Methods:
JoVE Immunology and Infection
Diagnosis of Ecto- and Endoparasites in Laboratory Rats and Mice
1Research Animal Diagnostic Services, Charles River, 2Research Models and Services, Charles River, 3Department of Comparative Medicine, University of Washington
This article describes various procedures for screening rats and mice to detect endo- or ectoparasitism. Several diagnostic assays will be demonstrated, both those suitable for use on live animals and those used after euthanasia of the animal. Photographs to aid in identification of rat and mouse parasites will be included.
JoVE Application Notes
Analytical HPLC to Preparative HPLC: Scale Up Techniques using a Natural Product Extract - ADVERTISEMENT
Pharmaceutical Business Operations, Waters Corporation
Using the Waters AutoPurification™ System, separation methods can be developed on an analytical scale and transferred to preparatory scale on the same system.
JoVE Application Notes
The Waters Xevo™ TQ-S Equipped With New StepWave™ and ScanWave™ Technology - ADVERTISEMENT
Pharmaceutical Business Operations, Waters Corporation
JoVE General
Using the GELFREE 8100 Fractionation System for Molecular Weight-Based Fractionation with Liquid Phase Recovery
Research and Development, Protein Discovery, Inc.
The accompanying video describes the use of the GELFREE 8100 Fractionation System, which partitions complex protein samples on the basis of molecular weight and recovers the fractions in liquid phase. The video describes how the technology works, how it is used, and provides resultant data, with polyacrylamide gel electrophoresis analysis of fractionated bovine liver homogenate.
JoVE Editorial
May 2011: This Month in JoVE
The main highlights for our May issue include methods for measuring cognition in zero gravity, isolating mosquito immune cells, engineering recombinant SARS vaccines, and detecting tumors with thermal imaging. In addition, procedures for isolating neural stem cells from human fetal brain and culturing antigen-presenting liver cells will also be released.
JoVE Editorial
April 2011: This Month in JoVE
Here are some highlights from the April 2011 Issue of Journal of Visualized Experiments (JoVE).
JoVE General
Microvolume Protein Concentration Determination using the NanoDrop 2000c Spectrophotometer
Thermo Scientific NanoDrop Products
Microvolume samples are quantified by a spectrophotometer system that uses natural surface tension to retain samples without the use of cuvettes or capillaries. The dynamic range of protein concentrations and speed by which they can be measured are greatly increased with this method.
JoVE Neuroscience
Preparation of Synaptoneurosomes from Mouse Cortex using a Discontinuous Percoll-Sucrose Density Gradient
1Department of Pathology and Laboratory Medicine, Waisman Center for Developmental Disabilities, University of Wisconsin, 2Department of Biochemistry, Waisman Center for Developmental Disabilities, University of Wisconsin
A method to prepare translationally active, intact synaptoneurosomes (SNs) from mouse brain cortex is described. The method uses a discontinuous Percoll-sucrose density gradient allowing for the quick preparation of active SNs.
JoVE General
Microfabricated Post-Array-Detectors (mPADs): an Approach to Isolate Mechanical Forces
1Department of Bioengineering, University of Pennsylvania, 2University of Washington
In this video, we demonstrate how to fabricate and utilize microfabricated post array detectors (mPADs) to assess modulations of cellular contractility.
JoVE Neuroscience
A Novel Method for Assessing Proximal and Distal Forelimb Function in the Rat: the Irvine, Beatties and Bresnahan (IBB) Forelimb Scale
Department of Neurological Surgery, University of California, San Francisco
Here we will describe a rodent behavioral assay that can detect recovery of both proximal and distal forelimb function including digit movements during a naturally occurring behavior that does not require extensive training or deprivation to enhance motivation.
JoVE General
Quantification of dsDNA using the Hitachi F-7000 Fluorescence Spectrophotometer and PicoGreen Dye
Life Sciences Group, Hitachi High Technologies America
Demonstration of quantification of dsDNA using Molecular Probes PicoGreen dye and Hitachi F-7000 Fluorescence Spectrophotometer equipped with a microplate reader accessory.
JoVE General
A Faster, High Resolution, mtPA-GFP-based Mitochondrial Fusion Assay Acquiring Kinetic Data of Multiple Cells in Parallel Using Confocal Microscopy
1Department of Neuroscience, Center for Neuroscience Research, Tufts School of Medicine, 2Department of Internal Medicine, Geriatrics & Gerontology, Wake Forest Baptist Medical Center, 3Department of Medicine, Boston University Medical Center
Mitochondrial fusion was measured by tracking the equilibration of photoconverted matrix-targeted GFP across the mitochondrial network over time. Thus far, only one cell could be subjected to an hour long kinetic analysis at a time. We present a method that simultaneously measures multiple cells, thereby speeding up the data collection process.
