JoVE General
Determining the Contribution of the Energy Systems During Exercise
1Laboratory of Applied Nutrition, School of Physical Education and Sport, University of Sao Paulo, 2Aerobic Performance Research Group, School of Physical Education and Sport, University of Sao Paulo, 3Laboratory of Neuromuscular Adaptations to Strength Training, School of Physical Education and Sport, University of Sao Paulo, 4Martial Arts and Combat Sports Research Group, School of Physical Education and Sport, University of Sao Paulo
This protocol allows researchers focused on exercise and sports sciences to determine the relative contribution of three different energy systems to the total energy expenditure during a large variety of exercises.
JoVE Editorial
March 2012: This Month in JoVE
Here are some highlights from the March 2012 Issue of Journal of Visualized Experiments (JoVE).
JoVE Bioengineering
Continuously-stirred Anaerobic Digester to Convert Organic Wastes into Biogas: System Setup and Basic Operation
Department of Biological and Environmental Engineering, Cornell University
Laboratory-scale anaerobic digesters allow scientists to research new ways of optimizing existing applications of anaerobic biotechnology and to evaluate the methane producing potential of various organic wastes. This article introduces a generalized model for the construction, inoculation, operation, and monitoring of a laboratory-scale continuously stirred anaerobic digester.
JoVE Neuroscience
Hippocampal Insulin Microinjection and In vivo Microdialysis During Spatial Memory Testing
Behavioral Neuroscience, University at Albany
Modulation of hippocampally-dependent spatial working memory by direct intrahippocampal microinjection, accompanied and followed by in vivo microdialysis for metabolites in conscious, behaving animals.
JoVE General
Metabolic Profile Analysis of Zebrafish Embryos
Zebrafish represent a powerful vertebrate model that has been under-utilised for metabolic studies. Here we describe a rapid way to measure the in vivo metabolic profile of developing zebrafish that allows the comparison of different mitochondrial function parameters between genetically or pharmacologically manipulated embryos, thereby increasing the applicability of this organism.
JoVE Clinical and Translational Medicine
Non-invasive Optical Measurement of Cerebral Metabolism and Hemodynamics in Infants
1Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, 2Lab. PALM, Université de Caen Basse-Normandie, 3Fetal-Neonatal Neuroimaging and Developmental Science Center, Boston Children's Hospital, Harvard Medical School, 4ISS, INC.
We combined frequency-domain near-infrared spectroscopy measures of cerebral hemoglobin oxygenation with diffuse correlation spectroscopy measures of cerebral blood flow index to estimate an index of oxygen metabolism. We tested the utility of this measure as a bedside screening tool to evaluate the health and development of the newborn brain.
JoVE General
Extracting DNA from the Gut Microbes of the Termite (Zootermopsis Angusticollis) and Visualizing Gut Microbes
Department of Environmental Science and Engineering, California Institute of Technology - Caltech
This video illustrates the technique for extracting DNA from the species of microbes resident in the termite hindgut. The preparation of a wet mount slide, which is useful for visualizing the gut microbial community is also illustrated, and a tour through the species-rich gut environment is given.
JoVE General
Swimming Performance Assessment in Fishes
Department of Biological Sciences, University of Alberta
The lives of the majority of fish are predicated on swimming. This protocol describes techniques for capturing a range of swimming modes available to individual and schooling fish, and includes metrics associated with swimming physiology and behaviour.
JoVE General
Metabolic Pathway Confirmation and Discovery Through 13C-labeling of Proteinogenic Amino Acids
1Department of Energy, Environmental and Chemical Engineering, Washington University, 2Department of Biology, Washington University, 3Department of Energy, Environmental and Chemical Engineering and Department of Biology, Washington University
13C-isotope labeling is a useful technique for determining the cell central metabolism for various types of microorganisms. After cells have been cultured with a specific labeled substrate, GC-MS measurement can reveal functional metabolic pathways based on unique labeling patterns in proteinogenic amino acids.
