JoVE General
Phase Contrast and Differential Interference Contrast (DIC) Microscopy
Core Optical Imaging Facility, University of Texas Health Science Center at San Antonio (UTHSCSA)
This protocol highlights the principles and practical applications of Phase and Differential Interference Contrast (DIC) Microscopy
JoVE Neuroscience
Investigating the Neural Mechanisms of Aware and Unaware Fear Memory with fMRI
Department of Psychology, University of Alabama at Birmingham
A methodology to investigate the neural mechanisms that support aware and unaware memory processes during fear conditioning is described. This method monitors blood oxygen level dependent (BOLD) functional magnetic resonance imaging, skin conductance response, and unconditioned stimulus expectancy during Pavlovian fear conditioning to assess the neural correlates of distinct memory processes.
JoVE Neuroscience
Recording Human Electrocorticographic (ECoG) Signals for Neuroscientific Research and Real-time Functional Cortical Mapping
1Wadsworth Center, New York State Department of Health, 2Department of Neurology, Albany Medical College, 3Department of Neurosurgery, Albany Medical College, 4Department of Neurosurgery, Washington University, 5Department of Biomed. Eng., Rensselaer Polytechnic Institute, 6Department of Biomed. Sci., State University of New York at Albany, 7Department of Elec. and Comp. Eng., University of Texas at El Paso
We present a method for collecting electrocorticographic signals for research purposes from humans who are undergoing invasive epilepsy monitoring. We show how to use the BCI2000 software platform for data collection, signal processing and stimulus presentation. Specifically, we demonstrate SIGFRIED, a BCI2000-based tool for real-time functional brain mapping.
JoVE Immunology and Infection
Isolation of Human Umbilical Vein Endothelial Cells and Their Use in the Study of Neutrophil Transmigration Under Flow Conditions
Department of Physiology and Pharmacology, University of Calgary
This article first describes a procedure for isolating human endothelial cells from umbilical veins and then shows how to use these cells to examine neutrophil transmigration under flow conditions. By using a low-volume flow chamber made from a polymer with the optical characteristics of glass, live-cell fluorescent imaging of rare cell populations is also possible.
JoVE General
Imaging C. elegans Embryos using an Epifluorescent Microscope and Open Source Software
Human Genetics, University of Michigan
The C. elegans embryo is a powerful system for studying cell biology and development. We present a protocol for live imaging of C. elegans embryos utilizing DIC optics or fluorescence using readily available epifluorescent microscopes and open-source software.
JoVE General
Basic Caenorhabditis elegans Methods: Synchronization and Observation
1Department of Cancer and Human Molecular Genetics, Bellvitge Institute for Biomedical Research, 2C. elegans Core Facility, Bellvitge Institute for Biomedical Research
The easiness of maintaining and propagating the nematode C. elegans make it a nice model organism to work with. The possibility of synchronizing worms allows the work with a significant amount of subjects at the same developmental stage, what facilitates the study of one particular process in many animals.
JoVE Clinical and Translational Medicine
In vivo Measurement of the Mouse Pulmonary Endothelial Surface Layer
Division of Pulmonary Sciences and Critical Care Medicine, University of Colorado School of Medicine
The endothelial glycocalyx/endothelial surface layer is ideally studied using intravital microscopy. Intravital microscopy is technically challenging in a moving organ such as the lung. We demonstrate how simultaneous brightfield and fluorescent microscopy may be used to estimate endothelial surface layer thickness in a freely-moving in vivo mouse lung.
JoVE Neuroscience
Imaging Odor-Evoked Activities in the Mouse Olfactory Bulb using Optical Reflectance and Autofluorescence Signals
This article presents the protocols of intrinsic optical signals and flavoproteins autofluorescence signals imaging to map odor-evoked activities at the surface of the olfactory bulb in mice.
JoVE General
Whole Mount in Situ Hybridization of E8.5 to E11.5 Mouse Embryos
Department of Genetics, University of Georgia
This whole mount in situ hybridization protocol discusses critical steps that ensure reproducible high quality results for gene expression studies in E8.5-E11.5 day old mouse embryos.