JoVE Clinical and Translational Medicine
Experimental Human Pneumococcal Carriage
1Respiratory Infection Group, Liverpool School of Tropical Medicine, 2Royal Liverpool and Broadgreen, University Hospital Trust, 3Comprehensive Local Research Network, 4NIHR Biomedical Research Centre in Microbial Diseases, Royal Liverpool and Broadgreen University Hospitals NHS Trust, 5Institute of Lung Health, Respiratory Biomedical Unit, University Hospitals of Leicester NHS Trust & University of Leicester, 6Department of Clinical Infection Microbiology & Immunology, Institute of Infection & Global Health, University of Liverpool
Experimental human pneumococcal carriage offers a natural model of carriage and a potential model for use in vaccine development. This technique is valuable yet complex and involves clinical risk by introducing a pathogen into a human. We have developed a detailed protocol.
JoVE Editorial
July 2012: This Month in JoVE
1JoVE Content Production, 2Department of Ophthalmology, Massachusetts Eye and Ear
Historically, JoVE, The Journal of Visualized Experiments, has focused primarily on biomedical research and has developed subsections for Bioengineering, Clinical and Translational Medicine, Immunology and Infection, and Neuroscience. This July, JoVE launches its Applied Physics section, which includes a range of content from Plasma Physics to Materials Science. We begin the new section with a notable article from Purdue University, where researchers in the Center for Laser-Based Manufacturing are studying.
JoVE Neuroscience
How to Create and Use Binocular Rivalry
1Department of Psychology, New York University, 2Centre for Neural Science, New York University, 3Department of Psychology, Princeton University, 4Neuroscience Institute, Princeton University
Binocular rivalry occurs when the eyes are presented with different images at the same location: one image dominates while the other is suppressed, and dominance alternates periodically. Rivalry is useful for investigating perceptual selection and visual awareness. Here we describe several easy methods for creating and using binocular rivalry stimuli.
JoVE General
Visualizing RNA Localization in Xenopus Oocytes
Department of Molecular Biology, Cell Biology, and Biochemistry, Brown University
Visualization of in vivo RNA transport is accomplished by microinjection of fluorescently labeled RNA transcripts into Xenopus oocytes, followed by confocal microscopy.
JoVE Neuroscience
Voltage Biasing, Cyclic Voltammetry, & Electrical Impedance Spectroscopy for Neural Interfaces
1Weldon School of Biomedical Engineering, Purdue University, 2Biomedical Engineering, University of Wisconsin-Madison, 3Biomedical Engineering, University of Michigan, 4Department of Biological Sciences, Purdue University
The electrode-tissue interface of neural recording electrodes can be characterized with electrical impedance spectroscopy (EIS) and cyclic voltammetry (CV). Application of voltage biasing changes the electrochemical properties of the electrode-tissue interface and can improve recording capability. Voltage biasing, EIS, CV, and neural recordings are complementary.
JoVE Applied Physics
Characterization of Surface Modifications by White Light Interferometry: Applications in Ion Sputtering, Laser Ablation, and Tribology Experiments
1Materials Science Division, Argonne National Laboratory, 2Energy Systems Division, Argonne National Laboratory, 3MassThink LLC
White light microscope interferometry is an optical, noncontact and quick method for measuring the topography of surfaces. It is shown how the method can be applied toward mechanical wear analysis, where wear scars on tribological test samples are analyzed; and in materials science to determine ion beam sputtering or laser ablation volumes and depths.
JoVE Neuroscience
Recording Behavioral Responses to Reflection in Crayfish
Department of Biological Sciences, Brock University
We have developed two methods for studying effects of visual cues on behavior in the absence of tactile and chemical cues. One method involves videotaping responses of crayfish to reflective walls in an aquarium; the other examines effects of visual inputs provided by a live crayfish behind a transparent partition.
JoVE General
Adult and Embryonic Skeletal Muscle Microexplant Culture and Isolation of Skeletal Muscle Stem Cells
School of Biosciences, University of Birmingham
The micro-dissected explants technique is a robust and reliable method for isolating proliferative skeletal muscle cells from juvenile, adult or embryonic muscles as a source of skeletal muscle stem cells. Uniquely, these cells have been clonally derived to produce skeletal muscle stem cell lines used for in vivo transplantation.
