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Dowler KK, Vientós-Plotts A, Giuliano EA, McAdams ZL, Reinero CR, Ericsson AC. Molecular and microbiological evidence of bacterial contamination of intraocular lenses commonly used in canine cataract surgery. PLoS One 2022; 17:e0277753. [PMID: 36409704 PMCID: PMC9678303 DOI: 10.1371/journal.pone.0277753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Accepted: 10/03/2022] [Indexed: 11/22/2022] Open
Abstract
Inflammatory outcomes, including toxic anterior segment syndrome (TASS) and infectious endophthalmitis, are potentially painful, blinding complications following cataract surgery. In an in vitro pilot study, commercially available, sterile foldable intraocular lenses (IOLs) used during routine canine cataract surgery, and their packaging fluid were surveyed for the presence of bacterial DNA and/or viable (cultivable) bacteria. Swabs from IOLs and packaging fluid from three different veterinary manufacturers and three different production lots/manufacturer were collected for 16S ribosomal ribonucleic acid (rRNA) sequencing. Packaging fluid samples were collected for aerobic/capnophilic bacterial culture. Culture yielded one isolate, identified as Staphylococcus epidermidis. 16S rRNA sequencing revealed distinct brand-specific bacterial DNA profiles, conserved between IOLs and packaging fluid of all production lots within each manufacturer. The dominant taxonomy differentiating each manufacturer was annotated as Staphylococcus sp, and was a 100% match to S. epidermidis. Distinct mixtures of bacterial DNA are present and consistent in IOLs and packaging fluid depending on the manufacturer, and Staphylococcus is the dominant contributor to the bacterial DNA detected. Caralens products had a significantly lower amount of Staphylococcus spp. compared to Anvision and Dioptrix products.
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Affiliation(s)
- Kourtney K. Dowler
- Department of Small Animal Medicine and Surgery, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, United States of America
| | - Aida Vientós-Plotts
- Department of Small Animal Medicine and Surgery, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, United States of America
| | - Elizabeth A. Giuliano
- Department of Small Animal Medicine and Surgery, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, United States of America
| | - Zachary L. McAdams
- Molecular Pathogenesis and Therapeutics Program, University of Missouri, Columbia, Missouri, United States of America
| | - Carol R. Reinero
- Department of Small Animal Medicine and Surgery, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, United States of America
| | - Aaron C. Ericsson
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Columbia, Missouri, United States of America
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Clinical Infections, Antibiotic Resistance, and Pathogenesis of Staphylococcus haemolyticus. Microorganisms 2022; 10:microorganisms10061130. [PMID: 35744647 PMCID: PMC9231169 DOI: 10.3390/microorganisms10061130] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Revised: 05/27/2022] [Accepted: 05/27/2022] [Indexed: 11/16/2022] Open
Abstract
Staphylococcus haemolyticus (S. haemolyticus) constitutes the main part of the human skin microbiota. It is widespread in hospitals and among medical staff, resulting in being an emerging microbe causing nosocomial infections. S. haemolyticus, especially strains that cause nosocomial infections, are more resistant to antibiotics than other coagulase-negative Staphylococci. There is clear evidence that the resistance genes can be acquired by other Staphylococcus species through S. haemolyticus. Severe infections are recorded with S. haemolyticus such as meningitis, endocarditis, prosthetic joint infections, bacteremia, septicemia, peritonitis, and otitis, especially in immunocompromised patients. In addition, S. haemolyticus species were detected in dogs, breed kennels, and food animals. The main feature of pathogenic S. haemolyticus isolates is the formation of a biofilm which is involved in catheter-associated infections and other nosocomial infections. Besides the biofilm formation, S. haemolyticus secretes other factors for bacterial adherence and invasion such as enterotoxins, hemolysins, and fibronectin-binding proteins. In this review, we give updates on the clinical infections associated with S. haemolyticus, highlighting the antibiotic resistance patterns of these isolates, and the virulence factors associated with the disease development.
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Kammoun R, Zmantar T, Ghoul S. Scanning electron microscopy approach to observe bacterial adhesion to dental surfaces. MethodsX 2020; 7:101107. [PMID: 33134101 PMCID: PMC7586140 DOI: 10.1016/j.mex.2020.101107] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Accepted: 10/12/2020] [Indexed: 11/06/2022] Open
Abstract
Bacterial adhesion on dental surfaces depends on the bacterial strain used. The magnification used for observation with a scanning electron microscope depends on the size of the bacteria to be observed. The quality of dental tissues is determinant in the process of bacterial adhesion.
AIM To describe the in vitro bacterial adhesion protocol of Streptococcus mutans and Lactobacillus casei on dental surfaces for a qualitative approach by Scanning Electron Microscopy (SEM) observations. A control and Amelogenesis Imperfecta (AI) affected teeth were used to validate the protocol. METHOD DETAILS Eight teeth were collected and fixed in 10% formalin during 10 days. Crowns were fragmented into 4 parts and kept in the freshly prepared artificial saliva. For the preparation of bacterial suspensions, bacterial strains (S. mutans and L. casei) were incubated in a freshly prepared culture medium. After two successive cultures at 37 °C and 3 rinces, bacterial suspensions were prepared in artificial saliva and adjusted to correspond to 108 CFU ml−1. Bacterial adhesion was carried out by sedimentation. Dental fragments were immersed in bacterial suspensions and rinsed with PBS to remove non adherent bacteria. Adherent bacteria were fixed with glutaraldehyde. Finally, teeth samples were dehydrated, coated, dried and observed using high-resolution SEM (JEOL, JSM-5400). RESULTS SEM observations showed adherence of spheric stuctures, identified as S. mutans and bacilic structures identified as L. casei. CONCLUSION Adhesion of bacteria could be observed by SEM and depends on the quality of dental mineralized tissues.
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Affiliation(s)
- Rym Kammoun
- Laboratory of Histology and Embryology, Faculty of Dental Medicine, University of Monastir, Tunisia.,Laboratory of Dento-Facial, Clinical and Biological Approach (ABCDF), Tunisia
| | - Tarek Zmantar
- Laboratory of Analysis, Treatment and valorization of Pollutants of the Environment and Products, Faculty of Pharmacy, University of Monastir, Avicenna avenue, Monastir 5000, Tunisia
| | - Sonia Ghoul
- Laboratory of Histology and Embryology, Faculty of Dental Medicine, University of Monastir, Tunisia.,Laboratory of Dento-Facial, Clinical and Biological Approach (ABCDF), Tunisia
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Sharma A, Bhat S, Dasgupta D, Samantara L, Kalyanachakravarthi K, Manchanda B, Shah C, Saxena A, Choudhury V, Mondal T. Structure–property correlation of silicone hydrogels based on 3‐[tris(trimethylsilyloxy)silyl]propyl methacrylate monomer. J Appl Polym Sci 2020. [DOI: 10.1002/app.49198] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Asmita Sharma
- Corporate R&DMomentive Performance Materials (India) Pvt. Ltd. Bangalore India
| | - Shreedhar Bhat
- Corporate R&DMomentive Performance Materials (India) Pvt. Ltd. Bangalore India
| | - Debarshi Dasgupta
- Corporate R&DMomentive Performance Materials (India) Pvt. Ltd. Bangalore India
| | - Laxmi Samantara
- Corporate R&DMomentive Performance Materials (India) Pvt. Ltd. Bangalore India
| | | | - Bindu Manchanda
- Department of Material Science and EngineeringIndian Institute of Technology New Delhi India
| | - Chetan Shah
- Corporate R&DMomentive Performance Materials (India) Pvt. Ltd. Bangalore India
| | - Anubhav Saxena
- Corporate R&DMomentive Performance Materials (India) Pvt. Ltd. Bangalore India
| | - Veena Choudhury
- Department of Material Science and EngineeringIndian Institute of Technology New Delhi India
| | - Titash Mondal
- Corporate R&DMomentive Performance Materials (India) Pvt. Ltd. Bangalore India
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Management and Microbiological Characteristics of Membrane Formation on a Hydrophilic Acrylic Intraocular Lens: A Clinical Case Series and Material Comparative Study of Different IOLs. J Ophthalmol 2019; 2019:5746186. [PMID: 30863625 PMCID: PMC6377987 DOI: 10.1155/2019/5746186] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Accepted: 12/02/2018] [Indexed: 11/17/2022] Open
Abstract
Background/Aims. To report a case series of membrane formation on intraocular lenses (IOLs) after uneventful phacoemulsification and to evaluate the material characteristics and biofilm formation on different IOLs. Methods. Ten eyes implanted with the same type of IOLs were found to have membranes on their IOLs after uneventful phacoemulsification from May 2015 to May 2016. No other patients were found with the same phenomenon among 11236 patients who underwent cataract surgeries during this period. To further investigate the reasons for their formation, we assessed seven types of IOLs used in our hospital, including their material characteristics and the presence of microbes (Staphylococcus epidermidis) on the IOL surface by scanning electron microscopy (SEM). All IOLs were incubated under in vitro flow conditions (BioFlux 1000Z). After 36 h, the IOLs were taken from the system, and both the bound bacteria and biofilm formation were observed. Results. Five eyes underwent intravitreal injections of ceftazidime and norvancomycin with one positive culture obtained from the anterior chamber fluid. The other five eyes only received topical treatment of gatifloxacin/levofloxacin and tobramycin. At the last follow-up, all patients had best-corrected visual acuity (BCVA) of 20/50 or better. In the biofilm study on the IOL surface, Staphylococcus epidermidis biofilms formed more readily on hydrophilic acrylic IOLs than on hydrophobic acrylic IOLs. Conclusions. Bacterial adhesion and biofilm tend to develop on certain types of IOLs because of the characteristics of the biomaterial.
