Name: fabrication of small caliber stent-grafts using electrospinning and balloon expandable bare metal stents
Uploaded: 2016-10-26T15:00:00.000+00:00
Duration: 6 min 55 s
Description: Watch this Scientific Journal Video about Fabrication of Small Caliber Stent-grafts Using Electrospinning and Balloon Expandable Bare Metal Stents at JoVE.com

We would like to thank the Division of Engineering, Mayo Clinic for their technical support. This study was financially supported by European Regional Development Fund - FNUSA-ICRC (No. CZ.1.05/1.100/02.0123), National Institutes of Health (T32 HL007111), American Heart Association Scientist Development Grant (AHA #06-35185N), and The Grainger Innovation Fund - Grainger Foundation.

맨드릴 수집기에 폴리 우레탄 1. 전기 방사 <ol><li> 전기 방사를위한 맨드릴 준비 <ol><li> 눈금 실린더에 생체 적합성, 식품 등급 수용성 지지체 물질의 약 8 ㎖에 녹여 (약 9mm 직경 110mm 깊이)을 오븐을 이용하여 155 ℃에서. </li><li> 맨드릴의 표면에 지지체 물질의 코팅을 얻기 위해 3 밀리미터 직경이 100 mm 인 스테인리스 강 맨드릴 담근다. 침지 전에, 용융 된 지지체 물질로 표면을 적시에 도움이 맨드릴 표면의 온도를 높이기 위해 약 15 분 동안 155 ℃에서 오븐에 배치 맨드릴. </li><li> 용융 된 지지체 물질은 맨드릴 표면에 균일 한 박막 코팅을 형성하면서 고화 침지 맨드릴은 약 140 ° C로 냉각하자. 중력 오프 적하 초과 지지체 물질이 발생되도록 냉각 과정 수직 맨드릴 걸어. 이 코팅은 쉽게 할 수 있습니다맨드릴에서 완성 된 스텐트 - 그라프의 제거. </li></ol></li><li> 전기 방사 장치의 맨드릴 수집기 설치 (도 1에 도시 된 바와 같이) <ol><li> 수평 실험실 믹서를 맞추고 흄 후드 내부의 반대 끝에 스테인리스 굴대를 개최 플라스틱 막대를 연결합니다. </li><li> 맨드릴의 단부에 플라스틱지지로드를 수용하기 위해 물에 맨드릴의 선단을 침지하여 맨드릴의 끝에서, 지지체 물질을 녹인다. 맨드릴 수집기 균일 회전을 돕기 위해 상기 맨드릴의 자유 단부의 플라스틱지지로드를 지원한다. </li><li> 스테인레스 스틸 심봉을 확보하고 전기 방사시 미끄러짐 방지하기 위해 플라스틱지지로드에 세트 나사를 사용합니다. </li><li> 스테인리스 강 맨드릴에 U 자형 접지선을 연결하여 맨드릴 수집기 정전기. 맨드릴의 측면에 접지선을 유지하도록 고무 O 링을 사용한다. </li></ol></li><li> Setti전기 방사 장치의 액체 폴리 우레탄 압출 시스템을 ng를 <ol><li> 15 %를 얻기 위해 25 % (m / v)의 폴리 우레탄 (PU) 원액의 디메틸 아세트 아미드 (DMA)를 혼합 (m / v)의 PU DMA 용액 (예를 들어, 9 ml의 25 % PU 용액에 DMA 6 ml의 추가). 주의! 적절한 개인 보호 장비와 흄 후드 내에서 작업 할 수 있습니다. </li><li> 15 % PU 솔루션 무딘 끝 스테인레스 스틸 바늘 (구금)을 5 ml의 유리 주사기를 입력합니다. </li><li> 주사기 내경에 대하여 0.01 ㎖ / 분으로 압출 주사기 펌프를 프로그래밍. </li><li> 가로 약 20cm 맨드릴 집에서 바늘 끝과 주사기 펌프에 대한 구금과 주사기를 탑재합니다. 전기 아크 발생을 피하기 위해 고무 시트를 사용하여 펌프의 주사기 도전 부에서 주사기를 절연. </li><li> 악어 클립을 사용하여 주사기의 구금으로 고전압 발생기를 연결한다. </li></ol></li><li> 0.01 ml / 분 및 로타의 시린지 펌프를 실행실험실 믹서 느린 속도 (예를 들어, 50 RPM)에서 실행하는 맨드릴을 테. </li><li> 20 kV의 전체 방사 구금과 콜렉터 맨드릴의 전압 차를 적용한다. PU 나노 섬유는 회전 맨드릴에 증착 시작하고 얇은 층은 몇 분 안에 볼 수 있습니다. 흄 후드가 꺼져 배기는 전기 방사 나노 섬유의 손실을 방지하기 위해 닫혀 있는지 확인합니다. </li></ol> 2. 스텐트 - 이식을 전기 방사 <ol><li> (1 단계에서 설명) 2 시간 동안 회전 맨드릴에 Electrospin PU 나노 파이버는 균일 한 튜브를 만들 수 있습니다. </li><li> 베어 메탈 스텐트를 설치하는 실험실 믹서에 연결된 플라스틱 막대에서 맨드릴을 제거합니다. 이전에 용매 가스가 제거되는 잔류을 보장하기 위해 맨드릴을 제거하기 흄 후드 오픈 배기를 켭니다. </li><li> 원하는 위치로 전기 방사 튜브 상에 풍선 확장 스테인레스 스틸 스텐트 (26)을 밀어 넣습니다. 이 SLI 그래서 약간 스텐트를 확장 할 필요가있다전기 방사 튜브를 손상시키지 않고에 추신. </li><li> 스텐트가 단단히 맨드릴의 튜브 재질에 설정하고 슬라이드 정도로 느슨하게되지 않았는지 확인하기 위해 스텐트 크림프. 이것은 또한 내부 및 외부 층의 박리를 방지하는 것을 도울 것이다. </li><li> 스텐트 - 그라프의 외부 층을 전기 방사를위한 실험실 믹서의 플라스틱 막대에 다시 튜브와 스텐트와 맨드릴를 넣습니다. </li><li> 1 단계에서 설명 된 바와 같이 3 시간 동안 Electrospin 나노 섬유는 스텐트 - 그라프의 외부 층을 제조한다. </li><li> 나중에 외부를 전기 방사 한 후, 원주 PU 소재를 메스를 이용하여 스텐트의 끝에서 약 1mm를 잘라. </li><li> 맨드릴에서 스텐트 - 이식을 출시 할 예정 맨드릴에서지지 물질을 용해 탈 이온수에 스텐트 - 그라프와 맨드릴을 만끽 해보세요. 완전히 지지체 물질을 용해시키기 위해 필요에 따라 신선한 물로 교체. </li><li> 지지체 물질이 용해되면 부드럽게 t에서 스텐트 - 그래프트를 제거그는 맨드릴 및 건조 할 수 있습니다. 건조 공기를 허용하기 전에 남아있는지지 물질을 용해 탈 이온수에서 제거 된 스텐트 - 이식을 몸으로 고려한다. </li></ol> 제조 스텐트 - 이식 3. 테스트 <ol><li> 3 밀리미터 3 중 풍선 스텐트 - 이식을 밀어 넣습니다. </li><li> 도구를 압착 개최 손을 사용하여 풍선에 스텐트 - 이식 크림프. </li><li> 균일 한 압착 인해 스텐트 변형 커버 재료의 박리 또는 펑크 등 고장의 징후에 대한 현미경을 사용하여 압착 스텐트 - 이식을 검사합니다. </li><li> 인플레이션 장치와 물로 3 중 풍선을 가압하여 3mm의 설계 직경의 스텐트 - 이식을 확장합니다. 다시 말하지만, 균일 한 확장과 실패의 징후에 대한 확장 된 스텐트 - 이식을 확인합니다. </li></ol>

