JoVE Clinical and Translational Medicine
Remote Magnetic Navigation for Accurate, Real-time Catheter Positioning and Ablation in Cardiac Electrophysiology Procedures
1Cardiology, Robotic Cardiac Electrophysiology and Arrhythmia Unit, La Paz University Hospital, 2Magnetecs Corp., 3Cardiology, Geffen School of Medicine at UCLA Los Angeles
This report provides a detailed description of a new remote navigation system based on magnetic driven forces, which has been recently introduced as a new robotic tool for human cardiac electrophysiology procedures.
JoVE Clinical and Translational Medicine
Mouse Eye Enucleation for Remote High-throughput Phenotyping
1Department of Ophthalmology and Visual Sciences, University of Iowa, 2Omics Laboratory, University of Iowa, 3School of Dentistry, UCLA, 4Bernard and Shirlee Brown Glaucoma Laboratory, Department of Ophthalmology, College of Physicians and Surgeons, Columbia University
The dissection technique illustrates enucleation of the mouse eye for tissue fixation to perform phenotyping in high-throughput screens.
JoVE Neuroscience
Eye Movement Monitoring of Memory
1Rotman Research Institute, 2Department of Psychology, University of Toronto, 3Department of Psychiatry, University of Toronto
Eye movement monitoring (or eye tracking) reveals where in space the eyes linger, when and for how long. Here, we demonstrate how eye tracking can be used to investigate the integrity of memory in multiple participant populations, without requiring verbal, or otherwise explicit, reports.
JoVE Bioengineering
Magnetically-Assisted Remote Controlled Microcatheter Tip Deflection under Magnetic Resonance Imaging
1Department of Radiology and Biomedical Imaging, University of California, San Francisco, 2School of Medicine, University of California, San Francisco, 3Department of Radiology and Biomedical Imaging, UCSF Medical Center, 4University of California, San Francisco, 5Hansen Medical, Mountain View, CA
Current applied to an endovascular microcatheter with microcoil tip made by laser lathe lithography can achieve controllable deflections under magnetic resonance (MR) guidance, which may improve speed and efficacy of navigation of vasculature during various endovascular procedures.
JoVE Neuroscience
Scalable Fluidic Injector Arrays for Viral Targeting of Intact 3-D Brain Circuits
Controlling and analyzing neural circuits in vivo would be facilitated by a technology for delivery of viruses and other reagents to desired 3-dimensional sets of brain regions. We demonstrate customized fluidic injector array fabrication, and delivery of virally-encoded optical sensitizers, enabling optical manipulation of complex brain circuits.
JoVE Clinical and Translational Medicine
Acute and Chronic Tactile Sensory Testing after Spinal Cord Injury in Rats
1Center for Brain and Spinal Cord Repair, School of Allied Medical Professions, The Ohio State University, 2Spinal Cord Research Center, Drexel University College of Medicine
We describe two tactile sensory testing methods for acute or chronic periods of spinal cord injury in rats. These validated procedures can detect the development and maintenance of allodynia-like sensations.
JoVE Immunology and Infection
Rapid Diagnosis of Avian Influenza Virus in Wild Birds: Use of a Portable rRT-PCR and Freeze-dried Reagents in the Field
1USGS Western Ecological Research Center, 2Wildlife Health Center, University of California, Davis, 3Department of Population Health and Reproduction, University of California, Davis, 4Department of Veterinary and Biomedical Sciences, University of Minnesota, 5Science Applications International Corporation
This study describes diagnosis of avian influenza in wild birds using a portable rRT-PCR system. The method takes advantage of freeze-dried reagents to screen wild birds in a non-laboratory setting, typical of an outbreak scenario. Use of molecular tools provides accurate and sensitive alternatives for rapid diagnosis.
JoVE General
Micro-drive Array for Chronic in vivo Recording: Drive Fabrication
1Picower Institute for Learning and Memory, MIT - Massachusetts Institute of Technology, 2Department of Brain and Cognitive Science, MIT - Massachusetts Institute of Technology
In this protocol we demonstrate how to fabricate a micro-drive array for chronic electrophysiological recordings in rats.