JoVE General
Testing Protozoacidal Activity of Ligand-lytic Peptides Against Termite Gut Protozoa in vitro (Protozoa Culture) and in vivo (Microinjection into Termite Hindgut)
Department of Entomology, Louisiana State University Agricultural Center
We present procedures for demonstrating that ligands bind to the surface membrane of the cellulose-digesting protozoa in the gut of Formosan subterranean termites using fluorescent microscopy and that ligands coupled with lytic peptides kill these protozoa in vitro (anaerobic protozoa culture) and in vivo (injection into the termite hindgut).
JoVE General
Design and Use of Multiplexed Chemostat Arrays
Department of Genome Sciences, University of Washington
We developed and validated a small-footprint array of miniature chemostats built from readily available parts for low cost. Physiological and experimental evolution results were similar to larger volume chemostats. The ministat array provides a compact, inexpensive, and accessible platform for traditional chemostat experiments, functional genomics, and chemical screening applications.
JoVE Bioengineering
Monitoring the Reductive and Oxidative Half-Reactions of a Flavin-Dependent Monooxygenase using Stopped-Flow Spectrophotometry
Department of Biochemistry, Virginia Polytechnic Institute and State University
We describe the use of a stopped-flow instrument to investigate both the reductive and oxidative half-reactions of Aspergillus fumigatus siderophore A (SidA), a flavin-dependent monooxygenase. We then show the spectra corresponding to the species in the reaction of SidA and we calculate the rate constants for their formation.
JoVE General
Annotation of Plant Gene Function via Combined Genomics, Metabolomics and Informatics
Molekulare Pflanzenphysiologie, Max-Planck-Institut
Combination of genomics, co-expression gene analysis and the identification of target compounds via metabolism give gene functional annotation.
JoVE Immunology and Infection
Development of a Negative Selectable Marker for Entamoeba histolytica
Division of Infectious Disease and International Health, University of Virginia Health System
We report development of a negative selection system in E. histolytica based upon transgenic expression of a chimeric protein (FCU1) and selection with the prodrug 5-fluorocytosine. The FCU1 protein is a fusion of yeast cytosine deaminase and uracil phosphoribosyltransferase. Expression of FCU1 resulted in increased E. histolytica sensitivity towards 5-fluorocytosine.
JoVE Immunology and Infection
Assessing Hepatic Metabolic Changes During Progressive Colonization of Germ-free Mouse by 1H NMR Spectroscopy
1School of Chemistry, Food and Pharmacy, The University of Reading, 2Department of Nutritional Sciences, The University of Reading
A progressive colonization procedure is described to further assess its impact on the host hepatic metabolism. Colonization is monitored non invasively by evaluating the urinary excretion of microbial co-metabolites by NMR-based metabolic profiling while hepatic metabolism is assessed by High Resolution Magic Angle Spinning (HR MAS) NMR profiling of intact biopsy.
JoVE General
Stable Isotopic Profiling of Intermediary Metabolic Flux in Developing and Adult Stage Caenorhabditis elegans
1Department of Pediatrics, The Children's Hospital of Philadelphia, 2Department of Pediatrics, University of Pennsylvania
Stable isotopic profiling by gas chromatography mass spectrometric analysis of intermediary metabolic flux is described in the nematode, Caenorhabditis elegans. Methods are detailed for assessing isotopic enrichment in carbon dioxide, organic acids, and amino acids following isotope exposure either during development on agar plates or during adulthood in liquid culture.
JoVE Immunology and Infection
Bioluminescent Bacterial Imaging In Vivo
Cork Cancer Research Centre, BioSciences Institute, University College Cork
This article describes the administration of lux-tagged bacteria to mice and subsequent in vivo analysis using IVIS bioluminescence imaging.
