401
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Hawkins ML, Schott SS, Grigoryan B, Rufin MA, Ngo BKD, Vanderwal L, Stafslien SJ, Grunlan MA. Anti-protein and anti-bacterial behavior of amphiphilic silicones. Polym Chem 2017; 8:5239-5251. [PMID: 29104619 PMCID: PMC5667680 DOI: 10.1039/c7py00944e] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Silicones with improved water-driven surface hydrophilicity and anti-biofouling behavior were achieved when bulk-modified with poly(ethylene oxide) (PEO) -silane amphiphiles of varying siloxane tether length: α-(EtO)3Si-(CH2)2-oligodimethylsiloxane m -block-poly(ethylene oxide)8-OCH3 (m = 0, 4, 13, 17, 24, and 30). A PEO8-silane [α-(EtO)3Si-(CH2)3-PEO8-OCH3] served as a conventional PEO-silane control. To examine anti-biofouling behavior in the absence versus presence of water-driven surface restructuring, the amphiphiles and control were surface-grafted onto silicon wafers and used to bulk-modify a medical-grade silicone, respectively. While the surface-grafted PEO-control exhibited superior protein resistance, it failed to appreciably restructure to the surface-water interface of bulk-modified silicone and thus led to poor protein resistance. In contrast, the PEO-silane amphiphiles, while less protein-resistant when surface-grafted onto silicon wafers, rapidly and substantially restructured in bulk-modified silicone, exhibiting superior hydrophilicity and protein resistance. A reduction of biofilm for several strains of bacteria and a fungus was observed for silicones modified with PEO-silane amphiphiles. Longer siloxane tethers maintained surface restructuring and protein resistance while displaying the added benefit of increased transparency.
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Affiliation(s)
- Melissa L Hawkins
- Department of Biomedical Engineering, Texas A&M University, College Station, TX 77843-3120
| | - Samantha S Schott
- Department of Biomedical Engineering, Texas A&M University, College Station, TX 77843-3120
| | - Bagrat Grigoryan
- Department of Biomedical Engineering, Texas A&M University, College Station, TX 77843-3120
| | - Marc A Rufin
- Department of Biomedical Engineering, Texas A&M University, College Station, TX 77843-3120
| | - Bryan Khai D Ngo
- Department of Biomedical Engineering, Texas A&M University, College Station, TX 77843-3120
| | - Lyndsi Vanderwal
- Office of Research & Creative Activity, North Dakota State University, Fargo, ND 58102
| | - Shane J Stafslien
- Office of Research & Creative Activity, North Dakota State University, Fargo, ND 58102
| | - Melissa A Grunlan
- Department of Biomedical Engineering, Texas A&M University, College Station, TX 77843-3120
- Department of Materials Science and Engineering, Texas A&M University, College Station, TX 77843-300
- Center for Remote Health Technologies System, Texas A&M University, College Station, TX 77843-3120
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402
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Porosa L, Caschera A, Bedard J, Mocella A, Ronan E, Lough AJ, Wolfaardt G, Foucher DA. UV-Curable Contact Active Benzophenone Terminated Quaternary Ammonium Antimicrobials for Applications in Polymer Plastics and Related Devices. ACS APPLIED MATERIALS & INTERFACES 2017; 9:27491-27503. [PMID: 28777541 DOI: 10.1021/acsami.7b07363] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
A series of UV active benzophenone ([C6H5COC6H4-O-(CH2)n-N+Me2R][X-]; 4, R = C12H25, n = 3, X- = Br-; 5a-c, R = C18H37, n = 3, X- = Cl-, Br-, I-; 6a-c, R = C18H37, n = 4, X- = Cl-, Br-, I-; 7a-c, R = C18H37, n = 6, X- = Cl-, Br-, I-) terminated C12 and C18 quaternary ammonium salts (QACs) were prepared by thermal or microwave-driven Menshutkin protocols of the appropriate benzophenone alkyl halide (1a-c, 2a-c, 3a-c) with the corresponding dodecyl- or octadecyl N,N-dimethylamine. All new compounds were characterized by NMR spectroscopy, HRMS spectrometry, and, in one instance (4), by single-crystal X-ray crystallography. Representative C12 and C18 benzophenone QACs were formulated into 1% (w/v) water or water/ethanol-based aerosol spray coatings and then UV-cured onto plastic substrates (polypropylene, polyethylene, polystyrene, polyvinyl chloride, and polyether ether ketone) with exposure to low to moderate doses of UV (20-30 J cm-2). Confirmation as to the presence of the coatings was detected by advancing water contact angle measurements, which revealed a more hydrophilic surface after coating. Further confirmation was gained by X-ray photoelectron spectroscopy analysis, time of flight secondary ion mass spectrometry, and bromophenol blue staining, all of which showed the presence of the attached quaternary ammonium molecule. Analysis of surfaces treated with the C18 benzophenone 5b by atomic force microscopy and surface profilometry revealed a coating thickness of ∼350 nm. The treated samples along with controls were then evaluated for their antimicrobial efficacy against Gram-positive (Arthrobacter sp., Listeria monocytogenes) and Gram-negative (Pseudomonas aeruginosa) bacteria at a solid/air interface using the large drop inoculum protocol; this technique gave no evidence for cell adhesion after a 3 h time frame. These antimicrobial materials show promise for their use as coatings on plastic biomedical devices with the aim of preventing biofilm formation and preventing the spread of hospital acquired infections.
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Affiliation(s)
- Lukas Porosa
- Department of Chemistry and Biology, Ryerson University , 350 Victoria Street, Toronto, Ontario M5B 2K3, Canada
| | - Alexander Caschera
- Department of Chemistry and Biology, Ryerson University , 350 Victoria Street, Toronto, Ontario M5B 2K3, Canada
| | - Joseph Bedard
- Department of Chemistry and Biology, Ryerson University , 350 Victoria Street, Toronto, Ontario M5B 2K3, Canada
| | - Amanda Mocella
- Department of Chemistry and Biology, Ryerson University , 350 Victoria Street, Toronto, Ontario M5B 2K3, Canada
| | - Evan Ronan
- Department of Chemistry and Biology, Ryerson University , 350 Victoria Street, Toronto, Ontario M5B 2K3, Canada
| | - Alan J Lough
- Department of Chemistry, University of Toronto , 80 St. George Street, Toronto, Ontario M5S 3H6, Canada
| | - Gideon Wolfaardt
- Department of Chemistry and Biology, Ryerson University , 350 Victoria Street, Toronto, Ontario M5B 2K3, Canada
- Stellenbosch University Water Institute Secretariat, Faculty of Natural Science, Stellenbosch Central , Stellenbosch 7599, South Africa
| | - Daniel A Foucher
- Department of Chemistry and Biology, Ryerson University , 350 Victoria Street, Toronto, Ontario M5B 2K3, Canada
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403
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Murray J, Muruko T, Gill CIR, Kearney MP, Farren D, Scott MG, McMullan G, Ternan NG. Evaluation of bactericidal and anti-biofilm properties of a novel surface-active organosilane biocide against healthcare associated pathogens and Pseudomonas aeruginosa biolfilm. PLoS One 2017; 12:e0182624. [PMID: 28787014 PMCID: PMC5546580 DOI: 10.1371/journal.pone.0182624] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Accepted: 07/21/2017] [Indexed: 11/18/2022] Open
Abstract
Healthcare acquired infections (HAI) pose a great threat in hospital settings and environmental contamination can be attributed to the spread of these. De-contamination and, significantly, prevention of re-contamination of the environment could help in preventing/reducing this threat. Goldshield (GS5) is a novel organosilane biocide marketed as a single application product with residual biocidal activity. We tested the hypothesis that GS5 could provide longer-term residual antimicrobial activity than existing disinfectants once applied to surfaces. Thus, the residual bactericidal properties of GS5, Actichlor and Distel against repeated challenge with Staphylococcus aureus ATCC43300 were tested, and showed that GS5 alone exhibited longer-term bactericidal activity for up to 6 days on 316I stainless steel surfaces. Having established efficacy against S. aureus, we tested GS5 against common healthcare acquired pathogens, and demonstrated that, on average, a 1 log10 bactericidal effect was exhibited by GS5 treated surfaces, although biocidal activity varied depending upon the surface type and the species of bacteria. The ability of GS5 to prevent Pseudomonas aeruginosa biofilm formation was measured in standard microtitre plate assays, where it had no significant effect on either biofilm formation or development. Taken together the data suggests that GS5 treatment of surfaces may be a useful means to reducing bacterial contamination in the context of infection control practices.