JoVE General
Elevated Plus Maze for Mice
1Genetic Engineering and Functional Genomics Unit, Frontier Technology Center, Graduate School of Medicine, Kyoto University, 2Institute for Comprehensive Medical Science Division of Systems Medicine, Fujita Health University
The elevated plus maze test is one of the most widely used tests for measuring anxiety-like behavior in mice. Here, we present a movie showing the detailed procedures for conducting the test.
JoVE General
Procedure for Fabricating Biofunctional Nanofibers
1Department of Chemistry, Clark Atlanta University, 2Department of Physics, Clark Atlanta University, 3Department of Chemistry and Chemical Biology, Cornell University
An efficient approach for preparing nanofibers decorated with functional groups capable of specifically interacting with proteins is described. The approach first requires the preparation of a polymer functionalized with the appropriate functional group. The functional polymer is fabricated into nanofibers by electrospinning. The effectiveness of the binding of the nanofibers with a protein is studied by confocal microscopy.
JoVE General
A Noninvasive Hair Sampling Technique to Obtain High Quality DNA from Elusive Small Mammals
We present a noninvasive sampling approach to efficiently collect hair samples from elusive small mammals, as shown for the American pika. We demonstrate the utility of this method by extracting DNA from sampled hair and amplifying several types of molecular markers commonly used in studies of wildlife ecology and conservation.
JoVE Clinical and Translational Medicine
Pseudofracture: An Acute Peripheral Tissue Trauma Model
1Department of Surgery, University of Pittsburgh, 2Department of Orthopedic Surgery, University of Aachen Medical Center
Pseudofracture, a reproducible murine model of sterile musculoskeletal trauma, allows for evaluation of late term post-traumatic immune responses. This article describes the procedural execution of the model step by step, including the potential for experimental model combinations to permit study of multiple trauma.
JoVE Neuroscience
Brain Imaging Investigation of the Neural Correlates of Emotional Autobiographical Recollection
1Department of Psychiatry, University of Alberta, Edmonton, 2Psychology Department, University of Illinois, Urbana-Champaign, 3Neuroscience Program, University of Illinois, Urbana-Champaign, 4Beckman Institute for Advanced Science & Technology, University of Illinois, Urbana-Champaign
We present a protocol that allows investigation of the neural correlates of recollecting emotional autobiographical memories, using functional magnetic resonance imaging. This protocol can be used with both healthy and clinical participants.
JoVE Clinical and Translational Medicine
A Murine Closed-chest Model of Myocardial Ischemia and Reperfusion
1Department of Anesthesiology and Intensive Care Medicine, University of Bonn, Germany, 2Institute of Physiology, University of Bonn, Germany
Surgical trauma induces an inflammatory response. Cytokines and endogenous ligands are known to modulate myocardial infarct size following ischemia and reperfusion. We present a modified closed-chest model of murine ischemia and reperfusion using hanging weights to minimize effects of thoracotomy.
JoVE General
Electricity-Free, Sequential Nucleic Acid and Protein Isolation
1CUBRC, Inc., 2Department of Microbiology and Immunology, State University of New York at Buffalo, School of Medicine and Biomedical Sciences
A tool and chemistries are described to sequentially isolate nucleic acids followed by proteins from a sample without the need for electricity. The tool consists of a sorbent held within a transfer pipette while the isolation chemistries are based on solid-phase extraction principles. The isolated macromolecules can be analyzed by immuno-based and PCR-based assays.
JoVE Applied Physics
Dry Oxidation and Vacuum Annealing Treatments for Tuning the Wetting Properties of Carbon Nanotube Arrays
Graduate Aeronautical Laboratories, California Institute of Technology
This article describes a simple method to fabricate vertically aligned carbon nanotube arrays by CVD and to subsequently tune their wetting properties by exposing them to vacuum annealing or dry oxidation treatment.
JoVE Clinical and Translational Medicine
Methods for ECG Evaluation of Indicators of Cardiac Risk, and Susceptibility to Aconitine-induced Arrhythmias in Rats Following Status Epilepticus
Department of Pharmacology and Toxicology, University of Utah
Techniques for measurement of electrical activity of the heart by electrocardiogram (ECG), and analysis of cardiac risk factors and susceptibility to arrhythmias following status epilepticus (SE) in the rat are described.