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
Co-analysis of Brain Structure and Function using fMRI and Diffusion-weighted Imaging
1Center for the Neural Basis of Cognition, 2Department of Psychology, University of Pittsburgh, 3Department of Psychology, Carnegie Mellon University, 4Department of Bioengineering, University of Pittsburgh
We describe a novel approach for simultaneous analysis of brain function and structure using magnetic resonance imaging (MRI). We assess brain structure with high-resolution diffusion-weighted imaging and white-matter fiber tractography. Unlike standard structural MRI, these techniques allow us to directly relate anatomical connectivity to functional properties of brain networks.
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 General
Ovariectomy and 17β-estradiol Replacement in Rats and Mice: A Visual Demonstration
Ovariectomy and subsequent replacement of 17β-estradiol by means of silastic capsules and peroral Nutella are demonstrated in rats and mice.
JoVE General
Introducing an Angle Adjustable Cutting Box for Analyzing Slice Shear Force in Meat
1Lacombe Research Centre, Agriculture and Agri-Food Canada, 2Grupo de investigación MERAGEM, Universidad de Córdoba, 3Department of Animal Science, University of Nebraska
Slice shear force is a reference method for beef texture analysis. Using an angle adjustable cutting box could increase its accuracy for research purposes. The results from different locations within the longissimus muscle show a high correlation with Warner-Bratzler shear force methodology and high potential adaptability for different muscles.
JoVE General
High Speed Droplet-based Delivery System for Passive Pumping in Microfluidic Devices
1Materials Science Program, University of Wisconsin-Madison, 2Department of Biomedical Engineering, University of Wisconsin-Madison
A novel microfluidic system has been developed using the phenomenon of passive pumping and a user controlled fluid delivery system. This microfluidic system has the potential to be used in a wide variety of biological applications given its low cost, ease of use, volumetric precision, high speed, repeatability and automation.
JoVE General
Do-It-Yourself Device for Recovery of Cryopreserved Samples Accidentally Dropped into Cryogenic Storage Tanks
1Molecular and Microbiology Department and Center for the Study of Genomics in Liver Diseases, George Mason University, 2Translational Research Institute, Inova Health System, 3Research Center for Medical Genetics RAMS
Here we present a low cost, durable cryotolerant device for sample retrieval from Dewar tanks filled with liquid nitrogen. The ease of construction and modular design of the device makes the process of sample retrieval from cryogenic tanks safe and easy.
JoVE Chemistry
Untargeted Metabolomics from Biological Sources Using Ultraperformance Liquid Chromatography-High Resolution Mass Spectrometry (UPLC-HRMS)
Untargeted metabolomics provides a hypothesis generating snapshot of a metabolic profile. This protocol will demonstrate the extraction and analysis of metabolites from cells, serum, or tissue. A range of metabolites are surveyed using liquid-liquid phase extraction, microflow ultraperformance liquid chromatography/high-resolution mass spectrometry (UPLC-HRMS) coupled to differential analysis software.
JoVE Neuroscience
Creating Objects and Object Categories for Studying Perception and Perceptual Learning
1Brain and Behavior Discovery Institute, Georgia Health Sciences University, 2Vision Discovery Institute, Georgia Health Sciences University, 3Department of Opthalmology, Georgia Health Sciences University, 4Intelligent Systems Laboratory, Palo Alto Research Center, 5Pattern Recognition Systems, Palo Alto Research Center, 6Department of Psychology, University of Minnesota
We describe a novel methodology for creating naturalistic 3-D objects and object categories with precisely defined feature variations. We use simulations of the biological processes of morphogenesis and phylogenesis to create novel, naturalistic virtual 3-D objects and object categories that can then be rendered as visual images or haptic objects.
JoVE Application Notes
LookOut Mycoplasma Elimination Kit - ADVERTISEMENT
Product Management, Sigma-Aldrich
The LookOut Mycoplasma elimination kit combines biological agents that reliably and completely eliminate mycoplasma contamination with minimal cytotoxic effect on cells.
JoVE Editorial
August 2011: This Month in JoVE
Here are some highlights from the August 2011 Issue of Journal of Visualized Experiments (JoVE).
JoVE Editorial
November 2011: This Month in JoVE
Here are some highlights from the November 2011 Issue of Journal of Visualized Experiments (JoVE).
JoVE Editorial
March 2012: This Month in JoVE
Here are some highlights from the March 2012 Issue of Journal of Visualized Experiments (JoVE).