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Abstract
Objective: This paper aimed to review the current literature on the surface modification of intraocular lenses (IOLs). Data Sources: All articles about surface modification of IOLs published up to 2015 were identified through a literature search on both PubMed and ScienceDirect. Study Selection: The articles on the surface modification of IOLs were included, but those on design modification and surface coating were excluded. Results: Technology of surface modification included plasma, ion beam, layer-by-layer self-assembly, ultraviolet radiation, and ozone. The main molecules introduced into IOLs surface were poly (ethylene glycol), polyhedral oligomeric silsesquioxane, 2-methacryloyloxyethyl phosphorylcholine, TiO2, heparin, F-heparin, titanium, titanium nitride, vinyl pyrrolidone, and inhibitors of cytokines. The surface modification either resulted in a more hydrophobic lens, a more hydrophilic lens, or a lens with a hydrophilic anterior and hydrophobic posterior surface. Advances in research regarding surface modification of IOLs had led to a better biocompatibility in both in vitro and animal experiments. Conclusion: The surface modification is an efficient, convenient, economic and promising method to improve the biocompatibility of IOLs.
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Affiliation(s)
| | | | | | - Gui-Qin Wang
- Department of Ophthalmology, Navy General Hospital of PLA, Beijing 100048; Department of Ophthalmilogy, Third Clinical Medical College of Southern Medical University, Guangzhou, Guangdong 510515, China
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Analysis of Intraocular Lens Biofilms and Fluids After Long-Term Uncomplicated Cataract Surgery. Am J Ophthalmol 2016; 169:46-57. [PMID: 27318074 DOI: 10.1016/j.ajo.2016.06.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2016] [Revised: 06/05/2016] [Accepted: 06/06/2016] [Indexed: 11/21/2022]
Abstract
PURPOSE Postoperative endophthalmitis is a potentially sight-threatening complication of cataract surgery. However, the pathophysiological mechanisms are not completely understood. We sought to study and evaluate the intraocular environment (aqueous and vitreous humors), the capsular tissue, and the intraocular lens (IOL) surfaces of normal eyes after long-term uncomplicated cataract surgery. DESIGN Experimental laboratory investigation. METHODS We studied 69 eyes donated for transplantation that had previously undergone cataract surgery with posterior chamber IOL implantation and that had no recorded clinical history of postoperative inflammation. We assessed the intraocular environment (DNA traces and biofilm formation) by microbiological evaluation of intraocular fluids using conventional microbiology and molecular techniques, including assessment for the presence of microbes (biofilm formation) on the IOL surface by scanning electron microscopy and ultrastructural capsular remnants by transmission electron microscopy. RESULTS Isolated or aggregated cocci were probable in 18.8% of IOL optic surfaces (n = 13) studied by scanning electron microscopy, suggesting the presence of bacterial biofilm. In 3 intraocular fluid samples for IOLs with biofilm, we identified 16S rDNA by polymerase chain reaction and sequencing. No microbial contamination was found in intraocular fluids by conventional microbiological methods. CONCLUSIONS Our data suggest the possibility of bacterial biofilm formation on the optic surface of IOLs in normal eyes after long-term uncomplicated cataract surgery even in the absence of clinical or subclinical symptoms.
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Scanning Electron Microscopic Analysis of Biofilm Formation in Explanted Human Boston Type I Keratoprostheses. Cornea 2016; 35:25-9. [PMID: 26562818 DOI: 10.1097/ico.0000000000000674] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE To describe the morphological distribution of host tissue and microbial biofilms on the intraocular surfaces of Boston type I keratoprostheses (KPros) explanted because of corneal melt. METHODS Retrospective study of scanning electron microscopy (SEM) images from 4 explanted Boston type I KPros composed of polymethylmethacrylate and titanium. SEM images of KPro-associated ocular surfaces were reviewed for the presence of inflammatory cells, microbes, and/or biofilm formation. One sterile type I KPro was also imaged to serve as a (device only) control. RESULTS All 4 KPros were explanted because of culture-negative, clinically "sterile" donor corneal melt with impending KPro extrusion. In all cases, the rough, irregular surfaces of the device harbored more adherent corneal epithelium and stromacytes, inflammatory cells, and bacteria than the smooth, polished surface of the KPro optic. Two KPros showed not only evidence of prior bacterial colonization but marked biofilm formation. CONCLUSIONS SEM images of explanted KPros explanted for "sterile" corneal melt demonstrated evidence of biofilm formation despite negative donor corneal cultures and the absence of clinical suspicion for infection. These results suggest that "sterile" corneal melt may be due to inflammatory host responses to low microbial burdens as seen in biofilms and/or released antigens after antibiotic-induced lysis. There was increased adherence of host tissue cells and microbial biofilms on the nonpolished surfaces of the KPro. Polishing the intraocular polymethylmethacrylate and titanium KPro surfaces may decrease microbial adhesion and biofilm formation in human subjects with KPros, but what impact this will have on rates of postoperative endophthalmitis is unknown.