JoVE General
Assembly, Tuning and Use of an Apertureless Near Field Infrared Microscope for Protein Imaging
1Department of Chemistry, University of Toronto, 2Department of Chemistry, University of Wisconsin, 3Department of Chemistry, Duke University
The assembly of a nearfield infrared microscope for imaging protein aggregates is described.
JoVE Neuroscience
High Density Event-related Potential Data Acquisition in Cognitive Neuroscience
Department of Psychology, Boston College
Event-related potential (ERP) recording is under utilized in Cognitive Neuroscience because data acquisition techniques are not readily available and this method often has poor spatial resolution. To foster the increased use of ERPs in Cognitive Neuroscience, the present article details key techniques involved in high density ERP data acquisition.
JoVE Immunology and Infection
Co-culture Models of Pseudomonas aeruginosa Biofilms Grown on Live Human Airway Cells
1Department of Physiology, Dartmouth College, 2Department of Biology, Indiana University Purdue University Indianapolis
This paper describes different methods of growing Pseudomonas aeruginosa biofilms on cultured human airway epithelial cells. These protocols can be adapted to study different aspects of biofilm formation, including visualization of the biofilm, staining of the biofilm, measuring the colony forming units (CFU) of the biofilm, and studying biofilm cytotoxicity.
JoVE Applied Physics
Nanomoulding of Functional Materials, a Versatile Complementary Pattern Replication Method to Nanoimprinting
1Institute of Microengineering (IMT), Photovoltaics and Thin Film Electronics Laboratory, Ecole Polytechnique Fédérale de Lausanne (EPFL), 2Department of Electrical Engineering and Computer Sciences, University of California, Berkeley
We describe a nanomoulding technique which allows low-cost nanoscale patterning of functional materials, materials stacks and full devices. Nanomoulding can be performed on any nanoimprinting setup and can be applied to a wide range of materials and deposition processes.
JoVE General
Preparation, Purification, and Characterization of Lanthanide Complexes for Use as Contrast Agents for Magnetic Resonance Imaging
Department of Chemistry, Wayne State University
We demonstrate the metalation, purification, and characterization of lanthanide complexes. The complexes described here can be conjugated to macromolecules to enable tracking of these molecules using magnetic resonance imaging.
JoVE General
Born Normalization for Fluorescence Optical Projection Tomography for Whole Heart Imaging
1Center for Systems Biology, Harvard Medical School, 2Center for Systems Biology, MGH - Massachusetts General Hospital, 3Institute for Biological and Medical Imaging, Technical University of Munich and Helmholtz Center Munich
We suggest a Born normalized approach for Optical Projection Tomography (BnOPT) that accounts for the absorption properties of imaged samples to obtain accurate and quantitative fluorescence tomographic reconstructions. We use the proposed algorithm to reconstruct the fluorescence molecular probe distribution within small animal organs.
JoVE Clinical and Translational Medicine
Multispectral Real-time Fluorescence Imaging for Intraoperative Detection of the Sentinel Lymph Node in Gynecologic Oncology
1Department of Surgery, Division of Surgical Oncology, University Medical Center Groningen, 2Helmholtz Zentrum, Technical University Munich, 3Department of Obstetrics and Gynaecology, University Medical Center Groningen
Fluorescence imaging is a promising innovative modality for image-guided surgery in surgical oncology. In this video we describe the technical procedure for detection of the sentinel lymph node using fluorescence imaging as showcased in gynecologic oncologicy. A multispectral fluorescence camera system, together with the fluorescent agent indocyanine green, is applied.
JoVE Clinical and Translational Medicine
The Use of Thermal Infra-Red Imaging to Detect Delayed Onset Muscle Soreness
1Loma Linda University, 2Azusa Pacific University
The purpose of this investigation was to assess whether using an infra-red thermal camera is a valid tool for detecting and quantifying the muscle soreness after exercising.
