytica. Early identification, treatment with appropriate antimicrobial therapy, and consideration of surgical debridement are important in patients presenting with pain, swelling, and erythema after surgery.
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Affiliation(s)
- George D Graham
- Department of Orthopaedic Surgery, Prisma Health - Upstate, Greenville, South Carolina
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10
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Misra T, Tare M, Jha PN. Insights Into the Dynamics and Composition of Biofilm Formed by Environmental Isolate of Enterobacter cloacae. Front Microbiol 2022; 13:877060. [PMID: 35865928 PMCID: PMC9294512 DOI: 10.3389/fmicb.2022.877060] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 05/27/2022] [Indexed: 11/13/2022] Open
Abstract
Bacterial biofilms are clinically admissible and illustrate an influential role in infections, particularly those related to the implant of medical devices. The characterization of biofilms is important to understand the etiology of the diseases. Enterobacter cloacae are known for causing infections by forming biofilms on various abiotic surfaces, such as medical devices. However, a detailed characterization in terms of morphology and the molecular composition of the formed biofilms by this bacterium is sparse. The present study provides insights into the biofilm formation of E. cloacae SBP-8, an environmental isolate, on various surfaces. We performed assays to understand the biofilm-forming capability of the SBP-8 strain and characterized the adhering potential of the bacteria on the surface of different medical devices (foley latex catheter, enteral feeding tube, and glass) at different temperatures. We found that medical devices exhibited strong colonization by E. cloacae SBP-8. Using field emission-scanning electron microscopy (FE-SEM) studies, we characterized the biofilms as a function of time. It indicated stronger biofilm formation in terms of cellular density and EPS production on the surfaces. Further, we characterized the biofilm employing surface-enhanced Raman spectroscopy (SERS) and identified the vast heterogenic nature of the biofilm-forming molecules. Interestingly, we also found that this heterogeneity varies from the initial stages of biofilm formation until the maturation and dispersion. Our studies provide insights into biofilm composition over a period of time, which might aid in understanding the biofilm dispersion phases, to enhance the presently available treatment strategies.
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Affiliation(s)
| | - Meghana Tare
- Department of Biological Sciences, Birla Institute of Technology and Science, Pilani, India
| | - Prabhat Nath Jha
- Department of Biological Sciences, Birla Institute of Technology and Science, Pilani, India
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11
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Roy S, Chowdhury G, Mukhopadhyay AK, Dutta S, Basu S. Convergence of Biofilm Formation and Antibiotic Resistance in Acinetobacter baumannii Infection. Front Med (Lausanne) 2022; 9:793615. [PMID: 35402433 PMCID: PMC8987773 DOI: 10.3389/fmed.2022.793615] [Citation(s) in RCA: 47] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Accepted: 01/31/2022] [Indexed: 07/30/2023] Open
Abstract
Acinetobacter baumannii (A. baumannii) is a leading cause of nosocomial infections as this pathogen has certain attributes that facilitate the subversion of natural defenses of the human body. A. baumannii acquires antibiotic resistance determinants easily and can thrive on both biotic and abiotic surfaces. Different resistance mechanisms or determinants, both transmissible and non-transmissible, have aided in this victory over antibiotics. In addition, the propensity to form biofilms (communities of organism attached to a surface) allows the organism to persist in hospitals on various medical surfaces (cardiac valves, artificial joints, catheters, endotracheal tubes, and ventilators) and also evade antibiotics simply by shielding the bacteria and increasing its ability to acquire foreign genetic material through lateral gene transfer. The biofilm formation rate in A. baumannii is higher than in other species. Recent research has shown how A. baumannii biofilm-forming capacity exerts its effect on resistance phenotypes, development of resistome, and dissemination of resistance genes within biofilms by conjugation or transformation, thereby making biofilm a hotspot for genetic exchange. Various genes control the formation of A. baumannii biofilms and a beneficial relationship between biofilm formation and "antimicrobial resistance" (AMR) exists in the organism. This review discusses these various attributes of the organism that act independently or synergistically to cause hospital infections. Evolution of AMR in A. baumannii, resistance mechanisms including both transmissible (hydrolyzing enzymes) and non-transmissible (efflux pumps and chromosomal mutations) are presented. Intrinsic factors [biofilm-associated protein, outer membrane protein A, chaperon-usher pilus, iron uptake mechanism, poly-β-(1, 6)-N-acetyl glucosamine, BfmS/BfmR two-component system, PER-1, quorum sensing] involved in biofilm production, extrinsic factors (surface property, growth temperature, growth medium) associated with the process, the impact of biofilms on high antimicrobial tolerance and regulation of the process, gene transfer within the biofilm, are elaborated. The infections associated with colonization of A. baumannii on medical devices are discussed. Each important device-related infection is dealt with and both adult and pediatric studies are separately mentioned. Furthermore, the strategies of preventing A. baumannii biofilms with antibiotic combinations, quorum sensing quenchers, natural products, efflux pump inhibitors, antimicrobial peptides, nanoparticles, and phage therapy are enumerated.
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Affiliation(s)
- Subhasree Roy
- Division of Bacteriology, Indian Council of Medical Research (ICMR)-National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Goutam Chowdhury
- Division of Molecular Microbiology, Indian Council of Medical Research (ICMR)-National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Asish K. Mukhopadhyay
- Division of Molecular Microbiology, Indian Council of Medical Research (ICMR)-National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Shanta Dutta
- Division of Bacteriology, Indian Council of Medical Research (ICMR)-National Institute of Cholera and Enteric Diseases, Kolkata, India
| | - Sulagna Basu
- Division of Bacteriology, Indian Council of Medical Research (ICMR)-National Institute of Cholera and Enteric Diseases, Kolkata, India
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Kasza K, Gurnani P, Hardie KR, Cámara M, Alexander C. Challenges and solutions in polymer drug delivery for bacterial biofilm treatment: A tissue-by-tissue account. Adv Drug Deliv Rev 2021; 178:113973. [PMID: 34530014 DOI: 10.1016/j.addr.2021.113973] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Revised: 08/12/2021] [Accepted: 09/08/2021] [Indexed: 02/07/2023]
Abstract
To tackle the emerging antibiotic resistance crisis, novel antimicrobial approaches are urgently needed. Bacterial communities (biofilms) are a particular concern in this context. Biofilms are responsible for most human infections and are inherently less susceptible to antibiotic treatments. Biofilms have been linked with several challenging chronic diseases, including implant-associated osteomyelitis and chronic wounds. The specific local environments present in the infected tissues further contribute to the rise in antibiotic resistance by limiting the efficacy of systemic antibiotic therapies and reducing drug concentrations at the infection site, which can lead to reoccurring infections. To overcome the shortcomings of systemic drug delivery, encapsulation within polymeric carriers has been shown to enhance antimicrobial efficacy, permeation and retention at the infection site. In this Review, we present an overview of current strategies for antimicrobial encapsulation within polymeric carriers, comparing challenges and solutions on a tissue-by-tissue basis. We compare challenges and proposed drug delivery solutions from the perspective of the local environments for biofilms found in oral, wound, gastric, urinary tract, bone, pulmonary, vaginal, ocular and middle/inner ear tissues. We will also discuss future challenges and barriers to clinical translation for these therapeutics. The following Review demonstrates there is a significant imbalance between the research focus being placed on different tissue types, with some targets (oral and wound biofims) being extensively more studied than others (vaginal and otitis media biofilms and endocarditis). Furthermore, the importance of the local tissue environment when selecting target therapies is demonstrated, with some materials being optimal choices for certain sites of bacterial infection, while having limited applicability in others.
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Rahuman HBH, Dhandapani R, Palanivel V, Thangavelu S, Paramasivam R, Muthupandian S. Bioengineered phytomolecules-capped silver nanoparticles using Carissa carandas leaf extract to embed on to urinary catheter to combat UTI pathogens. PLoS One 2021; 16:e0256748. [PMID: 34473763 PMCID: PMC8412375 DOI: 10.1371/journal.pone.0256748] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Accepted: 08/14/2021] [Indexed: 12/04/2022] Open
Abstract
Rising incidents of urinary tract infections (UTIs) among catheterized patients is a noteworthy problem in clinic due to their colonization of uropathogens on abiotic surfaces. Herein, we have examined the surface modification of urinary catheter by embedding with eco-friendly synthesized phytomolecules-capped silver nanoparticles (AgNPs) to prevent the invasion and colonization of uropathogens. The preliminary confirmation of AgNPs production in the reaction mixture was witnessed by the colour change and surface resonance plasmon (SRP) band at 410nm by UV–visible spectroscopy. The morphology, size, crystalline nature, and elemental composition of attained AgNPs were further confirmed by the transmission electron microscopy (TEM), selected area electron diffraction (SAED), X-ray diffraction (XRD) technique, Scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The functional groups of AgNPs with stabilization/capped phytochemicals were detected by Fourier-transform infrared spectroscopy (FTIR). Further, antibiofilm activity of synthesized AgNPs against biofilm producers such as Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa were determined by viability assays and micrographically. AgNPs coated and coating-free catheters performed to treat with bacterial pathogen to analyze the mat formation and disruption of biofilm formation. Synergistic effect of AgNPs with antibiotic reveals that it can enhance the activity of antibiotics, AgNPs coated catheter revealed that, it has potential antimicrobial activity and antibiofilm activity. In summary, C. carandas leaf extract mediated synthesized AgNPs will open a new avenue and a promising template to embed on urinary catheter to control clinical pathogens.
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Affiliation(s)
| | - Ranjithkumar Dhandapani
- Department of Microbiology, Science Campus, Alagappa University, Karaikudi, Tamilnadu, India
| | - Velmurugan Palanivel
- Centre for for Material Engineering and Regenerative Medicine Bharath Institute of Higher Education, Chennai, India
- * E-mail: (SM); (VP)
| | | | - Ragul Paramasivam
- Chimertech Innovations LLP, Tamilnadu Veterinary and Animal Science University, Chennai, India
| | - Saravanan Muthupandian
- Division of Biomedical sciences, College of Health Sciences, School of Medicine, Mekelle, Ethiopia
- AMR and Nanomedicine Laboratory, Department of Pharmacology, Saveetha Dental College, Saveetha Institute of Medical and Technical Sciences (SIMATS), Chennai, India
- * E-mail: (SM); (VP)
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Pompilio A, Scribano D, Sarshar M, Di Bonaventura G, Palamara AT, Ambrosi C. Gram-Negative Bacteria Holding Together in a Biofilm: The Acinetobacter baumannii Way. Microorganisms 2021; 9:1353. [PMID: 34206680 PMCID: PMC8304980 DOI: 10.3390/microorganisms9071353] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 06/14/2021] [Accepted: 06/18/2021] [Indexed: 12/24/2022] Open
Abstract
Bacterial biofilms are a serious public-health problem worldwide. In recent years, the rates of antibiotic-resistant Gram-negative bacteria associated with biofilm-forming activity have increased worrisomely, particularly among healthcare-associated pathogens. Acinetobacter baumannii is a critically opportunistic pathogen, due to the high rates of antibiotic resistant strains causing healthcare-acquired infections (HAIs). The clinical isolates of A. baumannii can form biofilms on both biotic and abiotic surfaces; hospital settings and medical devices are the ideal environments for A. baumannii biofilms, thereby representing the main source of patient infections. However, the paucity of therapeutic options poses major concerns for human health infections caused by A. baumannii strains. The increasing number of multidrug-resistant A. baumannii biofilm-forming isolates in association with the limited number of biofilm-eradicating treatments intensify the need for effective antibiofilm approaches. This review discusses the mechanisms used by this opportunistic pathogen to form biofilms, describes their clinical impact, and summarizes the current and emerging treatment options available, both to prevent their formation and to disrupt preformed A. baumannii biofilms.