<ol>
	<li>Elsner, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Coronary+stent+grafts+covered+by+a+polytetrafluoroethylene+membrane.">Coronary stent grafts covered by a polytetrafluoroethylene membrane.</a> Am. J. Cardiol. 84 (3), 335-338 (1999).</li><li>St&#246;rger, H., Haase, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Polytetrafluoroethylene-Covered+Stents:+Indications,+Advantages,+and+Limitations.">Polytetrafluoroethylene-Covered Stents: Indications, Advantages, and Limitations.</a> J. Interv. Cardiol. 12 (6), 451-456 (1999).</li><li>Moreno, P. R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Macrophage+infiltration+predicts+restenosis+after+coronary+intervention+in+patients+with+unstable+angina.">Macrophage infiltration predicts restenosis after coronary intervention in patients with unstable angina.</a> Circulation. 94 (12), 3098-3102 (1996).</li><li>Briguori, C., Sarais, C., Colombo, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+polytetrafluoroethylene-covered+stent:+a+device+with+multiple+potential+advantages.">The polytetrafluoroethylene-covered stent: a device with multiple potential advantages.</a> Int. J. Cardiovasc. Interv. 4 (3), 145-149 (2001).</li><li>Qureshi, M. A., Martin, Z., Greenberg, R. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Endovascular+management+of+patients+with+Takayasu+arteritis:+stents+versus+stent+grafts.">Endovascular management of patients with Takayasu arteritis: stents versus stent grafts.</a> Semin. Vasc. Surg. 24 (1), 44-52 (2011).</li><li>Ahmadi, R., Schillinger, M., Maca, T., Minar, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Femoropopliteal+arteries:+immediate+and+long-term+results+with+a+Dacron-covered+stent-graft.">Femoropopliteal arteries: immediate and long-term results with a Dacron-covered stent-graft.</a> Radiology. 223 (2), 345-350 (2002).</li><li>Geremia, G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Experimental+arteriovenous+fistulas:+treatment+with+silicone-covered+metallic+stents.">Experimental arteriovenous fistulas: treatment with silicone-covered metallic stents.</a> AJNR. Am. J. Neuroradiol. 18 (2), 271-277 (1997).</li><li>Saatci, I., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Treatment+of+internal+carotid+artery+aneurysms+with+a+covered+stent:+experience+in+24+patients+with+mid-term+follow-up+results.">Treatment of internal carotid artery aneurysms with a covered stent: experience in 24 patients with mid-term follow-up results.</a> AJNR. Am. J. Neuroradiol. 25 (10), 1742-1749 (2004).</li><li>Stefanadis, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stents+Wrapped+in+Autologous+Vein:+An+Experimental+Study1.">Stents Wrapped in Autologous Vein: An Experimental Study1.</a> J. Am. Coll. Cardiol. 28 (4), 1039-1046 (1996).</li><li>Palmaz, J. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Review+of+polymeric+graft+materials+for+endovascular+applications.">Review of polymeric graft materials for endovascular applications.</a> J. Vasc. Interv. Radiol. 9, 7-13 (1998).</li><li>Bruckheimer, E., Dagan, T., Amir, G., Birk, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Covered+Cheatham-Platinum+stents+for+serial+dilation+of+severe+native+aortic+coarctation.">Covered Cheatham-Platinum stents for serial dilation of severe native aortic coarctation.</a> Catheter Cardiovasc. Interv. 74 (1), 117-123 (2009).</li><li>Tzifa, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Covered+Cheatham-platinum+stents+for+aortic+coarctation:+early+and+intermediate-term+results.">Covered Cheatham-platinum stents for aortic coarctation: early and intermediate-term results.</a> J. Am. Coll. Cardiol. 47 (7), 1457-1463 (2006).</li><li>Kuraishi, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Development+of+nanofiber-covered+stents+using+electrospinning:+in+vitro+and+acute+phase+in+vivo+experiments.">Development of nanofiber-covered stents using electrospinning: in vitro and acute phase in vivo experiments.</a> J. Biomed. Mater. Res. Part B Appl. Biomater. 88 (1), 230-239 (2009).</li><li>Pant, S., Bressloff, N. W., Limbert, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Geometry+parameterization+and+multidisciplinary+constrained+optimization+of+coronary+stents.">Geometry parameterization and multidisciplinary constrained optimization of coronary stents.</a> Biomech. Model Mechanobiol. 11 (1-2), 61-82 (2012).</li><li>Muller-Hulsbeck, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Experience+on+endothelial+cell+adhesion+on+vascular+stents+and+stent-grafts:+first+in+vitro+results.">Experience on endothelial cell adhesion on vascular stents and stent-grafts: first in vitro results.