JoVE Bioengineering
High-resolution Fiber-optic Microendoscopy for in situ Cellular Imaging
1Department of Bioengineering, Rice University, 2Department of Molecular and Cellular Oncology, The Univeristy of Texas M. D. Anderson Cancer Center
In many biological and clinical situations it is advantageous to study cellular processes as they evolve in their native microenvironment. Here we describe the assembly and use of a low-cost fiber-optic microscope which can provide real time imaging in cell culture, animal studies, and clinical patient studies.
JoVE Neuroscience
Simultaneous Recording of Calcium Signals from Identified Neurons and Feeding Behavior of Drosophila melanogaster
Department of Neurobiology, University of Massachusetts Medical School
The fruit fly, Drosophila melanogaster, extends its proboscis for feeding, responding to a sugar stimulus from its proboscis or tarsus. I have combined observations of the proboscis extension response (PER) with a calcium imaging technique, allowing us to monitor the activity of neurons in the brain, simultaneously with behavioral observation.
JoVE Clinical and Translational Medicine
Method to Measure Tone of Axial and Proximal Muscle
1Department of Biomedical Engineering, Oregon Health and Science University, 2UCL Institute of Neurology, Queen Square, 3Department of Neurology, Oregon Health and Science University
We have developed a device (Twister) to study the regulation of tonic muscle activity during active postural maintenance. Twister measures torsional resistance and muscular responses in standing subjects during twisting of the body axis. The device can be flexibly configured to study various aspects of tonic control across the neck, trunk, and/or hips.
JoVE Clinical and Translational Medicine
Use of a Hanging-weight System for Liver Ischemia in Mice
1UCH Transplant Center, University of Colorado, Denver, 2Department of Anesthesiology, University of Colorado, Denver
We established a novel murine model of a hanging weight system for portal triad occlusion. This technique may be useful for future investigations of ischemia in murine hepatic models.
JoVE Bioengineering
Hollow Microneedle-based Sensor for Multiplexed Transdermal Electrochemical Sensing
1Joint Department of Biomedical Engineering, University of North Carolina and North Carolina State University, 2Department of Biosensors and Nanomaterials, Sandia National Laboratories
This article details the construction of a multiplexed microneedle-based sensor. The device is being developed for in situ sampling and electrochemical analysis of multiple analytes in a rapid and selective manner. We envision clinical medicine and biomedical research uses for these microneedle-based sensors.
JoVE Immunology and Infection
Glass Wool Filters for Concentrating Waterborne Viruses and Agricultural Zoonotic Pathogens
1Wisconsin Water Science Center, United States Geological Survey, 2University of Wisconsin – Madison, 3Agricultural Research Service, United States Department of Agriculture, 4Alaska Science Center, United States Geological Survey
Glass wool filters have been used to concentrate waterborne viruses by a number of research groups around the world. Here we show a simple approach for constructing glass wool filters and demonstrate the filters are also effective in concentrating waterborne viral, bacterial and protozoan pathogens.
JoVE Applied Physics
Polycrystalline Silicon Thin-film Solar cells with Plasmonic-enhanced Light-trapping
School of Photovoltaics, University of New South Wales
Polycrystalline silicon thin-film solar cells on glass are fabricated by deposition of boron and phosphorous doped silicon layers followed by crystallisation, defect passivation and metallisation. Plasmonic light-trapping is introduced by forming Ag nanoparticles on the silicon cell surface capped with a diffused reflector resulting in ~45% photocurrent enhancement.
JoVE Neuroscience
Voltage-sensitive Dye Recording from Axons, Dendrites and Dendritic Spines of Individual Neurons in Brain Slices
Department of Cellular and Molecular Physiology, Yale University School of Medicine
An imaging technique for monitoring of membrane potential changes with sub-micrometer spatial and sub-millisecond temporal resolution is described. The technique, based on laser excitation of voltage-sensitive dyes, allows measurements of signals in axons and axon collaterals, terminal dendritic branches, and individual dendritic spines.