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Affiliation(s)
- Jason Murray
- Nutrition Innovation Centre for food and HEalth (NICHE), School of Biomedical Sciences, University of Ulster, Coleraine, Co. Londonderry, Northern Ireland, United Kingdom
| | - Tendai Muruko
- Nutrition Innovation Centre for food and HEalth (NICHE), School of Biomedical Sciences, University of Ulster, Coleraine, Co. Londonderry, Northern Ireland, United Kingdom
| | - Chris I. R. Gill
- Nutrition Innovation Centre for food and HEalth (NICHE), School of Biomedical Sciences, University of Ulster, Coleraine, Co. Londonderry, Northern Ireland, United Kingdom
| | - M. Patricia Kearney
- Northern Health and Social Care Trust, Antrim area Hospital, Bush House, Antrim, Co. Antrim, Northern Ireland, United Kingdom
| | - David Farren
- Northern Health and Social Care Trust, Antrim area Hospital, Bush House, Antrim, Co. Antrim, Northern Ireland, United Kingdom
| | - Michael G. Scott
- Northern Health and Social Care Trust, Antrim area Hospital, Bush House, Antrim, Co. Antrim, Northern Ireland, United Kingdom
| | - Geoff McMullan
- Institute for Global Food Security, School of Biological Sciences, Medical Biology Centre, Queens University Belfast, Belfast, Northern Ireland, United Kingdom
| | - Nigel G. Ternan
- Nutrition Innovation Centre for food and HEalth (NICHE), School of Biomedical Sciences, University of Ulster, Coleraine, Co. Londonderry, Northern Ireland, United Kingdom
- * E-mail:
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404
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Tan JPK, Coady DJ, Sardon H, Yuen A, Gao S, Lim SW, Liang ZC, Tan EW, Venkataraman S, Engler AC, Fevre M, Ono R, Yang YY, Hedrick JL. Broad Spectrum Macromolecular Antimicrobials with Biofilm Disruption Capability and In Vivo Efficacy. Adv Healthc Mater 2017; 6. [PMID: 28504348 DOI: 10.1002/adhm.201601420] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 03/24/2017] [Indexed: 12/28/2022]
Abstract
In this study, antimicrobial polymers are synthesized by the organocatalytic ring-opening polymerization of an eight-membered heterocyclic carbonate monomer that is subsequently quaternized with methyl iodide. These polymers demonstrate activity against clinically relevant Gram-positive Staphylococcus epidermidis and Staphylococcus aureus, Gram-negative Escherichia coli and Pseudomonas aeruginosa, and fungus Candida albicans with fast killing kinetics. Importantly, the polymer efficiently inhibits biofilm growth and lyses existing biofilm, leading to a reduction in biomass and cell viability. In addition, the macromolecular antimicrobial is less likely to induce resistance as it acts via a membrane-lytic mechanism. The polymer is not cytotoxic toward mammalian cells with LD50 of 99.0 ± 11.6 mg kg-1 in mice through i.v. injection. In an S. aureus blood stream infection mouse model, the polymer removes bacteria from the blood more rapidly than the antibiotic Augmentin. At the effective dose, the polymer treatment does not damage liver and kidney tissues or functions. In addition, blood electrolyte balance remains unchanged after the treatment. The low cost of starting materials, ease of synthesis, nontoxicity, broad spectrum activity with fast killing kinetics, and in vivo antimicrobial activity make these macromolecular antimicrobials ideal candidates for prevention of sepsis and treatment of infections.
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Affiliation(s)
- Jeremy P. K. Tan
- Institute of Bioengineering and Nanotechnology; 31 Biopolis Way Singapore 138669 Singapore
| | - Daniel J. Coady
- IBM Almaden Research Center; 650 Harry Road San Jose CA 95120 USA
| | - Haritz Sardon
- POLYMAT; University of the Basque Country UPV/EHU Joxe Mari Korta Center; Avda. Tolosa 72 20018 Donostia-San Sebastián Spain
- Ikerbasque, Basque Foundation for Science; E-48011 Bilbao Spain
| | - Alexander Yuen
- POLYMAT; University of the Basque Country UPV/EHU Joxe Mari Korta Center; Avda. Tolosa 72 20018 Donostia-San Sebastián Spain
| | - Shujun Gao
- Institute of Bioengineering and Nanotechnology; 31 Biopolis Way Singapore 138669 Singapore
| | - Shaun W. Lim
- Institute of Bioengineering and Nanotechnology; 31 Biopolis Way Singapore 138669 Singapore
| | - Zhen Chang Liang
- Institute of Bioengineering and Nanotechnology; 31 Biopolis Way Singapore 138669 Singapore
| | - Eddy W. Tan
- Institute of Bioengineering and Nanotechnology; 31 Biopolis Way Singapore 138669 Singapore
| | - Shrinivas Venkataraman
- Institute of Bioengineering and Nanotechnology; 31 Biopolis Way Singapore 138669 Singapore
| | - Amanda C. Engler
- IBM Almaden Research Center; 650 Harry Road San Jose CA 95120 USA
| | - Mareva Fevre
- IBM Almaden Research Center; 650 Harry Road San Jose CA 95120 USA
| | - Robert Ono
- IBM Almaden Research Center; 650 Harry Road San Jose CA 95120 USA
| | - Yi Yan Yang
- Institute of Bioengineering and Nanotechnology; 31 Biopolis Way Singapore 138669 Singapore
| | - James L. Hedrick
- IBM Almaden Research Center; 650 Harry Road San Jose CA 95120 USA
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405
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Kim TS, Ham SY, Park BB, Byun Y, Park HD. Lauroyl Arginate Ethyl Blocks the Iron Signals Necessary for Pseudomonas aeruginosa Biofilm Development. Front Microbiol 2017; 8:970. [PMID: 28611763 PMCID: PMC5447684 DOI: 10.3389/fmicb.2017.00970] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Accepted: 05/15/2017] [Indexed: 12/02/2022] Open
Abstract
Pseudomonas aeruginosa is a ubiquitous gram-negative bacterium capable of forming a biofilm on living and non-living surfaces, which frequently leads to undesirable consequences. We found that lauroyl arginate ethyl (LAE), a synthetic non-oxidizing biocide, inhibited biofilm formation by P. aeruginosa at a sub-growth inhibitory concentration under both static and flow conditions. A global transcriptome analysis was conducted using a gene chip microarray to identify the genes targeted by LAE. In response to LAE treatment, P. aeruginosa cells up-regulated iron acquisition and signaling genes and down-regulated iron storage genes. LAE demonstrated the capacity to chelate iron in an experiment in which free LAE molecules were measured by increasing the ratio of iron to LAE. Furthermore, compared to untreated cells, P. aeruginosa cells treated with LAE exhibited enhanced twitching motility, a phenotype that is usually evident when the cells are starved for iron. Taken together, these results imply that LAE generated iron-limiting conditions, and in turn, blocked iron signals necessary for P. aeruginosa biofilm development. As destroying or blocking signals leading to biofilm development would be an efficient way to mitigate problematic biofilms, our findings suggest that LAE can aid in reducing P. aeruginosa biofilms for therapeutic and industrial purposes.
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Affiliation(s)
- Taek-Seung Kim
- School of Civil, Environmental and Architectural Engineering, Korea UniversitySeoul, South Korea
| | - So-Young Ham
- School of Civil, Environmental and Architectural Engineering, Korea UniversitySeoul, South Korea
| | - Bernie B Park
- College of Pharmacy, Korea UniversitySejong, South Korea
| | - Youngjoo Byun
- College of Pharmacy, Korea UniversitySejong, South Korea
| | - Hee-Deung Park
- School of Civil, Environmental and Architectural Engineering, Korea UniversitySeoul, South Korea
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406
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Keum H, Kim JY, Yu B, Yu SJ, Kim J, Jeon H, Lee DY, Im SG, Jon S. Prevention of Bacterial Colonization on Catheters by a One-Step Coating Process Involving an Antibiofouling Polymer in Water. ACS APPLIED MATERIALS & INTERFACES 2017; 9:19736-19745. [PMID: 28569502 DOI: 10.1021/acsami.7b06899] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
As reports of multidrug resistant pathogens have increased, patients with implanted medical catheters increasingly need alternative solutions to antibiotic treatments. As most catheter-related infections are directly associated with biofilm formation on the catheter surface, which, once formed, is difficult to eliminate, a promising approach to biofilm prevention involves inhibiting the initial adhesion of bacteria to the surface. In this study, we report an amphiphilic, antifouling polymer, poly(DMA-mPEGMA-AA) that can facilely coat the surfaces of commercially available catheter materials in water and prevent bacterial adhesion to and subsequent colonization of the surface, giving rise to an antibiofilm surface. The antifouling coating layer was formed simply by dipping a model substrate (polystyrene, PET, PDMS, or silicon-based urinary catheter) in water containing poly(DMA-mPEGMA-AA), followed by characterization by X-ray photoelectron spectroscopy (XPS). The antibacterial adhesion properties of the polymer-coated surface were assessed for Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) growth under static (incubation in the presence of a bacterial suspension) and dynamic (bacteria suspended in a solution under flow) conditions. Regardless of the conditions, the polymer-coated surface displayed significantly reduced attachment of the bacteria (antiadhesion effect > ∼8-fold) compared to the bare noncoated substrates. Treatment of the implanted catheters with S. aureus in vivo further confirmed that the polymer-coated silicon urinary catheters could significantly reduce bacterial adhesion and biofilm formation in a bacterial infection animal model. Furthermore, the polymer-coated catheters did not induce hemolysis and were resistant to the adhesion of blood-circulating cells, indicative of high biocompatibility. Collectively, the present amphiphilic antifouling polymer is potentially useful as a coating platform that renders existing medical devices resistant to biofilm formation.
