MP53-19 FEASIBILITY OF DRUG-ELUTING BIODEGRADABLE STENT FOR URETERAL STRICTURE TREATMENT IN AN ANIMAL MODEL

In this study, we investigated the effect of mTOR inhibitor (mTORi) drug-eluting biodegradable stent (DE stent), a putative restenosis-inhibiting device for coronary artery, on thermal-injury-related ureteral stricture in rabbits. In vitro evaluation confirmed the dose-dependent effect of mTORi, i.e., rapamycin, on fibrotic markers in ureteral component cell lines. Upper ureteral fibrosis was induced by ureteral thermal injury in open surgery, which was followed by insertion of biodegradable stents, with or without rapamycin drug-eluting. Immunohistochemistry and Western blotting were performed 4 weeks after the operation to determine gross anatomy changes, collagen deposition, expression of epithelial–mesenchymal transition markers, including Smad, α-SMA, and SNAI 1. Ureteral thermal injury resulted in severe ipsilateral hydronephrosis. The levels of type III collagen, Smad, α-SMA, and SNAI 1 were increased 28 days after ureteral thermal injury. Treatment with mTORi-eluting biodegradable stents significantly attenuated thermal injury-induced urinary tract obstruction and reduced the level of fibrosis proteins, i.e., type III collagen. TGF-β and EMT signaling pathway markers, Smad and SNAI 1, were significantly modified in DE stent-treated thermal-injury-related ureteral stricture rabbits. These results suggested that intra-ureteral administration of rapamycin by DE stent provides modification of fibrosis signaling pathway, and inhibiting mTOR may result in fibrotic process change.

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Thermo-Induced Shape-Memory PEG-PCL Copolymer as a Dual-Drug-Eluting Biodegradable Stent

ACS Applied Materials & Interfaces ◽

10.1021/am4032295 ◽

2013 ◽

Vol 5 (21) ◽

pp. 10985-10994 ◽

Cited By ~ 69

Author(s):

Chien-Shen Yang ◽

Hsi-Chin Wu ◽

Jui-Sheng Sun ◽

Hao-Ming Hsiao ◽

Tzu-Wei Wang

Keyword(s):

Shape Memory ◽

Biodegradable Stent ◽

Drug Eluting ◽

Dual Drug

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Local paclitaxel delivery after coronary stenting in an experimental animal model

Thrombosis and Haemostasis ◽

10.1160/th07-01-0074 ◽

2007 ◽

Vol 98 (09) ◽

pp. 674-680 ◽

Cited By ~ 20

Author(s):

Christoph Dommke ◽

Tim Süselbeck ◽

Ines Streitner ◽

Dariush Haghi ◽

Jürgen Metz ◽

...

Keyword(s):

Animal Model ◽

Experimental Animal ◽

Stent Implantation ◽

Balloon Dilatation ◽

Sham Group ◽

Experimental Animal Model ◽

Metal Stents ◽

Control Group ◽

Bare Metal ◽

Drug Eluting

SummaryThe goal of this study was to test the safety and efficacy of local paclitaxel delivery via a newly designed application catheter in an experimental animal study. Drug-eluting stents reduce restenosis in comparison to bare-metal stents. The drug-eluting polymer, however, may exert potential thrombogenic and inflammatory effects. A catheter-based local paclitaxel delivery offers further advantages, particularly a homogenous drug transfer into the vessel wall and a pharmacotherapy of the stent edges. In 30 pigs, both bare-metal stent (3.0 × 13mm) implantation and balloon angioplasty were performed. Ten pigs received subsequent local delivery of paclitaxel-solution via a newly designed catheter (Genie™, ACROSTAK corp., Switzerland), 10 animals served as a sham group and received vehicle (0.9% NaCl solution) and 10 animals were used as a control group. All animals were treated with aspirin and clopidogrel to prevent stent thrombosis. After final angiography the vessels were excised 42 days after intervention and prepared for histological and histomorphometric analysis. All coronary arteries showed complete endothelialization 42 days following treatment. Paclitaxel treatment led to a marked reduction of neointimal proliferation either post stent implantation (neointimal area: 1.04 ± 0.10 mm2 vs. 2.37 ± 0.23 mm2, p<0.001) or post balloon dilatation (neontimal area: 0.35 ± 0.14 mm2, vs. 0.68 ± 0.24 mm2, p<0.01).There were no significant angiographic or histomorphometric differences between the control and the sham group. In both paclitaxel groups neither angiographic edge phenomena nor a significant histomorphometric inflammatory response were found in the treated vessel segments. In conclusion, the local application of paclitaxel via the Genie™ catheter is safe and effective to significantly reduce the proliferative response post-stent implantation or balloon dilatation in an experimental animal model.

