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Li Y, Shi Y, Lu Y, Li X, Zhou J, Zadpoor AA, Wang L. Additive manufacturing of vascular stents. Acta Biomater 2023:S1742-7061(23)00338-0. [PMID: 37331614 DOI: 10.1016/j.actbio.2023.06.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 06/11/2023] [Accepted: 06/13/2023] [Indexed: 06/20/2023]
Abstract
With the advancement of additive manufacturing (AM), customized vascular stents can now be fabricated to fit the curvatures and sizes of a narrowed or blocked blood vessel, thereby reducing the possibility of thrombosis and restenosis. More importantly, AM enables the design and fabrication of complex and functional stent unit cells that would otherwise be impossible to realize with conventional manufacturing techniques. Additionally, AM makes fast design iterations possible while also shortening the development time of vascular stents. This has led to the emergence of a new treatment paradigm in which custom and on-demand-fabricated stents will be used for just-in-time treatments. This review is focused on the recent advances in AM vascular stents aimed at meeting the mechanical and biological requirements. First, the biomaterials suitable for AM vascular stents are listed and briefly described. Second, we review the AM technologies that have been so far used to fabricate vascular stents as well as the performances they have achieved. Subsequently, the design criteria for the clinical application of AM vascular stents are discussed considering the currently encountered limitations in materials and AM techniques. Finally, the remaining challenges are highlighted and some future research directions are proposed to realize clinically-viable AM vascular stents. STATEMENT OF SIGNIFICANCE: Vascular stents have been widely used for the treatment of vascular disease. The recent progress in additive manufacturing (AM) has provided unprecedented opportunities for revolutionizing traditional vascular stents. In this manuscript, we review the applications of AM to the design and fabrication of vascular stents. This is an interdisciplinary subject area that has not been previously covered in the published review articles. Our objective is to not only present the state-of-the-art of AM biomaterials and technologies but to also critically assess the limitations and challenges that need to be overcome to speed up the clinical adoption of AM vascular stents with both anatomical superiority and mechanical and biological functionalities that exceed those of the currently available mass-produced devices.
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Affiliation(s)
- Yageng Li
- Beijing Advanced Innovation Center for Materials Genome Engineering, School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Yixuan Shi
- Beijing Advanced Innovation Center for Materials Genome Engineering, School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Yuchen Lu
- Beijing Advanced Innovation Center for Materials Genome Engineering, School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Xuan Li
- Beijing Advanced Innovation Center for Materials Genome Engineering, School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Jie Zhou
- Department of Biomechanical Engineering, Delft University of Technology, Delft 2628 CD, The Netherlands.
| | - Amir A Zadpoor
- Department of Biomechanical Engineering, Delft University of Technology, Delft 2628 CD, The Netherlands.
| | - Luning Wang
- Beijing Advanced Innovation Center for Materials Genome Engineering, School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing, 100083, China.
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Wang L, Jiao L, Pang S, Yan P, Wang X, Qiu T. The Development of Design and Manufacture Techniques for Bioresorbable Coronary Artery Stents. MICROMACHINES 2021; 12:mi12080990. [PMID: 34442612 PMCID: PMC8398368 DOI: 10.3390/mi12080990] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 08/18/2021] [Accepted: 08/18/2021] [Indexed: 02/02/2023]
Abstract
Coronary artery disease (CAD) is the leading killer of humans worldwide. Bioresorbable polymeric stents have attracted a great deal of interest because they can treat CAD without producing long-term complications. Bioresorbable polymeric stents (BMSs) have undergone a sustainable revolution in terms of material processing, mechanical performance, biodegradability and manufacture techniques. Biodegradable polymers and copolymers have been widely studied as potential material candidates for bioresorbable stents. It is a great challenge to find a reasonable balance between the mechanical properties and degradation behavior of bioresorbable polymeric stents. Surface modification and drug-coating methods are generally used to improve biocompatibility and drug loading performance, which are decisive factors for the safety and efficacy of bioresorbable stents. Traditional stent manufacture techniques include etching, micro-electro discharge machining, electroforming, die-casting and laser cutting. The rapid development of 3D printing has brought continuous innovation and the wide application of biodegradable materials, which provides a novel technique for the additive manufacture of bioresorbable stents. This review aims to describe the problems regarding and the achievements of biodegradable stents from their birth to the present and discuss potential difficulties and challenges in the future.
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Affiliation(s)
- Liang Wang
- School of Mechanical Engineering, Beijing Institute of Technology, No. 5 Zhongguancun South Street, Haidian District, Beijing 100081, China; (L.W.); (S.P.)
| | - Li Jiao
- Key Laboratory of Fundamental Science for Advanced Machining Beijing Institute of Technology, No. 5 Zhongguancun South Street, Haidian District, Beijing 100081, China; (L.J.); (P.Y.); (X.W.)
| | - Shuoshuo Pang
- School of Mechanical Engineering, Beijing Institute of Technology, No. 5 Zhongguancun South Street, Haidian District, Beijing 100081, China; (L.W.); (S.P.)
| | - Pei Yan
- Key Laboratory of Fundamental Science for Advanced Machining Beijing Institute of Technology, No. 5 Zhongguancun South Street, Haidian District, Beijing 100081, China; (L.J.); (P.Y.); (X.W.)
| | - Xibin Wang
- Key Laboratory of Fundamental Science for Advanced Machining Beijing Institute of Technology, No. 5 Zhongguancun South Street, Haidian District, Beijing 100081, China; (L.J.); (P.Y.); (X.W.)
| | - Tianyang Qiu
- Key Laboratory of Fundamental Science for Advanced Machining Beijing Institute of Technology, No. 5 Zhongguancun South Street, Haidian District, Beijing 100081, China; (L.J.); (P.Y.); (X.W.)
- Correspondence:
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3
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Yeazel TR, Becker ML. Advancing Toward 3D Printing of Bioresorbable Shape Memory Polymer Stents. Biomacromolecules 2020; 21:3957-3965. [PMID: 32924443 DOI: 10.1021/acs.biomac.0c01082] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Stents have evolved significantly since their introduction to the medical field in the early 1980s, becoming widely used in percutaneous coronary interventions and following nephrological procedures. However, the current commercially available stents do not degrade and remain in the body forever, leading to problems like restenosis in cardiovascular applications or requiring removal procedures in ureteral applications. Efforts to replace metal with resorbable materials have largely been halted after the commercial failure of and safety concerns elicited by Abbott's Absorb stent in 2017. Industry continues to use common polymers such as poly(l-lactide) (PLLA) and polycaprolactone (PCL) for biomedical products, but due to the weak mechanical properties of these bioresorbable materials in comparison to metals, these devices have struggled to accomplish the goals set, increasing risk of thrombosis. 3D printing stents using bioresorbable and shape memory materials could provide a method of patient-personalized production, remove the need for balloon expansion, and limit stent migration, thus bringing a new age of stent technology. The investigation of a range of 3D-printable and bioresorbable shape-memory polymers can provide solutions to the shortcomings of previously explored bioresorbable stents and revitalize the medical device industry efforts into advancing stent technology.