</a> Invest. Radiol. 37 (6), 314-320 (2002).</li><li>Sarkar, S., Salacinski, H. J., Hamilton, G., Seifalian, A. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+mechanical+properties+of+infrainguinal+vascular+bypass+grafts:+their+role+in+influencing+patency.">The mechanical properties of infrainguinal vascular bypass grafts: their role in influencing patency.</a> Eur. J. Vasc. Endovasc. Surg. 31 (6), 627-636 (2006).</li><li>Shirota, T., Yasui, H., Shimokawa, H., Matsuda, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fabrication+of+endothelial+progenitor+cell+(EPC)-seeded+intravascular+stent+devices+and+in+vitro+endothelialization+on+hybrid+vascular+tissue.">Fabrication of endothelial progenitor cell (EPC)-seeded intravascular stent devices and in vitro endothelialization on hybrid vascular tissue.</a> Biomaterials. 24 (13), 2295-2302 (2003).</li><li>Grasl, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electrospun+polyurethane+vascular+grafts:+in+vitro+mechanical+behavior+and+endothelial+adhesion+molecule+expression.">Electrospun polyurethane vascular grafts: in vitro mechanical behavior and endothelial adhesion molecule expression.</a> J. Biomed. Mater. Res. A. 93 (2), 716-723 (2010).</li><li>Kidoaki, S., Kwon, I. K., Matsuda, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Structural+features+and+mechanical+properties+of+in+situ-bonded+meshes+of+segmented+polyurethane+electrospun+from+mixed+solvents.">Structural features and mechanical properties of in situ-bonded meshes of segmented polyurethane electrospun from mixed solvents.</a> J. Biomed. Mater. Res. Part B Appl. Biomater. 76 (1), 219-229 (2006).</li><li>Stegemann, J. P., Kaszuba, S. N., Rowe, S. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Review:+advances+in+vascular+tissue+engineering+using+protein-based+biomaterials.">Review: advances in vascular tissue engineering using protein-based biomaterials.</a> Tissue Eng. 13 (11), 2601-2613 (2007).</li><li>Sankaran, K. K., Subramanian, A., Krishnan, U. M., Sethuraman, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nanoarchitecture+of+scaffolds+and+endothelial+cells+in+engineering+small+diameter+vascular+grafts.">Nanoarchitecture of scaffolds and endothelial cells in engineering small diameter vascular grafts.</a> Biotechnol. J. 10 (1), 96-108 (2015).</li><li>Gibson, P., Schreuder-Gibson, H., Rivin, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transport+properties+of+porous+membranes+based+on+electrospun+nanofibers.">Transport properties of porous membranes based on electrospun nanofibers.</a> Colloid Surf., A. 187, 469-481 (2001).</li><li>Zdrahala, R. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Small+caliber+vascular+grafts.+Part+II:+Polyurethanes+revisited.">Small caliber vascular grafts. Part II: Polyurethanes revisited.</a> J. Biomater. Appl. 11 (1), 37-61 (1996).</li><li>Uthamaraj, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Design+and+validation+of+a+novel+ferromagnetic+bare+metal+stent+capable+of+capturing+and+retaining+endothelial+cells.">Design and validation of a novel ferromagnetic bare metal stent capable of capturing and retaining endothelial cells.</a> Ann. Biomed. Eng. 42 (12), 2416-2424 (2014).</li><li>Tefft, B. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cell+Labeling+and+Targeting+with+Superparamagnetic+Iron+Oxide+Nanoparticles.">Cell Labeling and Targeting with Superparamagnetic Iron Oxide Nanoparticles.</a> J. Vis. Exp. (105), e53099 (2015).</li><li>Uthamaraj, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ferromagnetic+Bare+Metal+Stent+for+Endothelial+Cell+Capture+and+Retention.">Ferromagnetic Bare Metal Stent for Endothelial Cell Capture and Retention.</a> J. Vis. Exp. (103), e53100 (2015).</li><li>de Giovanni, J. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Covered+stents+in+the+treatment+of+aortic+coarctation.">Covered stents in the treatment of aortic coarctation.</a> J. Interv. Cardiol. 14 (2), 187-190 (2001).</li><li>Hans, F. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Treatment+of+wide-necked+aneurysms+with+balloon-expandable+polyurethane-covered+stentgrafts:+experience+in+an+animal+model.">Treatment of wide-necked aneurysms with balloon-expandable polyurethane-covered stentgrafts: experience in an animal model.</a> Acta. Neurochir. (Wien). 147 (8), 871-876 (2005).</li><li>Hasan, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Electrospun+scaffolds+for+tissue+engineering+of+vascular+grafts.">Electrospun scaffolds for tissue engineering of vascular grafts.</a> Acta. Biomater. 10 (1), 11-25 (2014).</li></ol>