JoVE Editorial
September 2012: This Month in JoVE
1Department of Ophthalmology, Massachusetts Eye and Ear, 2JoVE Content Production
This September in JoVE, researchers from the School of Medicine at the Free University of Berlin demonstrate a novel method for studying how stroke patients compensate for visual field defects. To do this, our authors make use of a driving simulator complete with brakes, a steering wheel, and turn signals. Using driving simulation software and sophisticated eye tracking, researchers can compare the gaze behavior of stroke patients as they navigate through virtual driving courses with varying degrees of complexity. Though posterior cerebral artery infarction can lead to similar visual deficits in patients, some are able to navigate through the driving courses by developing compensatory eye movements, while others crash into dangerous obstacles, like wild boars. Through the analysis of compensatory gaze behavior employed by patients, our authors see great potential for using driving simulation as a tool to rehabilitate stroke patients trying to overcome the blind spots in their visual fields.
JoVE General
Comprehensive Compositional Analysis of Plant Cell Walls (Lignocellulosic biomass) Part I: Lignin
1Great Lakes Bioenergy Research Center, Michigan State University (MSU), 2Great Lakes Bioenergy Research Center and DOE-Plant Research Lab, Michigan State University (MSU)
Plant biomass is a major carbon-neutral renewable resource that could be used for the production of biofuels. Plant biomass consists mainly of cell walls, a structurally complex composite material termed lignocellulosics. Here we describe a protocol for a comprehensive analysis of the content and composition of the polyphenolic lignin.
JoVE Clinical and Translational Medicine
Analytical Techniques for Assaying Nitric Oxide Bioactivity
1Texas Therapeutics Institute, University of Texas Health Science Center at Houston, 2Deptartment of Pediatrics, Baylor College of Medicine
The endogenous production of nitric oxide (NO) regulates a wide variety of biological functions. It is becoming increasingly clear that disruption or dysregulation of NO based signaling is involved in many human diseases. Methods to quantify relevant NO metabolites may provide novel diagnostic or prognostic biomarkers for human disease.
JoVE Neuroscience
Ex vivo Culturing of Whole, Developing Drosophila Brains
1National Institute of Neurological Disorders and Stroke, 2National Human Genome Research Institute, National Institutes of Health, Bethesda, MD
This article describes a method by which one can mimic in vivo development of the Drosophila mushroom body in an ex vivo culture system.
JoVE Neuroscience
Identification of Olfactory Volatiles using Gas Chromatography-Multi-unit Recordings (GCMR) in the Insect Antennal Lobe
Department of Biology, University of Washington
Olfactory cues mediate many different behaviors in insects, and are often complex mixtures comprised of tens to hundreds of volatile compounds. Using gas chromatography with multi-channel recording in the insect antennal lobe, we describe a method for the identification of bioactive compounds.
JoVE Editorial
October 2012: This Month in JoVE
1Department of Ophthalmology, Massachusetts Eye and Ear, 2JoVE Content Production
Here are some highlights from the October 2012 Issue of Journal of Visualized Experiments (JoVE).
JoVE Applied Physics
Atom Probe Tomography Studies on the Cu(In,Ga)Se2 Grain Boundaries
1Department of Microstructure Physics and Alloy Design, Max-Planck-Institut für Eisenforschung GmbH, 2Zentrum für Sonnenenergie- und Wasserstoff-Forschung Baden-Württemberg ( ZSW )
In this work, we describe the use of the atom-probe tomography technique for studying the grain boundaries of the absorber layer in a CIGS solar cell. A novel approach to prepare the atom probe tips containing the desired grain boundary with a known structure is also presented here.
JoVE Clinical and Translational Medicine
Contrast Enhanced Vessel Imaging using MicroCT
1Greehey Children's Cancer Research Institute, University of Texas Health Science Center at San Antonio, 2Small Animal Imaging Resources facility, University of Texas Health Science Center at San Antonio, 3Department of Cellular and Structural Biology, University of Texas Health Science Center at San Antonio, 4Department of Pediatrics, University of Texas Health Science Center at San Antonio
Contrast enhanced small animal vessel imaging by microCT is a rapid, cost-effective and high-throughput technique for serial in situ examination for tumor development, for analyzing the network of blood vessels that nourish them, and for following the response of tumors to preclinical therapeutic intervention(s).
JoVE Editorial
December 2012: This Month in JoVE
1Department of Ophthalmology, Massachusetts Eye and Ear, 2JoVE Content Production
Here are some highlights from the December 2012 Issue of Journal of Visualized Experiments (JoVE).