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Zhao ZB, An SS, Xie HJ, Han XL, Wang FH, Jiang Y. The Relationship between the Hydrophilicity and Surface Chemical Composition Microphase Separation Structure of Multicomponent Silicone Hydrogels. J Phys Chem B 2015; 119:9780-6. [DOI: 10.1021/acs.jpcb.5b04202] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Zheng-Bai Zhao
- School
of Chemistry and Chemical Engineering, Southeast University, Jiangning, Nanjing, Jiangsu 211189, P. R. China
| | - Shuang-Shuang An
- School
of Chemistry and Chemical Engineering, Southeast University, Jiangning, Nanjing, Jiangsu 211189, P. R. China
| | - Hai-Jiao Xie
- School
of Chemistry and Chemical Engineering, Southeast University, Jiangning, Nanjing, Jiangsu 211189, P. R. China
| | - Xue-Lian Han
- R&D Center, Hydron Contact Lens Co., Ltd, Danyang, Jiangsu 212331, P. R. China
| | - Fu-He Wang
- R&D Center, Hydron Contact Lens Co., Ltd, Danyang, Jiangsu 212331, P. R. China
| | - Yong Jiang
- School
of Chemistry and Chemical Engineering, Southeast University, Jiangning, Nanjing, Jiangsu 211189, P. R. China
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Bispo PJM, Haas W, Gilmore MS. Biofilms in infections of the eye. Pathogens 2015; 4:111-36. [PMID: 25806622 PMCID: PMC4384075 DOI: 10.3390/pathogens4010111] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Revised: 03/12/2015] [Accepted: 03/13/2015] [Indexed: 12/27/2022] Open
Abstract
The ability to form biofilms in a variety of environments is a common trait of bacteria, and may represent one of the earliest defenses against predation. Biofilms are multicellular communities usually held together by a polymeric matrix, ranging from capsular material to cell lysate. In a structure that imposes diffusion limits, environmental microgradients arise to which individual bacteria adapt their physiologies, resulting in the gamut of physiological diversity. Additionally, the proximity of cells within the biofilm creates the opportunity for coordinated behaviors through cell–cell communication using diffusible signals, the most well documented being quorum sensing. Biofilms form on abiotic or biotic surfaces, and because of that are associated with a large proportion of human infections. Biofilm formation imposes a limitation on the uses and design of ocular devices, such as intraocular lenses, posterior contact lenses, scleral buckles, conjunctival plugs, lacrimal intubation devices and orbital implants. In the absence of abiotic materials, biofilms have been observed on the capsule, and in the corneal stroma. As the evidence for the involvement of microbial biofilms in many ocular infections has become compelling, developing new strategies to prevent their formation or to eradicate them at the site of infection, has become a priority.
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Affiliation(s)
- Paulo J M Bispo
- Departments of Ophthalmology, Microbiology and Immunology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, 02114 USA
| | - Wolfgang Haas
- Departments of Ophthalmology, Microbiology and Immunology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, 02114 USA
| | - Michael S Gilmore
- Departments of Ophthalmology, Microbiology and Immunology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, 02114 USA.
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Zhao Z, Xie H, An S, Jiang Y. The Relationship between Oxygen Permeability and Phase Separation Morphology of the Multicomponent Silicone Hydrogels. J Phys Chem B 2014; 118:14640-7. [DOI: 10.1021/jp507682k] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Zhengbai Zhao
- School of Chemistry and Chemical
Engineering, Southeast University, Jiangning, Nanjing, Jiangsu 211189, P. R. China
| | - Haijiao Xie
- School of Chemistry and Chemical
Engineering, Southeast University, Jiangning, Nanjing, Jiangsu 211189, P. R. China
| | - Shuangshuang An
- School of Chemistry and Chemical
Engineering, Southeast University, Jiangning, Nanjing, Jiangsu 211189, P. R. China
| | - Yong Jiang
- School of Chemistry and Chemical
Engineering, Southeast University, Jiangning, Nanjing, Jiangsu 211189, P. R. China
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Parsons C, Jones DS, Gorman SP. The intraocular lens: challenges in the prevention and therapy of infectious endophthalmitis and posterior capsular opacification. Expert Rev Med Devices 2014; 2:161-73. [PMID: 16293053 DOI: 10.1586/17434440.2.2.161] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Cataract is the leading cause of visual impairment worldwide. In the UK, some 30% of the population over 65 years of age have visually impairing cataract. Importantly, 88% of those with treatable visual impairment from cataract are not in contact with any ocular healthcare service, representing a major potential healthcare need [1]. In the USA, it has been estimated that 17.2% of the population (approximately 20.5 million) over 40 years of age have cataract in either eye and by 2020, this number is expected to rise to 30.1 million. Currently, cataract is responsible for 60% of Medicare costs associated with vision [2]. Furthermore, as the populations of industrialized countries such as the UK and the USA continue to age, the costs associated with treatment of cataract can only be expected to increase. Consequently, the development of the intraocular lens to replace the cataractous lens and the advances in intraocular lens design and implantation represent a major development in cataract treatment. However, despite such advances, cataract surgery is not without complications, such as postoperative infectious endophthalmitis, a rare but potentially devastating condition, and posterior capsular opacification, a less serious but much more common problem. This review will examine the epidemiology of cataracts, the polymeric construction of intraocular lenses implanted during cataract surgery and the complications of postoperative infectious endophthalmitis and posterior capsular opacification with regard to therapeutic interventions and prophylactic strategies. Advances in biomaterial design and function will be discussed as novel approaches to prevent such postoperative complications.
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Affiliation(s)
- Carole Parsons
- Medical Devices Group, School of Pharmacy, Queen's University Belfast, 97 Lisburn Road, Belfast BT9 7BL, Northern Ireland, UK.
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Cheng L, Liu Q, Lei Y, Lin Y, Zhang A. The synthesis and characterization of carboxybetaine functionalized polysiloxanes for the preparation of anti-fouling surfaces. RSC Adv 2014. [DOI: 10.1039/c4ra09171j] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Nonspecific protein adsorption and bacterial adhesion have caused serious problems in biomedical devices, marine engineering, membrane separation and many other areas. In this research, a serials of carboxybetaine functionalized polysiloxanes were synthesized and the antifouling properties were demonstrated.
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Affiliation(s)
- Liujun Cheng
- Department of Polymer Material Science and Engineering
- College of Material Science and Engineering
- South China University of Technology
- Guangzhou 510641, China
| | - Qiongqiong Liu
- Department of Polymer Material Science and Engineering
- College of Material Science and Engineering
- South China University of Technology
- Guangzhou 510641, China
| | - Yufeng Lei
- Department of Polymer Material Science and Engineering
- College of Material Science and Engineering
- South China University of Technology
- Guangzhou 510641, China
| | - Yaling Lin
- Department of Pharmaceutical Engineering
- College of Natural Resource and Environment
- South China Agriculture University
- Guangzhou 510642, China
| | - Anqiang Zhang
- Department of Polymer Material Science and Engineering
- College of Material Science and Engineering
- South China University of Technology
- Guangzhou 510641, China
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Cai Y, Strømme M, Zhang P, Engqvist H, Welch K. Photocatalysis induces bioactivity of an organic polymer based material. RSC Adv 2014. [DOI: 10.1039/c4ra08805k] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Bioactivity of resin–TiO2 nanocomposite induced by TiO2 photocatalysis under UV irradiation.
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Affiliation(s)
- Yanling Cai
- Nanotechnology and Functional Materials
- The Ångström Laboratory
- Uppsala University
- Uppsala, Sweden
| | - Maria Strømme
- Nanotechnology and Functional Materials
- The Ångström Laboratory
- Uppsala University
- Uppsala, Sweden
| | - Peng Zhang
- Nanotechnology and Functional Materials
- The Ångström Laboratory
- Uppsala University
- Uppsala, Sweden
| | - Håkan Engqvist
- Applied Materials Science
- The Ångström Laboratory
- Uppsala University
- Uppsala, Sweden
| | - Ken Welch
- Nanotechnology and Functional Materials
- The Ångström Laboratory
- Uppsala University
- Uppsala, Sweden
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Plasma Surface Modification of Rigid Contact Lenses Decreases Bacterial Adhesion. Eye Contact Lens 2013; 39:376-80. [DOI: 10.1097/icl.0b013e31829e8f73] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Baillif S, Leduff F, Hartmann DJ, Kodjikian L. Staphylococcus epidermidis biofilm formation and structural organization on different types of intraocular lenses under in vitro flow conditions. Ophthalmic Res 2013; 50:83-90. [PMID: 23797392 DOI: 10.1159/000350550] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2012] [Accepted: 01/30/2013] [Indexed: 11/19/2022]
Abstract
AIM To compare the adherence and structural organization of Staphylococcus epidermidis biofilm on intraocular lenses (IOLs). METHODS IOLs made of 3 different biomaterials [polymethyl methacrylate (PMMA), hydrophilic acrylic or hydrophobic acrylic] were incubated into an S. epidermidis bacterial solution. Scanning electron microscopy was used to count the bound bacteria and to analyze the structural biofilm architecture. RESULTS After 4-6 h of incubation, adherence was statistically weakest on the hydrophilic acrylic polymer. On the hydrophobic acrylic material, the bacterial cells tended to cover the substratum in a horizontal spread in a continuous monolayer. On the hydrophilic acrylic material or on the PMMA material bacterial cells tended to form only few, small scattered cell clusters. CONCLUSIONS The data suggest that the pattern of S. epidermidis adhesion varies with the IOL biomaterial. Hydrophobic IOLs seem to be more permissive to S. epidermidis adhesion.