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Affiliation(s)
- Taylor R Yeazel
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, North Carolina 27708, United States
| | - Matthew L Becker
- Department of Mechanical Engineering and Materials Science, Duke University, Durham, North Carolina 27708, United States.,Departments of Chemistry, Biomedical Engineering, Orthopaedic Surgery, Duke University, Durham, North Carolina 27708, United States
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Budak K, Sogut O, Aydemir Sezer U. A review on synthesis and biomedical applications of polyglycolic acid. JOURNAL OF POLYMER RESEARCH 2020. [DOI: 10.1007/s10965-020-02187-1] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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5
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Hajebi S, Mohammadi Nasr SA, Rabiee N, Bagherzadeh M, Ahmadi S, Rabiee M, Tahriri M, Tayebi L, Hamblin MR. Bioresorbable composite polymeric materials for tissue engineering applications. INT J POLYM MATER PO 2020. [DOI: 10.1080/00914037.2020.1765365] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- Sakineh Hajebi
- Department of Polymer Engineering, Sahand University of Technology, Tabriz, Iran
- Institute of Polymeric Materials, Sahand University of Technology, Tabriz, Iran
| | | | - Navid Rabiee
- Department of Chemistry, Sharif University of Technology, Tehran, Iran
| | | | - Sepideh Ahmadi
- Student Research Committee, Department of Biotechnology, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
- Cellular and Molecular Biology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad Rabiee
- Biomaterials Group, Department of Biomedical Engineering, Amirkabir University of Technology, Tehran, Iran
| | | | - Lobat Tayebi
- Marquette University School of Dentistry, Milwaukee, WI, USA
| | - Michael R. Hamblin
- Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, MA, USA
- Department of Dermatology, Harvard Medical School, Boston, MA, USA
- Laser Research Centre, Faculty of Health Science, University of Johannesburg, Johannesburg, South Africa
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Ahmed KK, Tamer MA, Ghareeb MM, Salem AK. Recent Advances in Polymeric Implants. AAPS PharmSciTech 2019; 20:300. [PMID: 31482251 DOI: 10.1208/s12249-019-1510-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 08/12/2019] [Indexed: 12/17/2022] Open
Abstract
Implantable drug delivery systems, such as drug pumps and polymeric drug depots, have emerged as means of providing predetermined drug release profiles at the desired site of action. While initial implants aimed at providing an enduring drug supply, developments in polymer chemistry and pharmaceutical technology and the growing need for refined drug delivery patterns have prompted the design of sophisticated drug delivery implants such as on-demand drug-eluting implants and personalized 3D printed implants. The types of cargo loaded into these implants range from small drug molecules to hormones and even therapeutic cells. This review will shed light upon recent advances in materials and composites used for polymeric implant fabrication, highlight select approaches employed in polymeric implant fabrication, feature medical applications where polymeric implants have a significant impact, and report recent advances made in these areas.
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Cha GD, Kang D, Lee J, Kim D. Bioresorbable Electronic Implants: History, Materials, Fabrication, Devices, and Clinical Applications. Adv Healthc Mater 2019; 8:e1801660. [PMID: 30957984 DOI: 10.1002/adhm.201801660] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2018] [Revised: 02/14/2019] [Indexed: 12/13/2022]
Abstract
Medical implants, either passive implants for structural support or implantable devices with active electronics, have been widely used for the diagnosis and treatment of various diseases and clinical issues. These implants offer various functions, including mechanical support of biological structures in orthopedic and dental applications, continuous electrophysiological monitoring and feedback of electrical stimulation in neuronal and cardiac applications, and controlled drug delivery while maintaining arterial structure in drug-eluting stents. Although these implants exhibit long-term biocompatibility, surgery for their retrieval is often required, which imposes physical, biological, and economical burdens on the patients. Therefore, as an alternative to such secondary surgeries, bioresorbable implants that disappear after a certain period of time inside the body, including bioresorbable active electronics, have been highlighted recently. This review first discusses the historical background of medical implants and briefly define related terminology. Representative examples of non-degradable medical implants for passive structural support and/or for diagnosis and therapy with active electronics are also provided. Then, recent progress in bioresorbable active implants composed of biosignal sensors, actuators for therapeutics, wireless power supply components, and their integrated systems are reviewed. Finally, clinical applications of these bioresorbable electronic implants are exemplified with brief conclusion and future outlook.
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Affiliation(s)
- Gi Doo Cha
- Center for Nanoparticle ResearchInstitute for Basic Science (IBS) Seoul 08826 Republic of Korea
- School of Chemical and Biological EngineeringInstitute of Chemical ProcessesSeoul National University (SNU) Seoul 08826 Republic of Korea
| | - Dayoung Kang
- Center for Nanoparticle ResearchInstitute for Basic Science (IBS) Seoul 08826 Republic of Korea
- School of Chemical and Biological EngineeringInstitute of Chemical ProcessesSeoul National University (SNU) Seoul 08826 Republic of Korea
| | - Jongha Lee
- Center for Nanoparticle ResearchInstitute for Basic Science (IBS) Seoul 08826 Republic of Korea
- School of Chemical and Biological EngineeringInstitute of Chemical ProcessesSeoul National University (SNU) Seoul 08826 Republic of Korea
| | - Dae‐Hyeong Kim
- Center for Nanoparticle ResearchInstitute for Basic Science (IBS) Seoul 08826 Republic of Korea
- School of Chemical and Biological EngineeringInstitute of Chemical ProcessesSeoul National University (SNU) Seoul 08826 Republic of Korea
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Biodegradable stents for coronary artery disease treatment: Recent advances and future perspectives. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2018; 91:163-178. [DOI: 10.1016/j.msec.2018.04.100] [Citation(s) in RCA: 84] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2017] [Revised: 04/11/2018] [Accepted: 04/28/2018] [Indexed: 12/24/2022]
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9
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Wang YJ, Jeng US, Hsu SH. Biodegradable Water-Based Polyurethane Shape Memory Elastomers for Bone Tissue Engineering. ACS Biomater Sci Eng 2018; 4:1397-1406. [DOI: 10.1021/acsbiomaterials.8b00091] [Citation(s) in RCA: 83] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Yu-Jen Wang
- Institute of Polymer Science and Engineering, National Taiwan University, No. 1 Sec. 4 Roosevelt Road, Taipei 10617, Taiwan, R.O.C
| | - U-Ser Jeng
- National Synchrotron Radiation Research Center, Hsinchu Science Park, No. 101 Hsin-Ann Road, Hsinchu 30076, Taiwan, R.O.C
| | - Shan-hui Hsu
- Institute of Polymer Science and Engineering, National Taiwan University, No. 1 Sec. 4 Roosevelt Road, Taipei 10617, Taiwan, R.O.C
- Research and Development Center for Medical Devices, National Taiwan University, No. 1 Sec. 4 Roosevelt Road, Taipei 10617, Taiwan, R.O.C
- Institute of Cellular and System Medicine, National Health Research Institutes, No. 35 Keyan Road, Miaoli 35053, Taiwan, R.O.C
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10
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Recent developments in drug eluting devices with tailored interfacial properties. Adv Colloid Interface Sci 2017; 249:181-191. [PMID: 28532663 DOI: 10.1016/j.cis.2017.05.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Revised: 05/02/2017] [Accepted: 05/02/2017] [Indexed: 11/23/2022]
Abstract
Drug eluting devices have greatly evolved during past years to become fundamental products of great marketing importance in the biomedical field. There is currently a large diversity of highly specialized devices for specific applications, making the development of these devices an exciting field of research. The replacement of the former bare metal devices by devices loaded with drugs allowed the sustained and controlled release of drugs, to achieve the desired local therapeutic concentration of drug. The newer devices have been "engineered" with surfaces containing micro- and nanoscale features in a well-controlled manner, that have shown to significantly affect cellular and subcellular function of various biological systems. For example, the topography can be structured to form an antifouling surface mimicking the defense mechanisms found in nature, like the skin of the shark. In the case of bone implants, well-controlled nanostructured interfaces can promote osteoblast differentiation and matrix production, and enhance short-term and long-term osteointegration. In any case, the goal of current research is to design implants that induce controlled, guided, and rapid healing. This article reviews recent trends in the development of drug eluting devices, as well as recent developments on the micro/nanotechnology scales, and their future challenges. For this purpose medical devices have been divided according to the different systems of the body they are focused to: orthopedic devices, breathing stents, gastrointestinal and urinary systems, devices for cardiovascular diseases, neuronal implants, and wound dressings.