JoVE Bioengineering
Cellular Lipid Extraction for Targeted Stable Isotope Dilution Liquid Chromatography-Mass Spectrometry Analysis
1Centers for Cancer Pharmacology and Excellence in Environmental Toxicology, University of Pennsylvania, 2Department of Pharmacology, University of Pennsylvania
This protocol will demonstrate the extraction and analysis of free and esterified bioactive fatty acids from cells. Fatty acids are accurately quantified using stable isotope dilution, chiral liquid chromatography, electron capture atmospheric chemical ionization multiple reaction monitoring mass spectrometry (SID-LC-ECAPCI-MRM/MS).
JoVE Clinical and Translational Medicine
Sampling Human Indigenous Saliva Peptidome Using a Lollipop-Like Ultrafiltration Probe: Simplify and Enhance Peptide Detection for Clinical Mass Spectrometry
1Sanford-Burnham Medical Research Institute, 2Division of Dermatology, University of California, San Diego, 3VA San Diego Healthcare Center, 4Moores Cancer Center, University of California, San Diego
Considering saliva sampling for future clinical application, a lollipop-like ultrafiltration (LLUF) probe was fabricated to fit in the human oral cavity. Direct analysis of undigested saliva by NanoLC-LTQ mass spectrometry demonstrated the ability of LLUF probes to remove large proteins and high abundance proteins, and make low-abundant peptides more detectable.
JoVE Editorial
March 2013: This Month in JoVE
1Department of Ophthalmology, Massachusetts Eye and Ear, 2JoVE Content Production
Here are some highlights from the March 2013 issue of Journal of Visualized Experiments (JoVE).
JoVE Immunology and Infection
Locked Nucleic Acid Flow Cytometry-fluorescence in situ Hybridization (LNA flow-FISH): a Method for Bacterial Small RNA Detection
Center for Bio/Molecular Science and Engineering, Naval Research Laboratory
A novel high-throughput method is described that enables the detection and relative quantitation of small RNA and mRNA expression from single bacterial cells using locked nucleic acid probes and flow cytometry-fluorescence in situ hybridization.
JoVE General
Isolation and Differentiation of Stromal Vascular Cells to Beige/Brite Cells
1UCSF Diabetes Center and Department of Cell and Tissue Biology, University of California, San Francisco, 2Department of Biology, University of Copenhagen, Denmark, 3National Institute of Nutrition and Seafood Research, Bergen, Norway
Primary white preadipocytes isolated from white adipose tissues in mice can be differentiated into beige/brite cells. Presented here is a reliable cellular model system to study the molecular regulation of "browning" of white fat.
JoVE Neuroscience
How to Build a Laser Speckle Contrast Imaging (LSCI) System to Monitor Blood Flow
Biomedical Engineering Department, University of Texas at Austin
This video demonstrates how to build a Laser Speckle Contrast Imaging (LSCI) system that can easily be used to monitor blood flow.
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 General
Biochemical and High Throughput Microscopic Assessment of Fat Mass in Caenorhabditis Elegans
1Center for Human Genetic Research and Department of Medicine, Massachusetts General Hospital and Harvard Medical School, 2Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology
We present robust biochemical and microscopic methods for studying Caenorhabditis elegans lipid stores. A rapid, simple, fixing-staining procedure for fluorescent lipid droplet imaging leverages the spectral properties of the lipophilic dye Nile red. We then present biochemical measurement of triglycerides and phospholipids using solid phase extraction and gas chromatography-mass spectrometry.
JoVE General
Paraffin-Embedded and Frozen Sections of Drosophila Adult Muscles
Gene Expression and Signaling Research Group, Max Planck Institute for Biophysical Chemistry
Identification of mechanisms underlying muscle damage is crucial. Here we present the histological technique for preparing paraffin-embedded and frozen sections of Drosophila thoracic muscles. This allows analysis of muscle morphology and localization of protein and other muscle cell components.