JoVE Immunology and Infection
Isolation of Fidelity Variants of RNA Viruses and Characterization of Virus Mutation Frequency
Viral Populations and Pathogenesis lab and CNRS 3015, Institut Pasteur
The present article describes the steps required to isolate and characterize RNA polymerase fidelity variants of RNA viruses and how to use mutation frequency data to confirm fidelity changes in tissue culture.
JoVE Neuroscience
Combining Computer Game-Based Behavioural Experiments With High-Density EEG and Infrared Gaze Tracking
1Department of Human Development, Cornell University, 2Social Sciences Division, University of Chicago, 3National Brain Research Centre, Manesar, India
Procedures for recording high-density EEG and gaze data during computer game-based cognitive tasks are described. Using a video game to present cognitive tasks enhances ecological validity without sacrificing experimental control.
JoVE General
Primary Human Bronchial Epithelial Cells Grown from Explants
Medicine, Faculty of Health Sciences, McMaster University
Here we describe a detailed method for growing primary human bronchial epithelial cells from explants of human bronchial airway tissue including differentiated growth on an air-liquid interface. This method provides an abundant source of primary cells for investigating the role of the airway epithelium in human lung health and disease.
JoVE Clinical and Translational Medicine
Use of a Hanging Weight System for Coronary Artery Occlusion in Mice
Department of Anesthesiology, University of Colorado Denver
A murine model for myocardial ischemia and ischemic preconditioning is an important tool study cardioprotective mechanisms in vivo. Here, we report an easy applicable in situ model for cardiac IP using a hanging-weight system for coronary artery occlusion.
JoVE Immunology and Infection
Determination of Molecular Structures of HIV Envelope Glycoproteins using Cryo-Electron Tomography and Automated Sub-tomogram Averaging
1Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 2The Medical Research Council Mitochondrial Biology Unit, University of Cambridge, 3National Library of Medicine, National Institutes of Health, 4Massachusetts Institute of Technology, 5William Fremd High School, 6University of Virginia, 7Duke University, 8Yale University, 9University of Notre Dame, 10Washington University in St. Louis, 11Bioinformatics and Computational Biosciences Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 12Thomas Jefferson High School for Science and Technology
The protocol describes a high-throughput approach to determining structures of membrane proteins using cryo-electron tomography and 3D image processing. It covers the details of specimen preparation, data collection, data processing and interpretation, and concludes with the production of a representative target for the approach, the HIV-1 Envelope glycoprotein. These computational procedures are designed in a way that enables researchers and students to work remotely and contribute to data processing and structural analysis.
JoVE Neuroscience
Design and Assembly of an Ultra-light Motorized Microdrive for Chronic Neural Recordings in Small Animals
1Center for Brain Science, Harvard University, 2Program in Neuroscience, Harvard University, 3Department of Organismic and Evolutionary Biology, Harvard University
The design, fabrication and assembly of an ultra-light motorized microdrive is described. The device provides a cost-effective and easy-to-use solution for chronic recordings of single units in small behaving animals.
JoVE Clinical and Translational Medicine
Reduction in Left Ventricular Wall Stress and Improvement in Function in Failing Hearts using Algisyl-LVR
1Department of Surgery, UCSF/VA Medical Center, 2Clinical & Regulatory, LoneStar Heart, Inc.
This article describes procedures for implanting a novel hydrogel in failing hearts and quantifying its effect on left ventricular wall stress and function. These procedures have been successfully applied in dogs and humans.
JoVE Immunology and Infection
Avian Influenza Surveillance with FTA Cards: Field Methods, Biosafety, and Transportation Issues Solved
1Resource Ecology Group, Wageningen University, 2Section for Zoonotic Ecology and Epidemiology, School of Natural Sciences, Linnaeus University, 3Centre for Wildlife Ecology, Simon Fraser University
A method to preserve, detect and sequence RNA from Avian Influenza Viruses was validated and extended using natural faecal samples from birds. This technique removes the necessity of maintaining a cool chain and handling of infectious viruses and can be applied in a 96-well high-throughput setup.
JoVE Bioengineering
Registered Bioimaging of Nanomaterials for Diagnostic and Therapeutic Monitoring
1Department of Radiology, University of Nebraska Medical Center, 2Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center
Bioimaging methods used to assess cell biodistribution of nanoparticles are applicable for therapeutic and diagnostic monitoring of nanoformulated compounds. The methods described herein are sensitive and specific when assessed by histological coregistration. The methodologies provide a translational pathway from rodent to human applications.