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Affiliation(s)
- Hyeongseop Keum
- KAIST Institute for the BioCentury, Department of Biological Sciences, ‡Graduate School of Medical Science and Engineering, and §KAIST Institute for the NanoCentury, Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST) , 291 Daehak-ro, Daejeon 34141, Republic of Korea
| | - Jin Yong Kim
- KAIST Institute for the BioCentury, Department of Biological Sciences, ‡Graduate School of Medical Science and Engineering, and §KAIST Institute for the NanoCentury, Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST) , 291 Daehak-ro, Daejeon 34141, Republic of Korea
| | - Byeongjun Yu
- KAIST Institute for the BioCentury, Department of Biological Sciences, ‡Graduate School of Medical Science and Engineering, and §KAIST Institute for the NanoCentury, Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST) , 291 Daehak-ro, Daejeon 34141, Republic of Korea
| | - Seung Jung Yu
- KAIST Institute for the BioCentury, Department of Biological Sciences, ‡Graduate School of Medical Science and Engineering, and §KAIST Institute for the NanoCentury, Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST) , 291 Daehak-ro, Daejeon 34141, Republic of Korea
| | - Jinjoo Kim
- KAIST Institute for the BioCentury, Department of Biological Sciences, ‡Graduate School of Medical Science and Engineering, and §KAIST Institute for the NanoCentury, Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST) , 291 Daehak-ro, Daejeon 34141, Republic of Korea
| | - Hyungsu Jeon
- KAIST Institute for the BioCentury, Department of Biological Sciences, ‡Graduate School of Medical Science and Engineering, and §KAIST Institute for the NanoCentury, Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST) , 291 Daehak-ro, Daejeon 34141, Republic of Korea
| | - Dong Yun Lee
- KAIST Institute for the BioCentury, Department of Biological Sciences, ‡Graduate School of Medical Science and Engineering, and §KAIST Institute for the NanoCentury, Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST) , 291 Daehak-ro, Daejeon 34141, Republic of Korea
| | - Sung Gap Im
- KAIST Institute for the BioCentury, Department of Biological Sciences, ‡Graduate School of Medical Science and Engineering, and §KAIST Institute for the NanoCentury, Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST) , 291 Daehak-ro, Daejeon 34141, Republic of Korea
| | - Sangyong Jon
- KAIST Institute for the BioCentury, Department of Biological Sciences, ‡Graduate School of Medical Science and Engineering, and §KAIST Institute for the NanoCentury, Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST) , 291 Daehak-ro, Daejeon 34141, Republic of Korea
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407
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Biofilm is a Major Virulence Determinant in Bacterial Colonization of Chronic Skin Ulcers Independently from the Multidrug Resistant Phenotype. Int J Mol Sci 2017; 18:ijms18051077. [PMID: 28513576 PMCID: PMC5454986 DOI: 10.3390/ijms18051077] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2017] [Revised: 05/06/2017] [Accepted: 05/11/2017] [Indexed: 01/28/2023] Open
Abstract
Bacterial biofilm is a major factor in delayed wound healing and high levels of biofilm production have been repeatedly described in multidrug resistant organisms (MDROs). Nevertheless, a quantitative correlation between biofilm production and the profile of antimicrobial drug resistance in delayed wound healing remains to be determined. Microbial identification, antibiotic susceptibility and biofilm production were assessed in 135 clinical isolates from 87 patients. Gram-negative bacteria were the most represented microorganisms (60.8%) with MDROs accounting for 31.8% of the total isolates. Assessment of biofilm production revealed that 80% of the strains were able to form biofilm. A comparable level of biofilm production was found with both MDRO and not-MDRO with no significant differences between groups. All the methicillin-resistant Staphylococcus aureus (MRSA) and 80% of Pseudomonas aeruginosa MDR strains were found as moderate/high biofilm producers. Conversely, less than 17% of Klebsiella pneumoniae extended-spectrum beta-lactamase (ESBL), Escherichia coli-ESBL and Acinetobacter baumannii were moderate/high biofilm producers. Notably, those strains classified as non-biofilm producers, were always associated with biofilm producer bacteria in polymicrobial colonization. This study shows that biofilm producers were present in all chronic skin ulcers, suggesting that biofilm represents a key virulence determinant in promoting bacterial persistence and chronicity of ulcerative lesions independently from the MDRO phenotype.
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408
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Mycobacterium chimaera infections in post-operative patients exposed to heater-cooler devices: An overview. ACTA ACUST UNITED AC 2017; 43:107-113. [PMID: 29770074 DOI: 10.14745/ccdr.v43i05a05] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
A multi-country outbreak of Mycobacterium chimaera infection associated with contaminated heater-cooler devices (HCDs) has been reported, with more than 70 cases in Europe and the United States and two cases in Canada to date. The epidemiological and microbiological characteristics of this outbreak provide evidence for common-source transmission of M. chimaera from the exhaust air of intrinsically contaminated HCDs to patients during cardiac surgery. To date, all reported cases have been associated with Stöckert 3T HCDs manufactured at one plant by LivaNova prior to September 2014. Implantation of prosthetic material increases the risk of infection. Infections usually present as prosthetic valve endocarditis, vascular graft infection or disseminated infection. Reported mortality rates have varied, but were often over 40%. Several measures are recommended to facilitate case-finding and mitigate risk of exposure. The feasibility of some risk mitigation measures and their effectiveness in reducing the risk of exposure are yet to be determined. Until HCDs are redesigned in a manner that prevents water contamination and aerosolization, separating the HCD exhaust air from the operating room air during surgery may be the most effective risk mitigation strategy. However, possible unintended consequences of this approach should be considered. This overview summarizes findings from peer-reviewed and other relevant national documents on key features of the outbreak, including the source, identified risk factors for infection, signs and symptoms of infection, burden of disease, risk mitigation measures, management challenges and knowledge gaps.
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409
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Francolini I, Vuotto C, Piozzi A, Donelli G. Antifouling and antimicrobial biomaterials: an overview. APMIS 2017; 125:392-417. [PMID: 28407425 DOI: 10.1111/apm.12675] [Citation(s) in RCA: 161] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2016] [Accepted: 01/14/2017] [Indexed: 12/12/2022]
Abstract
The use of implantable medical devices is a common and indispensable part of medical care for both diagnostic and therapeutic purposes. However, as side effect, the implant of medical devices quite often leads to the occurrence of difficult-to-treat infections, as a consequence of the colonization of their abiotic surfaces by biofilm-growing microorganisms increasingly resistant to antimicrobial therapies. A promising strategy to combat device-related infections is based on anti-infective biomaterials that either repel microbes, so they cannot attach to the device surfaces, or kill them in the surrounding areas. In general, such biomaterials are characterized by antifouling coatings, exhibiting low adhesion or even repellent properties towards microorganisms, or antimicrobial coatings, able to kill microbes approaching the surface. In this light, the present overview will address the development in the last two decades of antifouling and antimicrobial biomaterials designed to potentially limit the initial stages of microbial adhesion, as well as the microbial growth and biofilm formation on medical device surfaces.
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Affiliation(s)
| | - Claudia Vuotto
- Microbial Biofilm Laboratory, IRCCS Fondazione Santa Lucia, Rome
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410
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Yadav MK, Chae SW, Go YY, Im GJ, Song JJ. In vitro Multi-Species Biofilms of Methicillin-Resistant Staphylococcus aureus and Pseudomonas aeruginosa and Their Host Interaction during In vivo Colonization of an Otitis Media Rat Model. Front Cell Infect Microbiol 2017; 7:125. [PMID: 28459043 PMCID: PMC5394157 DOI: 10.3389/fcimb.2017.00125] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Accepted: 03/27/2017] [Indexed: 01/30/2023] Open
Abstract
Staphylococcus aureus (SA) and Pseudomonas aeruginosa (PA) are known to cause biofilm-related infections. MRSA and PA have been frequently isolated from chronically infected wounds, cystic fibrosis, chronic suppurative otitis media (CSOM), and from indwelling medical devices, and these bacteria co-exist; however, their interaction with each-other or with the host is not well known. In this study, we investigated MRSA and PA multi-species biofilm communities in vitro and their interaction with the host during in vivo colonization using an OM rat-model. In-vitro biofilm formation and in-vivo colonization were studied using CV-microtiter plate assay and OM rat-model respectively. The biofilms were viewed under scanning electron microscope and bacteria were enumerated using cfu counts. The differential gene expressions of rat mucosa colonized with single or multi-species of MRSA or PA were studied using RNA-sequencing of total transcriptome. In multi-species in-vitro biofilms PA partially inhibited SA growth. However, no significant inhibition of MRSA was detected during in-vivo colonization of multi-species in rat bullae. A total of 1,797 genes were significantly (p < 0.05) differentially expressed in MRSA or PA or MRSA + PA colonized rat middle ear mucosa with respect to the control. The poly-microbial colonization of MRSA and PA induced the differential expression of a significant number of genes that are involved in immune response, inflammation, signaling, development, and defense; these were not expressed with single species colonization by either MRSA or PA. Genes involved in defense, immune response, inflammatory response, and developmental process were exclusively up-regulated, and genes that are involved in nervous system signaling, development and transmission, regulation of cell growth and development, anatomical and system development, and cell differentiation were down-regulated after multi-species inoculation. These results indicate that poly-microbial colonization induces a host response that is different from that induced by single species infection.