JoVE Immunology and Infection
Measurement of Factor V Activity in Human Plasma Using a Microplate Coagulation Assay
1Applied Bioscience Program, Faculty of Science, University of Ontario Institute of Technology, 2Nursing Program, Faculty of Health Sciences, University of Ontario Institute of Technology, 3Medical Laboratory Science Program, Faculty of Health Sciences, University of Ontario Institute of Technology
This study describes a novel microplate assay that measures FV coagulation activity during fibrin clot formation in human plasma which has not been reported previously. The method uses a kinetic microplate reader to continuously measure the change in absorbance at 405nm during fibrin clot formation in human plasma.
JoVE Clinical and Translational Medicine
An in vivo Assay to Test Blood Vessel Permeability
We are presenting an in vivo assay to test blood vessel permeability. This assay is based on intravenous injection of a dye and subsequent visualization of its diffusion into interstitial spaces.
JoVE Clinical and Translational Medicine
Multifocal Electroretinograms
John A. Moran Eye Center, University of Utah
The development of the multifocal electroretinogram (mfERG) is an important advance in the diagnosis and characterization of retinopathy. Multifocal electroretinograms are a mathematical average of an approximation of a b-wave. Software programs can derive ERGs from more than a hundred retinal areas in a few minutes per eye. Scotomas and retinal dysfunction can be mapped and quantified.
JoVE Bioengineering
Visualization of Cortex Organization and Dynamics in Microorganisms, using Total Internal Reflection Fluorescence Microscopy
1AG Cellular Dynamics and Cell Patterning, Max Planck Institute of Biochemistry, 2Helmholtz Zentrum München
Total Internal Reflection Fluorescence (TIRF) microscopy is a powerful approach to observe structures close to the cell surface at high contrast and temporal resolution. We demonstrate how TIRF can be employed to study protein dynamics at the cortex of cell wall-enclosed bacterial and fungal cells.
JoVE General
Fluorescence Activated Cell Sorting of Plant Protoplasts
Center for Genomics and Systems Biology, Department of Biology, New York University
A method for isolating specific cell types from plant material is demonstrated. This technique employs transgenic marker lines expressing fluorescent proteins in particular cell types, cellular dissociation and Fluorescence Activated Cell Sorting. Additionally, a growth setup is established here that facilitates treatment of Arabidopsis thaliana seedlings prior to cell sorting.
JoVE General
Single-molecule Imaging of Gene Regulation In vivo Using Cotranslational Activation by Cleavage (CoTrAC)
1Department of Biophysics and Biophysical Chemistry, Johns Hopkins University School of Medicine, 2Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 3Department of Physics, Jilin University
We describe a fluorescence microscopy method, Co-Translational Activation by Cleavage (CoTrAC), to image the production of protein molecules in live cells with single-molecule precision without perturbing the protein's functionality. This method has been used to follow the stochastic expression dynamics of a transcription factor, the λ repressor CI 1.
JoVE General
Visually Mediated Odor Tracking During Flight in Drosophila
Department of Physiological Science, University of California, Los Angeles
Here we describe how to optimize the acquired video image for an olfactory magnetic-tether (OMT) apparatus. We also describe two sample experimental protocols for studying visuo-olfactory fusion.
JoVE Neuroscience
Behavioral Determination of Stimulus Pair Discrimination of Auditory Acoustic and Electrical Stimuli Using a Classical Conditioning and Heart-rate Approach
School of Psychological Science, La Trobe University
The application of a classical fear conditioning behavioral paradigm for auditory prosthetic research in rats is described. This paradigm provides a mechanism for identifying both detection of, and discrimination between, distinct acoustic and electrical stimuli using heart-rate as an outcome measure.
JoVE Neuroscience
Physiological Recordings of High and Low Output NMJs on the Crayfish Leg Extensor Muscle
Department of Biology, University of Kentucky
This article demonstrates how to conduct electrophysiological recordings of synaptic responses on the extensor muscle in the walking leg of a crayfish and how the nerve terminals are visualized to show the gross morphological differences of high- and low-output nerve terminals.