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Affiliation(s)
- Stéphanie Baillif
- Department of Ophthalmology, Saint Roch University Hospital, Nice, France
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Scott EM, Esson DW, Fritz KJ, Dubielzig RR. Major breed distribution of canine patients enucleated or eviscerated due to glaucoma following routine cataract surgery as well as common histopathologic findings within enucleated globes. Vet Ophthalmol 2013; 16 Suppl 1:64-72. [PMID: 23406449 DOI: 10.1111/vop.12034] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
PURPOSE To identify the most significantly represented breeds that were enucleated or eviscerated due to intractable glaucoma following elective cataract surgery and to describe the major histopathologic features of enucleated globes. METHODS A retrospective review of the Comparative Ocular Pathology Laboratory of Wisconsin database revealed 153 canine evisceration or enucleation submissions that met inclusion criteria. The most commonly represented breeds were identified, and enucleated globes of these breeds were further evaluated histologically (n = 69). Following standard hematoxylin & eosin staining, globes were evaluated for the presence of; corneal pathology, goniodysgenesis, pigment dispersion, pre-iridal fibrovascular membranes (PIFVMs), peripheral anterior, and/or posterior synechiation, inflammatory infiltrates, lens pathology, retinal pathology, and/or endophthalmitis. RESULTS The most significantly represented breeds were the Cocker Spaniel (11.7%), Boston Terrier (10.5%), Labrador Retriever (6.5%), Bichon Frise (6.5%), Shih Tzu (5.8%), and Jack Russell Terrier (5.8%). Common histopathologic findings included inflammatory keratitis, the presence of PIFVMs, and lymphoplasmacytic uveal infiltrates. CONCLUSIONS The Cocker Spaniel, Boston Terrier, Labrador Retriever, Bichon Frise, Shih Tzu, and Jack Russell Terrier may be at increased risk of the development of glaucoma following elective cataract surgery. These findings have potential clinical implications.
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Affiliation(s)
- Erin M Scott
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, 2015 Linden Drive, Madison, WI 53706, USA
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Klein JP, Torun N, Berndt S, Rieck P, Bertelmann E. [Early in-the-bag spontaneous intraocular lens dislocation of hydrophilic acryl single piece lenses following uncomplicated phacoemulsification]. Ophthalmologe 2012; 109:54-8. [PMID: 22130724 DOI: 10.1007/s00347-011-2447-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
BACKGROUND As techniques for cataract surgery have evolved, spontaneous intraocular lens (IOL) dislocation in patients with no ocular pathology arises less frequently. We present seven consecutive cases of uncomplicated cataract surgery with early in-the-bag spontaneous intraocular lens dislocation for which the same type of hydrophilic single piece lens was used. MATERIAL AND METHODS A retrospective analysis was conducted on seven cases involving patients with IOL dislocation who underwent uncomplicated cataract surgery within a period of 4 months (October 2010 to January 2011) using the same type of single piece IOL. The median age of the 7 patients was 73 years and IOL repositioning was performed after an average of 10 weeks. RESULTS Sulcus repositioning could be carried out in only five of the seven patients and IOL repositioning within the capsule was achieved in one patient. A second patient exhibited IOL dislocation after yttrium aluminium garnet (YAG) laser capsulotomy. Explantation of the IOL and sulcus implantation of another IOL type (Acrysof MA50 MB) was necessary for a third patient. A fourth case presented an angled IOL haptic and dislocation of the IOL in the sulcus position. DISCUSSION Even after uncomplicated cataract surgery, spontaneous in-the-bag IOL dislocation in patients with no ocular pathology may occur due to a hydrophilic lens material which induces stronger anterior capsular phimosis (ACP) in comparison to alternative materials. In combination with a thin lens design this may result in angled IOL haptics and IOL dislocation. CONCLUSIONS Careful selection of suitable lens design and material according to individual predisposing factors is necessary. This retrospective case study demonstrates that the combination of hydrophilic lens material and a thin lens design may result in early spontaneous IOL dislocation. Furthermore, as established in one case, YAG laser capsulotomy may induce IOL dislocation if the lens design cannot withstand capsular fibrosis.
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Affiliation(s)
- J P Klein
- Augenklinik, Campus Virchow Klinikum, Charité-Universitätsmedizin Berlin, Augustenburger Platz 1, 13353, Berlin, Deutschland.
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The effect of ketorolac on biofilm of Staphylococcus epidermidis isolated from post-cataract endophthalmitis. J Ophthalmic Inflamm Infect 2012; 2:89-93. [PMID: 22411461 PMCID: PMC3345053 DOI: 10.1007/s12348-012-0070-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2012] [Accepted: 03/01/2012] [Indexed: 10/29/2022] Open
Abstract
PURPOSE The purpose of this study is to investigate the effect of ketorolac on biofilm formation of Staphylococcus epidermidis isolated from patients with post-cataract endophthalmitis. METHODS Forty S. epidermidis strains isolated from postoperative endophthalmitis were used for this study. Biofilms were grown on microtitre plates for 24 h, dyed, and stained with crystal violet. The mean optical density (OD) and the OD ratio (ODr = OD of the treated biofilm/OD of the untreated biofilm) were used for quantification. The biofilms were incubated with 13 mM ketorolac and without ketorolac for controls. RESULTS The biofilm ODs of the S. epidermidis isolates untreated and treated with ketorolac were significantly different (0.335 ± 0.06 versus 0.158 ± 0.03, respectively; mean ± SD; P < 0.001). Ketorolac reduced S. epidermidis biofilm formation by 47.6 %. CONCLUSIONS Ketorolac, at a concentration of 13 mM, significantly reduces the formation of biofilm by strains of S. epidermidis that caused endophthalmitis.
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Aqueous humor contamination during phacoemulsification in a university teaching hospital. J Fr Ophtalmol 2012; 35:153-6. [DOI: 10.1016/j.jfo.2011.05.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2011] [Revised: 04/22/2011] [Accepted: 05/05/2011] [Indexed: 11/23/2022]
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Chen MY, Chen MJ, Lee PF, Cheng LH, Huang LJ, Lai CH, Huang KH. Towards real-time observation of conditioning film and early biofilm formation under laminar flow conditions using a quartz crystal microbalance. Biochem Eng J 2010. [DOI: 10.1016/j.bej.2010.10.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Kramer S, Schröder AC, Brückner K, Jonescu-Cuypers C, Seitz B. [Subluxation of hydrophilic acrylate intraocular lenses due to massive capsular fibrosis]. Ophthalmologe 2010; 107:460-4. [PMID: 19756637 DOI: 10.1007/s00347-009-2025-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Compared with other biomaterials, hydrophilic acrylate provides better uveal biocompatibility, lower adhesion rates of bacteria and silicone oil, and less glare. Because of reduced capsular biocompatibility, increased fibrosis may initiate dislocation of the intraocular lens (IOL). PATIENTS In six eyes of four patients, enhanced fibroses led to IOL dislocation, leading to an IOL exchange an average of 40 weeks after implantation of the same hydrophilic acrylate lens type. DISCUSSION Predisposing factors were found in 90% of all reported cases of IOL dislocation in the literature, but not in the cases described here. The lens type that was implanted was unable to adapt to the massive fibrosis induced by its hydrophilic biomaterial. CONCLUSIONS The pattern of lens opacification should receive attention when one is choosing an IOL type. Eyes showing pseudoexfoliation syndrome as well as post-uveitis eyes might require a hydrophilic IOL for less cellular reaction, whereas a posterior subcapsular cataract might need a hydrophobic IOL to prevent a massive capsular fibrosis. In the case of increased capsular contraction, unreflected YAG laser capsulotomy may result in IOL subluxation when the lens design cannot handle capsule shrinkage, as demonstrated here.