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Affiliation(s)
- Mukesh K Yadav
- Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of MedicineSeoul, South Korea.,Institute for Medical Device Clinical Trials, Korea University College of MedicineSeoul, South Korea
| | - Sung-Won Chae
- Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of MedicineSeoul, South Korea
| | - Yoon Young Go
- Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of MedicineSeoul, South Korea
| | - Gi Jung Im
- Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of MedicineSeoul, South Korea
| | - Jae-Jun Song
- Department of Otorhinolaryngology-Head and Neck Surgery, Korea University College of MedicineSeoul, South Korea
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411
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Kratochvil MJ, Yang T, Blackwell HE, Lynn DM. Nonwoven Polymer Nanofiber Coatings That Inhibit Quorum Sensing in Staphylococcus aureus: Toward New Nonbactericidal Approaches to Infection Control. ACS Infect Dis 2017; 3:271-280. [PMID: 28118541 PMCID: PMC5392134 DOI: 10.1021/acsinfecdis.6b00173] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
We report the fabrication and biological evaluation of nonwoven polymer nanofiber coatings that inhibit quorum sensing (QS) and virulence in the human pathogen Staphylococcus aureus. Our results demonstrate that macrocyclic peptide 1, a potent and synthetic nonbactericidal quorum sensing inhibitor (QSI) in S. aureus, can be loaded into degradable polymer nanofibers by electrospinning and that this approach can deposit QSI-loaded nanofiber coatings onto model nonwoven mesh substrates. The QSI was released over ∼3 weeks when these materials were incubated in physiological buffer, retained its biological activity, and strongly inhibited agr-based QS in a GFP reporter strain of S. aureus for at least 14 days without promoting cell death. These materials also inhibited production of hemolysins, a QS-controlled virulence phenotype, and reduced the lysis of erythrocytes when placed in contact with wild-type S. aureus growing on surfaces. This approach is modular and can be used with many different polymers, active agents, and processing parameters to fabricate nanofiber coatings on surfaces important in healthcare contexts. S. aureus is one of the most common causative agents of bacterial infections in humans, and strains of this pathogen have developed significant resistance to conventional antibiotics. The QSI-based strategies reported here thus provide springboards for the development of new anti-infective materials and novel treatment strategies that target virulence as opposed to growth in S. aureus. This approach also provides porous scaffolds for cell culture that could prove useful in future studies on the influence of QS modulation on the development and structure of bacterial communities.
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Affiliation(s)
- Michael J. Kratochvil
- Department of Chemistry, 1101 University Avenue, University of Wisconsin–Madison, Madison, Wisconsin 53706
| | - Tian Yang
- Department of Chemistry, 1101 University Avenue, University of Wisconsin–Madison, Madison, Wisconsin 53706
| | - Helen E. Blackwell
- Department of Chemistry, 1101 University Avenue, University of Wisconsin–Madison, Madison, Wisconsin 53706
| | - David M. Lynn
- Department of Chemistry, 1101 University Avenue, University of Wisconsin–Madison, Madison, Wisconsin 53706
- Department of Chemical and Biological Engineering, 1415 Engineering Drive, University of Wisconsin–Madison, Madison, Wisconsin 53706
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412
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Bandeira M, Borges V, Gomes JP, Duarte A, Jordao L. Insights on Klebsiella pneumoniae Biofilms Assembled on Different Surfaces Using Phenotypic and Genotypic Approaches. Microorganisms 2017; 5:microorganisms5020016. [PMID: 28368366 PMCID: PMC5488087 DOI: 10.3390/microorganisms5020016] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Revised: 03/06/2017] [Accepted: 03/29/2017] [Indexed: 12/26/2022] Open
Abstract
Klebsiella pneumoniae is a prominent etiological agent of healthcare associated infections (HAIs). In this context, multidrug-resistant and biofilm-producing bacteria are of special public health concern due to the difficulties associated with treatment of human infections and eradication from hospital environments. Here, in order to study the impact of medical devices-associated materials on the biofilm dynamics, we performed biofilm phenotypic analyses through a classic and a new scanning electron microscopy (SEM) technique for three multidrug-resistant K. pneumoniae isolates growing on polystyrene and silicone. We also applied whole-genome sequencing (WGS) to search for genetic clues underlying biofilm phenotypic differences. We found major differences in the extracellular polymeric substances (EPS) content among the three strains, which were further corroborated by in-depth EPS composition analysis. WGS analysis revealed a high nucleotide similarity within the core-genome, but relevant differences in the accessory genome that may account for the detected biofilm phenotypic dissimilarities, such as genes already associated with biofilm formation in other pathogenic bacteria (e.g., genes coding haemogglutinins and haemolysins). These data reinforce that the research efforts to defeat bacterial biofilms should take into account that their dynamics may be contingent on the medical devices-associated materials.
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Affiliation(s)
- Maria Bandeira
- Instituto Nacional de Saúde Dr Ricardo Jorge, Departamento de Saúde Ambiental, Unidade de Investigação e Desenvolvimento-Lisboa, Avenida Padre Cruz, 1649-016 Lisboa, Portugal.
- Universidade de Lisboa, Instituto Superior Técnico, Departamento de Engenharia Química, Avenida Rovisco Pais, 1049-001 Lisboa, Portugal.
| | - Vítor Borges
- Instituto Nacional de Saúde Dr Ricardo Jorge, Departamento de Doenças Infeciosas, Núcleo de Bioinformática, Avenida Padre Cruz, 1649-016 Lisboa, Portugal.
| | - João P Gomes
- Instituto Nacional de Saúde Dr Ricardo Jorge, Departamento de Doenças Infeciosas, Núcleo de Bioinformática, Avenida Padre Cruz, 1649-016 Lisboa, Portugal.
| | - Aida Duarte
- Universidade de Lisboa, Faculdade de Farmácia, Av Prof Gama Pinto, 1649-003 Lisboa, Portugal.
| | - Luisa Jordao
- Instituto Nacional de Saúde Dr Ricardo Jorge, Departamento de Saúde Ambiental, Unidade de Investigação e Desenvolvimento-Lisboa, Avenida Padre Cruz, 1649-016 Lisboa, Portugal.
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413
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Abstract
Biofilms are a major aetiological factor in many infections. Bacteria growing within a biofilm are extremely resilient to standard antimicrobials; biofilm-associated infections are thus challenging to treat. Understanding how and why biofilms form can improve prevention and management of biofilm infections.
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Affiliation(s)
- Carlene Rowson
- Specialist Trainee in Infectious Diseases and Medical Microbiology, Departments of Infectious Diseases and Medical Microbiology, Sheffield Teaching Hospital, Sheffield S5 7AU
| | - Robert Townsend
- Consultant Medical Microbiologist at Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield, Honorary Senior Clinical Lecturer, University of Sheffield and Honorary Clinical Fellow at Sheffield Hallam University, Sheffield
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414
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Antimicrobial Dendrimeric Peptides: Structure, Activity and New Therapeutic Applications. Int J Mol Sci 2017; 18:ijms18030542. [PMID: 28273806 PMCID: PMC5372558 DOI: 10.3390/ijms18030542] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2017] [Revised: 02/15/2017] [Accepted: 02/23/2017] [Indexed: 01/09/2023] Open
Abstract
Microbial resistance to conventional antibiotics is one of the most outstanding medical and scientific challenges of our times. Despite the recognised need for new anti-infective agents, however, very few new drugs have been brought to the market and to the clinic in the last three decades. This review highlights the properties of a new class of antibiotics, namely dendrimeric peptides. These intriguing novel compounds, generally made of multiple peptidic sequences linked to an inner branched core, display an array of antibacterial, antiviral and antifungal activities, usually coupled to low haemolytic activity. In addition, several peptides synthesized in oligobranched form proved to be promising tools for the selective treatment of cancer cells.