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Affiliation(s)
- Arianna Pompilio
- Center for Advanced Studies and Technology (CAST), Department of Medical, Oral and Biotechnological Sciences, Service of Clinical Microbiology, “G. d’Annunzio” University of Chieti-Pescara, 66100 Chieti, Italy; (A.P.); (G.D.B.)
| | - Daniela Scribano
- Department of Public Health and Infectious Diseases, Sapienza University of Rome, 00185 Rome, Italy;
- Dani Di Giò Foundation-Onlus, 00193 Rome, Italy
| | - Meysam Sarshar
- Research Laboratories, Bambino Gesù Children’s Hospital, IRCCS, 00146 Rome, Italy;
| | - Giovanni Di Bonaventura
- Center for Advanced Studies and Technology (CAST), Department of Medical, Oral and Biotechnological Sciences, Service of Clinical Microbiology, “G. d’Annunzio” University of Chieti-Pescara, 66100 Chieti, Italy; (A.P.); (G.D.B.)
| | - Anna Teresa Palamara
- Department of Infectious Diseases, Istituto Superiore di Sanità, 00161 Rome, Italy;
- Laboratory Affiliated to Institute Pasteur Italia-Cenci Bolognetti Foundation, Department of Public Health and Infectious Diseases, Sapienza University of Rome, 00185 Rome, Italy
| | - Cecilia Ambrosi
- Department of Human Sciences and Promotion of the Quality of Life, San Raffaele Open University, IRCCS, 00166 Rome, Italy
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Biofilm Development on Urinary Catheters Promotes the Appearance of Viable but Nonculturable Bacteria. mBio 2021; 12:mBio.03584-20. [PMID: 33758085 PMCID: PMC8092313 DOI: 10.1128/mbio.03584-20] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Several antimicrobial urinary catheter materials have been developed, but, although laboratory studies may show a benefit, none have significantly improved clinical outcomes. The use of poorly designed laboratory testing and lack of consideration of the impact of VBNC populations may be responsible. Catheter-associated urinary tract infections have serious consequences, for both patients and health care resources. Much work has been carried out to develop an antimicrobial catheter. Although such developments have shown promise under laboratory conditions, none have demonstrated a clear advantage in clinical trials. Using a range of microbiological and advanced microscopy techniques, a detailed laboratory study comparing biofilm development on silicone, hydrogel latex, and silver alloy-coated hydrogel latex catheters was carried out. Biofilm development by Escherichia coli, Pseudomonas aeruginosa, and Proteus mirabilis on three commercially available catheters was tracked over time. Samples were examined with episcopic differential interference contrast (EDIC) microscopy, culture analysis, and staining techniques to quantify viable but nonculturable (VBNC) bacteria. Both qualitative and quantitative assessments found biofilms to develop rapidly on all three materials. EDIC microscopy revealed the rough surface topography of the materials. Differences between culture counts and quantification of total and dead cells demonstrated the presence of VBNC populations, where bacteria retain viability but are not metabolically active. The use of nonculture-based techniques showed the development of widespread VBNC populations. These VBNC populations were more evident on silver alloy-coated hydrogel latex catheters, indicating a bacteriostatic effect at best. The laboratory tests reported here, which detect VBNC bacteria, allow more rigorous assessment of antimicrobial catheters, explaining why there is often minimal benefit to patients.
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Bagińska N, Cieślik M, Górski A, Jończyk-Matysiak E. The Role of Antibiotic Resistant A. baumannii in the Pathogenesis of Urinary Tract Infection and the Potential of Its Treatment with the Use of Bacteriophage Therapy. Antibiotics (Basel) 2021; 10:281. [PMID: 33803438 PMCID: PMC8001842 DOI: 10.3390/antibiotics10030281] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 03/01/2021] [Accepted: 03/05/2021] [Indexed: 12/20/2022] Open
Abstract
Acinetobacter baumannii are bacteria that belong to the critical priority group due to their carbapenems and third generation cephalosporins resistance, which are last-chance antibiotics. The growing multi-drug resistance and the ability of these bacteria to form biofilms makes it difficult to treat infections caused by this species, which often affects people with immunodeficiency or intensive care unit patients. In addition, most of the infections are associated with catheterization of patients. These bacteria are causative agents, inter alia, of urinary tract infections (UTI) which can cause serious medical and social problems, because of treatment difficulties as well as the possibility of recurrence and thus severely decrease patients' quality of life. Therefore, a promising alternative to standard antibiotic therapy can be bacteriophage therapy, which will generate lower costs and will be safer for the treated patients and has real potential to be much more effective. The aim of the review is to outline the important role of drug-resistant A. baumannii in the pathogenesis of UTI and highlight the potential for fighting these infections with bacteriophage therapy. Further studies on the use of bacteriophages in the treatment of UTIs in animal models may lead to the use of bacteriophage therapy in human urinary tract infections caused by A. baumannii in the future.
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Affiliation(s)
- Natalia Bagińska
- Bacteriophage Laboratory, Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, 53-114 Wrocław, Poland; (N.B.); (M.C.); (A.G.)
| | - Martyna Cieślik
- Bacteriophage Laboratory, Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, 53-114 Wrocław, Poland; (N.B.); (M.C.); (A.G.)
| | - Andrzej Górski
- Bacteriophage Laboratory, Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, 53-114 Wrocław, Poland; (N.B.); (M.C.); (A.G.)
- Phage Therapy Unit, Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, 53-114 Wrocław, Poland
- Infant Jesus Hospital, The Medical University of Warsaw, 02-006 Warsaw, Poland
| | - Ewa Jończyk-Matysiak
- Bacteriophage Laboratory, Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, 53-114 Wrocław, Poland; (N.B.); (M.C.); (A.G.)
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Indwelling Device-Associated Biofilms in Critically Ill Cancer Patients-Study Protocol. Pathogens 2021; 10:pathogens10030306. [PMID: 33800769 PMCID: PMC8001301 DOI: 10.3390/pathogens10030306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Revised: 02/28/2021] [Accepted: 03/03/2021] [Indexed: 11/26/2022] Open
Abstract
Health care-associated infections are a leading cause of inpatient complications. Rapid pathogen detection/identification is a major challenge in sepsis management that highly influences the successful outcome. The current standard of microorganism identification relies on bacterial growth in culture, which has several limitations. Gene sequencing research has developed culture-independent techniques for microorganism identification, with the aim to improve etiological diagnosis and, therefore, to change sepsis outcome. A prospective, observational, non-interventional, single-center study was designed that assesses biofilm-associated pathogens in a specific subpopulation of septic critically ill cancer patients. Indwelling device samples will be collected in septic patients at the moment of the removal of the arterial catheter, central venous catheter, endotracheal tube and urinary catheter. Concomitantly, clinical data regarding 4 sites (nasal, pharyngeal, rectal and skin) of pathogen colonization at the time of hospital/intensive care admission will be collected. The present study aims to offer new insights into biofilm-associated infections and to evaluate the infection caused by catheter-specific and patient-specific biofilm-associated pathogens in association with the extent of colonization. The analysis relies on the two following detection/identification techniques: standard microbiological method and next generation sequencing (NGS). Retrospectively, the study will estimate the clinical value of the NGS-based detection and its virtual potential in changing patient management and outcome, notably in the subjects with missing sepsis source or lack of response to anti-infective treatment.
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Biofilm-Producing Bacteria and Risk Factors (Gender and Duration of Catheterization) Characterized as Catheter-Associated Biofilm Formation. Int J Microbiol 2021; 2021:8869275. [PMID: 33688348 PMCID: PMC7920707 DOI: 10.1155/2021/8869275] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 01/31/2021] [Accepted: 02/08/2021] [Indexed: 12/19/2022] Open
Abstract
Background A catheter-associated urinary tract infection (CA-UTI) is preceded by biofilm formation, which is related to several risk factors such as gender, age, diabetic status, duration of catheterization, bacteriuria before catheterization, virulence gene factor, and antibiotic usage. Aims This study aims to identify the microbial composition of catheter samples, including its corresponding comparison with urine samples, to determine the most important risk factors of biofilm formation and characterize the virulence gene factors that correlate with biofilm formation. Methods A longitudinal cross-sectional study was conducted on 109 catheterized patients from September 2017 to January 2018. The risk factors were obtained from the patients' medical records. All catheter and urine samples were cultured after removal, followed by biomass quantification. Isolate identification and antimicrobial susceptibility testing were performed using the Vitex2 system. Biofilm-producing bacteria were identified by the Congo Red Agar (CRA) method. A PCR test characterized the virulence genes of dominant bacteria (E. coli). All data were collected and processed for statistical analysis. Results Out of 109 catheterized patients, 78% of the catheters were culture positive, which was higher than those of the urine samples (37.62%). The most common species isolated from the catheter cultures were Escherichia coli (28.1%), Candida sp. (17.8%), Klebsiella pneumoniae (15.9%), and Enterococcus faecalis (13.1%). E. coli (83.3%) and E. faecalis (78.6%) were the main isolates with a positive CRA. A statistical analysis showed that gender and duration prior to catheterization were associated with an increased risk of biofilm formation (p < 0.05). Conclusion E. coli and E. faecalis were the most common biofilm-producing bacteria isolated from the urinary catheter. Gender and duration are two risk factors associated with biofilm formation, therefore determining the risk of CAUTI. The presence of PapC as a virulence gene encoding pili correlates with the biofilm formation. Biofilm-producing bacteria, female gender, duration of catheterization (more than five days), and PapC gene presence have strong correlation with the biofilm formation. To prevent CAUTI, patients with risk factors should be monitored by urinalysis tests to detect earlier the risk of biofilm formation.