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Affiliation(s)
- S Kramer
- Klinik für Augenheilkunde, Universitätsklinikum des Saarlandes UKS, Homburg/Saar, Kirrberger Strasse, 66421, Homburg/Saar, Deutschland
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Baillif S, Hartmann D, Freney J, Kodjikian L. [Intraocular lens and bacterial adhesion: influence of the environmental factors, the characteristics of the bacteria, and the target material surface]. J Fr Ophtalmol 2010; 33:210-21. [PMID: 20202716 DOI: 10.1016/j.jfo.2010.01.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2009] [Accepted: 12/22/2009] [Indexed: 10/19/2022]
Abstract
Adhesion of bacteria to intraocular lenses is an important step in the pathogenesis of postoperative endophthalmitis. It can be described as a two-phase process including an initial, instantaneous, and reversible phase followed by a time-dependant and irreversible molecular and cellular phase. The binding of bacteria is affected by many factors including environmental factors such as medium composition, presence of proteins and flow conditions, the bacterial cell surface characteristics, and the material's surface properties. This article reviews all these factors affecting the adhesion of bacteria to intraocular lenses. A better understanding of these mechanisms would make it possible to reduce the bacterial adhesion process and thus could help decrease the incidence of postoperative endophthalmitis.
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Affiliation(s)
- S Baillif
- Département d'Ophtalmologie, Centre hospitalo-universitaire Saint Roch, Nice, France; Laboratoire "Réparation Tissulaire, Interactions Biologiques et Biomatériaux", UPSP 2007.03.135 RTI2B, Lyon, France
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Endophtalmie chronique après chirurgie de la cataracte. J Fr Ophtalmol 2010; 33:105-10. [DOI: 10.1016/j.jfo.2009.12.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2009] [Accepted: 10/15/2009] [Indexed: 11/19/2022]
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Microscopic detection of viable Staphylococcus epidermidis in peri-implant tissue in experimental biomaterial-associated infection, identified by bromodeoxyuridine incorporation. Infect Immun 2010; 78:954-62. [PMID: 20048041 DOI: 10.1128/iai.00849-09] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Infection of biomedical devices is characterized by biofilm formation and colonization of surrounding tissue by the causative pathogens. To investigate whether bacteria detected microscopically in tissue surrounding infected devices were viable, we used bromodeoxyuridine (BrdU), a nucleotide analogue that is incorporated into bacterial DNA and can be detected with antibodies. Infected human tissue was obtained postmortem from patients with intravascular devices, and mouse biopsy specimens were obtained from mice with experimental biomaterial infection. In vitro experiments showed that Staphylococcus epidermidis incorporated BrdU, as judged from staining of the bacteria with anti-BrdU antibodies. After incubation of bacteria with BrdU and subsequent staining of microscopic sections with anti-BrdU antibodies, bacteria could be clearly visualized in the tissue surrounding intravascular devices of deceased patients. With this staining technique, relapse of infection could be visualized in mice challenged with a low dose of S. epidermidis and treated with dexamethasone between 14 and 21 days after challenge to suppress immunity. This confirms and extends our previous findings that pericatheter tissue is a reservoir for bacteria in biomaterial-associated infection. The pathogenesis of the infection and temporo-spatial distribution of viable, dividing bacteria can now be studied at the microscopic level by immunolabeling with BrdU and BrdU antibodies.
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Aydinuraz K, Ağalar C, Ağalar F, Çeken S, Duruyürek N, Vural T. In Vitro S. epidermidis and S. aureus Adherence to Composite and Lightweight Polypropylene Grafts. J Surg Res 2009; 157:e79-86. [DOI: 10.1016/j.jss.2009.04.008] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2009] [Revised: 02/20/2009] [Accepted: 04/01/2009] [Indexed: 11/16/2022]
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Shimizu K, Kobayakawa S, Tsuji A, Tochikubo T. Biofilm Formation on Hydrophilic Intraocular Lens Material. Curr Eye Res 2009; 31:989-97. [PMID: 17169836 DOI: 10.1080/02713680601038816] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
PURPOSE To estimate bacterial biofilm formation on the hydrophilic acrylic (hydrogel) intraocular lens (IOL) Meridian (HP60M, Baush & Lomb) and to investigate a preventive effect against biofilm formation of hydrogel IOLs presoaked in antibiotics. METHODS Two Staphylococcus epidermidis strains, ATCC 12228 and ATCC 35984 (biofilm-producer), and an Enterococcus faecalis strain (KOS1, clinical isolate from an endophthalmitis patient) were used. Biofilms were cultivated on disks of different IOL materials: hydrogel, PMMA (polymethylmethacrylate), and acrylic. Biofilms were stained with crystal violet (CV), which served as an index of biofilm formation. The bacterial population was enumerated after biofilm homogenization. Biofilms were also examined by scanning electron microscopy (SEM). IOLs were presoaked in two antibiotics, levofloxacin (LVFX) and gatifloxacin (GFLX), and then the bacterial population was enumerated. As in vivo experiment, antibiotics-treated and nontreated Meridian IOLs were implanted in rabbit eyes, which served as an endophthalmitis model, and the bacterial population was enumerated. RESULTS The amount of biofilm formed was the least on hydrogel from among the three materials tested after 48- and 72-hr incubation (p < 0.05 to 0.01). The bacterial population was the least on hydrogel from among the three materials with ATCC 12228 (p < 0.05 to 0.01), and the bacterial population was significantly different between hydrogel and acrylic after 72-hr incubation with ATCC 35984 (p < 0.05). Biofilm by the two S. epidermidis strains were recognized after 24-hr incubation. Rates of biofilm-positive SEM fields, which were defined as being occupied by biofilm over at least half of the area, were increased through 72 hr with ATCC 35984. While the E. faecalis strain showed no bacterial adherence on the antibiotics-treated hydrogel IOLs, adherence of the S. epidermidis strain, ATCC 35984 was recognized on the LVFX-treated IOLs after 48-hr incubation (103 to 104 CFU/ml). In the rabbit in vivo model, the bacterial populations in eyes with an antibiotics-treated Meridian IOL were significantly smaller than in eyes with a nontreated IOL for 72 hr after surgery (p < 0.05 to 0.01). CONCLUSIONS The biofilm formation was less on hydrogel than on other two materials tested. Hydrogel presoaked in antibiotics exhibited a preventive effect against biofilm formation at least for 24 hr in vitro and against bacterial proliferation in the rabbit in vivo endophthalmitis model.