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
Neural Tube Closure in Mouse Whole Embryo Culture
Department of Neurology/Neuroscience, Weill Cornell Medical College
A method allowing for direct pharmacological manipulation of mouse embryos during neurulation that bypasses maternal metabolism is described. The technique can be adapted to study different aspects of neurulation by varying the time point and pharmacological agent.
JoVE Bioengineering
Engineering Adherent Bacteria by Creating a Single Synthetic Curli Operon
1UMR CNRS 5557 Ecologie Microbienne, Université Lyon 1, Université de Lyon, 2Département Biosciences, INSA de Lyon, Université de Lyon, 3INSERM U758, Ecole Normale Supérieure de Lyon, Université de Lyon, 4Laboratoire de Génie Civil et Ingénierie Environnementale, INSA de Lyon, Université de Lyon
The design of a synthetic operon encoding both the secretory apparatus and the structural monomers of curli fibers is described. Overproduction of these amyloids and adherent polymers allows a measurable gain of adherence of the E. coli chassis1. Easy ways to visualize and quantify adherence are explained.
JoVE Chemistry
Large Scale Non-targeted Metabolomic Profiling of Serum by Ultra Performance Liquid Chromatography-Mass Spectrometry (UPLC-MS)
Proteomics and Metabolomics Facility, Colorado State University
Non-targeted metabolite profiling by ultra performance liquid chromatography coupled with mass spectrometry (UPLC-MS) is a powerful technique to investigate metabolism. This article outlines a typical workflow utilized for non-targeted metabolite profiling of serum including sample organization and preparation, data acquisition, data analysis, quality control, and metabolite identification.
JoVE Neuroscience
A Polished and Reinforced Thinned-skull Window for Long-term Imaging of the Mouse Brain
1Department of Physics, University of California, San Diego, 2Department of Engineering Science and Mechanics, Pennsylvania State University, 3Department of Neurosurgery, Pennsylvania State University, 4Section of Neurobiology, University of California, San Diego
We present a method to form an imaging window in the mouse skull that spans millimeters and is stable for months without inflammation of the brain. This method is well suited for longitudinal studies of blood flow, cellular dynamics, and cell/vascular structure using two-photon microscopy.
JoVE General
A 3D System for Culturing Human Articular Chondrocytes in Synovial Fluid
1Department of Anatomy and Cellular Biology, Tufts University School of Medicine, 2Department of Rheumatology, Tufts Medical Center
A 3D system of culturing human articular chondrocytes in high levels of synovial fluid is described. Synovial fluid reflects the most natural microenvironment for articular cartilage, and can be easily obtained and stored. This system thus can be used for studying cartilage regeneration and for screening therapeutics for treating arthritis.
JoVE Immunology and Infection
Sample Preparation of Mycobacterium tuberculosis Extracts for Nuclear Magnetic Resonance Metabolomic Studies
1School of Veterinary Medicine and Biomedical Sciences, University of Nebraska-Lincoln, 2Department of Chemistry, University of Nebraska-Lincoln
The metabolomic profile of Mycobacterium tuberculosis is determined after growth in broth cultures. Conditions can be varied to test the effects of nutritional supplements, oxidants, and anti-tuberculosis agents on the metabolic profile of this microorganism. Procedure for extract preparation is applicable for both 1D 1H and 2D 1H-13C NMR analyses.
JoVE Neuroscience
Simultaneous Electroencephalography, Real-time Measurement of Lactate Concentration and Optogenetic Manipulation of Neuronal Activity in the Rodent Cerebral Cortex
A procedure is described for manipulating the activity of cerebral cortical pyramidal neurons optogenetically while the electroencephalogram, electromyogram, and cerebral lactate concentration are monitored. Experimental recordings are performed on cable-tethered mice while they undergo spontaneous sleep/wake cycles. Optogenetic equipment is assembled in our laboratory; recording equipment is commercially available.