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Koc H, Kilicay E, Karahaliloglu Z, Hazer B, Denkbas EB. Prevention of urinary infection through the incorporation of silver-ricinoleic acid-polystyrene nanoparticles on the catheter surface. J Biomater Appl 2021; 36:385-405. [PMID: 33530824 DOI: 10.1177/0885328220983552] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Nosocominal infections associated with biofilm formation on urinary catheters cause serious complications. The aim of this study was to investigate the feasibility of the polyurethane (PU) catheter modified with tetracycline hydrochloride (TCH) attached Ag nanoparticles embedded PolyRicinoleic acid-Polystyrene Nanoparticles (PU-TCH-AgNPs-PRici-PS NPs) and the influence on antimicrobial and antibiofilm activity of urinary catheters infected by Escherichia coli and Staphylococcus aureus. For this purpose, AgNPs embedded PRici graft PS graft copolymers (AgNPs-PRici-g-PS) were synthesized via free radical polymerization and characterized by FTIR, HNMR and DSC. AgNPs-PRici-PS NPs were prepared and optimized by the different parameters and the optimized size of nanoparticle was found as about 150 ± 1 nm. The characterization of the nanoparticles and the morphological evaluation were carried out by FTIR and SEM. Short term stability of nanoparticles was realised at 4°C for 30 days. In vitro release profiles of TCH and Ag NPs were also investigated. The formation of biofilm on PU modified TCH-Ag NPs-PRici-PS NPs, was evaluated and the biocompatibility test of the nanoparticles was realized via the mouse fibroblast (L929) and mouse urinary bladder cells (G/G An1). This is the first time that TCH-AgNPs-PRici-PS NPs used in the modification of PU catheter demonstrated high antimicrobial and antibiofilm activities against the urinary tract infection.
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Affiliation(s)
- Hazal Koc
- Nanotechnology Engineering Department, Institute of Science, Bülent Ecevit University, Zonguldak, Turkey
| | - Ebru Kilicay
- Vocational School of Eldivan Health Services, Karatekin University, Cankiri, Turkey
| | | | - Baki Hazer
- Department of Aircraft Airflame Engine Maintenance, Kapadokya University, Ürgüp, Turkey.,Department of Chemistry, Bulent Ecevit University, Zonguldak, Turkey
| | - Emir B Denkbas
- Bioengineering Division, Institute of Pure and Applied Sciences, Hacettepe University, Ankara, Turkey.,Faculty of Engineering, Department of Biomedical Engineering, Başkent University, Ankara, Turkey
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Zhang Y, Qi J, Chen H, Xiong C. Amphiphilic diblock copolymers inhibit the formation of encrustation on the surface of biodegradable ureteral stents in vitro and in vivo. Colloids Surf A Physicochem Eng Asp 2021. [DOI: 10.1016/j.colsurfa.2020.125667] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Castelo-Branco DDSCM, Amando BR, Ocadaque CJ, Aguiar LD, Paiva DDDQ, Diógenes EM, Guedes GMDM, Costa CL, Santos-Filho ASP, Andrade ARCD, Cordeiro RDA, Rocha MFG, Sidrim JJC. Mini-review: from in vitro to ex vivo studies: an overview of alternative methods for the study of medical biofilms. BIOFOULING 2020; 36:1129-1148. [PMID: 33349038 DOI: 10.1080/08927014.2020.1859499] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Revised: 11/23/2020] [Accepted: 11/29/2020] [Indexed: 06/12/2023]
Abstract
Microbial biofilms are a natural adaptation of microorganisms, typically composed of multiple microbial species, exhibiting complex community organization and cooperation. Biofilm dynamics and their complex architecture are challenging for basic analyses, including the number of viable cells, biomass accumulation, biofilm morphology, among others. The methods used to study biofilms range from in vitro techniques to complex in vivo models. However, animal welfare has become a major concern, not only in society, but also in the academic and scientific field. Thus, the pursuit for alternatives to in vivo biofilm analyses presenting characteristics that mimic in vivo conditions has become essential. In this context, the present review proposes to provide an overview of strategies to study biofilms of medical interest, with emphasis on alternatives that approximate experimental conditions to host-associated environments, such as the use of medical devices as substrata for biofilm formation, microcosm and ex vivo models.
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Affiliation(s)
- Débora de Souza Collares Maia Castelo-Branco
- Department of Pathology and Legal Medicine, Postgraduate Program in Medical Microbiology, Group of Applied Medical Microbiology, Federal University of Ceará, Fortaleza, Brazil
- Department of Pathology and Legal Medicine, Postgraduate Program in Medical Microbiology, Specialized Medical Mycology Center, Federal University of Ceará, Fortaleza, Brazil
| | - Bruno Rocha Amando
- Department of Pathology and Legal Medicine, Postgraduate Program in Medical Microbiology, Group of Applied Medical Microbiology, Federal University of Ceará, Fortaleza, Brazil
| | - Crister José Ocadaque
- Department of Pathology and Legal Medicine, Postgraduate Program in Medical Microbiology, Group of Applied Medical Microbiology, Federal University of Ceará, Fortaleza, Brazil
| | - Lara de Aguiar
- Department of Pathology and Legal Medicine, Postgraduate Program in Medical Microbiology, Specialized Medical Mycology Center, Federal University of Ceará, Fortaleza, Brazil
- Postgraduate Program in Veterinary Sciences, College of Veterinary, State University of Ceará, Fortaleza, Brazil
| | - Débora Damásio de Queiroz Paiva
- Department of Pathology and Legal Medicine, Postgraduate Program in Medical Microbiology, Group of Applied Medical Microbiology, Federal University of Ceará, Fortaleza, Brazil
| | - Expedito Maia Diógenes
- Department of Pathology and Legal Medicine, Postgraduate Program in Medical Microbiology, Group of Applied Medical Microbiology, Federal University of Ceará, Fortaleza, Brazil
| | - Glaucia Morgana de Melo Guedes
- Department of Pathology and Legal Medicine, Postgraduate Program in Medical Microbiology, Group of Applied Medical Microbiology, Federal University of Ceará, Fortaleza, Brazil
- Department of Pathology and Legal Medicine, Postgraduate Program in Medical Microbiology, Specialized Medical Mycology Center, Federal University of Ceará, Fortaleza, Brazil
| | - Cecília Leite Costa
- Department of Pathology and Legal Medicine, Postgraduate Program in Medical Microbiology, Group of Applied Medical Microbiology, Federal University of Ceará, Fortaleza, Brazil
| | - Anísio Silvestre Pinheiro Santos-Filho
- Department of Pathology and Legal Medicine, Postgraduate Program in Medical Microbiology, Group of Applied Medical Microbiology, Federal University of Ceará, Fortaleza, Brazil
| | - Ana Raquel Colares de Andrade
- Department of Pathology and Legal Medicine, Postgraduate Program in Medical Microbiology, Specialized Medical Mycology Center, Federal University of Ceará, Fortaleza, Brazil
| | - Rossana de Aguiar Cordeiro
- Department of Pathology and Legal Medicine, Postgraduate Program in Medical Microbiology, Specialized Medical Mycology Center, Federal University of Ceará, Fortaleza, Brazil
| | - Marcos Fábio Gadelha Rocha
- Department of Pathology and Legal Medicine, Postgraduate Program in Medical Microbiology, Specialized Medical Mycology Center, Federal University of Ceará, Fortaleza, Brazil
- Postgraduate Program in Veterinary Sciences, College of Veterinary, State University of Ceará, Fortaleza, Brazil
| | - José Júlio Costa Sidrim
- Department of Pathology and Legal Medicine, Postgraduate Program in Medical Microbiology, Specialized Medical Mycology Center, Federal University of Ceará, Fortaleza, Brazil
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Kumari P, Nath Y, Murty US, Ravichandiran V, Mohan U. Sortase A Mediated Bioconjugation of Common Epitopes Decreases Biofilm Formation in Staphylococcus aureus. Front Microbiol 2020; 11:1702. [PMID: 32903711 PMCID: PMC7438799 DOI: 10.3389/fmicb.2020.01702] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Accepted: 06/29/2020] [Indexed: 11/13/2022] Open
Abstract
Staphylococcus aureus is one of the most notorious pathogens and is frequently associated with nosocomial infections imposing serious risk to immune-compromised patients. This is in part due to its ability to colonize at the surface of indwelling medical devices and biofilm formation. Combating the biofilm formation with antibiotics has its own challenges like higher values of minimum inhibitory concentrations. Here, we describe a new approach to target biofilm formation by Gram positive bacteria. Sortase A is a transpeptidase enzyme which is responsible for tagging of around ∼22 cell surface proteins onto the outer surface. These proteins play a major role in the bacterial virulence. Sortase A recognizes its substrate through LPXTG motif. Here, we use this approach to install the synthetic peptide substrates onS. aureus. Sortase A substrate mimic, 6His-LPETG peptide was synthesized using solid phase peptide chemistry. Incorporation of the peptide on the cell surface was measured using ELISA. Effect of peptide incubation on Staphylococcus aureus biofilm was also studied. 71.1% biofilm inhibition was observed with 100 μM peptide while on silicon coated rubber latex catheter, 45.82% inhibition was observed. The present work demonstrates the inability of surface modified S. aureus to establish biofilm formation thereby presenting a novel method for attenuating its virulence.