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Modeling of Coated Biodegradable Stents

ASME 2012 Summer Bioengineering Conference, Parts A and B ◽

10.1115/sbc2012-80425 ◽

2012 ◽

Author(s):

Nic Debusschere ◽

Matthieu De Beule ◽

Patrick Segers ◽

Benedict Verhegghe ◽

Peter Dubruel

Keyword(s):

Material Model ◽

Local Drug Delivery ◽

Metallic Stent ◽

Biodegradable Stent ◽

Stent Restenosis ◽

Biodegradable Stents ◽

Bioresorbable Stent ◽

Drug Eluting ◽

Corrosion Modelling

A bioresorbable stent supports the stenosed blood vessel during the healing period after coronary angioplasty and then gradually disappears. Unlike permanent stents, the biodegradable stent forms no obstacle for future interventions. Moreover, the degradable stent material presents an ideal vehicle for local drug delivery. Long term side effects inherent to drug eluting stents such as in-stent restenosis and late stent thrombosis might be avoided [1]. To date, several bioresorbable stents are being developed or are currently being tested in clinical trials. Two classes of biomaterials are being used in biodegradable stent technology: biodegradable polymers and bioerodible metal alloys. Polymers can be tailored to have a well-defined degradational behaviour but have relatively poor mechanical properties. Biocorrodible metals such as magnesium alloys have good mechanical characteristics but display a more complex an less predictive degradational behaviour. A biocorrodible metallic stent coated with a biodegradable polymer might be able to combine the benefits of both metallic and polymeric biodegradable stents. Finite element modelling can play an important role in the study of nevel stent designs. To correctly simulate the behaviour of degradable stents a material model must be developed that incorporates the effect of degradation on all material characteristics. In case of a coated biocorrodible magnesium stent this includes corrosion modelling, the effect of the coating and the influence of mechanical loading on the corrosion rate.

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04:03 PM Abstract No. 390 Pharmacokinetic verification of loco-regional delivery of caffeic acid using drug-eluting beads in a large animal model

Journal of Vascular and Interventional Radiology ◽

10.1016/j.jvir.2018.12.465 ◽

2019 ◽

Vol 30 (3) ◽

pp. S171-S172

Author(s):

L. Wilkins ◽

A. Hawrylack ◽

J. Heo ◽

M. Gielata ◽

E. Kubicka ◽

...

Keyword(s):

Animal Model ◽

Caffeic Acid ◽

Large Animal Model ◽

Large Animal ◽

Drug Eluting Beads ◽

Drug Eluting ◽

Regional Delivery

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AS-101: Effect of Hybrid Overlapping Drug-Eluting Stent on Intimal Growth: Animal Model Study

The American Journal of Cardiology ◽

10.1016/j.amjcard.2009.01.150 ◽

2009 ◽

Vol 103 (9) ◽

pp. 46B

Author(s):

Seung Woon Rha ◽

Kang Yin Chen ◽

Yong Jian Li ◽

Kanhaiya Lal Poddar ◽

Yoshiyasu Minami ◽

...

Keyword(s):

Animal Model ◽

Drug Eluting Stent ◽

Model Study ◽

Animal Model Study ◽

Drug Eluting

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Drug-Eluting Beads Loaded with Antiangiogenic Agents for Chemoembolization: In Vitro Sunitinib Loading and Release and In Vivo Pharmacokinetics in an Animal Model

Journal of Vascular and Interventional Radiology ◽

10.1016/j.jvir.2013.11.039 ◽

2014 ◽

Vol 25 (3) ◽

pp. 379-387.e2 ◽

Cited By ~ 19

Author(s):

Katrin Fuchs ◽

Pierre E. Bize ◽

Olivier Dormond ◽

Alban Denys ◽

Eric Doelker ◽

...

Keyword(s):

Animal Model ◽

Antiangiogenic Agents ◽

Drug Eluting Beads ◽

Drug Eluting ◽

In Vivo Pharmacokinetics

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Stenting to prevent esophageal stricture after circumferential endoscopic submucosal dissection: an experimental study

Endoscopy International Open ◽

10.1055/a-1261-3103 ◽

2020 ◽

Vol 08 (11) ◽

pp. E1698-E1706

Author(s):

Jan Martinek ◽

Radek Dolezel ◽

Bara Walterova ◽

Marek Kollar ◽

Stefan Juhas ◽

...

Keyword(s):

Experimental Study ◽

Esophageal Cancer ◽

Endoscopic Submucosal Dissection ◽

Treatment Option ◽

Esophageal Stricture ◽

Drug Eluting Stent ◽

Early Esophageal Cancer ◽

Major Drawback ◽

Biodegradable Stent ◽

Drug Eluting

Abstract Background and study aims Circular ESD (CESD) is a treatment option for patients with extensive early esophageal cancer. Its major drawback is the development of a stricture. Stenting may represent an attractive prevention strategy. We designed an experimental study to assess the effect of stents covered with acellular biomatrix (AB) and a drug-eluting stent. Materials and methods Thirty-five 35 pigs underwent CESD and were randomized into six groups: G1 (control), G2 (SEMS), G3 (SEMS + AB), G4 (SEMS + AB + steroid-eluting layer), G5 (biodegradable stent [BD]), G6 (BD + AB). SEMS were placed alongside the post-CESD defect, fixed and removed after 21 days. The main outcomes were stricture development, severity, and histopathology. Results Pigs with BD stents (G5, 6) experienced severe inflammation and hypergranulation without biodegradation, therefore, these groups were closed prematurely. Significant strictures developed in 29 of 30 pigs (96.7 %). The most severe stricture developed in G2 and G4 (narrowest diameter (mm) 8.5 ± 3, 3 (G2) and 8.6 ± 2.1 (G4) vs. 17 ± 7.3 (G1) and 13.5 ± 8.3 (G3); P < 0.01. Signs of re-epithelization were present in 67 % and 71 % in G1 and G2 and in 100 % in G3 and G4. The most robust re-epithelization layer was present in G4. The inflammation was the most severe in G1 (mean score 2.3) and least severe in G4 (0.4). Conclusions Stenting did not effectively prevent development of post-CESD esophageal stricture. SEMS with AB resulted in improved re-epithelization and decreased stricture severity. Steroid-eluting SEMS suppressed inflammation. BD stents seem inappropriate for this indication.

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