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Kandzari DE, Mauri L, Koolen JJ, Massaro JM, Doros G, Garcia-Garcia HM, Bennett J, Roguin A, Gharib EG, Cutlip DE, Waksman R. Ultrathin, bioresorbable polymer sirolimus-eluting stents versus thin, durable polymer everolimus-eluting stents in patients undergoing coronary revascularisation (BIOFLOW V): a randomised trial. Lancet 2017; 390:1843-1852. [PMID: 28851504 DOI: 10.1016/s0140-6736(17)32249-3] [Citation(s) in RCA: 201] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Revised: 08/04/2017] [Accepted: 08/07/2017] [Indexed: 01/14/2023]
Abstract
BACKGROUND The development of coronary drug-eluting stents has included use of new metal alloys, changes in stent architecture, and use of bioresorbable polymers. Whether these advancements improve clinical safety and efficacy has not been shown in previous randomised trials. We aimed to examine the clinical outcomes of a bioresorbable polymer sirolimus-eluting stent compared with a durable polymer everolimus-eluting stent in a broad patient population undergoing percutaneous coronary intervention. METHODS BIOFLOW V was an international, randomised trial done in patients undergoing elective and urgent percutaneous coronary intervention in 90 hospitals in 13 countries (Australia, Belgium, Canada, Denmark, Germany, Hungary, Israel, the Netherlands, New Zealand, South Korea, Spain, Switzerland, and the USA). Eligible patients were those aged 18 years or older with ischaemic heart disease undergoing planned stent implantation in de-novo, native coronary lesions. Patients were randomly assigned (2:1) to either an ultrathin strut (60 μm) bioresorbable polymer sirolimus-eluting stent or to a durable polymer everolimus-eluting stent. Randomisation was via a central web-based data capture system (mixed blocks of 3 and 6), and stratified by study site. The primary endpoint was 12-month target lesion failure. The primary non-inferiority comparison combined these data from two additional randomised trials of bioresorbable polymer sirolimus-eluting stent and durable polymer everolimus-eluting stent with Bayesian methods. Analysis was by intention to treat. The trial is registered with ClinicalTrials.gov, number NCT02389946. FINDINGS Between May 8, 2015, and March 31, 2016, 4772 patients were recruited into the study. 1334 patients met inclusion criteria and were randomly assigned to treatment with bioresorbable polymer sirolimus-eluting stents (n=884) or durable polymer everolimus-eluting stents (n=450). 52 (6%) of 883 patients in the bioresorbable polymer sirolimus-eluting stent group and 41 (10%) of 427 patients in the durable polymer everolimus-eluting stent group met the 12-month primary endpoint of target lesion failure (95% CI -6·84 to -0·29, p=0·0399), with differences in target vessel myocardial infarction (39 [5%] of 831 patients vs 35 [8%] of 424 patients, p=0·0155). The posterior probability that the bioresorbable polymer sirolimus-eluting stent is non-inferior to the durable polymer everolimus-eluting stent was 100% (Bayesian analysis, difference in target lesion failure frequency -2·6% [95% credible interval -5·5 to 0·1], non-inferiority margin 3·85%, n=2208). INTERPRETATION The outperformance of the ultrathin, bioresorbable polymer sirolimus-eluting stent over the durable polymer everolimus-eluting stent in a complex patient population undergoing percutaneous coronary intervention suggests a new direction in improving next generation drug-eluting stent technology. FUNDING BIOTRONIK.
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Affiliation(s)
| | - Laura Mauri
- Divison of Cardiovascular Medicine, Brigham and Women's Hospital, Boston, MA, USA
| | | | - Joseph M Massaro
- Department of Biostatistics and Epidemiology, Boston University School of Public Health, Boston, MA, USA
| | - Gheorghe Doros
- Department of Biostatistics and Epidemiology, Boston University School of Public Health, Boston, MA, USA; Baim Institute for Clinical Research, Boston, MA, USA
| | - Hector M Garcia-Garcia
- Division of Interventional Cardiology, MedStar Cardiovascular Research Network, MedStar Washington Hospital Center, Washington, DC, USA
| | - Johan Bennett
- Department of Cardiovascular Medicine, University Hospitals Leuven, Leuven, Belgium
| | - Ariel Roguin
- Department of Cardiology, Rambam Medical Center, Haifa, Israel
| | | | - Donald E Cutlip
- Beth Israel Deaconess Medical Center, Baim Institute for Clinical Research, Boston, MA, USA
| | - Ron Waksman
- Division of Interventional Cardiology, MedStar Cardiovascular Research Network, MedStar Washington Hospital Center, Washington, DC, USA
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Ware HOT, Farsheed AC, Baker E, Ameer G, Sun C. Fabrication Speed Optimization for High-resolution 3D-printing of Bioresorbable Vascular Scaffolds. ACTA ACUST UNITED AC 2017. [DOI: 10.1016/j.procir.2017.04.038] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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13
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He Y, Tuck CJ, Prina E, Kilsby S, Christie SDR, Edmondson S, Hague RJM, Rose FRAJ, Wildman RD. A new photocrosslinkable polycaprolactone-based ink for three-dimensional inkjet printing. J Biomed Mater Res B Appl Biomater 2016; 105:1645-1657. [PMID: 27177716 DOI: 10.1002/jbm.b.33699] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Revised: 04/08/2016] [Accepted: 04/14/2016] [Indexed: 11/09/2022]
Abstract
A new type of photocrosslinkable polycaprolactone (PCL) based ink that is suitable for three-dimensional (3D) inkjet printing has been developed. Photocrosslinkable Polycaprolactone dimethylacrylate (PCLDMA) was synthesized and mixed with poly(ethylene glycol) diacrylate (PEGDA) to prepare an ink with a suitable viscosity for inkjet printing. The ink performance under different printing environments, initiator concentrations, and post processes was studied. This showed that a nitrogen atmosphere during printing was beneficial for curing and material property optimization, as well as improving the quality of structures produced. A simple structure, built in the z-direction, demonstrated the potential for this material for the production of 3D printed objects. Cell tests were carried out to investigate the biocompatibility of the developed ink. © 2016 The Authors Journal of Biomedical Materials Research Part B: Applied Biomaterials Published by Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 1645-1657, 2017.
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Affiliation(s)
- Yinfeng He
- Faculty of Engineering, University of Nottingham, Nottingham, UK
| | | | - Elisabetta Prina
- School of Pharmacy, Centre for Biomolecular Sciences, University of Nottingham, Nottingham, UK
| | - Sam Kilsby
- Department of Chemistry, Loughborough University, Loughborough, UK
| | | | | | | | - Felicity R A J Rose
- School of Pharmacy, Centre for Biomolecular Sciences, University of Nottingham, Nottingham, UK
| | - Ricky D Wildman
- Faculty of Engineering, University of Nottingham, Nottingham, UK
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Chan BQY, Low ZWK, Heng SJW, Chan SY, Owh C, Loh XJ. Recent Advances in Shape Memory Soft Materials for Biomedical Applications. ACS APPLIED MATERIALS & INTERFACES 2016; 8:10070-10087. [PMID: 27018814 DOI: 10.1021/acsami.6b01295] [Citation(s) in RCA: 176] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Shape memory polymers (SMPs) are smart and adaptive materials able to recover their shape through an external stimulus. This functionality, combined with the good biocompatibility of polymers, has garnered much interest for biomedical applications. In this review, we discuss the design considerations critical to the successful integration of SMPs for use in vivo. We also highlight recent work on three classes of SMPs: shape memory polymers and blends, shape memory polymer composites, and shape memory hydrogels. These developments open the possibility of incorporating SMPs into device design, which can lead to vast technological improvements in the biomedical field.
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Affiliation(s)
- Benjamin Qi Yu Chan
- Institute of Materials Research and Engineering (IMRE) , 2 Fusionopolis Way, #08-03 Innovis, Singapore 138634, Singapore
- Department of Materials Science and Engineering, National University of Singapore , 9 Engineering Drive 1, Singapore 117576, Singapore
| | - Zhi Wei Kenny Low
- Institute of Materials Research and Engineering (IMRE) , 2 Fusionopolis Way, #08-03 Innovis, Singapore 138634, Singapore
- Department of Materials Science and Engineering, National University of Singapore , 9 Engineering Drive 1, Singapore 117576, Singapore
| | - Sylvester Jun Wen Heng
- Institute of Materials Research and Engineering (IMRE) , 2 Fusionopolis Way, #08-03 Innovis, Singapore 138634, Singapore
- Department of Materials Science and Engineering, National University of Singapore , 9 Engineering Drive 1, Singapore 117576, Singapore
| | - Siew Yin Chan
- Institute of Materials Research and Engineering (IMRE) , 2 Fusionopolis Way, #08-03 Innovis, Singapore 138634, Singapore
- School of Science, Monash University Malaysia , Bandar Sunway, 47500 Selangor Darul Ehsan, Malaysia
| | - Cally Owh
- Institute of Materials Research and Engineering (IMRE) , 2 Fusionopolis Way, #08-03 Innovis, Singapore 138634, Singapore
| | - Xian Jun Loh
- Institute of Materials Research and Engineering (IMRE) , 2 Fusionopolis Way, #08-03 Innovis, Singapore 138634, Singapore
- Department of Materials Science and Engineering, National University of Singapore , 9 Engineering Drive 1, Singapore 117576, Singapore
- Singapore Eye Research Institute , 11 Third Hospital Avenue, Singapore 168751, Singapore
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15
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He Y, Wildman RD, Tuck CJ, Christie SDR, Edmondson S. An Investigation of the Behavior of Solvent based Polycaprolactone ink for Material Jetting. Sci Rep 2016; 6:20852. [PMID: 26868530 PMCID: PMC4751626 DOI: 10.1038/srep20852] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Accepted: 01/12/2016] [Indexed: 11/09/2022] Open
Abstract
An initial study of processing bioresorbable polycaprolactone (PCL) through material jetting was conducted using a Fujifilm Dimatix DMP-2830 material printer. The aim of this work was to investigate a potential solvent based method of jetting polycaprolactone. Several solvents were used to prepare a PCL solvent based ink and 1, 4-dioxane was chosen with the consideration of both solubility and safety. The morphology of PCL formed under different substrate temperatures, droplet spacings were investigated. Multi-layer PCL structures were printed and characterized. This work shows that biodegradable polycaprolactone can be processed through material jetting.
