Mayo Clinic College of Medicine, Mayo Clinic

7 ARTICLES PUBLISHED IN JoVE

Bioengineering

Cell Labeling and Targeting with Superparamagnetic Iron Oxide Nanoparticles

Brandon J. Tefft¹, Susheil Uthamaraj², J. Jonathan Harburn³, Martin Klabusay⁴, Dan Dragomir-Daescu^2,5, Gurpreet S. Sandhu¹

¹Division of Cardiovascular Diseases, Mayo Clinic, ²Division of Engineering, Mayo Clinic, ³School of Medicine, Pharmacy and Health, Durham University, ⁴Regional Center for Applied Molecular Oncology, Masaryk Memorial Cancer Institute, ⁵Mayo Clinic College of Medicine, Mayo Clinic

Targeted cell delivery is useful in a variety of biomedical applications. The goal of this protocol is to use superparamagnetic iron oxide nanoparticles (SPION) to label cells and thereby enable magnetic cell targeting approaches for a high degree of control over cell delivery and localization.

Bioengineering

Ferromagnetic Bare Metal Stent for Endothelial Cell Capture and Retention

Susheil Uthamaraj¹, Brandon J. Tefft², Ota Hlinomaz³, Gurpreet S. Sandhu², Dan Dragomir-Daescu^1,4

¹Division of Engineering, Mayo Clinic, ²Division of Cardiovascular Diseases, Mayo Clinic, ³Department of Cardioangiology, ICRC, St. Anne's University Hospital, ⁴Mayo Clinic College of Medicine

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.

Medicine

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

Susheil Uthamaraj¹, Brandon J. Tefft², Soumen Jana², Ota Hlinomaz³, Manju Kalra⁴, Amir Lerman², Dan Dragomir-Daescu^1,5, Gurpreet S. Sandhu²

¹Division of Engineering, Mayo Clinic, ²Department of Cardiovascular Diseases, Mayo Clinic, ³Department of Cardioangiology, ICRC, St. Anne's University Hospital, ⁴Department of Vascular Surgery, Mayo Clinic, ⁵Department of Physiology and Biomedical Engineering, 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.

Medicine

Proximal Cadaveric Femur Preparation for Fracture Strength Testing and Quantitative CT-based Finite Element Analysis

Dan Dragomir-Daescu^1,2, Asghar Rezaei^1,2, Susheil Uthamaraj², Timothy Rossman², James T. Bronk³, Mark Bolander³, Vincent Lambert², Sean McEligot², Rachel Entwistle², Hugo Giambini³, Iwona Jasiuk⁴, Michael J. Yaszemski³, Lichun Lu^1,3

¹Department of Physiology and Biomedical Engineering, Mayo Clinic, ²Division of Engineering, Mayo Clinic, ³Department of Orthopedic Surgery, Mayo Clinic, ⁴Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign

We present a robust protocol on how to carefully preserve and prepare cadaveric femora for fracture testing and quantitative computed tomography imaging. The method provides precise control over input conditions for the purpose of determining relationships between bone mineral density, fracture strength, and defining finite element model geometry and properties.

JoVE Core

Method and Instrumented Fixture for Femoral Fracture Testing in a Sideways Fall-on-the-Hip Position

Dan Dragomir-Daescu^1,2, Asghar Rezaei^1,2, Timothy Rossman², Susheil Uthamaraj², Rachel Entwistle², Sean McEligot², Vincent Lambert², Hugo Giambini³, Iwona Jasiuk⁴, Michael J. Yaszemski³, Lichun Lu^1,3

In this manuscript, we present a protocol to fracture test cadaveric proximal femora in a sideways fall on the hip configuration using instrumented fixtures mounted on a standard servo hydraulic frame. Nine digitized signals comprising forces, moments, and displacement along with two high speed video streams are acquired during testing.

Bioengineering

A Method to Estimate Cadaveric Femur Cortical Strains During Fracture Testing Using Digital Image Correlation

Timothy Rossman¹, Susheil Uthamaraj¹, Asghar Rezaei^1,2, Sean McEligot¹, Hugo Giambini³, Iwona Jasiuk⁴, Michael J. Yaszemski³, Lichun Lu³, Dan Dragomir-Daescu^1,2

¹Division of Engineering, Mayo Clinic, ²Department of Physiology and Biomedical Engineering, Mayo Clinic, ³Department of Orthopedic Surgery, Mayo Clinic, ⁴Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign

In this protocol, the femur surface strains are estimated during fracture testing using the digital image correlation technique. The novelty of the method involves application of a high-contrast stochastic speckle pattern on the femur surface, carefully specified illumination, high speed video capture, and digital image correlation analysis for strain calculations.

Synthesis and Characterization of Charged Hydrogels for the Extended Delivery of Vancomycin

Carl T. Gustafson¹, Felix Boakye-Agyeman², Cassandra L. Brinkman³, Joel M. Reid¹, Robin Patel³, Zeljko Bajzer^4,5, Mahrokh Dadsetan⁵, Michael J. Yaszemski^5,6,1

¹Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Graduate School, Mayo Clinic College of Medicine, Mayo Clinic, ²Pharmacometrics Center, Duke Clinical Research Institute, ³Department of Laboratory Medicine and Pathology, Mayo Clinic, ⁴Department of Biochemistry and Molecular Biology, Mayo Clinic College of Medicine, Mayo Clinic, ⁵Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine, Mayo Clinic, ⁶Department of Orthopedic Surgery, Mayo Graduate School, Mayo Clinic College of Medicine, Mayo Clinic

Here we describe the synthesis and use of oligo(poly(ethylene glycol)fumarate) / sodium methacrylate (OPF/SMA) charged copolymers as an affinity based delivery system for vancomycin.