저자는 더 경쟁 재정적 이해 관계가 없음을 선언합니다.

We have developed a fabrication technique for a small caliber stent-graft which can be deployed using a standard percutaneous coronary intervention (PCI) procedure. Stent-grafts currently available are limited in their ability to maintain a low profile and flexibility for deployment. Bare metal stents developed by our group in our previous studies have proven to assist in rapid healing of the stented artery24,26. Various polymers have been electrospun by other groups and polyurethane has been proven biostable ...

관상 동맥 중재 절차에 의한 플라크와 용기 벽의 파괴에 중요한 혈관 벽의 부상을 입을 수 있습니다. 이것은 관상 동맥 내강 1-4의 재 협착, 정맥 이식 말초 색전증 및 단절을 초래한다. 이러한 합병증을 방지하기 위해 유망 전략은 잠재적으로, 재 협착을 억제하는 혈관 내강의 불연속에서 위험을 완화하고, 주변 색전증을 방지 할 혈관 성형술 사이트에있는 혈관 표면을 커버하는 것입니다. 이전 연구는 스텐트 - 이식 5 긍정적 인 결과와-이식을 스텐트 베어 메탈 스텐트를 비교했다. 연구자들은 스텐트를 충당하기 위해 멤브레인을 제조하는 여러 가지 재료를 사용하고 있습니다. 이것은 폴리에틸렌 tetraphthalate (PET), 폴리 테트라 플루오로 에틸렌 (PTFE), 폴리 우레탄 (PU), 실리콘 또는 피복 스텐트 6-9를 제조하는자가 혈관 조직 등 합성 재료를 포함한다. 스텐트를 피복하는 데 이상적인 그래프트 재료는 비 biodegr, thromboresistant되어야adable, 과도한 증식과 염증 (10)없이 기본 조직과 통합해야합니다. 스텐트를 피복하는 데 사용되는 그래프트 재료는 스텐트 - 그래프트의 치유를 촉진한다. 스텐트 - 이식 널리 대동맥 축착, 경동맥의 의사 동맥류, 동정맥루의 치료에 사용되는, 이식 정맥 퇴화, 거대한 대뇌 동맥류에 큰. 그러나 작은 구경 스텐트 - 이식의 발전은 스텐트 - 이식 11 ~ 14의 배치에 에이즈 낮은 프로파일과 유연성을 유지하는 능력에 의해 제한된다. PU는 낮은 프로파일 및 우수한 유연성 (15, 16)을 달성하기위한 바람직한 특성 인 우수한 기계적 강도를 갖는 탄성 중합체이다. 좋은 배달 가능성을 가진뿐만 아니라, 스텐트 - 이식은 빠른 치유와 내피 세포 형성을 촉진한다. PU는 스텐트 - 이식 더 나은 생체 적합성을 입증하고 내피 세포 형성 (17)을 강화했다 덮여있다. 연구진은이이전 PU는 내피 세포 (17)를 파종하여 스텐트 - 이식 덮여 endothelialize했습니다. 나노 섬유 매트릭스를 생성하는 전기 방사 PU의 혈관의 생성은 18, 19을 접목하는 중요한 기술이 될 것으로 밝혀졌다. 원시 세포 외 기질의 구조를 모방하는 나노 섬유의 존재는 또한 내피 세포 증식 (20, 21)를 촉진하는 것으로 알려져있다. 전기 방사는 재료 (22)의 두께를 제어 할 수 있습니다. PU 이루어지는 소 구경 혈관 이식편은 표면 코팅, 항 응집제 및 세포 증식 억제제와 같은 변형을 사용하여 치료를 촉진하기 위해 연구되어왔다. 이러한 모든 수정은 호스트 수용을 중재 및 이식 치료 (23)을 촉진하기 위해 설계되었습니다. 우리 그룹은 동물 모델 24-26 배포 할 수 있습니다 풍선 확장 베어 메탈 스텐트를 개발했다. 전기 방사 우레탄 메쉬와 공의 조합지운 확장 스텐트는 작은 구경의 풍선 확장형 스텐트 - 이식을 생성 할 수있게되었습니다. 현재 사용 가능한 스텐트 이식의 대부분은 중재 절차 중 대퇴부 동맥을 통해 도입되어 있지만, 몇 상업적 피복 스텐트는 비 - 팽창기구 (27)에 필요한 것보다 더 큰 일 프랑스어 크기를 도입 할 수있다. 본 연구에서 우리는 경피적 중재 절차 표준 8-9 프랑스어 안내 카테터를 사용하여 관상 동맥에 전달 될 수있는 전기 방사 PU의 두 층 사이의 벌룬 확장형 스텐트 캡슐화 작은 구경 혈관 스텐트 - 그래프트를 개발했다.