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Affiliation(s)
- Poonam Kumari
- Department of Biotechnology, National Institute of Pharmaceutical Education and Research, Guwahati, India
| | - Yutika Nath
- Department of Biotechnology, National Institute of Pharmaceutical Education and Research, Guwahati, India
| | | | - Velayutham Ravichandiran
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research, Kolkata, India
| | - Utpal Mohan
- Department of Medicinal Chemistry, National Institute of Pharmaceutical Education and Research, Kolkata, India
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Hong KW, Cheon YH, Moon K, Hong SI, Ryu BH, Cho OH, Bae IG. Comparison of the clinical characteristics and outcomes of bloodstream infections caused by Raoultella species and Klebsiella pneumoniae. Infect Dis (Lond) 2020; 52:489-497. [DOI: 10.1080/23744235.2020.1758764] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
Affiliation(s)
- Kyung-Wook Hong
- Department of Internal Medicine, Gyeongsang National University Hospital, Gyeongsang National University College of Medicine, Jinju, Republic of Korea
| | - Yun-Hong Cheon
- Department of Internal Medicine, Gyeongsang National University Hospital, Gyeongsang National University College of Medicine, Jinju, Republic of Korea
| | - Kyunglan Moon
- Department of Internal Medicine, Gyeongsang National University Hospital, Gyeongsang National University College of Medicine, Jinju, Republic of Korea
| | - Sun In Hong
- Department of Internal Medicine, Gyeongsang National University Changwon Hospital, Gyeongsang National University College of Medicine, Changwon, Republic of Korea
| | - Byung-Han Ryu
- Department of Internal Medicine, Gyeongsang National University Changwon Hospital, Gyeongsang National University College of Medicine, Changwon, Republic of Korea
| | - Oh-Hyun Cho
- Department of Internal Medicine, Gyeongsang National University Changwon Hospital, Gyeongsang National University College of Medicine, Changwon, Republic of Korea
| | - In-Gyu Bae
- Department of Internal Medicine, Gyeongsang National University Hospital, Gyeongsang National University College of Medicine, Jinju, Republic of Korea
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Abstract
Many pathogenic bacteria can form biofilm matrices that consist of complex molecules such as polysaccharides, proteins, and DNA. These biofilms help the bacteria to infect and colonize a host. Such biofilms may attach and develop on the surfaces of indwelling medical devices or other supportive environments. This study found that following double-strand breaks in their DNA, Klebsiella pneumoniae cells can form a novel type of biofilm with ring-like or discoid morphology. This biofilm structure, named the “R-biofilm,” helps protect the bacteria against adverse conditions such as exposure to ethanol, hydrogen peroxide, and UV radiation. Biofilms usually form when the density of bacteria increases during the middle to late periods of growth in culture, commonly induced by quorum-sensing systems. Biofilms attach to the surfaces of either living or nonliving objects and protect bacteria against antibiotics and a host’s immune system. Here, a novel type of biofilm (the “R-biofilm”) is reported. These biofilms were formed by clinically isolated Klebsiella pneumoniae strains following double-stranded-DNA breaks (DSBs), while undamaged bacteria did not form classic biofilms even in the later stages of growth. R-biofilms had a fixed ring-like or discoid shape with good ductility and could protect many living bacterial cells within. We show that extracellular proteins and DNAs released, probably by dead bacteria, were the core structural materials of R-biofilms. We anticipate that novel signaling pathways besides the bacterial SOS response are involved in R-biofilm formation. The observations in this study suggest a limitation to the use of the currently popular Cas9-mediated bactericidal tools to eliminate certain bacteria because the resulting DSBs may lead to the formation of these protective R-biofilms. IMPORTANCE Many pathogenic bacteria can form biofilm matrices that consist of complex molecules such as polysaccharides, proteins, and DNA. These biofilms help the bacteria to infect and colonize a host. Such biofilms may attach and develop on the surfaces of indwelling medical devices or other supportive environments. This study found that following double-strand breaks in their DNA, Klebsiella pneumoniae cells can form a novel type of biofilm with ring-like or discoid morphology. This biofilm structure, named the “R-biofilm,” helps protect the bacteria against adverse conditions such as exposure to ethanol, hydrogen peroxide, and UV radiation.
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Lin MF, Lin YY, Lan CY. Characterization of biofilm production in different strains of Acinetobacter baumannii and the effects of chemical compounds on biofilm formation. PeerJ 2020; 8:e9020. [PMID: 32523805 PMCID: PMC7261477 DOI: 10.7717/peerj.9020] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Accepted: 03/28/2020] [Indexed: 12/23/2022] Open
Abstract
Acinetobacter baumannii, an important emerging pathogen of nosocomial infections, is known for its ability to form biofilms. Biofilm formation increases the survival rate of A. baumannii on dry surfaces and may contribute to its persistence in the hospital environment, which increases the probability of nosocomial infections and outbreaks. This study was undertaken to characterize the biofilm production of different strains of A. baumannii and the effects of chemical compounds, especially antibiotics, on biofilm formation. In this study, no statistically significant relationship was observed between the ability to form a biofilm and the antimicrobial susceptibility of the A. baumannii clinical isolates. Biofilm formation caused by A. baumannii ATCC 17978 after gene knockout of two-component regulatory system gene baeR, efflux pump genes emrA/emrB and outer membrane coding gene ompA revealed that all mutant strains had less biofilm formation than the wild-type strain, which was further supported by the images from scanning electron microscopy and confocal laser scanning microscopy. The addition of amikacin, colistin, LL-37 or tannic acid decreased the biofilm formation ability of A. baumannii. In contrast, the addition of lower subinhibitory concentration tigecycline increased the biofilm formation ability of A. baumannii. Minimum biofilm eradication concentrations of amikacin, imipenem, colistin, and tigecycline were increased obviously for both wild type and multidrug resistant clinical strain A. baumannii VGH2. In conclusion, the biofilm formation ability of A. baumannii varied in different strains, involved many genes and could be influenced by many chemical compounds.
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Affiliation(s)
- Ming-Feng Lin
- Department of Medicine, National Taiwan University Hospital Chu-Tung Branch, Hsinchu County, Taiwan
| | - Yun-You Lin
- Institute of Molecular and Cellular Biology, National Tsing Hua University, Hsinchu, Taiwan
| | - Chung-Yu Lan
- Institute of Molecular and Cellular Biology, National Tsing Hua University, Hsinchu, Taiwan.,Department of Life Science, National Tsing Hua University, Hsinchu, Taiwan
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Disayathanoowat T, Li H, Supapimon N, Suwannarach N, Lumyong S, Chantawannakul P, Guo J. Different Dynamics of Bacterial and Fungal Communities in Hive-Stored Bee Bread and Their Possible Roles: A Case Study from Two Commercial Honey Bees in China. Microorganisms 2020; 8:microorganisms8020264. [PMID: 32075309 PMCID: PMC7074699 DOI: 10.3390/microorganisms8020264] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Revised: 02/13/2020] [Accepted: 02/13/2020] [Indexed: 12/13/2022] Open
Abstract
This study investigated both bacterial and fungal communities in corbicular pollen and hive-stored bee bread of two commercial honey bees, Apis mellifera and Apis cerana, in China. Although both honey bees favor different main floral sources, the dynamics of each microbial community is similar. During pH reduction in hive-stored bee bread, results from conventional culturable methods and next-generation sequencing showed a declining bacterial population but a stable fungal population. Different honey bee species and floral sources might not affect the core microbial community structure but could change the number of bacteria. Corbicular pollen was colonized by the Enterobacteriaceae bacterium (Escherichia-Shiga, Panteoa, Pseudomonas) group; however, the number of bacteria significantly decreased in hive-stored bee bread in less than 72 h. In contrast, Acinetobacter was highly abundant and could utilize protein sources. In terms of the fungal community, the genus Cladosporium remained abundant in both corbicular pollen and hive-stored bee bread. This filamentous fungus might encourage honey bees to reserve pollen by releasing organic acids. Furthermore, several filamentous fungi had the potential to inhibit both commensal/contaminant bacteria and the growth of pathogens. Filamentous fungi, in particular, the genus Cladosporium, could support pollen preservation of both honey bee species.
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Affiliation(s)
- Terd Disayathanoowat
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China;
- Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand; (N.S.); (N.S.); (S.L.); (P.C.)
- Research Center in Bioresources for Agriculture, Industry and Medicine, Chiang Mai University, Chiang Mai 50200, Thailand
- Research Center of Microbial Diversity and Sustainable Utilization, Chiang Mai University, Chiang Mai 50200, Thailand
- Correspondence: (T.D.); (J.G.)
| | - HuanYuan Li
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China;
| | - Natapon Supapimon
- Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand; (N.S.); (N.S.); (S.L.); (P.C.)
| | - Nakarin Suwannarach
- Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand; (N.S.); (N.S.); (S.L.); (P.C.)
- Research Center of Microbial Diversity and Sustainable Utilization, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Saisamorn Lumyong
- Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand; (N.S.); (N.S.); (S.L.); (P.C.)
- Research Center of Microbial Diversity and Sustainable Utilization, Chiang Mai University, Chiang Mai 50200, Thailand
- Academy of Science, The Royal Society of Thailand, Bangkok 10300, Thailand
| | - Panuwan Chantawannakul
- Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand; (N.S.); (N.S.); (S.L.); (P.C.)
- Research Center in Bioresources for Agriculture, Industry and Medicine, Chiang Mai University, Chiang Mai 50200, Thailand
| | - Jun Guo
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming 650500, China;
- Correspondence: (T.D.); (J.G.)
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Antifouling effect of water-soluble phosphate glass frit for filtration plants. Folia Microbiol (Praha) 2019; 65:363-370. [PMID: 31392507 DOI: 10.1007/s12223-019-00743-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Accepted: 07/29/2019] [Indexed: 10/26/2022]
Abstract
The antifouling, antimicrobial, elution behavior, skin irritant, and cytotoxicity properties of water-soluble phosphate glass on stainless steel were evaluated. Water-soluble phosphate glass samples with 35% Cu (mol/mol) were prepared by altering the network modifier (Na2O, K2O) and network former (P2O5, B2O3) compositions. The materials were melted at temperatures within the range of 850-950 °C. The melt was then quenched and ground into fine particles using a twin roll mill. The resulting water-soluble glasses were prepared as glass frit (size < 100 μm) using a sieve. The amorphous phase was determined by X-ray diffraction and differential thermal analysis. Water-soluble glasses with a reduced Cu ion elution rate of 1.2 ppm per week were formed because the chemical resistances of the formulated glasses improved as the P2O5 content decreased and the B2O3 content increased. To test its antifouling properties, the glass frit was mixed with paint and coated onto a STS316L sheet. The surface roughness was increased markedly from 1.4 to 19.2 nm, increasing the specific surface area for antimicrobial activity. It was demonstrated that the proposed method was able to form noncytotoxic, nonirritant, water-soluble glasses with 99.9% antimicrobial activity against Staphylococcus aureus. These results suggest that water-soluble phosphate glass on STS316L sheets could be useful in filtration plants.
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28
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A method to assess influence of different medical tubing on biofilm formation by Acinetobacter baumannii. J Microbiol Methods 2019; 160:84-86. [DOI: 10.1016/j.mimet.2019.03.023] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Revised: 03/25/2019] [Accepted: 03/26/2019] [Indexed: 02/03/2023]
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29
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das Neves RC, Mortari MR, Schwartz EF, Kipnis A, Junqueira-Kipnis AP. Antimicrobial and Antibiofilm Effects of Peptides from Venom of Social Wasp and Scorpion on Multidrug-Resistant Acinetobacter baumannii. Toxins (Basel) 2019; 11:E216. [PMID: 30974767 PMCID: PMC6520840 DOI: 10.3390/toxins11040216] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 03/28/2019] [Accepted: 04/04/2019] [Indexed: 02/07/2023] Open
Abstract
Intravascular stent infection is a rare complication with a high morbidity and high mortality; bacteria from the hospital environment form biofilms and are often multidrug-resistant (MDR). Antimicrobial peptides (AMPs) have been considered as alternatives to bacterial infection treatment. We analyzed the formation of the bacterial biofilm on the vascular stents and also tested the inhibition of this biofilm by AMPs to be used as treatment or coating. Antimicrobial activity and antibiofilm were tested with wasp (Agelaia-MPI, Polybia-MPII, Polydim-I) and scorpion (Con10 and NDBP5.8) AMPs against Acinetobacter baumannii clinical strains. A. baumannii formed a biofilm on the vascular stent. Agelaia-MPI and Polybia-MPII inhibited biofilm formation with bacterial cell wall degradation. Coating biofilms with polyethylene glycol (PEG 400) and Agelaia-MPI reduced 90% of A. baumannii adhesion on stents. The wasp AMPs Agelaia-MPI and Polybia-MPII had better action against MDR A. baumannii adherence and biofilm formation on vascular stents, preventing its formation and treating mature biofilm when compared to the other tested peptides.