JoVE Clinical and Translational Medicine
Time-lapse Imaging of Primary Preneoplastic Mammary Epithelial Cells Derived from Genetically Engineered Mouse Models of Breast Cancer
1Department of Oncology, Georgetown University, 2Lombardi Comprehensive Cancer Center, Georgetown University, 3Stem Cell Dynamics, Helmholtz Zentrum München - German Research Center for Environmental Health, 4Department of Medicine, Georgetown University, 5Department of Nanobiomedical Science and WCU Research Center of Nanobiomedical Science, Dankook University
Time-lapse imaging is used to assess behavior of primary preneoplastic mammary epithelial cells derived from genetically engineered mouse models of breast cancer risk to determine if there are correlations between specific behavioral parameters and distinct genetic lesions.
JoVE Applied Physics
Fabrication And Characterization Of Photonic Crystal Slow Light Waveguides And Cavities
School of Physics & Astronomy, University of St Andrews
Use of photonic crystal slow light waveguides and cavities has been widely adopted by the photonics community in many differing applications. Therefore fabrication and characterization of these devices are of great interest. This paper outlines our fabrication technique and two optical characterization methods, namely: interferometric (waveguides) and resonant scattering (cavities).
JoVE Bioengineering
Mass Cytometry: Protocol for Daily Tuning and Running Cell Samples on a CyTOF Mass Cytometer
The steps necessary for daily tuning and optimization of the performance of a CyTOF mass cytometer are described. Comments on optimal sample preparation and flow rate are discussed
JoVE Clinical and Translational Medicine
Roux-en-Y Gastric Bypass Operation in Rats
1Department of Surgery, University Hospital Zürich, 2Zürich Centre for Integrative Human Physiology, University of Zürich, 3Institute of Veterinary Physiology, Vetsuisse Faculty, University of Zürich, 4Imperial Weight Centre, Department of Investigative Medicine, Imperial College London
Numerous studies using gastric bypass rat models have been recently conducted to uncover the underlying physiological mechanisms of Roux-en-Y gastric bypass operations. This article aims to demonstrate and discuss the technical and experimental details of our published gastric bypass rat model to understand advantages and limitations of this experimental tool.
JoVE Neuroscience
Brain Imaging Investigation of the Impairing Effect of Emotion on Cognition
1Department of Psychiatry, University of Alberta, 2Centre for Neuroscience, University of Alberta, 3Department of Psychology, University of Illinois, 4Brain Imaging and Analysis Center, Duke University, 5Department of Psychiatry and Behavioral Sciences, Duke University, 6Mid-Atlantic Mental Illness Research Education and Clinical Center, VA Medical Center, 7Department of Psychology, Yale University, 8Neuroscience Program, University of Illinois, 9Beckman Institute for Advanced Science & Technology, University of Illinois
We present a protocol that allows investigation of the neural mechanisms mediating the detrimental impact of emotion on cognition, using functional magnetic resonance imaging. This protocol can be used with both healthy and clinical participants.
JoVE General
Bacterial Delivery of RNAi Effectors: Transkingdom RNAi
Institute of Pathology, Charité Campus Mitte
For development of RNA interference (RNAi)-based therapies, a novel strategy was developed, transkingdom RNAi (tkRNAi). This technology uses non-pathogenic bacteria to produce and deliver therapeutic short hairpin RNA (shRNA) into target cells. Here, tkRNAi was successfully applied for reversal of classical ABCB1-mediated multidrug resistance (MDR) of cancer cells.
JoVE General
Gastrointestinal Motility Monitor (GIMM)
Department of Anatomy and Neurobiology, The University of Vermont
Evaluation of colonic motility in the guinea pig distal colon with the Gastrointestinal Motility Monitor (GIMM) is a straightforward and simple to learn approach to quantitatively evaluate propulsive motility in the gastrointestinal tract.