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Affiliation(s)
- Yinfeng He
- Additive Manufacturing and 3D Printing Research Group, University of Nottingham, Nottingham, NG9 2RD, UK
| | - Ricky D. Wildman
- Additive Manufacturing and 3D Printing Research Group, University of Nottingham, Nottingham, NG9 2RD, UK
| | - Chris J. Tuck
- Additive Manufacturing and 3D Printing Research Group, University of Nottingham, Nottingham, NG9 2RD, UK
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Ratnakar A, Hari Prasad K, Vivekananthan S, Karthika PC, Kumar A. Synthesis and characterization of Polyurethane – Titanium Dioxide – Hydroxyapatite nanocomposite for biomedical applications. ACTA ACUST UNITED AC 2016. [DOI: 10.1016/j.matpr.2016.11.072] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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17
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Roopmani P, Sethuraman S, Satheesh S, Maheswari Krishnan U. The metamorphosis of vascular stents: passive structures to smart devices. RSC Adv 2016. [DOI: 10.1039/c5ra19109b] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
The role of nanotechnology enabled techniques in the evolution of vascular stents.
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Affiliation(s)
- Purandhi Roopmani
- Centre for Nanotechnology and Advanced Biomaterials (CeNTAB)
- School of Chemical and Biotechnology
- SASTRA University
- Thanjavur-613 401
- India
| | - Swaminathan Sethuraman
- Centre for Nanotechnology and Advanced Biomaterials (CeNTAB)
- School of Chemical and Biotechnology
- SASTRA University
- Thanjavur-613 401
- India
| | - Santhosh Satheesh
- Jawaharlal Institute of Post Graduate Medical Education and Research (JIPMER)
- Department of Cardiology
- Pondicherry-605 006
- India
| | - Uma Maheswari Krishnan
- Centre for Nanotechnology and Advanced Biomaterials (CeNTAB)
- School of Chemical and Biotechnology
- SASTRA University
- Thanjavur-613 401
- India
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Chan BQY, Liow SS, Loh XJ. Organic–inorganic shape memory thermoplastic polyurethane based on polycaprolactone and polydimethylsiloxane. RSC Adv 2016. [DOI: 10.1039/c6ra04041a] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
We report an organic–inorganic SMP comprising PCL and PDMS that exhibits extremely fast-response time at body temperature and thermoplasticity that allows for solvent processing. The SMP recovered to the programmed shape in less than 0.5 seconds.
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Affiliation(s)
- Benjamin Qi Yu Chan
- Institute of Materials Research and Engineering (IMRE)
- Agency for Science
- Technology and Research (A*STAR)
- Singapore 138634
- Singapore
| | - Sing Shy Liow
- Institute of Materials Research and Engineering (IMRE)
- Agency for Science
- Technology and Research (A*STAR)
- Singapore 138634
- Singapore
| | - Xian Jun Loh
- Institute of Materials Research and Engineering (IMRE)
- Agency for Science
- Technology and Research (A*STAR)
- Singapore 138634
- Singapore
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19
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Kimble LD, Bhattacharyya D. In VitroDegradation Effects on Strength, Stiffness, and Creep of PLLA/PBS: A Potential Stent Material. INT J POLYM MATER PO 2014. [DOI: 10.1080/00914037.2014.945203] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Abstract
Edible polymers have established substantial deliberation in modern eons because of their benefits comprising use as edible materials over synthetic polymers. This could contribute to the reduction of environmental contamination. Edible polymers can practically diminish the complexity and thus improve the recyclability of materials, compared to the more traditional non-environmentally friendly materials and may be able to substitute such synthetic polymers. A synthetic hydrogel polymer unlocked a new possibility for development of films, coatings, extrudable pellets, and synthetic nanopolymers, particularly designed for medical, agricultural, and industrial fields. Edible polymers offer many advantages for delivering drugs and tissue engineering. Edible polymer technology helps food industries to make their products more attractive and safe to use. Novel edible materials have been derived from many natural sources that have conventionally been regarded as discarded materials. The objective of this review is to provide a comprehensive introduction to edible polymers by providing descriptions in terms of their origin, properties, and potential uses.
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Sgarioto M, Adhikari R, Gunatillake PA, Moore T, Malherbe F, Nagel MD, Patterson J. Properties andin vitroevaluation of high modulus biodegradable polyurethanes for applications in cardiovascular stents. J Biomed Mater Res B Appl Biomater 2014; 102:1711-9. [DOI: 10.1002/jbm.b.33137] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Revised: 01/16/2014] [Accepted: 02/25/2014] [Indexed: 11/07/2022]
Affiliation(s)
- Melissa Sgarioto
- Swinburne University of Technology; Faculty of Life and Social Sciences; Hawthorn, Victoria 3122 Australia
- Université de Technologie de Compiègne, UMR CNRS 7338 Biomécanique et Bioingénierie, Centre de Recherches de Royallieu; Compiègne Cedex France
| | - Raju Adhikari
- CSIRO Materials Science and Engineering, Clayton South MDC; Victoria 3169 Australia
| | | | - Tim Moore
- PolyNovo Biomaterials Pty Ltd, Port Melbourne; Victoria 3207 Australia
| | - François Malherbe
- Swinburne University of Technology; Faculty of Life and Social Sciences; Hawthorn, Victoria 3122 Australia
| | - Marie-Danielle Nagel
- Université de Technologie de Compiègne, UMR CNRS 7338 Biomécanique et Bioingénierie, Centre de Recherches de Royallieu; Compiègne Cedex France
| | - John Patterson
- Swinburne University of Technology; Faculty of Life and Social Sciences; Hawthorn, Victoria 3122 Australia
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22
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Shellock FG, Giangarra CJ. In vitro assessment of 3-T MRI issues for a bioabsorbable, coronary artery scaffold with metallic markers. Magn Reson Imaging 2014; 32:163-7. [DOI: 10.1016/j.mri.2013.10.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Revised: 07/22/2013] [Accepted: 10/10/2013] [Indexed: 10/26/2022]
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23
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Nederberg F, Watanabe J, Ishihara K, Hilborn J, Bowden T. Biocompatible and biodegradable phosphorylcholine ionomers with reduced protein adsorption and cell adhesion. JOURNAL OF BIOMATERIALS SCIENCE-POLYMER EDITION 2012; 17:605-14. [PMID: 16892723 DOI: 10.1163/156856206777346304] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
In this paper a recently developed biodegradable phosphorylcholine ionomer (PC ionomer) was evaluated in different biological environments with a focus on the adsorption of proteins (fibrinogen) and the adhesion of cells. Our results have shown that the polar phosphoryl choline (PC) group may be enriched at the surface of cast films with an added hydrophilic environment. X-ray photoelectron spectroscopy confirmed the surface depletion of PC groups in dry conditions, as nitrogen and phosphorous atoms were found in the bulk of the material but not at the outermost surface layer. The surface enrichment leads to a strongly hydrophilic surface that prevents the adsorption of proteins and reduces the adhesion of cells. The non-functional and hydrophobic reference poly(trimethylene carbonate) (PTMC) adsorbs both proteins and cells, thus the wetting and low adhesion behavior of the PC ionomer can be attributed to the introduced PC functionality. Since the in vivo acceptance of biomaterials is determined by their ability to withstand protein adsorption the PC ionomer described in this paper is highly interesting for a number of in vivo applications in which the adsorption of proteins may be critical, for example, blood contact events.