<table><tbody><tr><td>Glass syringe</td><td>Air Tite</td><td>7.140-33</td><td>Syringe for spinneret</td></tr><tr><td>Graduated cylinder 5 ml</td><td>Fisher Scientific</td><td>08-552-4G</td><td>5 ml pyrex graduated cylinder about 9 mm diameter and 11 cm long</td></tr><tr><td>High voltage generator</td><td>Bertan Accociates, Inc.</td><td>205A-30P</td><td>Used to apply voltage difference across spinneret and collector</td></tr><tr><td>Laboratory mixer with rpm control</td><td>Scilogex</td><td>SCI-84010201</td><td>Available from various laboratory equipment suppliers</td></tr><tr><td>Polyurethane</td><td>DSM</td><td>BioSpan SPU</td><td>Biospan Segmented Polyurethane</td></tr><tr><td>Rubber sheet</td><td>McMaster Carr</td><td>1370N11</td><td>Used to insulate syringe during electrospinning</td></tr><tr><td>Stainless steel mandrel</td><td>N/A</td><td>N/A</td><td>Manufactured&amp;nbsp;</td></tr><tr><td>Stainless steel needle</td><td>Hamilton</td><td>91018</td><td>Used as spinneret in electrospinning</td></tr><tr><td>Support material</td><td>EnvisionTec</td><td>B04-HT-DEMOMAT</td><td>Biocompatible water soluble material</td></tr><tr><td>Syringe Pump</td><td>Harvard Apparatus</td><td>55-3333</td><td></td></tr></tbody></table>

fabrication of small caliber stent-grafts using electrospinning and balloon expandable bare metal stents

Stent-grafts are widely used for the treatment of various conditions such as aortic lesions, aneurysms, emboli due to coronary intervention procedures and perforations in vasculature. Such stent-grafts are manufactured by covering a stent with a polymer membrane. An ideal stent-graft should have a biocompatible stent covered by a porous, thromboresistant, and biocompatible polymer membrane which mimics the extracellular matrix thereby promoting injury site healing. The goal of this protocol is to manufacture a small caliber stent-graft by encapsulating a balloon expandable stent within two layers of electrospun polyurethane nanofibers. Electrospinning of polyurethane has been shown to assist in healing by mimicking native extracellular matrix, thereby promoting endothelialization. Electrospinning polyurethane nanofibers on a slowly rotating mandrel enabled us to precisely control the thickness of the nanofibrous membrane, which is essential to achieve a small caliber balloon expandable stent-graft. Mechanical validation by crimping and expansion of the stent-graft has shown that the nanofibrous polyurethane membrane is sufficiently flexible to crimp and expand while staying patent without showing any signs of tearing or delamination. Furthermore, stent-grafts fabricated using the methods described here are capable of being implanted using a coronary intervention procedure using standard size guide catheters.

<html> 우리 electrospinner 설정 (그림 1)는 고품질의 폴리 우레탄 나노 섬유 (그림 2) 가져왔다. 스텐트 - 그래프트는 (도 3), 맨드릴 상에, 폴리 우레탄의 내층을 전기 방사이 층 위에 노출 된 금속 스텐트 슬립, 폴리 우레탄의 제 2 외측 층을 전기 방사에 의해 제조된다. 우레탄 나노 파이버는 100 ㎛, 내층 및 스텐트 이식 150 ㎛, 외층 결과 50㎛의 / 시간의 속도로 전기 ?...

Watch this Scientific Journal Video about Fabrication of Small Caliber Stent-grafts Using Electrospinning and Balloon Expandable Bare Metal Stents at JoVE.com

Fabrication of Small Caliber Stent-grafts Using Electrospinning and Balloon Expandable Bare Metal Stents

In the protocol, we present a method to manufacture a small caliber stent-graft by sandwiching a balloon expandable stent between two electrospun nanofibrous polyurethane layers.

전기 방사 및 풍선 확장 베어 메탈 스텐트를 사용하여 작은 구경 스텐트 - 이식의 제작

Stent-grafts are widely used for the treatment of various conditions such as aortic lesions, aneurysms, emboli due to coronary intervention procedures and ...

fabrication-small-caliber-stent-grafts-using-electrospinning-balloon

Research

JoVE Journal

Medicine

8.8K 조회수.  Mayo Clinic. In the protocol, we present a method to manufacture a small caliber stent-graft by sandwiching a balloon expandable stent between two electrospun nanofibrous polyurethane layers.