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Affiliation(s)
- Rogério Coutinho das Neves
- Laboratory of Immunopathology of infectious diseases, Department of Immunology, Institute of Tropical Pathology and Public Health, Federal University of Goiás, Rua 235, Goiania, 74605-050 Goiás, Brazil.
| | - Márcia Renata Mortari
- Laboratory of Neuropharmacology, Department of Physiological Sciences, Institute of Biological Sciences, University of Brasília, 70910-900 Brasilia, Brazil.
| | - Elisabeth Ferroni Schwartz
- Laboratory of Neuropharmacology, Department of Physiological Sciences, Institute of Biological Sciences, University of Brasília, 70910-900 Brasilia, Brazil.
| | - André Kipnis
- Laboratory of Immunopathology of infectious diseases, Department of Immunology, Institute of Tropical Pathology and Public Health, Federal University of Goiás, Rua 235, Goiania, 74605-050 Goiás, Brazil.
| | - Ana Paula Junqueira-Kipnis
- Laboratory of Immunopathology of infectious diseases, Department of Immunology, Institute of Tropical Pathology and Public Health, Federal University of Goiás, Rua 235, Goiania, 74605-050 Goiás, Brazil.
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30
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Ramstedt M, Ribeiro IAC, Bujdakova H, Mergulhão FJM, Jordao L, Thomsen P, Alm M, Burmølle M, Vladkova T, Can F, Reches M, Riool M, Barros A, Reis RL, Meaurio E, Kikhney J, Moter A, Zaat SAJ, Sjollema J. Evaluating Efficacy of Antimicrobial and Antifouling Materials for Urinary Tract Medical Devices: Challenges and Recommendations. Macromol Biosci 2019; 19:e1800384. [PMID: 30884146 DOI: 10.1002/mabi.201800384] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 01/18/2019] [Indexed: 01/05/2023]
Abstract
In Europe, the mean incidence of urinary tract infections in intensive care units is 1.1 per 1000 patient-days. Of these cases, catheter-associated urinary tract infections (CAUTI) account for 98%. In total, CAUTI in hospitals is estimated to give additional health-care costs of £1-2.5 billion in the United Kingdom alone. This is in sharp contrast to the low cost of urinary catheters and emphasizes the need for innovative products that reduce the incidence rate of CAUTI. Ureteral stents and other urinary-tract devices suffer similar problems. Antimicrobial strategies are being developed, however, the evaluation of their efficacy is very challenging. This review aims to provide considerations and recommendations covering all relevant aspects of antimicrobial material testing, including surface characterization, biocompatibility, cytotoxicity, in vitro and in vivo tests, microbial strain selection, and hydrodynamic conditions, all in the perspective of complying to the complex pathology of device-associated urinary tract infection. The recommendations should be on the basis of standard assays to be developed which would enable comparisons of results obtained in different research labs both in industry and in academia, as well as provide industry and academia with tools to assess the antimicrobial properties for urinary tract devices in a reliable way.
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Affiliation(s)
| | - Isabel A C Ribeiro
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, 1649-004, Lisbon, Portugal
| | - Helena Bujdakova
- Department of Microbiology and Virology, Faculty of Natural Sciences, Comenius University in Bratislava, 81499, Bratislava 1, Slovakia
| | - Filipe J M Mergulhão
- Laboratory for Process Engineering, Environment, Biotechnology and Energy (LEPABE), Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465, Porto, Portugal
| | - Luisa Jordao
- Department of Environmental Health, Research and Development Unit, National Institute of Health Dr. Ricardo Jorge (INSA), Avenida Padre Cruz, 1649-016, Lisbon, Portugal
| | - Peter Thomsen
- BioModics ApS, Stengårds Alle 31A, DK-2800, Lyngby, Denmark
| | - Martin Alm
- BioModics ApS, Stengårds Alle 31A, DK-2800, Lyngby, Denmark
| | - Mette Burmølle
- Department of Biology, University of Copenhagen, 2100, Copenhagen, Denmark
| | - Todorka Vladkova
- Department of Polymers, University of Chemical Technology and Metallurgy (UCTM), 8 Kliment Ohridski Blvd, 1756, Sofia, Bulgaria
| | - Fusun Can
- Department of Medical Microbiology, School of Medicine, Koc University, 34450, Sariyer, Istanbul, Turkey
| | - Meital Reches
- Institute of Chemistry and the Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem, 91904, Israel
| | - Martijn Riool
- Department of Medical Microbiology, Amsterdam UMC, Amsterdam Infection and Immunity Institute, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Alexandre Barros
- 3B's Research Group, I3Bs Research Institute on Biomaterials, Biodegradables and Biomimetics, University of Minho, Guimarães, 4710-057, Braga, Portugal
| | - Rui L Reis
- 3B's Research Group, I3Bs Research Institute on Biomaterials, Biodegradables and Biomimetics, University of Minho, Guimarães, 4710-057, Braga, Portugal
| | - Emilio Meaurio
- Department of Mining-Metallurgy Engineering and Materials Science, POLYMAT, School of Engineering, University of the Basque Country, 48940 Leina, Bizkaia, Bilbao, Spain
| | - Judith Kikhney
- Biofilmcenter, Department of Microbiology, Infectious Diseases and Immunology, Charité University Medicine Berlin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Annette Moter
- Biofilmcenter, Department of Microbiology, Infectious Diseases and Immunology, Charité University Medicine Berlin, Hindenburgdamm 30, 12203, Berlin, Germany
| | - Sebastian A J Zaat
- Department of Medical Microbiology, Amsterdam UMC, Amsterdam Infection and Immunity Institute, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Jelmer Sjollema
- University of Groningen, University Medical Center Groningen, Department of Biomedical Engineering, Antonius Deusinglaan 1, 9713 AV, Groningen, The Netherlands
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Fabrication of an Original Transparent PVA/Gelatin Hydrogel: In Vitro Antimicrobial Activity against Skin Pathogens. INT J POLYM SCI 2019. [DOI: 10.1155/2019/7651810] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The design of actively efficient and low-toxicity formulations against virulent bacterial strains causing skin infections remains a challenging task. The aim of the present study was to develop and evaluate in vitro a hydrogel impregnated with a known plant extract for topical applications against major skin bacteria. A poly(vinyl alcohol) (PVA)/gelatin hydrogel, namely HG, was prepared by esterification following the solution casting method. The gelling process was realized by cross-linking the synthetic polymer PVA and the biopolymer gelatin in the presence of hydrochloric acid (HCl). A crude extract of Nigella sativa seeds was then encapsulated in HG, and the resulting HGE was characterized morphologically (by Scanning Electron Microscopy (SEM)), structurally (by X-ray powder diffraction (XRD) and Fourier Transform Infrared (FTIR) spectroscopy), behaviorally (by swelling behavior), and biologically (by the agar well diffusion method). The results of HGE were compared to HG and HG impregnated with 10% acetic acid (HGAA). SEM sections of HGE revealed a dense and porous surface, suggesting a good hydrophilicity. X-ray diffractograms indicated that HGE and HG had a similar degree of crystallinity. FTIR spectra confirmed that esterification occurred between PVA and gelatin suggesting that the amine group is involved in the intercalation of the plant extract components in HG. Further, HGE was found to be as wettable and swellable as HG, suggesting a good biocompatibility. Eventually, HGE exerted a pronounced inhibitory effect against two major skin pathogens, the Gram-negative Pseudomonas aeruginosa and the Gram-positive Staphylococcus aureus, suggesting a good extract release. Taken together, the experimental data indicated that HGE might be a promising wound dressing.
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32
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Nagaraj V, Skillman L, Li D, Ho G. Review - Bacteria and their extracellular polymeric substances causing biofouling on seawater reverse osmosis desalination membranes. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2018; 223:586-599. [PMID: 29975885 DOI: 10.1016/j.jenvman.2018.05.088] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Revised: 05/25/2018] [Accepted: 05/26/2018] [Indexed: 05/26/2023]
Abstract
Biofouling in seawater reverse osmosis (SWRO) membranes is a critical issue faced by the desalination industry worldwide. The major cause of biofouling is the irreversible attachment of recalcitrant biofilms formed by bacteria and their extracellular polymeric substances (EPS) on membrane surfaces. Transparent exopolymer particles (TEP) and protobiofilms are recently identified as important precursors of membrane fouling. Despite considerable amount of research on SWRO biofouling, the control of biofouling still remains a challenge. While adoption of better pretreatment methods may help in preventing membrane biofouling in new desalination setups, it is also crucial to effectively disperse old, recalcitrant biofilms and prolong membrane life in operational plants. Most current practices employ the use of broad spectrum biocides and chemicals that target bacterial cells to disperse mature biofilms, which are evidently inefficient. EPS, being known as the strongest structural framework of biofilms, it is essential to breakdown and disintegrate the EPS components for effective biofilm removal. To achieve this, it is necessary to understand the chemical composition and key elements that constitute the EPS of major biofouling bacterial groups in multi-species, mature biofilms. However, significant gaps in understanding the complexity of EPS are evident by the failure to achieve effective prevention and mitigation of fouling in most cases. Some of the reasons may be difficulty in sampling membranes from fully operational full-scale plants, poor understanding of microbial communities and their ecological shifts under dynamic operational conditions within the desalination process, selection of inappropriate model species for laboratory-scale biofouling studies, and the laborious process of extraction and purification of EPS. This article reviews the novel findings on key aspects of SWRO membrane fouling and control measures with particular emphasis on the key sugars in EPS. As a novel strategy to alleviate biofouling, future control methods may be aimed towards specifically disintegrating and breaking down these key sugars rather than using broad spectrum chemicals such as biocides that are currently used in the industry.