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Affiliation(s)
- Fredrik Nederberg
- Department of Materials Chemistry, Polymer Chemistry, Box 538, Uppsala University, S-751 21 Uppsala, Sweden
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24
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Griffiths EA, Gregory CJ, Pursnani KG, Ward JB, Stockwell RC. The use of biodegradable (SX-ELLA) oesophageal stents to treat dysphagia due to benign and malignant oesophageal disease. Surg Endosc 2012; 26:2367-75. [PMID: 22395954 DOI: 10.1007/s00464-012-2192-9] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2011] [Accepted: 01/23/2012] [Indexed: 12/18/2022]
Abstract
BACKGROUND Biodegradable (BD) oesophageal stents have been available commercially only since 2008 and previous published research is limited. Our aim was to review the use of BD stents to treat dysphagia in benign or malignant oesophageal strictures. METHODS Patients were identified from a prospective interventional radiological database. BD stents were inserted radiologically under fluoroscopic control. RESULTS Between July 2008 and February 2011, 25 attempts at placing SX-ELLA biodegradable oesophageal stents were made in 17 males and five females, with a median age of 69 (range = 54-80) years. Two patients required more than one BD stent. Indications were benign strictures (n = 7) and oesophageal cancer (n = 17). One attempt was unsuccessful for a technical success rate of 96% with no immediate complications. Clinical success rate was 76%. Median dysphagia score before stent insertion was 3 (range = 2-4) compared to 2 (range = 0-3) after stent insertion (p = 0.0001). CONCLUSION BD stents provide good dysphagia relief for the life time of the stent. They may help avoid the use of feeding tubes in patients having radical chemoradiotherapy or awaiting oesophagectomy. They do not require removal or interfere with radiotherapy planning via imaging. However, the reintervention rate is high after the stent dissolves.
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Affiliation(s)
- Ewen A Griffiths
- Department of Upper Gastrointestinal Surgery, Lancashire Teaching Hospitals, NHS Foundation Trust, Royal Preston Hospital, Sharoe Green Lane, Fulwood, Preston, PR2 9HT, UK.
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Huynh L, Neale C, Pomès R, Allen C. Computational approaches to the rational design of nanoemulsions, polymeric micelles, and dendrimers for drug delivery. NANOMEDICINE-NANOTECHNOLOGY BIOLOGY AND MEDICINE 2012; 8:20-36. [DOI: 10.1016/j.nano.2011.05.006] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2011] [Revised: 05/09/2011] [Accepted: 05/14/2011] [Indexed: 12/20/2022]
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Li J, Chen C, Wang X, Gu Z, Chen B. Novel Strategy to Fabricate PLA/Au Nanocomposites as an Efficient Drug Carrier for Human Leukemia Cells in Vitro. NANOSCALE RESEARCH LETTERS 2011; 6:29. [PMID: 27502652 PMCID: PMC3211355 DOI: 10.1007/s11671-010-9762-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2010] [Accepted: 08/14/2010] [Indexed: 05/24/2023]
Abstract
Poly (lactic acid) (PLA) polymer has the promising applications in the biomedical field because of its biodegradability and safe elimination. In this study, we have explored the bio-application of new nanocomposites composed with PLA nanofibers and Au nanoparticles as the potential drug carrier for an efficient drug delivery in target cancer cells. The results demonstrated that the anticancer drug daunorubicin could be efficiently self-assembled on the surface of PLA/Au nanocomposites and the synergistic enhancement of PLA/Au nanocomposites conjugated with daunorubicin into drug-sensitive K562 and drug-resistant leukemia K562/AO2 cells could be obviously observed by MTT assay and confocal fluorescence microscopy studies. These observations suggest that the new nanocomposites could readily induce daunorubicin to accumulate and uptake in target leukemia cells and increase the drug's cytotoxicity. Especially, the PLA/Au nanocomposites could significantly facilitate the cellular drug absorbtion of daunorubicin into drug-resistant K562/AO2 cells and efficiently inhibit the cancer cell proliferation. This raised the possibility to utilize the PLA/Au nanocomposites as a new effective additive agent to inhibit the drug resistance and thus as a novel strategy to sensitively track the respective cancer cells.
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Affiliation(s)
- Jingyuan Li
- State Key Lab of Bioelectronics (Chien-Shiung WU Laboratory), Southeast University, 210096, Nanjing, China
| | - Chen Chen
- State Key Lab of Bioelectronics (Chien-Shiung WU Laboratory), Southeast University, 210096, Nanjing, China
| | - Xuemei Wang
- State Key Lab of Bioelectronics (Chien-Shiung WU Laboratory), Southeast University, 210096, Nanjing, China.
| | - Zhongze Gu
- State Key Lab of Bioelectronics (Chien-Shiung WU Laboratory), Southeast University, 210096, Nanjing, China
| | - Baoan Chen
- Department of Hematology, Zhongda Hospital, Southeast University, 210096, Nanjing, China
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27
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Park CG, Kim MH, Park M, Lee JE, Lee SH, Park JH, Yoon KH, Bin Choy Y. Polymeric nanofiber coated esophageal stent for sustained delivery of an anticancer drug. Macromol Res 2011. [DOI: 10.1007/s13233-011-1112-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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28
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Reddy PP, Defoor WR. Ureteroscopy: The standard of care in the management of upper tract urolithiasis in children. Indian J Urol 2011; 26:555-63. [PMID: 21369390 PMCID: PMC3034066 DOI: 10.4103/0970-1591.74459] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Objectives Advances in technology and the continued evolution in the design of ureteroscopes now permit a primary endoscopic approach to the upper urinary tract of pediatric patients on a routine basis to treat a diverse group of conditions that include urolithiasis, hematuria and strictures. The purpose of this review article is to demonstrate that ureteroscopic lithotripsy is now to be considered the standard of care in the management of upper tract urolithiasis in the pediatric patient, replacing shockwave lithotripsy (ESWL) as the first line of therapy. Additionally, the article will discuss the available endoscopic equipment and the lessons learned over the years to optimize the success of these procedures in children. Materials and Methods A systematic review of articles written about ureteroscopy (URS) in the contemporary urological literature (1990-2009) on PubMed was undertaken. The success rates and complications of pediatric ureteroscopic procedures were abstracted from the identified publications and the results were tabulated and compared with the success rates of shockwave lithotripsy. Results In over 832 URS cases, there was a 5.9% complication rate and a stone-free rate of 93.4%. The stone-free rates of URS are superior to those obtained with the published success rates with ESWL of 80.3% in 1,839 cases. Conclusions The safety and outcomes of ureteroscopic lithotripsy in the management of pediatric urolithiasis now justify that this treatment modality be considered the standard of care and first line of therapy in the management of children who present with upper tract stones.
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Affiliation(s)
- Pramod P Reddy
- Surgical Services, Division of Pediatric Urology. Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
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29
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Lei L, Guo SR, Chen WL, Rong HJ, Lu F. Stents as a platform for drug delivery. Expert Opin Drug Deliv 2011; 8:813-31. [DOI: 10.1517/17425247.2011.572068] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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30
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Liu SJ, Chiang FJ, Hsiao CY, Kau YC, Liu KS. Fabrication of Balloon-Expandable Self-Lock Drug-Eluting Polycaprolactone Stents Using Micro-Injection Molding and Spray Coating Techniques. Ann Biomed Eng 2010; 38:3185-94. [DOI: 10.1007/s10439-010-0075-6] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2010] [Accepted: 05/11/2010] [Indexed: 10/19/2022]
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31
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You Q, Wang F, Duan L, Du X, Xiao M, Shen Z. Construction of Small-Caliber, Polydiaxanone Cyclohexanone Vascular Stents. Cell Biochem Biophys 2010; 57:35-43. [DOI: 10.1007/s12013-010-9081-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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32
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Hyun Kim J, Jin Kang T, Yu WR. Simulation of mechanical behavior of temperature-responsive braided stents made of shape memory polyurethanes. J Biomech 2010; 43:632-43. [DOI: 10.1016/j.jbiomech.2009.10.032] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2009] [Revised: 09/17/2009] [Accepted: 10/15/2009] [Indexed: 10/20/2022]
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33
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Bakhshi R, Edirisinghe M, Darbyshire A, Ahmad Z, Seifalian A. Electrohydrodynamic Jetting Behaviour of Polyhedral Oligomeric Silsesquioxane Nanocomposite. J Biomater Appl 2008; 23:293-309. [DOI: 10.1177/0885328208089125] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In this paper, we investigate in detail the electrohydrodynamic spraying of a nonbiodegradable nanocomposite polyhedral oligomeric silsesquioxane polymer developed in our laboratories and currently being explored for coating metallic stent materials. Different concentrations of the polymer have been dissolved to prepare, characterise, and electrohydrodynamically deposit the polymer on stainless steel. From the experiments, the solution containing 15 wt% polymer was selected for further investigation. The variation of film/ coating thickness as a function of spraying time was studied and the structural features of the film were assessed using microscopy. Films were also tensile tested. This study has identified a process and conditions which can be used in our stent coating research.