비디오: Fabrication of Small Caliber Stent-grafts Using Electrospinning and Balloon Expandable Bare Metal Stents

Postproduction Processing of Electrospun Fibres for Tissue Engineering

Electrospinning is a commonly used and versatile method to produce scaffolds (often biodegradable) for 3D tissue engineering.1, 2, 3 Many tissues in vivo undergo biaxial distension to varying extents such as skin, bladder, pelvic floor and even the hard palate as children grow. In producing scaffolds for these purposes there is a need to develop scaffolds of appropriate biomechanical properties (whether achieved without or with cells) and which are sterile for clinical use. The focus of this paper is not how to establish basic electrospinning parameters (as there is extensive literature on electrospinning) but on how to modify spun scaffolds post production to make them fit for tissue engineering purposes - here thickness, mechanical properties and sterilisation (required for clinical use) are considered and we also describe how cells can be cultured on scaffolds and subjected to biaxial strain to condition them for specific applications.
Electrospinning tends to produce thin sheets; as the electrospinning collector becomes coated with insulating fibres it becomes a poor conductor such that fibres no longer deposit on it. Hence we describe approaches to produce thicker structures by heat or vapour annealing increasing the strength of scaffolds but not necessarily the elasticity. Sequential spinning of scaffolds of different polymers to achieve complex scaffolds is also described. Sterilisation methodologies can adversely affect strength and elasticity of scaffolds. We compare three methods for their effects on the biomechanical properties on electrospun scaffolds of poly lactic-co-glycolic acid (PLGA).
Imaging of cells on scaffolds and assessment of production of extracellular matrix (ECM) proteins by cells on scaffolds is described. Culturing cells on scaffolds in vitro can improve scaffold strength and elasticity but the tissue engineering literature shows that cells often fail to produce appropriate ECM when cultured under static conditions. There are few commercial systems available that allow one to culture cells on scaffolds under dynamic conditioning regimes - one example is the Bose Electroforce 3100 which can be used to exert a conditioning programme on cells in scaffolds held using mechanical grips within a media filled chamber.4 An approach to a budget cell culture bioreactor for controlled distortion in 2 dimensions is described. We show that cells can be induced to produce elastin under these conditions. Finally assessment of the biomechanical properties of processed scaffolds cultured with or without cells is described.

Electrospun scaffolds can be processed post production for tissue engineering applications. Here we describe methods for spinning complex scaffolds (by consecutive spinning), for making thicker scaffolds (by multi-layering using heat or vapour annealing), for achieving sterility (aseptic production or sterilisation post production) and for achieving appropriate biomechanical properties.

조직 공학을위한 Electrospun의 Fibres의 Postproduction 처리

Electrospinning is a commonly used and versatile method to produce  scaffolds (often biodegradable) for 3D tissue engineering.1, 2, 3 Many tissues in vivo ...

연구

생체공학

A Murine Model of Stent Implantation in the Carotid Artery for the Study of Restenosis

Despite the considerable progress made in the stent development in the last decades, cardiovascular diseases remain the main cause of death in western countries. Beside the benefits offered by the development of different drug-eluting stents, the coronary revascularization bears also the life-threatening risks of in-stent thrombosis and restenosis. Research on new therapeutic strategies is impaired by the lack of appropriate methods to study stent implantation and restenosis processes. Here, we describe a rapid and accessible procedure of stent implantation in mouse carotid artery, which offers the possibility to study in a convenient way the molecular mechanisms of vessel remodeling and the effects of different drug coatings.

A model of stent implantation in mouse carotid artery is described. Compared to other similar methods, this procedure is very rapid, simple and accessible, offering the possibility to study in a convenient way the vascular wall reaction to different drug-eluting stents and the molecular mechanisms of restenosis.

재 협착의 연구에 대한 경동맥 스텐트 시술의 쥐과 모형

Despite  the considerable progress made in the stent development in the last decades,  cardiovascular diseases remain the main cause of death in western ...

의학

Combination of Microstereolithography and Electrospinning to Produce Membranes Equipped with Niches for Corneal Regeneration

Corneal problems affect millions of people worldwide reducing their quality of life significantly. Corneal disease can be caused by illnesses such as Aniridia or Steven Johnson Syndrome as well as by external factors such as chemical burns or radiation. Current treatments are (i) the use of corneal grafts and (ii) the use of stem cell expanded in the laboratory and delivered on carriers (e.g., amniotic membrane); these treatments are relatively successful but unfortunately they can fail after 3-5 years. There is a need to design and manufacture new corneal biomaterial devices able to mimic in detail the physiological environment where stem cells reside in the cornea. Limbal stem cells are located in the limbus (circular area between cornea and sclera) in specific niches known as the Palisades of Vogt. In this work we have developed a new platform technology which combines two cutting-edge manufacturing techniques (microstereolithography and electrospinning) for the fabrication of corneal membranes that mimic to a certain extent the limbus. Our membranes contain artificial micropockets which aim to provide cells with protection as the Palisades of Vogt do in the eye.

We report a technique for the fabrication of micropockets within electrospun membranes in which to study cell behavior. Specifically, we describe a combination of microstereolithography and electrospinning for the production of PLGA (Poly(lactide-co-glycolide)) corneal biomaterial devices equipped with microfeatures.