JoVE Clinical and Translational Medicine
Eye Tracking Young Children with Autism
1School of Behavioral and Brain Sciences, University of Texas at Dallas, 2Carolina Institute for Developmental Disabilities, School of Medicine, University of North Carolina at Chapel Hill
Eye tracking has long been used to study gaze patterns in typically-developing individuals, but recent technological advancements have made its use with clinical populations, including autism, more feasible. While eye-tracking young children with autism can offer insight into early symptom manifestations, it involves methodological challenges. Suggestions for best practices are provided.
JoVE Neuroscience
Rapid Determination of the Thermal Nociceptive Threshold in Diabetic Rats
1Department of Pharmacology and Toxicology, Wright State University, 2Human Movement Laboratory, Universidade São Judas Tadeu
Here, we describe a rapid reliable and simple procedure to determine the lowest temperature at which rats or mice show nocifensive behavior, i.e. the thermal nociceptive threshold (TNT). This method applies a slowly increasing thermal stimulus allowing precise and reproducible estimation of TNTs with minimum, if any, stress to the animals.
JoVE Immunology and Infection
Monitoring Dendritic Cell Migration using 19F / 1H Magnetic Resonance Imaging
1Experimental and Clinical Research Center, A joint cooperation between the Charité Medical Faculty and the Max Delbrück Center for Molecular Medicine, 2Berlin Ultrahigh Field Facility (B.U.F.F.), Max Delbrück Center for Molecular Medicine
Tracking of cells using MRI has gained remarkable attention in the past years. This protocol describes the labeling of dendritic cells with fluorine (19F)-rich particles, the in vivo application of these cells, and monitoring the extent of their migration to the draining lymph node with 19F/1H MRI and 19F MRS.
JoVE Neuroscience
Optogenetic Activation of Zebrafish Somatosensory Neurons using ChEF-tdTomato
Department of Molecular, Cell, and Developmental Biology, University of California, Los Angeles
Optogenetic techniques have made it possible to study the contribution of specific neurons to behavior. We describe a method in larval zebrafish for activating single somatosensory neurons expressing a channelrhodopsin variant (ChEF) with a diode-pumped solid state (DPSS) laser and recording the elicited behaviors with a high-speed video camera.
JoVE Bioengineering
Three-dimensional Cell Culture Model for Measuring the Effects of Interstitial Fluid Flow on Tumor Cell Invasion
School of Biomedical Engineering, Science and Health Systems, Drexel University
Interstitial fluid flow is elevated in solid tumors and can modulate tumor cell invasion. Here we describe a technique to apply interstitial fluid flow to cells embedded in a matrix and then measure its effects on cell invasion. This technique can be easily adapted to study other systems.
JoVE Clinical and Translational Medicine
The Application Of Permanent Middle Cerebral Artery Ligation in the Mouse
1Department of Pharmacology and Physiology, University of Rochester, 2Department of Neurology, University of Alabama at Birmingham, 3Departments of Anesthesiology, Pharmacology and Physiology, University of Rochester
Middle cerebral artery (MCA) ligation is a technique to study focal cerebral ischemia in animal models. In this method, the middle cerebral artery is exposed by craniotomy and ligated by cauterization. This method gives highly reproducible infarct volumes and increased post-operative survival rates compared to other methods available.
JoVE Neuroscience
Assessment of Social Interaction Behaviors
1Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 2Toronto Centre for Phenogenomics, Mount Sinai Hospital, 3Department of Medical Biophysics, University of Toronto, 4Department of Psychology, University of Toronto, 5Department of Psychiatry, University of Toronto
Here we describe a detailed protocol for examination of sociability in mice by using Crawley's sociability and preference for social novelty test. We describe the advantages and possible applications for this procedure, including critical details important for correct interpretation of the results.
JoVE Clinical and Translational Medicine
Fixed Volume or Fixed Pressure: A Murine Model of Hemorrhagic Shock
Department of Surgery, University of Pittsburgh
The Hemorrhagic Shock model has been a reliable and reproducible resource facilitating the identification and understanding of signaling cascades associated with inflammation and end-organ damage after trauma. This article provides a step-by-step description of surgical and mechanical aspects associated with the Hemorrhagic Shock experimental procedure in mice.