JoVE General
One-step Metabolomics: Carbohydrates, Organic and Amino Acids Quantified in a Single Procedure
The urease method of sample preparation for GC/MS analysis of intermediary metabolites is presented by its inventor. The method allows one-step follow-up of newborn screening for inborn errors by tandem mass spectrometry by quantifying carbohydrates, organic and amino acids all in a single process.
JoVE Immunology and Infection
Isolation of Adipose Tissue Immune Cells
Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine
Adipose tissue (AT) is a site of intense immune cell activation and interaction. Almost all cells of the immune system are present in AT and their ratios are altered by obesity. Proper isolation, quantification, and characterization of AT immune cell populations are critical for understanding their role in immunometabolic disease.
JoVE Immunology and Infection
Use of Artificial Sputum Medium to Test Antibiotic Efficacy Against Pseudomonas aeruginosa in Conditions More Relevant to the Cystic Fibrosis Lung
1Institute of Infection and Global Health, University of Liverpool, 2NIHR Biomedical Research Centre in Microbial Disease, University of Liverpool
Current diagnostic antimicrobial susceptibility testing relies on the planktonic growth of isolates in nutrient rich, aerobic conditions. Here, we employ an alternative artificial sputum medium to study antimicrobial susceptibility of Pseudomonas aeruginosa biofilms under both aerobic and microaerophilic conditions more representative of the cystic fibrosis lung.
JoVE Bioengineering
Three-dimensional Optical-resolution Photoacoustic Microscopy
Optical Imaging Laboratory, Department of Biomedical Engineering, Washington University in St. Louis
Optical-resolution photoacoustic microscopy (OR-PAM) is an emerging technology capable of imaging optical absorption contrasts in vivo with cellular resolution and sensitivity. Here, we provide a visualized instruction on the experimental protocols of OR-PAM, including system configuration, system alignment, typical in vivo experimental procedures, and functional imaging schemes.
JoVE Bioengineering
A Microfluidic Device for Studying Multiple Distinct Strains
We present a simple method to produce microfluidic devices capable of applying similar dynamic conditions to multiple distinct strains, without the need for a clean room or soft lithography.
JoVE General
Preparation of Highly Coupled Rat Heart Mitochondria
1Faculty of Life Sciences, University of Manchester, 2School of Biological Sciences, Queen's University Belfast
We describe а protocol for isolation of pure, highly coupled rat heart mitochondria for functional or structural studies of cellular bioenergetics, biophysical measurements, proteomics or mitochondrial DNA and lipids analysis.
JoVE General
Large Scale Zebrafish-Based In vivo Small Molecule Screen
1Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University School of Medicine, 2Department of Pharmacology, Vanderbilt University School of Medicine, 3Vanderbilt Institute of Chemical Biology, Vanderbilt University School of Medicine, 4Research Medicine, Veterans Affairs TVHS, Vanderbilt University School of Medicine
Zebrafish has emerged as a powerful in vivo platform for phenotype-based drug screens and chemical genetic analysis. Here, we demonstrate a simple, practical method for large-scale screening of small molecules using zebrafish embryos.
JoVE Clinical and Translational Medicine
Dual-mode Imaging of Cutaneous Tissue Oxygenation and Vascular Function
1Department of Biomedical Engineering, The Ohio State University, 2Department of Biomedical Informatics, The Ohio State University, 3Comprehensive Wound Center, The Ohio State University, 4Department of Surgery, The Ohio State University
A dual-mode imaging system was developed for non-contact assessment of cutaneous tissue oxygenation and vascular function.
JoVE General
Proteomics to Identify Proteins Interacting with P2X2 Ligand-Gated Cation Channels
1Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles, 2Department of Anesthesiology, David Geffen School of Medicine, University of California, Los Angeles, 3Department of Anesthesiology, Medicine and Physiology, David Geffen School of Medicine, University of California, Los Angeles
We describe a simple protocol to identify brain proteins that bind to the full length C terminus of ATP-gated P2X2 receptors. The extension and systematic application of this approach to all P2X receptors is expected to lead to a better understanding of P2X receptor signaling.