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Affiliation(s)
- R. Bakhshi
- Department of Mechanical Engineering, University College London Torrington Place, London WC1E 7JE, UK, Biomaterials and Tissue Engineering Centre, Academic Division of Surgery and Interventional Sciences, University College London, Hampstead Campus London NW3 2PF, United Kingdom
| | - M.J. Edirisinghe
- Department of Mechanical Engineering, University College London Torrington Place, London WC1E 7JE, UK,
| | - A. Darbyshire
- Biomaterials and Tissue Engineering Centre, Academic Division of Surgery and Interventional Sciences, University College London, Hampstead Campus London NW3 2PF, United Kingdom
| | - Z. Ahmad
- Department of Mechanical Engineering, University College London Torrington Place, London WC1E 7JE, UK
| | - A.M. Seifalian
- Biomaterials and Tissue Engineering Centre, Academic Division of Surgery and Interventional Sciences, University College London, Hampstead Campus London NW3 2PF, United Kingdom
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Kraitzer A, Kloog Y, Zilberman M. Approaches for prevention of restenosis. J Biomed Mater Res B Appl Biomater 2008; 85:583-603. [PMID: 18098192 DOI: 10.1002/jbm.b.30974] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Coronary artery disease is characterized by a narrowing (stenosis) of the arteries that supply blood to the tissue of the heart. Continued restriction of blood flow manifests itself as angina and ultimately myocardial infarction (heart attack) for the patient. Heart bypass was once the only treatment for this condition, but over the years percutaneous coronary intervention (PCI) has become an increasingly attractive alternative to medical therapy and surgical revascularization for the treatment of coronary artery disease. A vascular stent is a medical device designed to serve as a temporary or permanent internal scaffold, to maintain or increase the lumen of a blood vessel. Metallic coronary stents were first introduced to prevent arterial dissections and to eliminate vessel recoil and intimal hyperplasia associated with PCI. Further advancement in the treatment of coronary artery disease is the development of drug-eluting stents that dramatically reduce the incidence of in-stent restenosis to less than 5%. Local drug delivery offers the advantages of allowing a relatively high local concentration of drug at the treatment site while minimizing systemic toxic effect. This review describes approaches for prevention of restenosis. It focuses on drugs for prevention of restenosis, bare metal stents, and drug-eluting stents. It also describes recent advances in bioresorbable stents. One of the chapters is dedicated to our novel composite bioresorbable drug-eluting fibers, designed to be used as basic elements in drug-eluting stents.
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Affiliation(s)
- Amir Kraitzer
- Department of Biomedical Engineering, Faculty of Engineering, Tel-Aviv University, Tel-Aviv 69978, Israel
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35
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Welch T, Eberhart RC, Chuong CJ. Characterizing the expansive deformation of a bioresorbable polymer fiber stent. Ann Biomed Eng 2008; 36:742-51. [PMID: 18264765 DOI: 10.1007/s10439-008-9455-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2007] [Accepted: 01/29/2008] [Indexed: 10/22/2022]
Abstract
Polymeric vascular stents must employ other strategies than malleable deformation, as generally practiced with metal stents, to expand and withstand compressive stresses in situ. The stent expansion strategy must further consider induced flow perturbations and wall stresses that may injure the vessel wall and promote thrombogenesis. Analyzing the stresses furled stents undergo during balloon-assisted expansion is an important first step in achieving a better understanding of stent-wall mechanical interactions, thereby to improve stent function. To this end, we performed finite element (FE) analysis of the balloon-induced unfurling of an internally coiled, bioresorbable polymeric stent employing a 3D FE solid model of a 120 degrees symmetric stent segment and a large deformation finite strain formulation. Uni-axial tensile testing of stent fiber elastic to plastic yielding provided the mechanical property information, and the von Mises criterion was employed to establish the elastic-plastic transition in the FE model. The model was validated with pressure and deformation measurements obtained during stent expansion tests. The internal coils of this inner coil-outer coil design twisted as the stent expanded, leading to plastic yielding at the point of tangency of the inner and outer coils. The remaining stent fiber portions underwent elastic bending. Cross-sections revealed only the outside surface layer of the coiled fiber underwent plastic yielding. The interior elastic fiber was supported by this plastic shell. The analysis suggests that during balloon-induced expansion, local plastic yielding in torsion "sets" the stent fibers, imparting high radial collapse resistance. The results further suggest that the stent exerts non-uniform mechanical forces on the vessel wall during expansion.
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Affiliation(s)
- Tre Welch
- Bioengineering Department, University of Texas at Arlington, Box 19138, Arlington, TX 76019, USA
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36
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Sharkawi T, Cornhill F, Lafont A, Sabaria P, Vert M. Intravascular bioresorbable polymeric stents: a potential alternative to current drug eluting metal stents. J Pharm Sci 2007; 96:2829-37. [PMID: 17979210 DOI: 10.1002/jps.20957] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Stent implantation following angioplasty is the standard treatment of coronary artery disease necessitating interventional procedures. The use of stents as a platform for local drug delivery is a popular strategy to achieve local pharmacological treatment to the diseased artery. Drug eluting stents (DES) are now largely preferred to bare metal stents when stent implantation is necessary. Lately, there have been several reports questioning the long-term safety of DES. An alternative to these drug eluting metal stents are bioresorbable polymeric stents (BPS) because of the many advantages of bioresorbable material. However, the fundamental differences in polymeric and metallic materials make the development of such an alternative a significant challenge. This review discusses the different advantages of BPS and the many constrains and requirements of such devices. An up to date commented review of published data concerning BPS is presented. Considerations are given on using BPS as local drug delivery systems as well as on evaluating BPS performances.
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Affiliation(s)
- Tahmer Sharkawi
- Artificial Biopolymer Research Center, UMR CNRS 5473, Faculty of Pharmacy, University of Montpellier 1, 15 av Charles Flahaut, 34093 Montpellier, Cedex, France.
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37
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Takahashi H, Letourneur D, Grainger DW. Delivery of large biopharmaceuticals from cardiovascular stents: a review. Biomacromolecules 2007; 8:3281-93. [PMID: 17929968 PMCID: PMC2606669 DOI: 10.1021/bm700540p] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
This review focuses on new and emerging large-molecule bioactive agents delivered from stent surfaces in drug-eluting stents (DESs) to inhibit vascular restenosis in the context of interventional cardiology. New therapeutic agents representing proteins, nucleic acids (small interfering RNAs and large DNA plasmids), viral delivery vectors, and even engineered cell therapies require specific delivery designs distinct from traditional smaller-molecule approaches on DESs. While small molecules are currently the clinical standard for coronary stenting, extension of the DESs to other lesion types, peripheral vasculature, and nonvasculature therapies will seek to deliver an increasingly sophisticated armada of drug types. This review describes many of the larger-molecule and biopharmaceutical approaches reported recently for stent-based delivery with the challenges associated with formulating and delivering these drug classes compared to the current small-molecule drugs. It also includes perspectives on possible future applications that may improve safety and efficacy and facilitate diversification of the DESs to other clinical applications.
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Affiliation(s)
- Hironobu Takahashi
- Department of Pharmaceutics and Pharmaceutical Chemistry, 30 South 2000 East, University of Utah, Salt Lake City, UT 84112-5280, USA
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Chen C, Lv G, Pan C, Song M, Wu C, Guo D, Wang X, Chen B, Gu Z. Poly(lactic acid) (PLA) based nanocomposites--a novel way of drug-releasing. Biomed Mater 2007; 2:L1-4. [PMID: 18458473 DOI: 10.1088/1748-6041/2/4/l01] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
In this communication, poly(lactic acid) nanofibers have been fabricated by electrospinning and then poly(lactic acid) (PLA) based nanocomposites have been prepared by accumulating anticancer drug daunorubicin on PLA nanofibers combined with TiO2 nanoparticles. Our atomic force microscopy (AFM) and laser-scanning confocal microscope (LSCM) studies demonstrate that the respective drug molecules could be readily self-assembled on the surface of the blends of nano-TiO2 with PLA polymer nanocomposites, which could further efficiently facilitate the drug permeation and accumulation on the target leukemia K562 cells. Besides, the respective new nanocomposites have good biocompatibility, ease of surface chemistry modification and very high surface area, which may afford the possibility for their promising application in pharmacology and biomedical engineering areas.