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Affiliation(s)
- Veena Nagaraj
- School of Engineering and Information Technology, Murdoch University, 90 South Street, Murdoch, Western Australia 6150, Australia.
| | - Lucy Skillman
- School of Engineering and Information Technology, Murdoch University, 90 South Street, Murdoch, Western Australia 6150, Australia.
| | - Dan Li
- School of Engineering and Information Technology, Murdoch University, 90 South Street, Murdoch, Western Australia 6150, Australia.
| | - Goen Ho
- School of Engineering and Information Technology, Murdoch University, 90 South Street, Murdoch, Western Australia 6150, Australia.
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Xu N, Wang G, Leng Y, Dong X, Chen F, Xing Q. Sulbactam enhances the in vitro activity of sitafloxacin against extensively-drug resistant Acinetobacter baumannii. Exp Ther Med 2018; 16:3485-3491. [PMID: 30233699 PMCID: PMC6143835 DOI: 10.3892/etm.2018.6630] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Accepted: 07/06/2018] [Indexed: 12/17/2022] Open
Abstract
The present study aimed to determine the in vitro activities of sulbactam and sitafloxacin against extensively-drug resistant Acinetobacter baumannii (XDR-A. baumannii). A total of 50 strains of XDR-A. baumannii were isolated from clinical specimens. Broth microdilution assay was applied to determine the minimum inhibitory concentration (MIC) for sulbactam and sitafloxacin. Microdilution checkerboard method was used to determine the in vitro activity of this antimicrobial combination. Accordingly, the fractional inhibitory concentration (FIC) and FIC index (FICI) were calculated. Time-kill study was also carried out for four strains with different susceptibilities to determine the bactericidal activities of individual or combined use of sitafloxacin and sulbactam. Isolates with MICs of sitafloxacin ≤2 mg/l were considered to be susceptible to sitafloxacin. The susceptibility rate for sitafloxacin was 92% originally. When combined with sulbactam, this rate increased to 96%. Microdilution checkerboard results indicated that, when tested in combination, sulbactam/sitafloxacin exhibited marked synergistic and partial synergistic effects on 16 and 50% of the 50 strains, respectively. Time-kill assay suggested that sulbactam enhanced the bactericidal activity of sitafloxacin and the combination induced a synergistic effect. For strains that were not susceptible to sitafloxacin, the bactericidal activities of the combination of sitafloxacin and sulbactam at a sub-MIC concentration were impaired. However, this impairment could be overcome with the increase of the concentration to 1X MIC. The present study demonstrated that sulbactam enhanced the in vitro antimicrobial activity of sitafloxacin against XDR-A. baumannii.
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Affiliation(s)
- Nannan Xu
- Department of Infectious Disease, Qilu Hospital, Shandong University, Jinan, Shandong 250012, P.R. China
| | - Gang Wang
- Department of Infectious Disease, Qilu Hospital, Shandong University, Jinan, Shandong 250012, P.R. China
| | - Yan Leng
- Center of Disease Control and Prevention of Shandong Province, Jinan, Shandong 250014, P.R. China
| | - Xiaomeng Dong
- Department of Infectious Disease, Qilu Hospital, Shandong University, Jinan, Shandong 250012, P.R. China
| | - Fengzhe Chen
- Department of Infectious Disease, Qilu Hospital, Shandong University, Jinan, Shandong 250012, P.R. China
| | - Quantai Xing
- Department of Infectious Disease, Qilu Hospital, Shandong University, Jinan, Shandong 250012, P.R. China
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34
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Buhmann MT, Abt D, Altenried S, Rupper P, Betschart P, Zumstein V, Maniura-Weber K, Ren Q. Extraction of Biofilms From Ureteral Stents for Quantification and Cultivation-Dependent and -Independent Analyses. Front Microbiol 2018; 9:1470. [PMID: 30050505 PMCID: PMC6052902 DOI: 10.3389/fmicb.2018.01470] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Accepted: 06/12/2018] [Indexed: 12/21/2022] Open
Abstract
Ureteral stenting is a common surgical procedure, which is associated with a high morbidity and economic burden, but the knowledge on the link between biofilms on these stents, morbidity, and the impact of the involved microbiota is still limited. This is partially due to a lack of methods that allow for a controlled extraction of the biofilms from stents. Development of an appropriate in vitro model to assess prevention of biofilm formation by antimicrobial coatings and biomaterials requires a profound understanding of the biofilm composition, including the involved microbiota. This work describes an analytical pipeline for the extraction of native biofilms from ureteral stents for both cultivation-dependent and -independent analysis, involving a novel mechanical abrasion method of passing stent samples through a tapered pinhole. The efficiency of this novel method was evaluated by quantifying the removed biofilm mass, numbers of cultivable bacteria, calcium content, and microscopic stent analysis after biofilm removal using 30 clinical stent samples. Furthermore, the extraction of in vitro formed Escherichia coli biofilms was evaluated by universal 16S quantitative PCR, a cultivation-independent method to demonstrate efficient biofilm removal by the new approach. The novel method enables effective contamination-free extraction of the biofilms formed on ureteral stents and their subsequent quantification, and it represents a useful tool for comprehensive examinations of biofilms on ureteral stents.
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Affiliation(s)
- Matthias T. Buhmann
- Laboratory for Biointerfaces, Empa, Swiss Federal Laboratories for Materials Science and Technology, St. Gallen, Switzerland
| | - Dominik Abt
- Department of Urology, Cantonal Hospital St. Gallen, St. Gallen, Switzerland
| | - Stefanie Altenried
- Laboratory for Biointerfaces, Empa, Swiss Federal Laboratories for Materials Science and Technology, St. Gallen, Switzerland
| | - Patrick Rupper
- Laboratory for Advanced Fibers, Empa, Swiss Federal Laboratories for Materials Science and Technology, St. Gallen, Switzerland
| | - Patrick Betschart
- Department of Urology, Cantonal Hospital St. Gallen, St. Gallen, Switzerland
| | - Valentin Zumstein
- Department of Urology, Cantonal Hospital St. Gallen, St. Gallen, Switzerland
| | - Katharina Maniura-Weber
- Laboratory for Biointerfaces, Empa, Swiss Federal Laboratories for Materials Science and Technology, St. Gallen, Switzerland
| | - Qun Ren
- Laboratory for Biointerfaces, Empa, Swiss Federal Laboratories for Materials Science and Technology, St. Gallen, Switzerland
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Eales MG, Ferrari E, Goddard AD, Lancaster L, Sanderson P, Miller C. Mechanistic and phenotypic studies of bicarinalin, BP100 and colistin action on Acinetobacter baumannii. Res Microbiol 2018; 169:296-302. [DOI: 10.1016/j.resmic.2018.04.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Revised: 04/20/2018] [Accepted: 04/20/2018] [Indexed: 01/10/2023]
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Narayanan A, Nair MS, Muyyarikkandy MS, Amalaradjou MA. Inhibition and Inactivation of Uropathogenic Escherichia coli Biofilms on Urinary Catheters by Sodium Selenite. Int J Mol Sci 2018; 19:ijms19061703. [PMID: 29880781 PMCID: PMC6032314 DOI: 10.3390/ijms19061703] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Revised: 05/23/2018] [Accepted: 06/05/2018] [Indexed: 01/09/2023] Open
Abstract
Urinary tract infections (UTI) are the most common hospital-acquired infections in humans and are caused primarily by uropathogenic Escherichia coli (UPEC). Indwelling urinary catheters become encrusted with UPEC biofilms that are resistant to common antibiotics, resulting in chronic infections. Therefore, it is important to control UPEC biofilms on catheters to reduce the risk for UTIs. This study investigated the efficacy of selenium for inhibiting and inactivating UPEC biofilms on urinary catheters. Urinary catheters were inoculated with UPEC and treated with 0 and 35 mM selenium at 37 °C for 5 days for the biofilm inhibition assay. In addition, catheters with preformed UPEC biofilms were treated with 0, 45, 60, and 85 mM selenium and incubated at 37 °C. Biofilm-associated UPEC counts on catheters were enumerated on days 0, 1, 3, and 5 of incubation. Additionally, the effect of selenium on exopolysacchride (EPS) production and expression of UPEC biofilm-associated genes was evaluated. Selenium at 35 mM concentration was effective in preventing UPEC biofilm formation on catheters compared to controls (p < 0.05). Further, this inhibitory effect was associated with a reduction in EPS production and UPEC gene expression. Moreover, at higher concentrations, selenium was effective in inactivating preformed UPEC biofilms on catheters as early as day 3 of incubation. Results suggest that selenium could be potentially used in the control of UPEC biofilms on urinary catheters.
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Affiliation(s)
- Amoolya Narayanan
- Department of Psychology, University of Connecticut, Storrs, CT 06269, USA.
| | - Meera S Nair
- Department of Animal Science, University of Connecticut, Storrs, CT 06269, USA.
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Van Cleve J, Boucher B, Smith D, Croce M. Ventilator associated pneumonia caused by Raoultella ornithinolytica in two immunocompetent trauma patients. Respir Med Case Rep 2018; 24:135-137. [PMID: 29977781 PMCID: PMC6010634 DOI: 10.1016/j.rmcr.2018.05.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 05/01/2018] [Indexed: 11/18/2022] Open
Abstract
Infections with Raoultella ornithinolytica have recently been reported more frequently in the medical literature. This pathogen has the potential to cause many types of infections, including pneumonia. Here, we report the first two cases of ventilator-associated pneumonia (VAP) in trauma patients caused by Raoultella ornithinolytica. Both of these infections were successfully treated with antibiotics based on susceptibilities and the patients were able to be transferred out of the intensive care unit.
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Affiliation(s)
- J.R. Van Cleve
- University of Tennessee, College of Pharmacy, USA
- Corresponding author.
| | - B.A. Boucher
- University of Tennessee, College of Pharmacy, USA
| | - D.V. Smith
- University of Tennessee, College of Pharmacy, USA
| | - M.A. Croce
- University of Tennessee, College of Medicine, Department of Surgery, USA
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Lam PW, Tadros M, Fong IW. Mandibular osteomyelitis due to Raoultella species. JMM Case Rep 2018; 5:e005140. [PMID: 29623214 PMCID: PMC5884960 DOI: 10.1099/jmmcr.0.005140] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Accepted: 01/12/2018] [Indexed: 11/26/2022] Open
Abstract
Introduction Raoultella is a genus of aerobic Gram-negative bacilli belonging to the family Enterobacteriaceae that are commonly found in water, soil and aquatic environments. With improved bacterial identification techniques, Raoultella species (namely R. planticola and R. ornithinolytica) have been an increasingly reported cause of infections in humans. Case presentation An 85-year-old man presented to hospital with a several-week history of left jaw pain and trismus. His medical history was significant for left mandibular osteomyelitis treated 1 year previously with amoxicillin-clavulanate. On admission, a computed tomography scan demonstrated a 2.6×1.7×1.6 cm peripherally enhancing collection surrounding the left posterior mandibular body. Two aspirates of the abscess grew a bacterium belonging to the genus Raoultella, with discordant species identification (R. ornithinolytica versus R. planticola) using two different techniques. A potential source of infection included a left lower molar tooth which was extracted months preceding the original diagnosis of osteomyelitis. Conclusion This is the first case of mandibular osteomyelitis caused by Raoultella species reported in the literature. In contrast to other forms of osteomyelitis, the pathogenesis of mandibular osteomyelitis involves contiguous spread from an odontogenic focus. Risk factors for mandibular osteomyelitis include a history of fracture, irradiation, diabetes and steroid therapy. This report adds to the growing literature of infections caused by this genus of bacteria, and raises the possibility of this organism’s role in odontogenic infections.