JoVE General
Bioenergetic Profile Experiment using C2C12 Myoblast Cells
1Buck Institute for Age Research, Novato, CA, 2Department of Pathology, Center for Free Radical Biology, University of Alabama at Birmingham - UAB, 3Seahorse Bioscience, North Billerica, MA
A description of a method for profiling mitochondrial function in cells is provided. The mitochondrial profile generated provides four parameters of mitochondrial function that can be measured in one experiment: basal respiration rate, ATP-linked respiration, proton leak, and reserve capacity.
JoVE Neuroscience
Autologous Blood Injection to Model Spontaneous Intracerebral Hemorrhage in Mice
1Department of Neurology, University of Connecticut Health Center, 2Department of Neurology, School of Medicine, University of Pennsylvania, 3Department of Neurosurgery, Hartford Hospital, 4Department of Neurosurgery, School of Medicine, University of Pennsylvania
The autologous blood injection model of intracerebral hemorrhage in mice described in this protocol uses the double injection technique to minimize risk of blood reflux up the needle track, no anticoagulants in the pumping system, and eliminates all dead space and expandable tubing in the system.
JoVE General
Detection of Signaling Effector-Complexes Downstream of BMP4 Using in situ PLA, a Proximity Ligation Assay
Medical Research Council, Clinical Sciences Centre, Imperial College, Hammersmith Hospital
Here we show how to use Proximity Ligation Assay (PLA), with a combination of antibodies to visualize Bone Morphogenetic Protein (BMP) signaling in fixed cells. This technique allowed us to follow the nuclear accumulation of endogenous BMP activated effector-complexes and quantify their levels over time under BMP4 stimulation.
JoVE Neuroscience
Organotypic Culture of Full-thickness Adult Porcine Retina
1Neurology and Neurosciences, University of Medicine and Dentistry of New Jersey - UMDNJ, 2Institute of Ophthalmology and Visual Science, University of Medicine and Dentistry of New Jersey - UMDNJ
Here we describe a cost-effective technique for organotypic culture of adult porcine retina for seven days. Briefly, a sterile filter paper was used to lift the neural retina off from the RPE and place photoreceptor side up on an insert raised by a custom-made stand.
JoVE General
Using SCOPE to Identify Potential Regulatory Motifs in Coregulated Genes
Department of Biology, Dartmouth College
A straight-forward and robust method to identify potential regulatory motifs in co-regulated genes is presented. SCOPE does not require any user parameters and returns motifs that represent excellent candidates for regulatory signals. The identification of such regulatory signals helps to understand the underlying biology.
JoVE General
Insulin Injection and Hemolymph Extraction to Measure Insulin Sensitivity in Adult Drosophila melanogaster
1Department of Biology, State University of New York, 2Allied Health Sciences, University of Connecticut
Conserved insulin signaling pathways found in the fruit fly Drosophila melanogaster make this organism a potential tool for modeling metabolic disorders including type II diabetes. To this end, it is critical to establish physiological assays to effectively measure systemic insulin action in peripheral glucose disposal in the adult fly.
JoVE Clinical and Translational Medicine
Segmentation and Measurement of Fat Volumes in Murine Obesity Models Using X-ray Computed Tomography
1Carestream Molecular Imaging, 2Department of Chemistry and Biochemistry, University of Notre Dame, 3Freimann Life Science Center, University of Notre Dame, 4Research and Development, Oncovision, GEM-Imaging S.A.
Fat content analysis is routinely conducted in studies utilizing murine obesity models. Emerging methods in small animal CT imaging and analysis are providing for longitudinal detail rich fat content analysis. Here we detail step by step procedures for performing small animal CT imaging, analysis, and visualization.
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