마이크로 광 및 전기 방사의 조합은 각막 재생을위한 틈새를 장착 멤브레인을 생산하는

Corneal problems affect millions of people worldwide reducing their quality of life significantly. Corneal disease can be caused by illnesses such as ...

Ferromagnetic Bare Metal Stent for Endothelial Cell Capture and Retention

Rapid endothelialization of cardiovascular stents is needed to reduce stent thrombosis and to avoid anti-platelet therapy which can reduce bleeding risk. The feasibility of using magnetic forces to capture and retain endothelial outgrowth cells (EOC) labeled with super paramagnetic iron oxide nanoparticles (SPION) has been shown previously. But this technique requires the development of a mechanically functional stent from a magnetic and biocompatible material followed by in-vitro and in-vivo testing to prove rapid endothelialization. We developed a weakly ferromagnetic stent from 2205 duplex stainless steel using computer aided design (CAD) and its design was further refined using finite element analysis (FEA). The final design of the stent exhibited a principal strain below the fracture limit of the material during mechanical crimping and expansion. One hundred stents were manufactured and a subset of them was used for mechanical testing, retained magnetic field measurements, in-vitro cell capture studies, and in-vivo implantation studies. Ten stents were tested for deployment to verify if they sustained crimping and expansion cycle without failure. Another 10 stents were magnetized using a strong neodymium magnet and their retained magnetic field was measured. The stents showed that the retained magnetism was sufficient to capture SPION-labeled EOC in our in-vitro studies. SPION-labeled EOC capture and retention was verified in large animal models by implanting 1 magnetized stent and 1 non-magnetized control stent in each of 4 pigs. The stented arteries were explanted after 7 days and analyzed histologically. The weakly magnetic stents developed in this study were capable of attracting and retaining SPION-labeled endothelial cells which can promote rapid healing.

Our goals were to design, manufacture and test ferromagnetic stents for endothelial cell capture. Ten stents were tested for fracture and 10 more stents were tested for retained magnetism. Finally, 10 stents were tested in-vitro and 8 more stents were implanted in 4 pigs to show cell capture and retention.

내피 세포 캡처 및 유지에 대한 강자성 베어 메탈 스텐트

Rapid endothelialization of cardiovascular stents is needed to reduce stent thrombosis and to avoid anti-platelet therapy which can reduce bleeding risk. ...

4D Printed Bifurcated Stents with Kirigami-Inspired Structures

Branched vessels, typically in the form of the letter &#34;Y,&#34;&#160;can be narrowed or blocked, resulting in serious health problems. Bifurcated stents, which are hollow in the interior and exteriorly shaped to the branched vessels, surgically inserted inside the branched vessels, act as a supporting structure so that bodily fluids can freely travel through the interior of the stents without being obstructed by the narrowed or blocked vessels. For a bifurcated stent to be deployed at the target site, it needs to be injected inside the vessel and travel within the vessel to reach the target site. The diameter of the vessel is much smaller than the bounding sphere of the bifurcated stent; thus, a technique is required so that the bifurcated stent remains small enough to travel through the vessel and expands at the targeted branched vessel. These two conflicting conditions, that is, small enough to pass through and large enough to structurally support narrowed passages, are extremely difficult to satisfy simultaneously. We use two techniques to fulfill the above requirements. First, on the material side, a shape memory polymer (SMP) is used to self-initiate shape changes from small to large, that is, being small when inserted and becoming large at the target site. Second, on the design side, a kirigami pattern is used to fold the branching tubes into a single tube with a smaller diameter. The presented techniques can be used to engineer structures that can be compacted during transportation and return to their functionally adept shape when activated. Although our work is targeted on medical stents, biocompatibility issues need to be solved before actual clinical use.

Using a 3D printer, a shape memory polymer filament is extruded to form a branched tubular structure. The structure is patterned and shaped such that it can contract into a compact form once folded and then return to its formed shape when heated.

키리가미에서 영감을 받은 구조의 4D 인쇄 된 분기식 스텐트

Branched vessels, typically in the form of the letter &#34;Y,&#34;&#160;can be narrowed or blocked, resulting in serious health problems. Bifurcated ...

공학

<meta charset="utf8"></head><body>희생 구리 설비를 사용한 NiTi 와이어의 비용 효율적인 형상 설정

Rapid Formation and Testing of Self-expanding NiTi Frames with a Small Form Factor Suitable for Minimally Invasive Implants

NiTiNOL (commonly referred to as nitinol or NiTi) wires feature exceptional shape memory and super-elastic characteristics, while shape-setting is often a costly process. Among the steps in&#160;this process, heat treatment requires exposure to high temperatures for shape-setting. Traditionally, metal fixtures are used for this purpose.&#160;However, their manufacturing costs can be significant, which is unideal&#160;for iterating prototypes. This work demonstrates a recently introduced approach using sacrificial fixtures made of copper tubes, which eliminates the need for expensive fixtures. These copper tubes allow for the formation of complex geometries, and they offer a scaffold for various phases of the fabrication process. Moreover, ammonium persulfate is used&#160;for selective copper etching, which simplifies the production of NiTi frames. This work&#39;s findings confirm the effectiveness of this technique and&#160;demonstrate&#160;the successful shape-setting of NiTi wires for self-expanding frames. This methodology paves the way for future research, allowing for rapid prototyping of NiTi wireframes for various applications, especially those in medical devices.