JoVE Neuroscience
Using MazeSuite and Functional Near Infrared Spectroscopy to Study Learning in Spatial Navigation
1School of Biomedical Engineering, Science and Health Systems, Drexel University, 2College of Nursing and Health Professions, Drexel University
MazeSuite is a complete toolset to prepare, present and analyze navigational and spatial experiments. Functional near-infrared spectroscopy (fNIR) is an optical brain imaging technique that enables noninvasive and portable monitoring of cerebral blood oxygenation changes. This paper summarizes collective use of MazeSuite and fNIR within a cognitive processing learning paradigm.
JoVE Bioengineering
In vitro Synthesis of Native, Fibrous Long Spacing and Segmental Long Spacing Collagen
1Department of Chemistry, University of Toronto, 2Institute for Optical Sciences, University of Toronto
Simple and reproducible procedures are described for making three structurally distinct collagen assemblies from a common commercially available Type I collagen monomer. Native type, fibrous long spacing or segmental long spacing collagen can be constructed by varying the conditions to which the 300 nm long and 1.4 nm diameter monomer building block is exposed.
JoVE Neuroscience
Basics of Multivariate Analysis in Neuroimaging Data
Department of Neurology, Columbia University
The current article describes the basics of multivariate analysis and contrasts it to the more commonly used voxel-wise univariate analysis. Both types of analysis are applied to a clinical-neuroscience data set. Supplementary split-half simulations show better replication of the multivariate results in independent data sets.
JoVE Immunology and Infection
RNA Interference in Ticks
1Department of Veterinary Pathobiology, Center for Veterinary Health Sciences, Oklahoma State University, 2(CSIC-UCLM-JCCM), Instituto de Investigación en Recursos Cinegéticos IREC
A method for RNA interference (RNAi) by injection of dsRNA into unfed ticks is described. RNAi is the most widely used gene-silencing technique in ticks where the use of other methods of genetic manipulation has been limited.
JoVE Bioengineering
Separating Beads and Cells in Multi-channel Microfluidic Devices Using Dielectrophoresis and Laminar Flow
1Electrical and Computer Engineering, University of Illinois at Urbana-Champaign, 2Micro and Nanotechnology Lab, University of Illinois at Urbana-Champaign, 3Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, 4Bioengineering, University of Illinois at Urbana-Champaign
Dielectrophoresis (DEP) is an effective method to manipulate cells. Printed circuit boards (PCB) can provide inexpensive, reusable and effective electrodes for contact-free cell manipulation within microfluidic devices. By combining PDMS-based microfluidic channels with coverslips on PCBs, we demonstrate bead and cell manipulation and separation within multichannel microfluidic devices.
JoVE Clinical and Translational Medicine
Direct Pressure Monitoring Accurately Predicts Pulmonary Vein Occlusion During Cryoballoon Ablation
1Department of Cardiac Electrophysiology, Piedmont Heart Institute, 2Cardiac Rhythm, Medtronic Inc.
Effective pulmonary vein isolation utilizing a cryoballoon depends on complete pulmonary vein occlusion. The point of occlusion can be effectively predicted by direct analysis of pulmonary vein pressure waveform analysis during balloon inflation using a simple and reproducible technique.
JoVE Clinical and Translational Medicine
How to Measure Cortical Folding from MR Images: a Step-by-Step Tutorial to Compute Local Gyrification Index
1Department of Psychiatry, University of Geneva School of Medicine, 2Signal Processing Laboratory, École Polytechnique Fédérale de Lausanne, 3Department of Radiology, University Hospital Center and University of Lausanne, 4Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital
Measuring gyrification (cortical folding) at any age represents a window into early brain development. Hence, we previously developed an algorithm to measure local gyrification at thousands of points over the hemisphere1. In this paper, we detail the computation of this local gyrification index.