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Affiliation(s)
- Kohei Shimizu
- The First Department of Ophthalmology, School of Medicine, Toho University, Tokyo, Japan
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Tang H, Cao T, Liang X, Wang A, Salley SO, McAllister J, Ng KYS. Influence of silicone surface roughness and hydrophobicity on adhesion and colonization ofStaphylococcus epidermidis. J Biomed Mater Res A 2009; 88:454-63. [DOI: 10.1002/jbm.a.31788] [Citation(s) in RCA: 91] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Parsons C, McCoy CP, Gorman SP, Jones DS, Bell SE, Brady C, McGlinchey SM. Anti-infective photodynamic biomaterials for the prevention of intraocular lens-associated infectious endophthalmitis. Biomaterials 2009; 30:597-602. [DOI: 10.1016/j.biomaterials.2008.10.015] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2008] [Accepted: 10/21/2008] [Indexed: 12/21/2022]
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Gazzola S, Cocconcelli PS. Vancomycin heteroresistance and biofilm formation in Staphylococcus epidermidis from food. MICROBIOLOGY-SGM 2008; 154:3224-3231. [PMID: 18832327 DOI: 10.1099/mic.0.2008/021154-0] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Staphylococcus epidermidis CNBL 7032 is a heteroresistant strain, with subpopulations resistant to vancomycin concentrations up to 32 mg l (-1), which was isolated from cured pork meat. The mechanisms of glycopeptide resistance in this strain were investigated in this study. S. epidermidis CNBL 7032 does not harbour enterococcal transmissible vancomycin-resistance genes. Transmission electron microscopy revealed that resistant subpopulations have a thicker cell wall, and that the increase in cell wall thickness is proportional to vancomycin concentration in the growth medium. Scanning electron microscopy showed that S. epidermidis CNBL 7032 forms a biofilm-like structure when grown in the presence of vancomycin. This food isolate harbours the gene atlE, coding for an autolysin with an adhesive function, which is involved in the first phase of biofilm formation. This study has demonstrated an interaction between atlE expression, biofilm formation and glycopeptide antibiotic resistance; transcription analysis demonstrated that the expression of atlE increased proportionally with the vancomycin concentration in the culture. Insertional inactivation of atlE confirmed the role of the AtlE autolysin in biofilm and vancomycin resistance.
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Affiliation(s)
- Simona Gazzola
- Istituto di Microbiologia, Università Cattolica del Sacro Cuore, via Emilia Parmense 84, 29100 Piacenza, Italy
| | - Pier Sandro Cocconcelli
- Istituto di Microbiologia, Università Cattolica del Sacro Cuore, via Emilia Parmense 84, 29100 Piacenza, Italy
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Kelkar A, Kelkar J, Amuaku W, Kelkar U, Shaikh A. How to prevent endophthalmitis in cataract surgeries? Indian J Ophthalmol 2008; 56:403-7. [PMID: 18711270 PMCID: PMC2636140 DOI: 10.4103/0301-4738.42418] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Postoperative endophthalmitis is a very devastating complication and every step should be taken to reduce its occurrence. Unattended air conditioning filter systems are often the culprits and regular maintenance of the filters is of paramount importance. Shedders of pathogenic organisms amongst the theater personnel should be identified by regular screening and should be promptly treated. In addition to the use of Povidone iodine 5% solution in the conjunctival sac few minutes prior to surgery, proper construction of wound, injectable intraocular lenses, use of prophylactic intracameral antibiotics or prophylactic subconjunctival antibiotic injection at the conclusion of cataract surgery, placing a patch after the surgery for at least 4 h and initiating topical antibiotics from the same day of surgery helps to lower the frequency of postoperative endophthalmitis. Intraoperative posterior capsule rupture and anterior vitrectomy are risk factors for acute endophthalmitis, and utmost care to prevent posterior capsular rent should be taken while performing cataract surgery. Also, in case of such complication, these patients should be closely monitored for early signs of endophthalmitis in the postoperative period. In the unfortunate event of endophthalmitis the diagnosis should be prompt and treatment must be initiated as early as possible.
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Katsikogianni M, Amanatides E, Mataras D, Missirlis YF. Staphylococcus epidermidis adhesion to He, He/O(2) plasma treated PET films and aged materials: contributions of surface free energy and shear rate. Colloids Surf B Biointerfaces 2008; 65:257-68. [PMID: 18565741 DOI: 10.1016/j.colsurfb.2008.04.017] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2007] [Revised: 04/22/2008] [Accepted: 04/23/2008] [Indexed: 10/22/2022]
Abstract
Adhesion studies of bacteria (Staphylococcus epidermidis) to plasma modified PET films were conducted in order to determine the role of the surface free energy under static and dynamic conditions. In particular, we investigated the effect of the ageing time on the physicochemical surface properties of helium (He) and 20% of oxygen in helium (He/O(2)) plasma treated polyethylene terephthalate (PET) as well as on the bacterial adhesion. Treatment conditions especially known to result in ageing sensitive hydrophilicity (hydrophobic recovery) were intentionally chosen in an effort to obtain the widest possible range of surface energy specimens and also to avoid strong changes in the morphological properties of the surface. Both plasma treatments are shown to significantly reduce bacterial adhesion in comparison to the untreated PET. However, the ageing effect and the subsequent decrease in the surface free energy of the substratum surfaces with time - especially in the case of He treated samples - seem to favor bacterial adhesion and aggregation. The dispersion-polar and the Lifshitz-van der Waals (LW) acid-base (AB) thermodynamic approaches were applied to calculate the Gibbs free energy changes of adhesion (DeltaG(adh)) of S. epidermidis interacting with the substrates. There was a strong correlation between the thermodynamic predictions and the measured values of bacterial adhesion, when adhesion was performed under static conditions. By decoupling the (DeltaG(adh)) values into their components, we observed that polar/acid-base interactions dominated the interactions of bacteria with the substrates in aqueous media. However, under flow conditions, the increase in the shear rate restricted the predictability of the thermodynamic models.
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Affiliation(s)
- M Katsikogianni
- Laboratory of Biomechanics and Biomedical Engineering, Department of Mechanical Engineering and Aeronautics, University of Patras, Patras 26504, Greece
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Baillif S, Ecochard R, Casoli E, Freney J, Burillon C, Kodjikian L. Adherence and kinetics of biofilm formation of Staphylococcus epidermidis to different types of intraocular lenses under dynamic flow conditions. J Cataract Refract Surg 2008; 34:153-8. [PMID: 18165096 DOI: 10.1016/j.jcrs.2007.07.058] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2007] [Accepted: 07/30/2007] [Indexed: 10/22/2022]
Abstract
PURPOSE To compare the adherence and biofilm formation of Staphylococcus epidermidis under in vitro flow conditions on intraocular lenses (IOLs) made of 4 biomaterials: poly(methyl methacrylate) (PMMA), silicone, hydrophilic acrylic, and hydrophobic acrylic. SETTING Department of Ophthalmology, Croix-Rousse University Hospital and University Research Laboratory, Lyon, France. METHODS Intraocular lenses were placed in a bioreactor designed to replicate intraocular conditions. The model consisted of Tygon tubing connected to a vial. Three septa allowed the entry and elimination of the artificial aqueous humor and inoculation of the bacterial suspension. The first of 2 pumps moved the aqueous humor along the circuit; the second pump regulated the flow at which the nutritive environment was regenerated. At various times (12, 16, 24, 40, 48, 60, and 72 hours), IOLs were taken from this environment and the bound bacteria were removed and counted. The distribution of bacterial adhesion on the IOLs was modeled using polynomial Poisson regression. To test the effect of the IOL biomaterial on bacterial adhesion, likelihood ratio tests were performed. RESULTS The model provided the kinetics of S epidermidis biofilm growth on IOLs. The biofilm growth on each of the 4 biomaterials occurred in 3 phases: latent, dynamic or accelerated growth, and linear growth. The extent of bacterial binding to IOLs increased from hydrophilic acrylic polymer to PMMA, hydrophobic acrylic, and silicone. The differences were statistically significant. CONCLUSION Bacterial adhesion to and biofilm development on the IOL surface depended on the characteristics of the biomaterial.