JoVE Clinical and Translational Medicine
Acute Myocardial Infarction in Rats
1Department of Internal Medicine, Division of Cardiology, University of Texas Medical Branch, 2Department of Pharmacological and Pharmaceutical Sciences, College of Pharmacy, University of Houston (UH), Texas Medical Center
The rat model of acute myocardial infarction (AMI) is useful to study the consequence of a MI on cardiac pathophysiological and physiological function.
JoVE Immunology and Infection
Comprehensive & Cost Effective Laboratory Monitoring of HIV/AIDS: an African Role Model
1National Health Laboratory Services (NHLS-SA), 2Department of Molecular Medicine and Haematology, University of Witwatersrand, 3Lightcurve Films
Anti-retroviral therapy to treat HIV/AIDS is monitored in South Africa on a large scale. Flow cytometry is combined for haematology (CD45), immunology (CD4) and viral-load linked CD38 assay. Recorded at NHLS-SA laboratories, Johannesburg, these modern methods are cost-efficient with heightened local internal quality control, serving as role-models for resource-limited diagnostics.
JoVE Editorial
December 2011: This Month in JoVE
Here are some highlights from the December 2011 Issue of Journal of Visualized Experiments (JoVE).
JoVE Clinical and Translational Medicine
An Experimental Paradigm for the Prediction of Post-Operative Pain (PPOP)
Department of Anesthesiology and Pain Medicine, University of Washington School of Medicine
Diffuse noxious inhibitory control, temporal summation and wound hyperalgesia testing are demonstrated in the obstetric patient. These tests evaluate inhibitory and excitatory mechanisms of pain processing and are here utilized to evaluate endogenous analgesia at different time-points during pregnancy and the peripartum period to help reveal individual s risk for persistent pain.
JoVE Immunology and Infection
An Allelotyping PCR for Identifying Salmonella enterica serovars Enteritidis, Hadar, Heidelberg, and Typhimurium
Department of Population Health, University of Georgia
We describe a multiplex PCR for the rapid detection of Salmonella enterica serovars Enteritidis, Hadar, Heidelberg, and Typhimurium. Specific Salmonella serovars can be identified by targeting a multiplex PCR to genes and sequences unique to the O-antigen biosynthesis cluster and flagellin of a given serovar. Serovar is assigned then to a Salmonella isolate based on the appearance of specific, size amplicons (PCR product) corresponding to the target allele.
JoVE Applied Physics
Bringing the Visible Universe into Focus with Robo-AO
1Caltech Optical Observatories, California Institute of Technology, 2Department of Astronomy, California Institute of Technology, 3Dunlap Institute for Astronomy and Astrophysics, University of Toronto, 4Inter-University Centre for Astronomy & Astrophysics, 5Observatories of the Carnegie Institution for Science, 6Benoziyo Center for Astrophysics, Weizmann Institute of Science
Light from astronomical objects must travel through the earth's turbulent atmosphere before it can be imaged by ground-based telescopes. To enable direct imaging at maximum theoretical angular resolution, advanced techniques such as those employed by the Robo-AO adaptive-optics system must be used.
JoVE General
Mapping the After-effects of Theta Burst Stimulation on the Human Auditory Cortex with Functional Imaging
Auditory processing is the basis of speech and music-related processing. Transcranial Magnetic Stimulation (TMS) has been used successfully to study cognitive, sensory and motor systems but has rarely been applied to audition. Here we investigated TMS combined with functional Magnetic Resonance Imaging to understand the functional organization of auditory cortex.
JoVE General
Tomato Analyzer: A Useful Software Application to Collect Accurate and Detailed Morphological and Colorimetric Data from Two-dimensional Objects
Department of Horticulture and Crop Science, The Ohio State University
Tomato Analyzer (TA) quantifies attributes of two dimensional shapes and color in a reproducible and accurate manner. A step-by-step procedure for obtaining high quality digitalized images of tomato fruit, morphological and color analyses of these images and several applications using the data generated through this software are described.
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