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415
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Manner S, Goeres DM, Skogman M, Vuorela P, Fallarero A. Prevention of Staphylococcus aureus biofilm formation by antibiotics in 96-Microtiter Well Plates and Drip Flow Reactors: critical factors influencing outcomes. Sci Rep 2017; 7:43854. [PMID: 28252025 PMCID: PMC5333151 DOI: 10.1038/srep43854] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2016] [Accepted: 01/31/2017] [Indexed: 12/27/2022] Open
Abstract
Biofilm formation leads to the failure of antimicrobial therapy. Thus, biofilm prevention is a desirable goal of antimicrobial research. In this study, the efficacy of antibiotics (doxycycline, oxacillin and rifampicin) in preventing Staphylococcus aureus biofilms was investigated using Microtiter Well Plates (MWP) and Drip Flow Reactors (DFR), two models characterized by the absence and the presence of a continuous flow of nutrients, respectively. Planktonic culture of S. aureus was exposed to antibiotics for one hour followed by 24 hours incubation with fresh nutrients in MWP or continuous flow of nutrients in DFR. The DFR grown biofilms were significantly more tolerant to the antibiotics than those grown in MWP without the continuous flow. The differences in log reductions (LR) between the two models could not be attributed to differences in the cell density, the planktonic inoculum concentration or the surface-area-to-volume ratios. However, eliminating the flow in the DFR significantly restored the antibiotic susceptibility. These findings demonstrate the importance of considering differences between experimental conditions in different model systems, particularly the flow of nutrients, when performing anti-biofilm efficacy evaluations. Biofilm antibiotic efficacy studies should be assessed using various models and more importantly, in a model mimicking conditions of its clinical application.
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Affiliation(s)
- Suvi Manner
- Pharmaceutical Sciences Laboratory, Faculty of Science and Engineering, Abo Akademi University, BioCity, Artillerigatan 6A, FI-20520, Turku, Finland
| | - Darla M Goeres
- Center for Biofilm Engineering, Montana State University, Bozeman, MT 59717, USA
| | - Malena Skogman
- Pharmaceutical Design and Discovery (PharmDD), Pharmaceutical Biology, Division of Pharmaceutical Biosciences, Faculty of Pharmacy, University of Helsinki, Viikinkaari 5E, P.O. Box 56, FI-00014 University of Helsinki, Finland
| | - Pia Vuorela
- Pharmaceutical Design and Discovery (PharmDD), Pharmaceutical Biology, Division of Pharmaceutical Biosciences, Faculty of Pharmacy, University of Helsinki, Viikinkaari 5E, P.O. Box 56, FI-00014 University of Helsinki, Finland
| | - Adyary Fallarero
- Pharmaceutical Design and Discovery (PharmDD), Pharmaceutical Biology, Division of Pharmaceutical Biosciences, Faculty of Pharmacy, University of Helsinki, Viikinkaari 5E, P.O. Box 56, FI-00014 University of Helsinki, Finland
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416
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Tripathi A, Melo JS. Development of Nano-Antimicrobial Biomaterials for Biomedical Applications. ADVANCES IN BIOMATERIALS FOR BIOMEDICAL APPLICATIONS 2017; 66. [PMCID: PMC7122509 DOI: 10.1007/978-981-10-3328-5_12] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Around the globe, there is a great concern about controlling growth of pathogenic microorganisms for the prevention of infectious diseases. Moreover, the greater incidences of cross contamination and overuse of drugs has contributed towards the development of drug resistant microbial strains making conditions even worse. Hospital acquired infections pose one of the leading complications associated with implantation of any biomaterial after surgery and critical care. In this regard, developing non-conventional antimicrobial agents which would prevent the aforementioned causes is under the quest. The rapid development in nanoscience and nanotechnology has shown promising potential for developing novel biocidal agents that would integrate with a biomaterial to prevent bacterial colonization and biofilm formation. Metals with inherent antimicrobial properties such as silver, copper, zinc at nano scale constitute a special class of antimicrobials which have broad spectrum antimicrobial nature and pose minimum toxicity to humans. Hence, novel biomaterials that inhibit microbial growth would be of great significance to eliminate medical device/instruments associated infections. This chapter comprises the state-of-art advancements in the development of nano-antimicrobial biomaterials for biomedical applications. Several strategies have been targeted to satisfy few important concern such as enhanced long term antimicrobial activity and stability, minimize leaching of antimicrobial material and promote reuse. The proposed strategies to develop new hybrid antimicrobial biomaterials would offer a potent antibacterial solution in healthcare sector such as wound healing applications, tissue scaffolds, medical implants, surgical devices and instruments.
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Affiliation(s)
- Anuj Tripathi
- Nuclear Agriculture & Biotechnology Div, Bhabha Atomic Research Centre, Mumbai, Maharashtra India
| | - Jose Savio Melo
- Nuclear Agriculture & Biotechnology Div, Bhabha Atomic Research Centre, Mumbai, Maharashtra India
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417
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Percival SL, Salisbury AM. The Efficacy of Tetrasodium EDTA on Biofilms. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 1057:101-110. [PMID: 29280095 DOI: 10.1007/5584_2017_134] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The aetiology of delayed wound healing characteristic of a chronic wound is relatively unknown but is thought to be due to a combination of the patient's underlying pathophysiology and external factors including infection and biofilm formation. The invasion of the wound by the hosts' resident microbiome and exogenous microorganisms can lead to biofilm formation. Biofilms have increased tolerance to antimicrobial interventions and constitute a concern to chronic wound healing. Consequently, anti-biofilm technologies with proven efficacy in areas outside of wound care need evaluation to determine whether their efficacy could be relevant to the control of biofilms in wounds. The aim of this study was to assess the anti-biofilm capabilities of tetrasodium EDTA (t-EDTA) as a stand-alone liquid and when incorporated in low concentrations into wound dressing prototypes. Results demonstrated that a low concentration of t-EDTA (4%) solution was able to kill Staphylococcus aureus, methicillin-resistant S. aureus (MRSA), S. epidermidis, Pseudomonas aeruginosa and Enterococcus faecalis within in vitro biofilms after a 24-h contact time. The incorporation of low levels of t-EDTA into prototype fibrous wound dressings resulted in a 3-log reduction of bacteria demonstrating its microbicidal ability. Furthermore, hydrogels incorporating only a 0.2% concentration of t-EDTA (at preservative levels) caused a small reduction in biofilm. In conclusion, these studies show that t-EDTA as a stand-alone agent is an effective anti-biofilm agent in vitro. We have demonstrated that t-EDTA is compatible with numerous wound dressing platforms. EDTA could provide an essential tool to manage biofilm-related infections and should be considered as an anti-biofilm agent alone or in combination with other antimicrobials or technologies for increased antimicrobial performance in recalcitrant wounds.
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Affiliation(s)
- S L Percival
- Centre of Excellence in Biofilm Science and Technologies (CEBST), 5D Health Protection Group Ltd, Liverpool Bio-innovation Hub, Liverpool, UK.
| | - A-M Salisbury
- Centre of Excellence in Biofilm Science and Technologies (CEBST), 5D Health Protection Group Ltd, Liverpool Bio-innovation Hub, Liverpool, UK
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418
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Neoh KG, Li M, Kang ET, Chiong E, Tambyah PA. Surface modification strategies for combating catheter-related complications: recent advances and challenges. J Mater Chem B 2017; 5:2045-2067. [DOI: 10.1039/c6tb03280j] [Citation(s) in RCA: 86] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
This review summarizes the progress made in addressing bacterial colonization and other surface-related complications arising from catheter use.
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Affiliation(s)
- Koon Gee Neoh
- Department of Chemical and Biomolecular Engineering
- National University of Singapore
- Singapore 119077
| | - Min Li
- Department of Chemical and Biomolecular Engineering
- National University of Singapore
- Singapore 119077
| | - En-Tang Kang
- Department of Chemical and Biomolecular Engineering
- National University of Singapore
- Singapore 119077
| | - Edmund Chiong
- Department of Surgery
- National University of Singapore
- Singapore 119077
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419
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Di Domenico EG, Toma L, Provot C, Ascenzioni F, Sperduti I, Prignano G, Gallo MT, Pimpinelli F, Bordignon V, Bernardi T, Ensoli F. Development of an in vitro Assay, Based on the BioFilm Ring Test ®, for Rapid Profiling of Biofilm-Growing Bacteria. Front Microbiol 2016; 7:1429. [PMID: 27708625 PMCID: PMC5030256 DOI: 10.3389/fmicb.2016.01429] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Accepted: 08/29/2016] [Indexed: 01/05/2023] Open
Abstract
Microbial biofilm represents a major virulence factor associated with chronic and recurrent infections. Pathogenic bacteria embedded in biofilms are highly resistant to environmental and chemical agents, including antibiotics and therefore difficult to eradicate. Thus, reliable tests to assess biofilm formation by bacterial strains as well as the impact of chemicals or antibiotics on biofilm formation represent desirable tools for a most effective therapeutic management and microbiological risk control. Current methods to evaluate biofilm formation are usually time-consuming, costly, and hardly applicable in the clinical setting. The aim of the present study was to develop and assess a simple and reliable in vitro procedure for the characterization of biofilm-producing bacterial strains for future clinical applications based on the BioFilm Ring Test® (BRT) technology. The procedure developed for clinical testing (cBRT) can provide an accurate and timely (5 h) measurement of biofilm formation for the most common pathogenic bacteria seen in clinical practice. The results gathered by the cBRT assay were in agreement with the traditional crystal violet (CV) staining test, according to the κ coefficient test (κ = 0.623). However, the cBRT assay showed higher levels of specificity (92.2%) and accuracy (88.1%) as compared to CV. The results indicate that this procedure offers an easy, rapid and robust assay to test microbial biofilm and a promising tool for clinical microbiology.