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Affiliation(s)
- Philip W Lam
- Department of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Manal Tadros
- Department of Medical Microbiology, St. Michael's Hospital, Toronto, Ontario, Canada
| | - Ignatius W Fong
- Department of Infectious Diseases, St. Michael's Hospital, Toronto, Ontario, Canada
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Bardbari AM, Arabestani MR, Karami M, Keramat F, Aghazadeh H, Alikhani MY, Bagheri KP. Highly synergistic activity of melittin with imipenem and colistin in biofilm inhibition against multidrug-resistant strong biofilm producer strains of Acinetobacter baumannii. Eur J Clin Microbiol Infect Dis 2018; 37:443-454. [DOI: 10.1007/s10096-018-3189-7] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Accepted: 01/08/2018] [Indexed: 01/10/2023]
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Morse DJ, Wilson MJ, Wei X, Lewis MAO, Bradshaw DJ, Murdoch C, Williams DW. Denture-associated biofilm infection in three-dimensional oral mucosal tissue models. J Med Microbiol 2018; 67:364-375. [PMID: 29458673 PMCID: PMC5882079 DOI: 10.1099/jmm.0.000677] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Purpose In vitro analyses of virulence, pathogenicity and associated host cell responses are important components in the study of biofilm infections. The Candida-related infection, denture-associated oral candidosis, affects up to 60 % of denture wearers and manifests as inflammation of palatal tissues contacting the denture-fitting surface. Commercially available three-dimensional tissue models can be used to study infection, but their use is limited for many academic research institutions, primarily because of the substantial purchase costs. The aim of this study was to develop and evaluate the use of in vitro tissue models to assess infections by biofilms on acrylic surfaces through tissue damage and Candida albicans virulence gene expression. Methodology In vitro models were compared against commercially available tissue equivalents (keratinocyte-only, SkinEthic; full-thickness, MatTek Corporation). An in vitro keratinocyte-only tissue was produced using a cancer-derived cell line, TR146, and a full-thickness model incorporating primary fibroblasts and immortalised normal oral keratinocytes was also generated. The in vitro full-thickness tissues incorporated keratinocytes and fibroblasts, and have potential for future further development and analysis. Results Following polymicrobial infection with biofilms on acrylic surfaces, both in-house developed models were shown to provide equivalent results to the SkinEthic and MatTek models in terms of tissue damage: a significant (P<0.05) increase in LDH activity for mixed species biofilms compared to uninfected control, and no significant difference (P>0.05) in the expression of most C. albicans virulence genes when comparing tissue models of the same type. Conclusion Our results confirm the feasibility and suitability of using these alternative in vitro tissue models for such analyses.
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Affiliation(s)
- Daniel J Morse
- Oral and Biomedical Sciences, School of Dentistry, Cardiff University, Cardiff, UK
| | - Melanie J Wilson
- Oral and Biomedical Sciences, School of Dentistry, Cardiff University, Cardiff, UK
| | - Xiaoqing Wei
- Oral and Biomedical Sciences, School of Dentistry, Cardiff University, Cardiff, UK
| | - Michael A O Lewis
- Oral and Biomedical Sciences, School of Dentistry, Cardiff University, Cardiff, UK
| | | | - Craig Murdoch
- School of Clinical Dentistry, University of Sheffield, Sheffield, UK
| | - David W Williams
- Oral and Biomedical Sciences, School of Dentistry, Cardiff University, Cardiff, UK
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Uzair B, Menaa F, Khan BA, Mohammad FV, Ahmad VU, Djeribi R, Menaa B. Isolation, purification, structural elucidation and antimicrobial activities of kocumarin, a novel antibiotic isolated from actinobacterium Kocuria marina CMG S2 associated with the brown seaweed Pelvetia canaliculata. Microbiol Res 2018; 206:186-197. [PMID: 29146256 DOI: 10.1016/j.micres.2017.10.007] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Revised: 10/10/2017] [Accepted: 10/17/2017] [Indexed: 12/20/2022]
Abstract
AIMS Screening of seaweed-associated bacteria capable of producing antimicrobials. METHODS AND RESULTS Fifteen microbial strains, associated to the brown seaweed Pelvetia canaliculata (Linnaeus) attached to the rocks of Sonmiani Beach (Karachi, Pakistan), were screened. Crude extract filtrates of CMG S2 strain grew on Zobell marine agar (ZMA) had the most remarkable antimicrobial activity. Based on its phenotypic aspects (e.g. Gram-positive, microccoid form), biochemical characteristics (e.g. halotolerance) and genetic analyses, CMG S2 is identified as a putatively new Kocuria marina type strain belonging to the actinobacteria's class and micrococcaceae family. Thereby, the nucleotide sequence analysis of its full-length 16S ribosomal ribonucleic acid (rRNA) gene (GenBank accession number EU073966.1) displayed highest identity (i.e. 99%) and score (2630) with K. marina KMM 3905. Phylogenic trees analysis using the neighbor-joining method showed closest evolutionary distance of CMG S2 with KMM 3905 strain and K. carniphila (DC2201) specie. Interestingly, a unique ultraviolet (UV)-bioactive compound was purified from CMG S2 crude extracts by flash silica gel column and thin-layer chromatography (TLC) techniques. Its chemical structure was unraveled as 4-[(Z)-2 phenyl ethenyl] benzoic acid (PEBA, later named kocumarin) by nuclear magnetic resonance (NMR) spectroscopy techniques. Importantly, kocumarin demonstrated prominent and rapid growth inhibition against all tested fungi and pathogenic bacteria including methicillin-resistant Staphylococcus aureus (MRSA), with a minimal fungal inhibitory concentration (MFC) of 15-25μg/mL and a minimal (bacterial) inhibitory concentration (MIC) of 10-15μg/mL. SIGNIFICANCE AND IMPACT OF THE STUDY Kocumarin represents a new promising natural antibiotic for in vivo and environmental applications.
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Affiliation(s)
- Bushra Uzair
- Department of Bioinformatics and Biotechnology, International Islamic University, Islamabad, Pakistan.
| | - Farid Menaa
- Department of Advanced Technologies, California Innovations Corporation, San Diego, CA, United States.
| | - Barkat Ali Khan
- Faculty of Pharmacy and Alternative Medicine, The Islamia University of Bahawalpur, Pakistan
| | | | - Viqar Uddin Ahmad
- H.E.J. Research Institute of Biological and Chemical Science, Karachi, Pakistan
| | - Ryad Djeribi
- Biofilms and Biocontamination of Materials, Annaba University, Algeria
| | - Bouzid Menaa
- Department of Advanced Technologies, California Innovations Corporation, San Diego, CA, United States
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González-Castro A, Rodríguez-Borregán JC, Campos S, Pérez Canga JL. Catheter-related bacteraemia caused by Raoultella ornithinolytica. ACTA ACUST UNITED AC 2017; 65:116-118. [PMID: 29162280 DOI: 10.1016/j.redar.2017.09.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Revised: 09/17/2017] [Accepted: 09/18/2017] [Indexed: 11/29/2022]
Abstract
Infections in humans by Raoultella spp. are rare and the effect that Raoultella spp. might have as a human pathogen is currently unknown. A clinical case is presented of catheter-related bacteraemia caused by Raoultella ornithinolytica, treated successfully with applied antibiotic therapy (intravenous cefepime and sealed the catheter with amikacin).
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Affiliation(s)
- A González-Castro
- Servicio de Medicina Intensiva, Hospital Universitario Marqués de Valdecilla, Santander, España.
| | - J C Rodríguez-Borregán
- Servicio de Medicina Intensiva, Hospital Universitario Marqués de Valdecilla, Santander, España
| | - S Campos
- Servicio de Medicina Intensiva, Hospital Universitario Marqués de Valdecilla, Santander, España
| | - J L Pérez Canga
- Servicio de Nefrología, Hospital Universitario Marqués de Valdecilla, Santander, España
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Antibiotic resistance of pathogenic Acinetobacter species and emerging combination therapy. J Microbiol 2017; 55:837-849. [PMID: 29076065 DOI: 10.1007/s12275-017-7288-4] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 09/19/2017] [Accepted: 09/20/2017] [Indexed: 01/08/2023]
Abstract
The increasing antibiotic resistance of Acinetobacter species in both natural and hospital environments has become a serious problem worldwide in recent decades. Because of both intrinsic and acquired antimicrobial resistance (AMR) against last-resort antibiotics such as carbapenems, novel therapeutics are urgently required to treat Acinetobacter-associated infectious diseases. Among the many pathogenic Acinetobacter species, A. baumannii has been reported to be resistant to all classes of antibiotics and contains many AMR genes, such as bla ADC (Acinetobacter-derived cephalosporinase). The AMR of pathogenic Acinetobacter species is the result of several different mechanisms, including active efflux pumps, mutations in antibiotic targets, antibiotic modification, and low antibiotic membrane permeability. To overcome the limitations of existing drugs, combination theraphy that can increase the activity of antibiotics should be considered in the treatment of Acinetobacter infections. Understanding the molecular mechanisms behind Acinetobacter AMR resistance will provide vital information for drug development and therapeutic strategies using combination treatment. Here, we summarize the classic mechanisms of Acinetobacter AMR, along with newly-discovered genetic AMR factors and currently available antimicrobial adjuvants that can enhance drug efficacy in the treatment of A. baumannii infections.