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Affiliation(s)
- Chen Chen
- State Key Lab of Bioelectronics (Chien-Shiung Wu Lab), Southeast University, Nanjing 210096, People's Republic of China
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Loos A, Rohde R, Haverich A, Barlach S. In Vitro and In Vivo Biocompatibility Testing of Absorbable Metal Stents. ACTA ACUST UNITED AC 2007. [DOI: 10.1002/masy.200750715] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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40
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Yakacki CM, Shandas R, Lanning C, Rech B, Eckstein A, Gall K. Unconstrained recovery characterization of shape-memory polymer networks for cardiovascular applications. Biomaterials 2007; 28:2255-63. [PMID: 17296222 PMCID: PMC2700024 DOI: 10.1016/j.biomaterials.2007.01.030] [Citation(s) in RCA: 380] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2006] [Accepted: 01/23/2007] [Indexed: 10/23/2022]
Abstract
Shape-memory materials have been proposed in biomedical device design due to their ability to facilitate minimally invasive surgery and recover to a predetermined shape in vivo. Use of the shape-memory effect in polymers is proposed for cardiovascular stent interventions to reduce the catheter size for delivery and offer highly controlled and tailored deployment at body temperature. Shape-memory polymer networks were synthesized via photopolymerization of tert-butyl acrylate and poly(ethylene glycol) dimethacrylate to provide precise control over the thermomechanical response of the system. The free recovery response of the polymer stents at body temperature was studied as a function of glass transition temperature (T(g)), crosslink density, geometrical perforation, and deformation temperature, all of which can be independently controlled. Room temperature storage of the stents was shown to be highly dependent on T(g) and crosslink density. The pressurized response of the stents is also demonstrated to depend on crosslink density. This polymer system exhibits a wide range of shape-memory and thermomechanical responses to adapt and meet specific needs of minimally invasive cardiovascular devices.
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Affiliation(s)
- Christopher M. Yakacki
- Department of Mechanical Engineering, University of Colorado at Boulder, Boulder, CO 80309-0427
| | - Robin Shandas
- Department of Mechanical Engineering, University of Colorado at Boulder, Boulder, CO 80309-0427
- Division of Cardiology, The Children’s Hospital/University of Colorado Health Science Center Denver, CO 80218
- Corresponding Author:
| | - Craig Lanning
- Division of Cardiology, The Children’s Hospital/University of Colorado Health Science Center Denver, CO 80218
| | - Bryan Rech
- Department of Mechanical Engineering, University of Colorado at Boulder, Boulder, CO 80309-0427
| | - Alex Eckstein
- Department of Mechanical Engineering, University of Colorado at Boulder, Boulder, CO 80309-0427
| | - Ken Gall
- School of Materials Science and Engineering/George Woodruff School of Mechanical Engineering Georgia Institute of Technology, Atlanta, GA 30332
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Yoshida M, Langer R, Lendlein A, Lahann J. From Advanced Biomedical Coatings to Multi‐Functionalized Biomaterials. ACTA ACUST UNITED AC 2006. [DOI: 10.1080/15583720600945394] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Grabow N, Bünger CM, Sternberg K, Mews S, Schmohl K, Schmitz KP. Mechanical Properties of a Biodegradable Balloon-expandable Stent From Poly(L-lactide) for Peripheral Vascular Applications. J Med Device 2006. [DOI: 10.1115/1.2355683] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Background: Biodegradable polymeric stents represent a competitive approach to permanent and absorbable metallic stents for vascular applications. Despite major challenges resulting from the mechanical properties of polymeric biomaterials, these stent concepts gain their attraction from their intrinsic potential for controlled biodegradation and facile drug incorporation. This study demonstrates the mechanical properties of a novel balloon-expandable slotted tube stent from PLLA. Method of Approach: Polymeric balloon-expandable slotted tube stents (nominal dimensions: 6.0×25mm) were manufactured by laser machining of solution cast tubes (I.D.=2.8mm, d=270±20μm) from biodegradable (1) PLLA and (2) PLLA/PCL/TEC. The stents were tested in vitro for their mechanical properties: deployment, recoil, shortening, collapse, and creep behavior under a static load of 100mmHg. In vitro degradation was performed in Sørensen buffer solution at 37°C. After 0∕2∕4∕8∕12∕24 weeks the remaining collapse stability and molecular weight were assessed. Results: All stents could be deployed by balloon inflation to 8bar at 1bar∕min (PLLA) and 3bar∕min (PLLA/PCL/TEC). Recoil, shortening, and collapse pressure were: 2.4%∕3.4%∕0.67bar (PLLA), and 8.8%∕2.3%∕0.23bar (PLLA/PCL/TEC). A static load of 100mmHg induced pronounced creep processes in the PLLA/PCL/TEC stent. The PLLA stent remained patent and exhibited no creep propensity. During in vitro degradation an increase in collapse pressure was observed (maxima at 12w: 1.3bar (PLLA), 0.7bar (PLLA/PCL/TEC)). At 24 weeks, molecular weight was decreased by 28% (PLLA), and 52% (PLLA/PCL/TEC). Conclusions: Stents fabricated from pure PLLA exhibited adequate mechanical properties. The slow permissible deployment rate, however, limits their potential application range and demands further development.
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Affiliation(s)
- Niels Grabow
- Institute for Biomedical Engineering, University of Rostock, Ernst-Heydemann-Str. 6, D-18057 Rostock, Germany
| | - Carsten M. Bünger
- Department of Surgery, University of Rostock, Schillingallee 35, D-18057 Rostock, Germany
| | - Katrin Sternberg
- Institute for Biomedical Engineering, University of Rostock, Ernst-Heydemann-Str. 6, D-18057 Rostock, Germany
| | - Steffen Mews
- Institute for Biomedical Engineering, University of Rostock, Ernst-Heydemann-Str. 6, D-18057 Rostock, Germany
| | - Kathleen Schmohl
- Institute for Biomedical Engineering, University of Rostock, Ernst-Heydemann-Str. 6, D-18057 Rostock, Germany
| | - Klaus-Peter Schmitz
- Institute for Biomedical Engineering, University of Rostock, Ernst-Heydemann-Str. 6, D-18057 Rostock, Germany
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Abstract
A stent is a medical device designed to serve as a temporary or permanent internal scaffold to maintain or increase the lumen of a body conduit. Metallic coronary stents were first introduced to prevent arterial dissections and to eliminate vessel recoil and intimal hyperplasia associated with percutaneous transluminal coronary angioplasty. The stent application range has expanded as more experience was gained, and encouraging results have been obtained in the treatment of vascular diseases. Stents are currently used for support of additional body conduits, including the urethra, trachea, and esophagus. The rationale for bioresorbable stents is the support of a body conduit only during its healing process. The stent mass and strength decrease with time, and the mechanical load is gradually transferred to the surrounding tissue. Bioresorbable stents also enable longer term delivery of drugs to the conduit wall from an internal reservoir and abolish the need for a second surgery to remove the device. The present review describes recent advances in bioresorbable stents, focusing on drug-eluting bioresorbable stents for various applications. Controlled release of an active agent from a stent can be used to enhance healing of the surrounding tissues, to increase the implant's biocompatibility, as well as to help cure certain diseases. Because a lot of research in this field has been done by us, examples for these functions are described based mainly on developments in our laboratories.
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Affiliation(s)
- Meital Zilberman
- Department of Biomedical Engineering, Faculty of Engineering, Tel Aviv University, Tel Aviv 69978, Israel.
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Lafont A, Li S, Garreau H, Cornhill F, Vert M. PLA stereocopolymers as sources of bioresorbable stents: Preliminary investigation in rabbit. J Biomed Mater Res B Appl Biomater 2006; 77:349-56. [PMID: 16470822 DOI: 10.1002/jbm.b.30391] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The aim of the present work was to evaluate whether the degradation of PLA-based bioresorbable stents can be modulated via the configuration of repeating units as it is the case in other applications like osteosynthesis. The first obstacle was finding a stent design that could allow implantation in the aorta of a rabbit taken as a model of a human coronary artery. In the absence of guidelines other than those tentatively proposed in patents, several simple designs were considered that allowed us to evaluate the fate of the stents made of poly(lactic acid) stereocopolymers with L/(L + D) ratio of 0.92 (PLA92) and 0.50 (PLA50) up to 6 months post in vivo implantation. Our findings show the feasibility of bioresorbable stenting using PLA stereocopolymers and that PLA50 degraded faster than PLA92. Therefore, using stereocopolymers appears as a means to vary the degradation rate and adapt it to the artery remodelling process that is very much dependent on the release of the stenting stress protection.