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Affiliation(s)
- Enea G Di Domenico
- Clinical Pathology and Microbiology Department, San Gallicano Institute, Istituti di Ricovero e Cura a Carattere Scientifico Rome, Italy
| | - Luigi Toma
- Infectious Disease Consultant, San Gallicano Institute, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Rome, Italy
| | - Christian Provot
- BioFilm Control, Biopole Clermont Limagne Saint Beauzire, France
| | - Fiorentina Ascenzioni
- Department of Biology and Biotechnology C. Darwin, Sapienza University of Rome Rome, Italy
| | - Isabella Sperduti
- Biostatistics, San Gallicano Institute, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Rome, Italy
| | - Grazia Prignano
- Clinical Pathology and Microbiology Department, San Gallicano Institute, Istituti di Ricovero e Cura a Carattere Scientifico Rome, Italy
| | - Maria T Gallo
- Clinical Pathology and Microbiology Department, San Gallicano Institute, Istituti di Ricovero e Cura a Carattere Scientifico Rome, Italy
| | - Fulvia Pimpinelli
- Clinical Pathology and Microbiology Department, San Gallicano Institute, Istituti di Ricovero e Cura a Carattere Scientifico Rome, Italy
| | - Valentina Bordignon
- Clinical Pathology and Microbiology Department, San Gallicano Institute, Istituti di Ricovero e Cura a Carattere Scientifico Rome, Italy
| | - Thierry Bernardi
- BioFilm Control, Biopole Clermont Limagne Saint Beauzire, France
| | - Fabrizio Ensoli
- Clinical Pathology and Microbiology Department, San Gallicano Institute, Istituti di Ricovero e Cura a Carattere Scientifico Rome, Italy
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420
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Abstract
ABSTRACT
The immunocompromised host is a particularly vulnerable population in whom routine and unusual infections can easily and frequently occur. Prosthetic devices are commonly used in these patients and the infections associated with those devices present a number of challenges for both the microbiologist and the clinician. Biofilms play a major role in device-related infections, which may contribute to failed attempts to recover organisms from routine culture methods. Moreover, device-related microorganisms can be difficult to eradicate by antibiotic therapy alone. Changes in clinical practice and advances in laboratory diagnostics have provided significant improvements in the detection and accurate diagnosis of device-related infections. Disruption of the bacterial biofilm plays an essential role in recovering the causative agent in culture. Various culture and nucleic acid amplification techniques are more accurate to guide directed treatment regimens. This chapter reviews the performance characteristics of currently available diagnostic assays and summarizes published guidelines, where available, for addressing suspected infected prosthetic devices.
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421
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Michiels JE, Van den Bergh B, Verstraeten N, Fauvart M, Michiels J. In Vitro Emergence of High Persistence upon Periodic Aminoglycoside Challenge in the ESKAPE Pathogens. Antimicrob Agents Chemother 2016; 60:4630-7. [PMID: 27185802 PMCID: PMC4958152 DOI: 10.1128/aac.00757-16] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Accepted: 05/10/2016] [Indexed: 12/31/2022] Open
Abstract
Health care-associated infections present a major threat to modern medical care. Six worrisome nosocomial pathogens-Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp.-are collectively referred to as the "ESKAPE bugs." They are notorious for extensive multidrug resistance, yet persistence, or the phenotypic tolerance displayed by a variant subpopulation, remains underappreciated in these pathogens. Importantly, persistence can prevent eradication of antibiotic-sensitive bacterial populations and is thought to act as a catalyst for the development of genetic resistance. Concentration- and time-dependent aminoglycoside killing experiments were used to investigate persistence in the ESKAPE pathogens. Additionally, a recently developed method for the experimental evolution of persistence was employed to investigate adaptation to high-dose, extended-interval aminoglycoside therapy in vitro We show that ESKAPE pathogens exhibit biphasic killing kinetics, indicative of persister formation. In vitro cycling between aminoglycoside killing and persister cell regrowth, evocative of clinical high-dose extended-interval therapy, caused a 37- to 213-fold increase in persistence without the emergence of resistance. Increased persistence also manifested in biofilms and provided cross-tolerance to different clinically important antibiotics. Together, our results highlight a possible drawback of intermittent, high-dose antibiotic therapy and suggest that clinical diagnostics might benefit from taking into account persistence.
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Affiliation(s)
| | | | | | - Maarten Fauvart
- Centre of Microbial and Plant Genetics, KU Leuven, Leuven, Belgium Smart Systems and Emerging Technologies Unit, Department of Life Science Technologies, imec, Leuven, Belgium
| | - Jan Michiels
- Centre of Microbial and Plant Genetics, KU Leuven, Leuven, Belgium
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422
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Jain AL, Harding CM, Assani K, Shrestha CL, Haga M, Leber A, Munson RS, Kopp BT. Characteristics of invasive Acinetobacter species isolates recovered in a pediatric academic center. BMC Infect Dis 2016; 16:346. [PMID: 27449800 PMCID: PMC4957376 DOI: 10.1186/s12879-016-1678-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Accepted: 06/14/2016] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Acinetobacter species are associated with increasing mortality due to emerging drug-resistance. Pediatric Acinetobacter infections are largely undefined in developed countries and clinical laboratory identification methods do not reliably differentiate between members of the Acinetobacter calcoaceticus-baumannii complex, leading to improper identification. Therefore we aimed to determine risk factors for invasive Acinetobacter infections within an academic, pediatric setting as well as defining microbiologic characteristics of predominant strains. METHODS Twenty-four invasive Acinetobacter isolates were collected from 2009-2013. Comparative sequence analysis of the rpoB gene was performed coupled with phenotypic characterization of antibiotic resistance, motility, biofilm production and clinical correlation. RESULTS Affected patients had a median age of 3.5 years, and 71 % had a central catheter infection source. rpoB gene sequencing revealed a predominance of A. pittii (45.8 %) and A. baumannii (33.3 %) strains. There was increasing incidence of A. pittii over the study. Two fatalities occurred in the A. pittii group. Seventeen percent of isolates were multi-drug resistant. A pittii and A. baumannii strains were similar in motility, but A pittii strains had significantly more biofilm production (P value = 0.018). CONCLUSIONS A. pittii was the most isolated species highlighting the need for proper species identification. The isolated strains had limited acute mortality in children, but the occurrence of more multi-drug resistant strains in the future is a distinct possibility, justifying continued research and accurate species identification.
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Affiliation(s)
- Avish L Jain
- Center for Microbial Pathogenesis, The Research Institute at Nationwide Children's Hospital, Columbus, OH, USA
| | - Christian M Harding
- Center for Microbial Pathogenesis, The Research Institute at Nationwide Children's Hospital, Columbus, OH, USA
- Biomedical Sciences Graduate Program, College of Medicine, The Ohio State University, Columbus, OH, USA
| | - Kaivon Assani
- Center for Microbial Pathogenesis, The Research Institute at Nationwide Children's Hospital, Columbus, OH, USA
| | - Chandra L Shrestha
- Center for Microbial Pathogenesis, The Research Institute at Nationwide Children's Hospital, Columbus, OH, USA
| | - Mercedees Haga
- Center for Microbial Pathogenesis, The Research Institute at Nationwide Children's Hospital, Columbus, OH, USA
| | - Amy Leber
- Department of Laboratory Medicine, Nationwide Children's Hospital, Columbus, OH, USA
| | - Robert S Munson
- Center for Microbial Pathogenesis, The Research Institute at Nationwide Children's Hospital, Columbus, OH, USA
| | - Benjamin T Kopp
- Center for Microbial Pathogenesis, The Research Institute at Nationwide Children's Hospital, Columbus, OH, USA.
- Nationwide Children's Hospital, Section of Pulmonary Medicine, 700 Children's Drive, Columbus, OH, 43205, USA.