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Lalitha C, Raman T, Rathore SS, Ramar M, Munusamy A, Ramakrishnan J. ASK2 Bioactive Compound Inhibits MDR Klebsiella pneumoniae by Antibiofilm Activity, Modulating Macrophage Cytokines and Opsonophagocytosis. Front Cell Infect Microbiol 2017; 7:346. [PMID: 28824881 PMCID: PMC5543099 DOI: 10.3389/fcimb.2017.00346] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Accepted: 07/20/2017] [Indexed: 01/17/2023] Open
Abstract
The emergence and spread of pathogens harboring extended spectrum beta-lactamase (ESBL) like carbapenem resistant Gram negative bacteria are the major emerging threat to public health. Of particular concern Klebsiella pneumoniae carbapenamase- producing strains have been recorded worldwide. Catheter associated urinary tract infections (CAUTI) caused by K. pneumoniae are significantly associated with morbidity and mortality. Hence the present work was aimed to develop a strategy for addressing these issues through an innovative approach of antibiofilm and immunomodulation. These two independent activities were analyzed in a Streptomyces derived ASK2 bioactive compound. While analysing the effect of sub-minimum inhibitory concentrations (sub-MICs), 0.5x of Minimum Inhibitory Concentration (MIC) was found to be more effective in preventing biofilm formation on coverslip and silicone catheter. The minimum biofilm eradication concentration (MBEC) was found to be 15-fold higher MIC with eradication of 75% of 3 day old biofilm. Apart from its antibiofilm potential, ASK2 also acts as an opsonin and enhances phagocytic response of macrophages against multidrug resistant K. pneumoniae. In addition, ASK2 resulted in elevated levels of nitric oxide generation by the macrophages and has a stimulating effect on IL-12, IFN-γ, and TNF-α proinflammatory cytokines. The opsonic role of ASK2 and its potential in modulating proinflammatory cytokines secreted by macrophages implies the importance of ASK2 in modulating cellular immune response of macrophages against MDR K. pneumoniae. The present study proposes ASK2 as a promising candidate for treating MDR K. pneumoniae infections with its dual properties of antibiofilm and immunomodulatory activities.
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Affiliation(s)
- Cheepurupalli Lalitha
- Centre for Research in Infectious Diseases, School of Chemical and Biotechnology, SASTRA UniversityThanjavur, India
| | - Thiagarajan Raman
- Centre for Research in Infectious Diseases, School of Chemical and Biotechnology, SASTRA UniversityThanjavur, India
| | - Sudarshan S Rathore
- Centre for Research in Infectious Diseases, School of Chemical and Biotechnology, SASTRA UniversityThanjavur, India
| | | | | | - Jayapradha Ramakrishnan
- Centre for Research in Infectious Diseases, School of Chemical and Biotechnology, SASTRA UniversityThanjavur, India
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Shim K, Abdellatif M, Choi E, Kim D. Nanostructured ZnO films on stainless steel are highly safe and effective for antimicrobial applications. Appl Microbiol Biotechnol 2017; 101:2801-2809. [DOI: 10.1007/s00253-017-8099-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Revised: 12/20/2016] [Accepted: 12/27/2016] [Indexed: 11/29/2022]
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Vuotto C, Grosso F, Longo F, Balice MP, de Barros MC, Peixe L, Donelli G. Biofilm-Forming Ability and Clonality in Acinetobacter baumannii Strains Isolated from Urine Samples and Urinary Catheters in Different European Hospitals. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017. [PMID: 28639245 DOI: 10.1007/5584_2017_70] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
OBJECTIVE Biofilm formation has been associated with the persistence of Acinetobacter baumannii in hospital settings and its propensity to cause infection. We investigated the adhesion ability and clonality of 128 A. baumannii isolates recovered from urine and urinary catheters of patients admitted to 5 European hospitals during 1991-2013. METHODS Isolates identification was confirmed by rpoB sequencing and by the presence of blaOXA-51. The presence of carbapenemases was detected by PCR. Clonality was determined by Sequence Group (SG) identification, Pulsed field gel electrophoresis (PFGE) and Multilocus sequence typing. Adhesion ability was defined by quantitative biofilm production assay and biofilms were characterized by Confocal Laser Microscopy and Scanning Electron Microscopy. RESULTS The 128 isolates, either resistant (85.9%) or susceptible (14.1%) to carbapenems, and belonging to 50 different PFGE types and 24 different STs, were distributed among SG1 (67.2%), SG2 (10.2%) and other allelic profiles (22.7%). ST218 was the most frequent ST, corresponding to 54,5% of the isolates collected between 2011 and 2013. Among the 109 isolates showing resistance to at least 1 carbapenem, 55% revealed the presence of an acquired carbapenem-hydrolyzing class D - lactamases (CHDL): blaOXA-23 were the most frequent gene detected from 2008 onwards (75%). Among all the clinical isolates, 42.2% were strong biofilm producers, with the older isolates having the highest adhesion ability. Most isolates recovered later, belonging to ST218 and harbouring blaOXA-23, were homogeneously less adhesive. CONCLUSIONS An evolution towards a decrease in adhesion ability and a CHDL content change was observed along the years in several European countries.
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Affiliation(s)
- Claudia Vuotto
- Microbial Biofilm Laboratory, IRCCS Fondazione Santa Lucia, Rome, Italy.
| | - Filipa Grosso
- REQUIMTE. Laboratório de Microbiologia, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal
| | - Francesca Longo
- Microbial Biofilm Laboratory, IRCCS Fondazione Santa Lucia, Rome, Italy
| | - Maria Pia Balice
- Clinical Microbiology Laboratory, IRCCS Fondazione Santa Lucia, Rome, Italy
| | - Mariana Carvalho de Barros
- Microbial Biofilm Laboratory, IRCCS Fondazione Santa Lucia, Rome, Italy.,REQUIMTE. Laboratório de Microbiologia, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal
| | - Luisa Peixe
- REQUIMTE. Laboratório de Microbiologia, Faculdade de Farmácia, Universidade do Porto, Porto, Portugal
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Zhang Y, He W, Li J, Wang K, Li J, Tan H, Fu Q. Gemini quaternary ammonium salt waterborne biodegradable polyurethanes with antibacterial and biocompatible properties. MATERIALS CHEMISTRY FRONTIERS 2017. [DOI: 10.1039/c6qm00039h] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Novel antibacterial waterborne polyurethanes based on gemini quaternary ammonium salt with good biodegradable and biocompatible properties.
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Affiliation(s)
- Yi Zhang
- College of Polymer Science and Engineering
- State Key Laboratory of Polymer Materials Engineering
- Sichuan University
- Chengdu 610065
- China
| | - Wei He
- College of Polymer Science and Engineering
- State Key Laboratory of Polymer Materials Engineering
- Sichuan University
- Chengdu 610065
- China
| | - Jiehua Li
- College of Polymer Science and Engineering
- State Key Laboratory of Polymer Materials Engineering
- Sichuan University
- Chengdu 610065
- China
| | - Kunjie Wang
- Department of Urology
- West China Hospital
- Huaxi Clinical College
- Sichuan University
- Chengdu 610065
| | - Jianshu Li
- College of Polymer Science and Engineering
- State Key Laboratory of Polymer Materials Engineering
- Sichuan University
- Chengdu 610065
- China
| | - Hong Tan
- College of Polymer Science and Engineering
- State Key Laboratory of Polymer Materials Engineering
- Sichuan University
- Chengdu 610065
- China
| | - Qiang Fu
- College of Polymer Science and Engineering
- State Key Laboratory of Polymer Materials Engineering
- Sichuan University
- Chengdu 610065
- China
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Abstract
Strains of Klebsiella pneumoniae are frequently opportunistic pathogens implicated in urinary tract and catheter-associated urinary-tract infections of hospitalized patients and compromised individuals. Infections are particularly difficult to treat since most clinical isolates exhibit resistance to several antibiotics leading to treatment failure and the possibility of systemic dissemination. Infections of medical devices such as urinary catheters is a major site of K. pneumoniae infections and has been suggested to involve the formation of biofilms on these surfaces. Over the last decade there has been an increase in research activity designed to investigate the pathogenesis of K. pneumoniae in the urinary tract. These investigations have begun to define the bacterial factors that contribute to growth and biofilm formation. Several virulence factors have been demonstrated to mediate K. pneumoniae infectivity and include, but are most likely not limited to, adherence factors, capsule production, lipopolysaccharide presence, and siderophore activity. The development of both in vitro and in vivo models of infection will lead to further elucidation of the molecular pathogenesis of K. pneumoniae. As for most opportunistic infections, the role of host factors as well as bacterial traits are crucial in determining the outcome of infections. In addition, multidrug-resistant strains of these bacteria have become a serious problem in the treatment of Klebsiella infections and novel strategies to prevent and inhibit bacterial growth need to be developed. Overall, the frequency, significance, and morbidity associated with K. pneumoniae urinary tract infections have increased over many years. The emergence of these bacteria as sources of antibiotic resistance and pathogens of the urinary tract present a challenging problem for the clinician in terms of management and treatment of individuals.
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49
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Cooper IR, Pollini M, Paladini F. The potential of photo-deposited silver coatings on Foley catheters to prevent urinary tract infections. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2016; 69:414-20. [DOI: 10.1016/j.msec.2016.07.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Revised: 06/24/2016] [Accepted: 07/04/2016] [Indexed: 11/30/2022]
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50
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Galván EM, Mateyca C, Ielpi L. Role of interspecies interactions in dual-species biofilms developed in vitro by uropathogens isolated from polymicrobial urinary catheter-associated bacteriuria. BIOFOULING 2016; 32:1067-1077. [PMID: 27642801 DOI: 10.1080/08927014.2016.1231300] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/29/2016] [Accepted: 08/25/2016] [Indexed: 06/06/2023]
Abstract
Most catheter-associated urinary tract infections are polymicrobial. Here, uropathogen interactions in dual-species biofilms were studied. The dual-species associations selected based on their prevalence in clinical settings were Klebsiella pneumoniae-Escherichia coli, E. coli-Enterococcus faecalis, K. pneumoniae-E. faecalis, and K. pneumoniae-Proteus mirabilis. All species developed single-species biofilms in artificial urine. The ability of K. pneumoniae to form biofilms was not affected by E. coli or E. faecalis co-inoculation, but was impaired by P. mirabilis. Conversely, P. mirabilis established a biofilm when co-inoculated with K. pneumoniae. Additionally, E. coli persistence in biofilms was hampered by K. pneumoniae but not by E. faecalis. Interestingly, E. coli, but not K. pneumoniae, partially inhibited E. faecalis attachment to the surface and retarded biofilm development. The findings reveal bacterial interactions between uropathogens in dual-species biofilms ranged from affecting initial adhesion to outcompeting one bacterial species, depending on the identity of the partners involved.
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Affiliation(s)
- E M Galván
- a Laboratory of Bacterial Genetics , Fundacion Instituto Leloir-IIBBA (CONICET) , Buenos Aires , Argentina
| | - C Mateyca
- a Laboratory of Bacterial Genetics , Fundacion Instituto Leloir-IIBBA (CONICET) , Buenos Aires , Argentina
| | - L Ielpi
- a Laboratory of Bacterial Genetics , Fundacion Instituto Leloir-IIBBA (CONICET) , Buenos Aires , Argentina
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