<meta charset="utf8"></head><body>저자 스포트라이트: Transcatheter 이식형 장치를 위한 자가 확장 니티놀 프레임의 신속한 프로토타이핑 및 테스트

This work illustrates a low-cost fabrication technique for shape-setting nitinol wires/frames with a small form factor using sacrificial fixtures. The technique is demonstrated for the fabrication of self-expanding frames designed for minimally invasive implants with complex shapes.

최소 침습 임플란트에 적합한 소형 폼 팩터를 갖춘 자체 팽창 NiTi 프레임의 신속한 형성 및 테스트

NiTiNOL (commonly referred to as nitinol or NiTi) wires feature exceptional shape memory and super-elastic characteristics, while shape-setting is often a ...

Biodegradable Magnesium Stent Treatment of Saccular Aneurysms in a Rat Model - Introduction of the Surgical Technique

The steady progess in the armamentarium of techniques available for endovascular treatment of intracranial aneurysms requires affordable and reproducable experimental animal models to test novel embolization materials such as stents and flow diverters. The aim of the present project was to design a safe, fast, and standardized surgical technique for stent assisted embolization of saccular aneurysms in a rat animal model.
Saccular aneurysms were created from an arterial graft from the descending aorta.The aneurysms were microsurgically transplanted through end-to-side anastomosis to the infrarenal abdominal aorta of a syngenic male Wistar rat weighing &#62;500 g. Following aneurysm anastomosis, aneurysm embolization was performed using balloon expandable magnesium stents (2.5 mm x 6 mm). The stent system was retrograde introduced from the lower abdominal aorta using a modified Seldinger technique.
Following a pilot series of 6 animals, a total of 67 rats were operated according to established standard operating procedures. Mean surgery time, mean anastomosis time, and mean suturing time of the artery puncture site were 167 &#177; 22 min, 26 &#177; 6 min and 11 &#177; 5 min, respectively. The mortality rate was 6% (n=4). The morbidity rate was 7.5% (n=5), and in-stent thrombosis was found in 4 cases (n=2 early, n=2 late in stent thrombosis).
The results demonstrate the feasibility of standardized stent occlusion of saccular sidewall aneurysms in rats - with low rates of morbidity and mortality. This stent embolization procedure combines the opportunity to study novel concepts of stent or flow diverter based devices as well as the molecular aspects of healing.

Reproducable experimental animal models are needed for the testing of novel embolization materials, which have been designed to treat endovascular occlusion of intracranial aneurysms (IA). The present study aims to develop a safe and standardized surgical technique for stent assisted embolization of saccular aneurysms in a rat animal model.

쥐 모델-수술 방법의 소개에에서 Saccular 동맥 류의 생 분해성 마그네슘 스 텐트 치료

The steady progess in the armamentarium of techniques available for endovascular treatment of intracranial aneurysms requires affordable and reproducable ...

신경과학

Combining 3D-Printing and Electrospinning to Manufacture Biomimetic Heart Valve Leaflets

Electrospinning has become a widely used technique in cardiovascular tissue engineering as it offers the possibility to create (micro-)fibrous scaffolds with adjustable properties. The aim of this study was to create multilayered scaffolds mimicking the architectural fiber characteristics of human heart valve leaflets using conductive 3D-printed collectors.
Models of aortic valve cusps were created using commercial computer-aided design (CAD) software. Conductive polylactic acid was used to fabricate 3D-printed leaflet templates. These cusp negatives were integrated into a specifically designed, rotating electrospinning mandrel. Three layers of polyurethane were spun onto the collector, mimicking the fiber orientation of human heart valves. Surface and fiber structure was assessed with a scanning electron microscope (SEM). The application of fluorescent dye additionally permitted the microscopic visualization of the multilayered fiber structure. Tensile testing was performed to assess the biomechanical properties of the scaffolds.
3D-printing of essential parts for the electrospinning rig was possible in a short time for a low budget. The aortic valve cusps created following this protocol were three-layered, with a fiber diameter of 4.1 &#177; 1.6 &#181;m. SEM imaging revealed an even distribution of fibers. Fluorescence microscopy revealed individual layers with differently aligned fibers, with each layer precisely reaching the desired fiber configuration. The produced scaffolds showed high tensile strength, especially along the direction of alignment. The printing files for the different collectors are available as Supplemental File 1, Supplemental File 2, Supplemental File 3, Supplemental File 4, and Supplemental File 5.
With a highly specialized setup and workflow protocol, it is possible to mimic tissues with complex fiber structures over multiple layers. Spinning directly on 3D-printed collectors creates considerable flexibility in manufacturing 3D shapes at low production costs.

The presented method offers an innovative way for engineering biomimetic fiber structures in three-dimensional (3D) scaffolds (e.g., heart valve leaflets). 3D-printed, conductive geometries were used to determine shape and dimensions. Fiber orientation and characteristics were individually adjustable for each layer. Multiple samples could be manufactured in one setup.

3D 프린팅과 전기방사를 결합하여 생체모방 심장 판막 전단지 제조

Electrospinning has become a widely used technique in cardiovascular tissue engineering as it offers the possibility to create (micro-)fibrous scaffolds ...

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