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423
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Polymeric prodrug-functionalized polypropylene films for sustained release of salicylic acid. Int J Pharm 2016; 511:579-585. [PMID: 27452418 DOI: 10.1016/j.ijpharm.2016.07.044] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Revised: 07/19/2016] [Accepted: 07/20/2016] [Indexed: 01/30/2023]
Abstract
Medical devices decorated with salicylic acid-based polymer chains (polymeric prodrug) that slowly release this anti-inflammatory and anti-biofilm drug at the implantation site were designed. A "grafting from" method was implemented to directly grow chains of a polymerizable derivative of salicylic acid (2-methacryloyloxy-benzoic acid, 2MBA) onto polypropylene (PP). PP was modified both at bulk and on the surface with poly(2MBA) by means of an oxidative pre-irradiation method ((60)Co source), in order to obtain a grafted polymer in which salicylic acid units were linked by means of labile ester bonds. The grafting percent depended on absorbed dose, reaction time, temperature and monomer concentration. The functionalized films were analyzed regarding structure (FTIR-ATR, SEM-EDX, fluorescence microscopy), temperature stability (TGA), interaction with aqueous medium (water contact angle and swelling), pH-responsive release and cytocompatibility (fibroblasts). In the obtained poly(2MBA)-grafted biomaterial, poly(2MBA) behaved as a polymeric prodrug that regulates salicylic acid release once in contact with aqueous medium, showing pH-dependent release rate.
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424
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França A, Pier GB, Vilanova M, Cerca N. Transcriptomic Analysis of Staphylococcus epidermidis Biofilm-Released Cells upon Interaction with Human Blood Circulating Immune Cells and Soluble Factors. Front Microbiol 2016; 7:1143. [PMID: 27493645 PMCID: PMC4955375 DOI: 10.3389/fmicb.2016.01143] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2016] [Accepted: 07/07/2016] [Indexed: 12/27/2022] Open
Affiliation(s)
- Angela França
- Laboratory of Research in Biofilms Rosário Oliveira, Centre of Biological Engineering, University of Minho Braga, Portugal
| | - Gerald B Pier
- Division of Infectious Diseases, Department of Medicine, Brigham and Women's Hospital/Harvard Medical School Boston, MA, USA
| | - Manuel Vilanova
- Instituto de Ciências Biomédicas de Abel Salazar, Universidade do PortoPorto, Portugal; Instituto de Investigação e Inovação em Saúde, Universidade do PortoPorto, Portugal; Instituto de Biologia Molecular e Celular, Universidade do PortoPorto, Portugal
| | - Nuno Cerca
- Laboratory of Research in Biofilms Rosário Oliveira, Centre of Biological Engineering, University of Minho Braga, Portugal
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425
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Zhang Z, Christopher G. Effect of Particulate Contaminants on the Development of Biofilms at Air/Water Interfaces. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2016; 32:2724-30. [PMID: 26943272 DOI: 10.1021/acs.langmuir.6b00143] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The development of biofilms at air/water or oil/water interfaces has important ramifications on several applications, but it has received less attention than biofilm formation on solid surfaces. A key difference between the growth of biofilms on solid surfaces versus liquid interfaces is the range of complicated boundary conditions the liquid interface can create that may affect bacteria, as they adsorb onto and grow on the interface. This situation is exacerbated by the existence of complex interfaces in which interfacially adsorbed components can even more greatly affect interfacial boundary conditions. In this work, we present evidence as to how particle-laden interfaces impact biofilm growth at an air/water interface. We find that particles can enhance the rate of growth and final strength of biofilms at liquid interfaces by providing sites of increased adhesive strength for bacteria. The increased adhesion stems from creating localized areas of hydrophobicity that protrude in the water phase and provide sites where bacteria preferentially adhere. This mechanism is found to be primarily controlled by particle composition, with particle size providing a secondary effect. This increased adhesion through interfacial conditions creates biofilms with properties similar to those observed when adhesion is increased through biological means. Because of the generally understood ubiquity of increased bacteria attachment to hydrophobic surfaces, this result has general applicability to pellicle formation for many pellicle-forming bacteria.
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Affiliation(s)
- Zhenhuan Zhang
- Department of Mechanical Engineering, Texas Tech University , Lubbock, Texas 79409-1035, United States
| | - Gordon Christopher
- Department of Mechanical Engineering, Texas Tech University , Lubbock, Texas 79409-1035, United States
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426
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Chauhan A, Ghigo JM, Beloin C. Study of in vivo catheter biofilm infections using pediatric central venous catheter implanted in rat. Nat Protoc 2016; 11:525-41. [DOI: 10.1038/nprot.2016.033] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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427
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Parrilli E, Ricciardelli A, Casillo A, Sannino F, Papa R, Tilotta M, Artini M, Selan L, Corsaro MM, Tutino ML. Large-scale biofilm cultivation of Antarctic bacterium Pseudoalteromonas haloplanktis TAC125 for physiologic studies and drug discovery. Extremophiles 2016; 20:227-34. [PMID: 26847199 DOI: 10.1007/s00792-016-0813-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Accepted: 01/20/2016] [Indexed: 10/22/2022]
Abstract
Microbial biofilms are mainly studied due to detrimental effects on human health but they are also well established in industrial biotechnology for the production of chemicals. Moreover, biofilm can be considered as a source of novel drugs since the conditions prevailing within biofilm can allow the production of specific metabolites. Antarctic bacterium Pseudoalteromonas haloplanktis TAC125 when grown in biofilm condition produces an anti-biofilm molecule able to inhibit the biofilm of the opportunistic pathogen Staphylococcus epidermidis. In this paper we set up a P. haloplanktis TAC125 biofilm cultivation methodology in automatic bioreactor. The biofilm cultivation was designated to obtain two goals: (1) the scale up of cell-free supernatant production in an amount necessary for the anti-biofilm molecule/s purification; (2) the recovery of P. haloplanktis TAC125 cells grown in biofilm for physiological studies. We set up a fluidized-bed reactor fermentation in which floating polystyrene supports were homogeneously mixed, exposing an optimal air-liquid interface to let bacterium biofilm formation. The proposed methodology allowed a large-scale production of anti-biofilm molecule and paved the way to study differences between P. haloplanktis TAC125 cells grown in biofilm and in planktonic conditions. In particular, the modifications occurring in the lipopolysaccharide of cells grown in biofilm were investigated.
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Affiliation(s)
- Ermenegilda Parrilli
- Department of Chemical Sciences, Federico II University, Complesso Universitario Monte Sant'Angelo, Via Cintia 4, 80126, Naples, Italy.
| | - Annarita Ricciardelli
- Department of Chemical Sciences, Federico II University, Complesso Universitario Monte Sant'Angelo, Via Cintia 4, 80126, Naples, Italy
| | - Angela Casillo
- Department of Chemical Sciences, Federico II University, Complesso Universitario Monte Sant'Angelo, Via Cintia 4, 80126, Naples, Italy
| | - Filomena Sannino
- Department of Chemical Sciences, Federico II University, Complesso Universitario Monte Sant'Angelo, Via Cintia 4, 80126, Naples, Italy
| | - Rosanna Papa
- Department of Public Health and Infectious Diseases, Sapienza University, Piazzale Aldo Moro 5, 00185, Rome, Italy
| | - Marco Tilotta
- Department of Public Health and Infectious Diseases, Sapienza University, Piazzale Aldo Moro 5, 00185, Rome, Italy
| | - Marco Artini
- Department of Public Health and Infectious Diseases, Sapienza University, Piazzale Aldo Moro 5, 00185, Rome, Italy
| | - Laura Selan
- Department of Public Health and Infectious Diseases, Sapienza University, Piazzale Aldo Moro 5, 00185, Rome, Italy
| | - Maria Michela Corsaro
- Department of Chemical Sciences, Federico II University, Complesso Universitario Monte Sant'Angelo, Via Cintia 4, 80126, Naples, Italy
| | - Maria Luisa Tutino
- Department of Chemical Sciences, Federico II University, Complesso Universitario Monte Sant'Angelo, Via Cintia 4, 80126, Naples, Italy
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428
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Giri K, Yepes LR, Duncan B, Parameswaran PK, Yan B, Jiang Y, Bilska M, Moyano DF, Thompson M, Rotello VM, Prakash YS. Targeting bacterial biofilms via surface engineering of gold nanoparticles. RSC Adv 2015; 5:105551-105559. [PMID: 26877871 PMCID: PMC4748853 DOI: 10.1039/c5ra16305f] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Bacterial biofilms are associated with persistent infections that are resistant to conventional antibiotics and substantially complicate patient care. Surface engineered nanoparticles represent a novel, unconventional approach for disruption of biofilms and targeting of bacterial pathogens. Herein, we describe the role of surface charge of gold nanoparticles (AuNPs) on biofilm disruption and bactericidal activity towards Staphylococcus aureus and Pseudomonas aeruginosa which are important ventilator associated pneumonia (VAP) pathogens. In addition, we study the toxicity of charged AuNPs on human bronchial epithelial cells. While 100% positively charged AuNP surface was uniformly toxic to both bacteria and epithelial cells, reducing the extent of positive charge on the AuNP surface at moderate concentrations prevented epithelial cell toxicity. Reducing surface charge was however also less effective in killing bacteria. Conversely, increasing AuNP concentration while maintaining a low level of positivity continued to be bactericidal and disrupt the bacterial biofilm and was less cytotoxic to epithelial cells. These initial in vitro studies suggest that modulation of AuNP surface charge could be used to balance effects on bacteria vs. airway cells in the context of VAP, but the therapeutic window in terms of concentration vs. surface positive charge may be limited. Additional factors such as hydrophobicity may need to be considered in order to design AuNPs with specific, beneficial effects on bacterial pathogens and their biofilms.