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Affiliation(s)
- Stéphanie Baillif
- Department of Ophthalmology, Croix-Rousse University Hospital, Lyon, France
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Bacterial adhesion to conventional hydrogel and new silicone-hydrogel contact lens materials. Graefes Arch Clin Exp Ophthalmol 2007; 246:267-73. [DOI: 10.1007/s00417-007-0703-5] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2007] [Revised: 09/21/2007] [Accepted: 10/01/2007] [Indexed: 11/25/2022] Open
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Huang XD, Yao K, Zhang H, Huang XJ, Xu ZK. Surface modification of silicone intraocular lens by 2-methacryloyloxyethyl phosphoryl-choline binding to reduce Staphylococcus epidermidis adherence. Clin Exp Ophthalmol 2007; 35:462-7. [PMID: 17651252 DOI: 10.1111/j.1442-9071.2007.01516.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
PURPOSE To analyse the in vitro adherence of Staphylococcus epidermidis to the 2-methacryloyl oxyethyl phosphorylcholine (MPC)-modified silicone intraocular lens (IOL). METHODS The test IOLs were modified by using an air plasma treatment to bind MPC to the surface. The control IOLs were not modified. Chemical changes on the IOL surface were analysed by X-ray photoelectron spectroscopy (XPS) to confirm the covalent binding of MPC. IOL hydrophilicity was determined by measuring the water contact angle. Two different techniques, direct counting of viable adherent bacteria released by sonication, and scanning electron microscopy (SEM), were used to observe and compare the adherence of S. epidermidis to the IOLs after 1- and 18-h incubation. RESULTS XPS analysis confirmed that the test IOLs were surface-modified with MPC. The hydrophilicity of the IOLs was improved by surface modification, and the MPC-modified IOLs exhibited significantly reduced adhesion of S. epidermidis (P = 0.002) after an incubation period of 1 h. The SEM results showed that the MPC modification also suppressed the accumulation of bacteria and biofilm production after 18 h incubation. CONCLUSIONS MPC-modified hydrophilic silicone IOLs reduce bacterial adherence and colonization, and thus may help reduce the incidence of postoperative endophthalmitis.
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Affiliation(s)
- Xiao-Dan Huang
- Eye Center, Affiliated Second Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
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Santos L, Rodrigues D, Lira M, Oliveira R, Real Oliveira MECD, Vilar EYP, Azeredo J. The Effect of Octylglucoside and Sodium Cholate in Staphylococcus epidermidis and Pseudomonas aeruginosa Adhesion to Soft Contact Lenses. Optom Vis Sci 2007; 84:429-34. [PMID: 17502827 DOI: 10.1097/opx.0b013e318058a0cc] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
PURPOSE In this study, the effect of the natural surfactants octylglucoside and sodium cholate in inhibiting Staphylococcus epidermidis and Pseudomonas aeruginosa adhesion to conventional and silicone-hydrogel contact lenses (CL) was assessed. Hydrophobicity was also evaluated to conditioned and nonconditioned CL. METHODS The inhibiting effect of the tested surfactants was determined through "in vitro" adhesion studies to conditioned and nonconditioned CL followed by image acquisition and cell enumeration. Hydrophobicity was evaluated through contact angle measurements using the advancing type technique on air. RESULTS Sodium cholate exhibits a very low capability to inhibit microbial adhesion. Conversely, octylglucoside effectively inhibited microbial adhesion in both types of lenses. This surfactant exhibited an even greater performance than a multipurpose lens care solution used as control. Octylglucoside was the only tested surfactant able to lower the hydrophobicity of all CL, which can explain its high performance. CONCLUSIONS The results obtained in this study point out the potential of octylglucoside as a conditioning agent to prevent microbial colonization.
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Affiliation(s)
- Lívia Santos
- Instituto de Biotecnologia e Bioengenharia, Centro de Engenharia Biológica, Universidade do Minho, Minho, Portugal
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Kodjikian L, Beby F, Rabilloud M, Bruslea D, Halphen I, Fleury J, Grange JD, Garweg JG. Influence of intraocular lens material on the development of acute endophthalmitis after cataract surgery? Eye (Lond) 2006; 22:184-93. [PMID: 16980932 DOI: 10.1038/sj.eye.6702544] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
PURPOSE To investigate the causal relationship between acute postoperative endophthalmitis (POE) after cataract surgery and the biomaterial properties of the intraocular lens (IOLs) implanted. METHODS This retrospective cohort study included all patients who had undergone cataract surgery with IOL implantation at the Lyon Croix-Rousse University Hospital between 1st January 1994 and 31st December 2004. Details respecting the type of IOL implanted (material and manufacturer) were meticulously recorded. The number of patients presenting with POE within 6 weeks of cataract surgery was documented together with their medical characteristics. These data were then compared, and Fisher's exact test was used to establish the significance of any apparent associations. RESULTS Eight of the 5837 eyes manifested acute POE (0.14%). Seven of these were composed of polymethylmethacrylate (PMMA) and one of heparinized PMMA. Patients with PMMA IOLs carried a higher risk of developing POE than did those implanted with either heparinized PMMA (P=0.001), hydrophilic acrylic, or hydrophobic acrylic IOLs (P=0.002). CONCLUSIONS The incidence of acute POE after cataract surgery in our hospital is similar to that currently reported for other institutions in developed countries. Our results add further evidence that IOL material and type are factors contributing to the risk to develop an acute POE after cataract surgery, and that PMMA IOLs may be associated with an increased risk of POE.
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Affiliation(s)
- L Kodjikian
- Department of Ophthalmology, Croix-Rousse Hospital, University of Lyon I Claude Bernard, Lyon, France.
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Kienast A, Kämmerer R, Weiss C, Klinger M, Menz DH, Dresp J, Ohgke H, Solbach W, Laqua H, Hoerauf H. Influence of a new surface modification of intraocular lenses with fluoroalkylsilan on the adherence of endophthalmitis-causing bacteria in vitro. Graefes Arch Clin Exp Ophthalmol 2006; 244:1171-7. [PMID: 16453124 DOI: 10.1007/s00417-005-0242-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2005] [Revised: 11/02/2005] [Accepted: 12/11/2005] [Indexed: 10/25/2022] Open
Abstract
INTRODUCTION Dynasilan is a fluoroalkylsilan that is able to interact with surface active centres on intraocular lenses (IOL), offering a new way for surface modification of different IOL materials. The purpose of this in vitro study was to investigate the influence of this new surface modification on the adherence of two typical endophthalmitis causing bacteria (Staphylococcus epidermidis, Propionibacterium acnes). MATERIALS AND METHODS In a pilot experiment, the effect of Dynasilan coating on the adherence of S. epidermidis was tested on glass slides. Forty-two Dynasilan-modified and 42 unmodified IOL (14 PMMA, 14 silicone and 14 hydrogel) were incubated at 37 degrees C in brain heart infusion broth (10(8) CFU/ml) with either S. epidermidis for 24 h or with P. acnes for 1 h. Subsequently, the adherent bacteria were resuspended using ultrasonification at 35 kHz for 3x45 s. After dilution series and incubation at 37 degrees C on Petri dishes for 24 h and 3 days, respectively, the colonies were counted. RESULTS In the pilot experiment, a markedly lower number of adherent S. epidermidis was observed on Dynasilan-modified glass slides. Of all IOL materials incubated with S. epidermidis, those modified with Dynasilan showed a lower mean number of adherent bacteria (mean 1.37x10(7); SD 2.37x10(7)) than those untreated (2.43x10(7); SD 3.04x10(7)). IOLs incubated with P. acnes showed a significantly lower mean number of adherent bacteria of 2.51x10(4) (SD 2.71x10(4)) on Dynasilan-modified IOLs versus 6.27x10(4) (SD 7.70x10(4)) on untreated IOLs. CONCLUSION The presented in vitro results indicate that Dynasilan surface modification is able to reduce the adherence of S. epidermidis and P. acnes on all IOL materials tested. Further studies regarding the stability of this modification and its biocompatibility must be performed.