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Affiliation(s)
- Antoine Lafont
- INSERM E 00-16, Paris 5 Medical School, René Descartes University, Paris, France.
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45
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Wu P, Grainger DW. Drug/device combinations for local drug therapies and infection prophylaxis. Biomaterials 2005; 27:2450-67. [PMID: 16337266 DOI: 10.1016/j.biomaterials.2005.11.031] [Citation(s) in RCA: 318] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2005] [Accepted: 11/21/2005] [Indexed: 12/11/2022]
Abstract
Combination devices-those comprising drug releasing components together with functional prosthetic implants-represent a versatile, emerging clinical technology promising to provide functional improvements to implant devices in several classes. Landmark antimicrobial catheters and the drug-eluting stent have heralded the entrance, and significantly, routes to FDA approval, for these devices into clinical practice. This review describes recent strategies creating implantable combination devices. Most prominent are new combination devices representing current orthopedic and cardiovascular implants with new added capabilities from on-board or directly associated drug delivery systems are now under development. Wound coverings and implantable sensors will also benefit from this combination enhancement. Infection mitigation, a common problem with implantable devices, is a current primary focus. On-going progress in cell-based therapeutics, progenitor cell exploitation, growth factor delivery and advanced formulation strategies will provide a more general and versatile basis for advanced combination device strategies. These seek to improve tissue-device integration and functional tissue regeneration. Future combination devices might best be completely re-designed de novo to deliver multiple bioactive agents over several spatial and temporal scales to enhance prosthetic device function, instead of the current 'add-on' approach to existing implant device designs never originally intending to function in tandem with drug delivery systems.
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Affiliation(s)
- Peng Wu
- Department of Chemistry, Colorado State University, Fort Collins, CO 80523-1872, USA
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Su SH, Nguyen KT, Satasiya P, Greilich PE, Tang L, Eberhart RC. Curcumin impregnation improves the mechanical properties and reduces the inflammatory response associated with poly(L-lactic acid) fiber. JOURNAL OF BIOMATERIALS SCIENCE-POLYMER EDITION 2005; 16:353-70. [PMID: 15850289 DOI: 10.1163/1568562053654077] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
We investigated poly(L-lactic acid) (PLLA) fibers and coils, simulating stents and the influence of impregnation with curcumin, a non-steroidal anti-inflammatory drug, intended to reduce the pro-inflammatory property of these implants. Fibers obtained by melt extrusion of 137 kDa PLLA resin containing 10% curcumin (C-PLLA) exhibited a stable curcumin release rate for periods up to 36 days. Curcumin increased the fiber tensile strength at break and decreased embrittlement vs. controls in 36 day 37 degrees C saline incubation. A mouse peritoneal phagocyte model was employed to test the anti-inflammatory properties of C-PLLA fibers in vitro. Myeloperoxidase and non-specific esterase activity assays were performed for adherent cells (polymorphonuclear leukocytes (PMN) and macrophages (MPhi), respectively). PMN and MPhi adhesion to C-PLLA fibers were significantly reduced compared to control PLLA fibers (2.6 +/- 0.91) x 10(5) vs. (5.6 +/- 0.67) x 10(5) PMN/cm2 and (3.9 +/- 0.23) x 10(3) vs. (9.1 +/- 0.7) x 10(3) MPhi/cm2 (P < 0.05), respectively. In addition, superoxide release in the phagocyte pool contacting C-PLLA fibers was 97% less than that for PLLA controls. A fresh human whole blood recirculation system was employed to analyze cell adhesion under flow conditions, employing scanning electron microscopy (SEM). Reduced adhesion of cells on C-PLLA fiber coils vs. controls was observed. These in vitro studies demonstrate that bulk curcumin impregnation can reduce the inflammatory response to bioresorbable PLLA fibers, whilst improving mechanical properties, thereby suggesting curcumin loading may benefit PLLA-based implants.
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Affiliation(s)
- Shih-Horng Su
- Joint Program in Biomedical Engineering, University of Texas Southwestern Medical Center at Dallas, and The University of Texas at Arlington, TX, USA
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Zilberman M, Nelson KD, Eberhart RC. Mechanical properties andin vitro degradation of bioresorbable fibers and expandable fiber-based stents. J Biomed Mater Res B Appl Biomater 2005; 74:792-9. [PMID: 15991233 DOI: 10.1002/jbm.b.30319] [Citation(s) in RCA: 121] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Bioresorbable polymeric support devices (stents) are being developed in order to improve the biocompatibility and drug reservoir capacity of metal stents, as well as to offer a temporary alternative to permanent metallic stents. These temporary devices may be utilized for coronary, urethral, tracheal, and other applications. The present study focuses on the mechanical properties of bioresorbable fibers as well as stents developed from these fibers. Fibers made of poly(L-lactide) (PLLA), polydioxanone (PDS), and poly(glycolide-co-epsilon-caprolactone) (PGACL) were studied in vitro. These fibers combine a relatively high initial strength and modulus together with sufficient ductility and flexibility, and were therefore chosen for use in stents. The effect of degradation on the tensile mechanical properties and morphology of these fibers was examined. The expandable stents developed from these fibers demonstrated excellent initial radial compression strength. The PLLA stents exhibited excellent in vitro degradation resistance and can therefore support body conduits such as blood vessels for prolonged periods of time. PDS and PGACL stents can afford good support for 5 and 2 weeks, respectively, and can therefore be utilized for short-term applications. The degradation resistance of the stents correlates with the profile of mechanical property deterioration of the corresponding bioresorbable fibers.
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Affiliation(s)
- Meital Zilberman
- Department of Biomedical Engineering, Faculty of Engineering Tel Aviv University, Tel Aviv 69978, Israel.
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Nguyen KT, Su SH, Sheng A, Wawro D, Schwade ND, Brouse CF, Greilich PE, Tang L, Eberhart RC. In vitro hemocompatibility studies of drug-loaded poly-(L-lactic acid) fibers. Biomaterials 2004; 24:5191-201. [PMID: 14568436 DOI: 10.1016/s0142-9612(03)00451-4] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Our objective was to evaluate the hemocompatibility of biodegradable stent fibers, employing a closed-loop circulation system filled with human blood. We also investigated the effects of the anti-inflammatory and anti-proliferative drugs curcumin and paclitaxel, incorporated into stent fibers. Fresh whole blood was circulated in four parallel closed-loop systems: the empty tube circuit (control) and tubes containing either a PLLA fiber coil (PLLA), a curcumin-loaded PLLA coil (C-PLLA) or a paclitaxel-loaded PLLA coil (P-PLLA). The influence of PLLA fiber, alone or loaded with drug incorporated during melt-extrusion, on leukocyte and platelet adhesion and activation was determined by flow cytometry. The effects of blood flow and fiber properties on cell deposition were assessed by scanning electron microscopy (SEM). The flow cytometry results clearly demonstrated that PLLA triggers blood cell activation at the site of deployment, as shown by increases in CD11b, CD62P and leukocyte-platelet aggregates, compared to controls. Curcumin and paclitaxel treatments both significantly reduced leukocyte and platelet activation and adhesion to PLLA fibers, as shown by flow cytometry and SEM. Activated leukocytes and platelets revealed significantly lower CD11b and CD62P receptor binding for C-PLLA compared with PLLA alone, and slightly lower for P-PLLA. Reductions in platelet-leukocyte aggregates were observed as well. In addition, there was less leukocyte and platelet adhesion to C-PLLA, compared with PLLA fiber controls, as shown by SEM. A continuous linear thrombus, composed of platelets, leukocytes, red blood cells and fibrin was occasionally detected along the line of tangency between the coil and the tube wall. Flow separation and eddying, proximal and distal to the line of tangency of coil and tube, is thought to contribute to this deposit. Curcumin was more effective than paclitaxel in reducing leukocyte and platelet activation and adhesion to PLLA stent fibers in this setting. However there was evidence of paclitaxel degeneration during melt extrusion that may have inhibited its effectiveness. Incorporation of the anti-inflammatory and anti-proliferative drug curcumin into bioresorbable stent fibers is proposed to prevent thrombosis and in-stent restenosis.
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Affiliation(s)
- K T Nguyen
- Joint Program in Biomedical Engineering, University of Texas Southwestern Medical Center at Dallas and The University of Texas at Arlington, Dallas, TX 75390, USA
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