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Affiliation(s)
- Karuna Giri
- Department of Biochemistry and Molecular Biology, Mayo Clinic, 200 1 St SW, Rochester, MN 55905
| | - Laura Rivas Yepes
- Department of Anesthesiology, Mayo Clinic, 200 1 St SW, Rochester, MN 55905; Department of Physiology & Biomedical Engineering, Mayo Clinic, 200 1 St SW, Rochester, MN 55905
| | - Bradley Duncan
- Department of Chemistry, University of Massachusetts Amherst, 710 North Pleasant Street, Amherst, Massachusetts 01003, United States
| | | | - Bo Yan
- Department of Chemistry, University of Massachusetts Amherst, 710 North Pleasant Street, Amherst, Massachusetts 01003, United States
| | - Ying Jiang
- Department of Chemistry, University of Massachusetts Amherst, 710 North Pleasant Street, Amherst, Massachusetts 01003, United States
| | - Marcela Bilska
- Department of Anesthesiology, Mayo Clinic, 200 1 St SW, Rochester, MN 55905; Department of Physiology & Biomedical Engineering, Mayo Clinic, 200 1 St SW, Rochester, MN 55905
| | - Daniel F Moyano
- Department of Chemistry, University of Massachusetts Amherst, 710 North Pleasant Street, Amherst, Massachusetts 01003, United States
| | - Mike Thompson
- Department of Anesthesiology, Mayo Clinic, 200 1 St SW, Rochester, MN 55905; Department of Physiology & Biomedical Engineering, Mayo Clinic, 200 1 St SW, Rochester, MN 55905
| | - Vincent M Rotello
- Department of Chemistry, University of Massachusetts Amherst, 710 North Pleasant Street, Amherst, Massachusetts 01003, United States
| | - Y S Prakash
- Department of Anesthesiology, Mayo Clinic, 200 1 St SW, Rochester, MN 55905; Department of Physiology & Biomedical Engineering, Mayo Clinic, 200 1 St SW, Rochester, MN 55905
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429
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Batoni G, Casu M, Giuliani A, Luca V, Maisetta G, Mangoni ML, Manzo G, Pintus M, Pirri G, Rinaldi AC, Scorciapino MA, Serra I, Ulrich AS, Wadhwani P. Rational modification of a dendrimeric peptide with antimicrobial activity: consequences on membrane-binding and biological properties. Amino Acids 2015; 48:887-900. [PMID: 26614437 DOI: 10.1007/s00726-015-2136-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Accepted: 11/08/2015] [Indexed: 01/05/2023]
Abstract
Peptide-based antibiotics might help containing the rising tide of antimicrobial resistance. We developed SB056, a semi-synthetic peptide with a dimeric dendrimer scaffold, active against both Gram-negative and Gram-positive bacteria. Being the mechanism of SB056 attributed to disruption of bacterial membranes, we enhanced the amphiphilic profile of the original, empirically derived sequence [WKKIRVRLSA-NH2] by interchanging the first two residues [KWKIRVRLSA-NH2], and explored the effects of this modification on the interaction of peptide, both in linear and dimeric forms, with model membranes and on antimicrobial activity. Results obtained against Escherichia coli and Staphylococcus aureus planktonic strains, with or without salts at physiological concentrations, confirmed the added value of dendrimeric structure over the linear one, especially at physiological ionic strength, and the impact of the higher amphipathicity obtained through sequence modification on enhancing peptide performances. SB056 peptides also displayed intriguing antibiofilm properties. Staphylococcus epidermidis was the most susceptible strain in sessile form, notably to optimized linear analog lin-SB056-1 and the wild-type dendrimer den-SB056. Membrane affinity of all peptides increased with the percentage of negatively charged lipids and was less influenced by the presence of salt in the case of dendrimeric peptides. The analog lin-SB056-1 displayed the highest overall affinity, even for zwitterionic PC bilayers. Thus, in addition to electrostatics, distribution of charged/polar and hydrophobic residues along the sequence might have a significant role in driving peptide-lipid interaction. Supporting this view, dendrimeric analog den-SB056-1 retained greater membrane affinity in the presence of salt than den-SB056, despite the fact that they bear exactly the same net positive charge.
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Affiliation(s)
- Giovanna Batoni
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
| | - Mariano Casu
- Department of Chemical and Geological Sciences, University of Cagliari, Cittadella Universitaria, Monserrato (CA), Italy
| | - Andrea Giuliani
- Research and Development Unit, Spider Biotech S.r.l., Colleretto Giacosa (TO), Italy
| | - Vincenzo Luca
- Dipartimento di Scienze Biochimiche, "A. Rossi Fanelli", Istituto Pasteur-Fondazione Cenci Bolognetti, Sapienza Università di Roma, Rome, Italy
| | - Giuseppantonio Maisetta
- Department of Translational Research and New Technologies in Medicine and Surgery, University of Pisa, Pisa, Italy
| | - Maria Luisa Mangoni
- Dipartimento di Scienze Biochimiche, "A. Rossi Fanelli", Istituto Pasteur-Fondazione Cenci Bolognetti, Sapienza Università di Roma, Rome, Italy
| | - Giorgia Manzo
- Department of Biomedical Sciences, University of Cagliari, Cittadella Universitaria, Monserrato (CA), Italy
| | - Manuela Pintus
- Department of Biomedical Sciences, University of Cagliari, Cittadella Universitaria, Monserrato (CA), Italy
| | - Giovanna Pirri
- Research and Development Unit, Spider Biotech S.r.l., Colleretto Giacosa (TO), Italy
| | - Andrea C Rinaldi
- Department of Biomedical Sciences, University of Cagliari, Cittadella Universitaria, Monserrato (CA), Italy.
| | - Mariano A Scorciapino
- Department of Biomedical Sciences, University of Cagliari, Cittadella Universitaria, Monserrato (CA), Italy
| | - Ilaria Serra
- Department of Biomedical Sciences, University of Cagliari, Cittadella Universitaria, Monserrato (CA), Italy
| | - Anne S Ulrich
- Institute of Biological Interfaces (IBG-2), Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
- Institute of Organic Chemistry, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
| | - Parvesh Wadhwani
- Institute of Biological Interfaces (IBG-2), Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
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430
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Pushing the Limits of MALDI-TOF Mass Spectrometry: Beyond Fungal Species Identification. J Fungi (Basel) 2015; 1:367-383. [PMID: 29376916 PMCID: PMC5753130 DOI: 10.3390/jof1030367] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Revised: 10/05/2015] [Accepted: 10/07/2015] [Indexed: 12/12/2022] Open
Abstract
Matrix assisted laser desorption ionization time of flight (MALDI-TOF) is a powerful analytical tool that has revolutionized microbial identification. Routinely used for bacterial identification, MALDI-TOF has recently been applied to both yeast and filamentous fungi, confirming its pivotal role in the rapid and reliable diagnosis of infections. Subspecies-level identification holds an important role in epidemiological investigations aimed at tracing virulent or drug resistant clones. This review focuses on present and future applications of this versatile tool in the clinical mycology laboratory.
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431
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Buhl M, Peter S, Willmann M. Prevalence and risk factors associated with colonization and infection of extensively drug-resistant Pseudomonas aeruginosa: a systematic review. Expert Rev Anti Infect Ther 2015; 13:1159-70. [PMID: 26153817 DOI: 10.1586/14787210.2015.1064310] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Pseudomonas aeruginosa is a Gram-negative human pathogen with extensively drug-resistant (XDR) strains emerging in hospitals across the globe. This systematic review is focused on the worldwide prevalence of XDR P. aeruginosa (XDR-PA) and on the risk factors associated with its colonization and infection, based on literature available through PubMed, Web of Science and BioMed Central databases. An overview of surveillance systems is provided as well as a synopsis on the prevalence of XDR-PA, showing an increase in recent reports. Risk factors independently associated with XDR-PA colonization or infections are described in four groups with reference to antimicrobial therapy, medical devices as well as patient- and hospital environment-related factors.
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Affiliation(s)
- Michael Buhl
- Institute of Medical Microbiology and Hygiene, University of Tübingen, Tübingen, Germany
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