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Kodjikian L, Roques C, Pellon G, Renaud F, Hartmann D, Freney J, Burillon C. Adhésion bactérienne aux implants intraoculaires et prévention de l'endophtalmie. J Fr Ophtalmol 2006; 29:74-81. [PMID: 16465128 DOI: 10.1016/s0181-5512(06)73753-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Bacterial adhesion to intraocular lenses (IOLs) during their implantation is a major etiological factor of postoperative endophthalmitis. Polypropylene was the first biomaterial that allowed this relation of cause and effect between bacterial adhesion and endophthalmitis to be proven. Adhesion to IOLs has been investigated in several in vitro studies, with contradictory results reported, due to variations in experimental conditions: the incubation times and the methods all varied. Adhesion is affected by the type of IOL, the bacterial strains, and the surrounding medium. Since this medium is very difficult to model because of its complexity, in vivo studies seemed essential. We have recently determined in vivo progression in the amount of adhering Staphylococcus epidermidis to five types of IOLs. There have been few epidemiological studies published to determine the relationship between endophthalmitis and the IOL type. However, the perfect biomaterial that could prevent postoperative endophthalmitis does not yet exist. Globally, hydrophilic materials and hydrophobic acrylic seem to be less sticky than silicone or PMMA, but this remains to be proven clinically.
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Affiliation(s)
- L Kodjikian
- Département d'Ophtalmologie, Hôpital de la Croix-Rousse, Lyon, France.
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Kobayakawa S, Jett BD, Gilmore MS. Biofilm formation by Enterococcus faecalis on intraocular lens material. Curr Eye Res 2005; 30:741-5. [PMID: 16146919 DOI: 10.1080/02713680591005959] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
PURPOSE To compare biofilm formation by Enterococcus faecalis on different intraocular lens (IOL) materials. METHODS E. faecalis biofilms were cultivated on disks of IOL material (silicone, PMMA [polymethylmethacrylate], or acrylic). Biofilms were stained with crystal violet (CV), which served as an index of biofilm formation. The bacterial population was enumerated after biofilm homogenization. Biofilms were also examined by confocal microscopy. RESULTS At 24 hr, there was no significant difference in biofilm formation, or the population within biofilms, among the three materials tested. However, after 48 and 72 hr, it was observed that silicone supported the least amount of biofilm formation (p < 0.05); biomass on PMMA and acrylic IOLs continued to increase, with acrylic demonstrating the greatest amount of stainable biofilm (p < 0.0005). The population on PMMA was significantly greater than the other IOL materials (p < 0.005). Confocal microscopy confirmed the lack of biomass on silicone. CONCLUSIONS Among three IOL materials, E. faecalis biofilms formed more readily on PMMA and acrylic compared to silicone.
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Affiliation(s)
- Shinichiro Kobayakawa
- Schepens Eye Research Institute, Harvard Medical School, Boston, Massachusetts 02114, USA
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Kodjikian L, Roques C, Baillif S, Pellon G, Hartmann D, Freney J, Burillon C. Endophtalmie : étiopathogénie et antibioprophylaxie. J Fr Ophtalmol 2005; 28:1122-30. [PMID: 16395208 DOI: 10.1016/s0181-5512(05)81151-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Postoperative endophthalmitis is still one of the most fearsome complications of cataract surgery. The present review's aims are to study the etiology and pathogenesis of endophthalmitis and the criteria for antibiotic prophylaxis. Endophthalmitis prevalence is 0.07%-0.32% in cataract surgery. The clinical presentation needs to be perfectly known, even if none of the signs is pathognomonic. Bacteria predominantly cultured in postoperative endophthalmitis are gram-positive, especially Staphylococcus epidermidis. Most of the bacteria come from the patient. Bacterial adhesion to intraocular lenses (IOLs) takes place during their implantation, a prominent etiological factor. Polypropylene was the first biomaterial that proved this relation of cause and effect between bacterial adhesion and endophthalmitis. The benefit of antibiotic prophylaxis during cataract surgery has yet not been proven, since the low prevalence of endophthalmitis makes controlled studies with a large cohort difficult. The criteria and the four possible administration approaches (topical, subconjunctival, irrigation liquid, systemic) are analyzed.
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Affiliation(s)
- L Kodjikian
- Département d'Ophtalmologie, Hôpital de la Croix-Rousse, Lyon, France.
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Kodjikian L, Renaud FNR, Roques C, Garweg JG, Pellon G, Freney J, Burillon C. In vitro influence of vancomycin on adhesion of a Staphylococcus epidermidis strain encoding intercellular adhesion locus ica to intraocular lenses. J Cataract Refract Surg 2005; 31:1050-8. [PMID: 15975477 DOI: 10.1016/j.jcrs.2004.07.026] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/15/2004] [Indexed: 11/16/2022]
Abstract
PURPOSE To assess anti-adhesion and/or bactericidal properties of vancomycin in vitro and to determine when these effects are detectable to estimate its relevance to perioperative antibiotic prophylaxis and analyze the efficacy of a newly designed vancomycin insert prototype for endophthalmitis prevention. SETTING University research laboratory, Lyon, France. METHODS Staphylococcus epidermidis clinical strain N890074 containing the intercellular adhesion locus ica was used as the infectious agent. Vancomycin was used at 20 microg/mL. A sterile biocompatible, biodegradable vancomycin insert, releasing 230 microg of antibiotics over 100 minutes, was designed especially for this study. To obtain bacterial killing curves, experiments were first performed in a 103 colony-forming units (CFU/mL) bacterial suspension containing no intraocular lenses (IOL). Then IOLs were incubated in the suspension, and bacterial adherence was determined using bacterial counting with and without antibiotic. RESULTS Vancomycin (solution and insert) had an anti-adhesion effect after 1 hour and a relevant bactericidal effect after 6 hours of incubation. CONCLUSIONS Vancomycin used with irrigating solutions does not remain in the anterior chamber long enough to develop bactericidal effect. Even if it initially reduces bacterial adhesion, used at a drug level dropping below the bacterial minimal inhibitory concentration, it could result in a secondary increase of the adhesion of slime-producing bacteria. A sufficiently high concentration was obtained in vitro by the new sustained-release system, thereby overcoming the theoretical drawback of a short half-life within the anterior chamber. Anti-adhesion and bactericidal action of vancomycin inserts remains to be confirmed in clinical studies.
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Affiliation(s)
- Laurent Kodjikian
- Department of Ophthalmology, Croix-Rousse Hospital, Lyon 69004, France.
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Pavon-Djavid G, Hélary G, Migonney V. « Les biomatériaux inhibiteurs de l'adhérence et de la prolifération bactérienne : un enjeu pour la prévention des infections sur matériel prothétique ». ACTA ACUST UNITED AC 2005. [DOI: 10.1016/j.rbmret.2005.04.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Kodjikian L, Roques C, Campanac C, Doleans A, Baillif S, Pellon G, Renaud FNR, Hartmann D, Freney J, Burillon C. Biofilms à Staphylococcus epidermidis à la surface des implants intraoculaires. J Fr Ophtalmol 2005; 28:224-30. [PMID: 15851958 DOI: 10.1016/s0181-5512(05)81047-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Bacterial adhesion to intraocular lenses (IOLs) takes place during their implantation. This is a prominent etiological factor of postoperative endophthalmitis. Following adhesion, secretion of an extracellular matrix (called slime for Staphylococcus epidermidis) and formation of multiple layers of microcolonies lead to the colonization of the biomaterial surface. Scanning electron microscopy photographs illustrate the different steps of biofilm formation. The different adhesins expressed by S. epidermidis involved in the adhesion process are described. The biofilm is not only an adhesive medium; it also affects virulence. Last, notions on biofilm physiology are discussed in an attempt to explain the dynamic equilibrium of this system. In 2004, the perfect biomaterial able to prevent postoperative endophthalmitis does not yet exist. Moreover, there is no effective tool, at the present time, to fight against mature biofilms. Therefore, preventing biofilm formation remains capital, which requires perfect knowledge of all stages of formation and the factors involved.
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Affiliation(s)
- L Kodjikian
- Hôpital de la Croix-Rousse, Département d'Ophtalmologie, 103, Grande Rue de la Croix-Rousse, 69004 Lyon, France.
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Lin CH, Lin JC, Chen CY, Cheng CY, Lin XZ, Wu JJ. Feasibility evaluation of chitosan coatings on polyethylene tubing for biliary stent applications. J Appl Polym Sci 2005. [DOI: 10.1002/app.21844] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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