JoVE Logo

Sign In

Mayo Clinic College of Medicine

16 ARTICLES PUBLISHED IN JoVE

image

Biology

Loading Drosophila Nerve Terminals with Calcium Indicators
Adam J. Rossano 1, Gregory T. Macleod 1
1Department of Physiology, University of Texas Health Science Center at San Antonio (UTHSCSA)

Calcium is a ubiquitous messenger in the nervous system, essential for triggering neurotransmitter release and changes in synaptic strength. Here we demonstrate a technique for loading Ca2+-indicators into Drosophila nerve terminals. We also demonstrate fabrication of the required apparatus and emphasize points critical for the technique's success.

image

Immunology and Infection

Isolation of Brain-infiltrating Leukocytes
Reghann G. LaFrance-Corey *1, Charles L. Howe *1
1Department of Neurology, Mayo Clinic College of Medicine

A rapid method to obtain infiltrating leukocytes from the murine brain is described. This method utilizes a continuous Percoll gradient and discontinuous Ficoll gradient to select and purify the leukocyte-enriched layer. Isolated leukocytes may then be characterized by flow cytometric measurements.

image

Biology

Immunostaining of Dissected Zebrafish Embryonic Heart
Jingchun Yang 1, Xiaolei Xu 1
1Division of Cardiovascular Diseases, Department of Biochemistry and Molecular Biology, Mayo Clinic College of Medicine

A rapid way to conduct immunostaining of zebrafish embryonic heart is described. Compared to the whole mount immunostaining approach, this method dramatically increases the penetration of the antibodies, which allows obtaining high resolution images that reveal cellular/subcellular structures in the heart within a much reduced processing time.

image

Neuroscience

Heat-Induced Antigen Retrieval: An Effective Method to Detect and Identify Progenitor Cell Types during Adult Hippocampal Neurogenesis
Syed M.Q. Hussaini *1, Heechul Jun *1, Chang Hoon Cho 1, Hyo Jin Kim 1, Woon Ryoung Kim 2, Mi-Hyeon Jang 1,3
1Department of Neurologic Surgery, Mayo Clinic College of Medicine, 2Department of Anatomy, Korea University College of Medicine, 3Department of Biochemistry and Molecular Biology, Mayo Clinic College of Medicine

During adult hippocampal neurogenesis, a distinct set of genetic markers are expressed when a quiescent neural stem cell sequentially progresses and develops into a functionally integrated neuron in the circuit. Using heat-induced antigen retrieval, progenitor cell types that are otherwise difficult to detect are identified with improved effectiveness.

image

Bioengineering

Formation of Biomembrane Microarrays with a Squeegee-based Assembly Method
Nathan J. Wittenberg 1, Timothy W. Johnson 1, Luke R. Jordan 2, Xiaohua Xu 3, Arthur E. Warrington 3, Moses Rodriguez 3,4, Sang-Hyun Oh 1,2
1Department of Electrical and Computer Engineering, University of Minnesota, 2Department of Biomedical Engineering, University of Minnesota, 3Department of Neurology, Mayo Clinic College of Medicine, 4Department of Immunology, Mayo Clinic College of Medicine

Supported lipid bilayers and natural membrane particles are convenient systems that can approximate the properties of cell membranes and be incorporated in a variety of analytical strategies. Here we demonstrate a method for preparing microarrays composed of supported lipid bilayer-coated SiO2 beads, phospholipid vesicles or natural membrane particles.

image

Bioengineering

Cell Labeling and Targeting with Superparamagnetic Iron Oxide Nanoparticles
Brandon J. Tefft 1, Susheil Uthamaraj 2, J. Jonathan Harburn 3, Martin Klabusay 4, Dan Dragomir-Daescu 2,5, Gurpreet S. Sandhu 1
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.

image

Bioengineering

Ferromagnetic Bare Metal Stent for Endothelial Cell Capture and Retention
Susheil Uthamaraj 1, Brandon J. Tefft 2, Ota Hlinomaz 3, Gurpreet S. Sandhu 2, 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.

image

Immunology and Infection

Antibody Binding Specificity for Kappa (Vκ) Light Chain-containing Human (IgM) Antibodies: Polysialic Acid (PSA) Attached to NCAM as a Case Study
Jens O. Watzlawik 1,2,3, Robert J. Kahoud 1,3,5, Bharath Wootla 1,2,3, Meghan M. Painter 1,2,3, Arthur E. Warrington 1,2,3, William A. Carey 3,4, Moses Rodriguez 1,2,3
1Department of Neurology, Mayo Clinic, 2Mayo Clinic Center for Multiple Sclerosis and Autoimmune Neurology, Mayo Clinic, 3Center for Regenerative Medicine, Neuroregeneration, Mayo Clinic, 4Division of Neonatal Medicine, Mayo Clinic, 5Department of Pediatric and Adolescent Medicine, Mayo Clinic

