1
|
Morand J, McClellan P, Isali I, Dikici Y, Fan D, Li L, Shoffstall AJ, Akkus O, Weidenbecher M. Dexamethasone eluting polydopaminated polycaprolactone-poly (lactic-co-glycolic) acid for treatment of tracheal stenosis. J Biomed Mater Res A 2024; 112:781-792. [PMID: 38204293 DOI: 10.1002/jbm.a.37659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Revised: 12/06/2023] [Accepted: 12/08/2023] [Indexed: 01/12/2024]
Abstract
Tracheal stenosis is commonly caused by injury, resulting in inflammation and fibrosis. Inhibiting inflammation and promoting epithelization can reduce recurrence after initial successful treatment of tracheal stenosis. Steroids play an important role in tracheal stenosis management. This study in vitro evaluated effectiveness of a polydopaminated polycaprolactone stent coated with dexamethasone-eluting poly(lactic-co-glycolic) acid microparticles (μPLGA) for tracheal stenosis management. Polydopamination was characterized by Raman spectroscopy and promoted epithelialization while dexamethasone delivery reduced macrophage activity, assessed by individual cell area measurements and immunofluorescent staining for inducible nitric oxide synthase (iNOS). Dexamethasone release was quantified by high-performance liquid chromatography over 30 days. Activation-related increase in cell area and iNOS production by RAW 264.7 were both reduced significantly (p < .05) through dexamethasone release. Epithelial cell spreading was higher on polydopaminated polycaprolactone (PCL) than PCL-alone (p < .05). Force required for stent migration was measured by pullout tests of PCL-μPLGA stents from cadaveric rabbit and porcine tracheas (0.425 ± 0.068 N and 1.082 ± 0.064 N, respectively) were above forces estimated to occur during forced respiration. Biomechanical support provided by stents to prevent airway collapse was assessed by comparing compressive circumferential stiffness, and stiffness of the stent was about 1/10th of the rabbit trachea (0.156 ± 0.023 N/mm vs. 1.420 ± 0.194 N/mm, respectively). A dexamethasone-loaded PCL-μPLGA stent platform can deliver dexamethasone and exhibits sufficient mechanical properties to anchor within the trachea and polydopamination of PCL is conducive to epithelial layer formation. Therefore, a polydopaminated PCL-μPLGA stent is a promising candidate for in vivo evaluation for treatment of tracheal restenosis.
Collapse
Affiliation(s)
- Jacob Morand
- Advanced Platform Center, Louis Stokes Cleveland Veteran Affairs Medical Center, Cleveland, Ohio, USA
| | - Phillip McClellan
- Department of Urology, Case Western Reserve University, Cleveland, Ohio, USA
| | - Ilaha Isali
- Department of Urology, Case Western Reserve University, Cleveland, Ohio, USA
| | - Yusuf Dikici
- Department of Mechanical and Aerospace Engineering, Case Western Reserve University, Cleveland, Ohio, USA
| | - Di Fan
- Department of Mechanical and Aerospace Engineering, Case Western Reserve University, Cleveland, Ohio, USA
| | - Longshun Li
- Advanced Platform Center, Louis Stokes Cleveland Veteran Affairs Medical Center, Cleveland, Ohio, USA
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio, USA
| | - Andrew J Shoffstall
- Advanced Platform Center, Louis Stokes Cleveland Veteran Affairs Medical Center, Cleveland, Ohio, USA
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio, USA
| | - Ozan Akkus
- Department of Mechanical and Aerospace Engineering, Case Western Reserve University, Cleveland, Ohio, USA
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, Ohio, USA
- Department of Orthopedic Surgery, University Hospitals Cleveland Medical Center, Cleveland, Ohio, USA
| | - Mark Weidenbecher
- Advanced Platform Center, Louis Stokes Cleveland Veteran Affairs Medical Center, Cleveland, Ohio, USA
- Department of Otolaryngology, Case Western Reserve University, Cleveland, Ohio, USA
| |
Collapse
|
2
|
Dikici Y, Daltorio KA, Akkus O. Nodes for modes: nodal honeycomb metamaterial enables a soft robot with multimodal locomotion. Bioinspir Biomim 2024. [PMID: 38631362 DOI: 10.1088/1748-3190/ad3ff8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/19/2024]
Abstract
Soft-bodied animals, such as worms and snakes, use many muscles in different ways to traverse unstructured environments and inspire tools for accessing confined spaces. They demonstrate versatility of locomotion which is essential for adaptation to changing terrain conditions. However, replicating such versatility in untethered soft-bodied robots with multimodal locomotion capabilities have been challenging due to complex fabrication processes and limitations of soft body structures to accommodate hardware such as actuators, batteries and circuit boards. Here, we present MetaCrawler, a 3D printed metamaterial soft robot designed for multimodal and omnidirectional locomotion. Our design approach facilitated an easy fabrication process through a discrete assembly of a modular nodal honeycomb lattice with soft and hard components. A crucial benefit of the nodal honeycomb architecture is the ability of its hard components, nodes, to accommodate a distributed actuation system, comprising servomotors, control circuits, and batteries. Enabled by this distributed actuation, MetaCrawler achieves five locomotion modes: peristalsis, sidewinding, sideways translation, turn-in-place, and anguilliform. Demonstrations showcase MetaCrawler's adaptability in confined channel navigation, vertical traversing, and maze exploration. This soft robotic system holds the potential to offer easy-to-fabricate and accessible solutions for multimodal locomotion in applications such as search and rescue, pipeline inspection, and space missions.
Collapse
Affiliation(s)
- Yusuf Dikici
- Department of Mechanical & Aerospace Engineering, Case Western Reserve University Case School of Engineering, 10900 Euclid Avenue, Cleveland, Ohio, 44106, UNITED STATES
| | - Kathryn A Daltorio
- Department of Mechanical & Aerospace Engineering, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, Ohio, 44106, UNITED STATES
| | - Ozan Akkus
- Department of Mechanical & Aerospace Engineering, Case Western Reserve University Case School of Engineering, 10900 Euclid Avenue, Cleveland, Ohio, 44106, UNITED STATES
| |
Collapse
|