JoVE General
Automated Hydrophobic Interaction Chromatography Column Selection for Use in Protein Purification
1College of Nursing, Interdisciplinary Life Sciences Research Laboratory, Seattle University, 2College of Science and Engineering, Interdisciplinary Life Sciences Research Laboratory, Seattle University
An automated method for identifying suitable hydrophobic interaction chromatography (HIC) media to be used in the process of protein purification is presented. The method utilizes a medium-pressure liquid chromatography system including automated buffer blending, dynamic sample loop injection, sequential column selection, multi-wavelength analysis, and split fraction eluate collection.
JoVE Bioengineering
A Method for Ovarian Follicle Encapsulation and Culture in a Proteolytically Degradable 3 Dimensional System
1Institute for BioNanotechnology in Advanced Medicine, Northwestern University, 2Department of Obstetrics and Gynecology, Northwestern University, Feinberg School of Medicine, 3Center for Reproductive Research, Northwestern University, 4The Robert H. Lurie Comprehensive Cancer Center, Northwestern University, 5Department of Chemical and Biological Engineering, Northwestern University
A new method for ovarian follicle encapsulation in a 3D fibrin-alginate interpenetrating network is described. This system combines structural support with proteolytic degradation to support the development of immature follicles to produce mature oocytes. This method may be applied to culture cell aggregates to maintain cell-cell contacts without limiting expansion.
JoVE General
A Lectin HPLC Method to Enrich Selectively-glycosylated Peptides from Complex Biological Samples
1Obstetrics, Gynecology and Reproductive Sciences, University of California, San Francisco - UCSF, 2Buck Institute for Age Research, 3Department of Chemistry, Purdue University
Lectin-conjugated POROS beads were employed for HPLC. Glycopeptide standards served as positive and negative controls. MARS-14 depleted, trypsin-digested human plasma was chromatographed and flow-through (FT) and bound fractions collected for ESI-LC-MS/MS analyses. Glycopeptides were enriched in the bound fraction as compared to FT.
JoVE General
Video Bioinformatics Analysis of Human Embryonic Stem Cell Colony Growth
1UCR Stem Cell Center, University of California, 2Department of Cell Biology and Neuroscience, University of California, 3Cell, Molecular, and Developmental Biology Graduate Program, University of California, 4Center for Research in Intelligent Systems, University of California
Video bioinformatics is the automated processing, analysis, understanding, and data mining of biological spatio-temporal data extracted from microscopic videos. The purpose of this article is to demonstrate a method for measuring human embryonic stem cell colony growth using a video bioinformatics method.
JoVE Neuroscience
One Dimensional Turing-Like Handshake Test for Motor Intelligence
Biomedical Engineering, Ben-Gurion University
We present a Turing-like Handshake test administered through a telerobotic system in which the interrogator is holding a robotic stylus and interacting with another party (human or artificial). We use a forced choice method, and extract a measure for the similarity of the artificial model to a human handshake.
JoVE Neuroscience
Physiological, Morphological and Neurochemical Characterization of Neurons Modulated by Movement
Department of Neural and Pain Sciences, University of Maryland
A technique is described to quantify the in vivo physiological response of mammalian neurons during movement and correlate the physiology of the neuron with neuronal morphology, neurochemical phenotype and synaptic microcircuitry.
JoVE Applied Physics
Determining 3D Flow Fields via Multi-camera Light Field Imaging
1Department of Mechanical Engineering, Brigham Young University, 2Naval Undersea Warfare Center, Newport, RI
A technique for performing quantitative three-dimensional (3D) imaging for a range of fluid flows is presented. Using concepts from the area of Light Field Imaging, we reconstruct 3D volumes from arrays of images. Our 3D results span a broad range including velocity fields and multi-phase bubble size distributions.
JoVE Immunology and Infection
A Simple and Efficient Method to Detect Nuclear Factor Activation in Human Neutrophils by Flow Cytometry
1Department of Biological Sciences, University of Alberta, 2División de Estudios de Posgrado e Investigación, Facultad de Odontología, Universidad Nacional Autónoma de México, 3Department of Immunology, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México
Neutrophils are the most abundant leukocytes in blood. Neutrophils possess transcriptionally regulated functions such as production of proinflammatory cytokines and inhibition of apoptosis. These functions can be studied with the method presented here, which allows detection and quantification of nuclear factors by flow cytometry in isolated nuclei
More Results...