We present a protocol to identify protein moieties containing antigens for human and mouse IgM antibodies with specific kappa (Vκ) light chains. This protocol is not limited to IgM class antibodies but applies to all immunoglobulin isotypes that target their antigen with sufficiently high affinity during immunoprecipitations.

image

Medicine

Fabrication of Small Caliber Stent-grafts Using Electrospinning and Balloon Expandable Bare Metal Stents
Susheil Uthamaraj 1, Brandon J. Tefft 2, Soumen Jana 2, Ota Hlinomaz 3, Manju Kalra 4, Amir Lerman 2, Dan Dragomir-Daescu 1,5, Gurpreet S. Sandhu 2
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.

image

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 Uthamaraj 2, Timothy Rossman 2, James T. Bronk 3, Mark Bolander 3, Vincent Lambert 2, Sean McEligot 2, Rachel Entwistle 2, Hugo Giambini 3, Iwona Jasiuk 4, Michael J. Yaszemski 3, 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.

image

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 Rossman 2, Susheil Uthamaraj 2, Rachel Entwistle 2, Sean McEligot 2, Vincent Lambert 2, Hugo Giambini 3, Iwona Jasiuk 4, Michael J. Yaszemski 3, 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

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.

image

Bioengineering

A Method to Estimate Cadaveric Femur Cortical Strains During Fracture Testing Using Digital Image Correlation
Timothy Rossman 1, Susheil Uthamaraj 1, Asghar Rezaei 1,2, Sean McEligot 1, Hugo Giambini 3, Iwona Jasiuk 4, Michael J. Yaszemski 3, Lichun Lu 3, 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.

image

Immunology and Infection

MicroRNA-based Regulation of Picornavirus Tropism
Autumn J. Ruiz 1, Stephen J. Russell 1
1Department of Molecular Medicine, Mayo Clinic College of Medicine

We describe here a method for regulating picornavirus tropism by incorporating sequences complementary to specific microRNAs into the viral genome. This protocol can be adapted to all different classes of viruses with modifications based upon the length and nature of their life cycle.

image

Biology

Optical Quantification of Intracellular pH in Drosophila melanogaster Malpighian Tubule Epithelia with a Fluorescent Genetically-encoded pH Indicator
Adam J. Rossano 1, Michael F. Romero 1,2
1Department of Physiology and Biomedical Engineering, Mayo Clinic College of Medicine, 2Department of Nephrology and Hypertension, Mayo Clinic College of Medicine

Cellular ion transport can often be assessed by monitoring intracellular pH (pHi). Genetically Encoded pH-Indicators (GEpHIs) provide optical quantification of intracellular pH in intact cells. This protocol details the quantification of intracellular pH through cellular ex vivo live-imaging of Malpighian tubules of Drosophila melanogaster with pHerry, a pseudo-ratiometric genetically encoded pH-indicator.

image

Medicine

A Doxorubicin-induced Cardiomyopathy Model in Adult Zebrafish
Xiao Ma *1,2,3, Yonghe Ding *2,3, Yong Wang 2,3,4, Xiaolei Xu 1,2,3
1Clinical and Translational Sciences Track, Mayo Clinic Graduate School of Biomedical Sciences, 2Department of Biochemistry and Molecular Biology, Mayo Clinic, 3Division of Cardiovascular Diseases, Mayo Clinic, 4Institute of Life Science, Beijing University of Chinese Medicine

A method to generate a doxorubicin-induced cardiomyopathy model in adult zebrafish (Danio rerio) is described here. Two alternative ways of intraperitoneal injection are presented and conditions to reduce variations among different experimental groups are discussed.

image

Medicine

Use of 3D Robotic Ultrasound for In Vivo Analysis of Mouse Kidneys
Heather L. Holmes *1, Alison A. Stiller *1, Christopher J. Moore 4, Adriana V. Gregory 2, Carolyn M. Roos 3, Jordan D. Miller 1,3, Ryan C. Gessner 4, Tomasz J. Czernuszewicz 4, Timothy L. Kline 2, Michael F. Romero 1,5
1Physiology & Biomedical Engineering, Mayo Clinic, 2Radiology, Mayo Clinic, 3Surgery, Mayo Clinic, 4SonoVol, Inc., 5Nephrology & Hypertension, Mayo Clinic

This protocol demonstrates robotic ultrasound (US) as a practical, cost-effective, and quick alternative to traditional non-invasive image modalities.

JoVE Logo

Privacy

Terms of Use

Policies

Research

Education

ABOUT JoVE

Copyright © 2024 MyJoVE Corporation. All rights reserved