JoVE Behavior
Perceptual and Category Processing of the Uncanny Valley Hypothesis' Dimension of Human Likeness: Some Methodological Issues
Department of Neuropsychology, University of Zurich
Investigation of the Uncanny Valley Hypothesis and affective experience requires an understanding of the hypothesis' dimension of human likeness (DHL). This protocol allows representation of the DHL and examination of categorical perception. Use of the same stimuli and fMRI to distinguish brain regions responsive to physical and category change is illustrated.
JoVE Neuroscience
Intravascular Perfusion of Carbon Black Ink Allows Reliable Visualization of Cerebral Vessels
Department of Neurology, University of Duisburg-Essen Medical School
Analysis of rodent cerebrovascular anatomy plays an important role in experimental stroke research. In this context, intravascular perfusion with colored latex has been considered as a standard tool for several years. However, this technique implies distinct technical limitations, which undermine its reproducibility. Here, we describe a simple method to visualize cerebral vessels in a reproducible manner. Injection of a mixture of two commercially available carbon black inks through the left myocardial ventricle results in adequate filling of cerebral vessels with high contrast visualization. We have successfully applied this technique to identify anastomotic points between cerebral vascular territories of mice with different genetic backgrounds. We finally give evidence that this novel and simple method for vessel staining can be combined with triphenyltetrazolium chloride (TTC) staining - a widely used tool to observe and analyze infarct volumes in mice.
JoVE Immunology and Infection
Protein Misfolding Cyclic Amplification of Prions
1Department of Civil Engineering, University of Nebraska at Lincoln, 2Department of Medical Microbiology and Immunology, Creighton University
Protein misfolding cyclic amplification (PMCA) is an in vitro assay for the study of prion conversion and strain and species barriers. It can also be used as a prion detection assay.
JoVE General
BioMEMS: Forging New Collaborations Between Biologists and Engineers
Department of Biomedical Engineering, University of California, Irvine (UCI)
JoVE General
The Microfluidic Probe: Operation and Use for Localized Surface Processing
Department of Biomedical Engineering, McGill University
In this video we present the microfluidic probe1 (MFP). We explain in detail how to assemble the MFP, mount it atop an inverted microscope, and align it relative to the substrate surface, and finally show how to use it to process a substrate surface immersed in a buffer solution.
JoVE Neuroscience
Spinal Cord Electrophysiology II: Extracellular Suction Electrode Fabrication
A demonstration of the fabrication and use of an extracellular suction electrode used to measure electrophysiological recordings of neonatal rodent spinal cords in vitro
JoVE Neuroscience
VisioTracker, an Innovative Automated Approach to Oculomotor Analysis
1Institute of Molecular Life Sciences, University of Zurich, 2TSE Systems GmbH
The VisioTracker is an automated system for the quantitative analysis of visual performance of larval and small adult fish based on the recording of eye movements. It features full control over visual stimulus properties and real-time analysis, enabling high-throughput research in fields such as visual system development and function, pharmacology, neural circuit studies and sensorimotor integration.
JoVE General
Live Imaging of Glial Cell Migration in the Drosophila Eye Imaginal Disc
Department of Zoology, University of British Columbia - UBC
Here we describe a protocol to examine the migration of glial cells into the developing Drosophila eye using live microscopic analysis paired with GFP tagged glial cells.
JoVE General
Photoconversion of Purified Fluorescent Proteins and Dual-probe Optical Highlighting in Live Cells
Department of Molecular Physiology and Biophysics, Vanderbilt University
This protocol describes a general approach to perform photoconversion of fluorescent proteins on a confocal laser scanning microscope. We describe procedures for the photoconversion of puried protein samples, as well as for dual-probe optical highlighting in live cells with mOrange2 and Dronpa.
JoVE Immunology and Infection
Toxoplasma gondii Cyst Wall Formation in Activated Bone Marrow-derived Macrophages and Bradyzoite Conditions
Department of Medical Microbiology and Immunology, University of Wisconsin
Toxoplasma gondii converts to a cyst form in response to environmental stresses, which can be mimicked in tissue culture models. This video demonstrates techniques to examine cyst wall formation by activating bone marrow-derived macrophages or changing growth medium pH in fibroblast cells.
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