JoVE General
Pharmacological and Functional Genetic Assays to Manipulate Regeneration of the Planarian Dugesia japonica
Department of Pharmacology and The Stem Cell Institute, University of Minnesota Medical School
An attractive model for studying stem cell differentiation within a live animal is the planarian flatworm. Regeneration is studied by simple amputation experiments that are easily performed in a basic laboratory and are amenable to pharmacological and genetic (in vivo RNAi) manipulation as detailed by protocols in this article.
JoVE General
Protocol for Mosquito Rearing (A. gambiae)
Malaria Research Institute, Bloomberg School of Public Health, Johns Hopkins University
This video illustrates the general techniques used to rear Anopheles gambiae in the laboratory. The methods for caring for laboratory mosquitoes are demonstrated through all stages of the organism's life cycle from larvae to pupae to blood-feeding adults.
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 General
Protocol for Plasmodium falciparum Infections in Mosquitoes and Infection Phenotype Determination
Malaria Research Institute, Bloomberg School of Public Health, Johns Hopkins University
Once a gene is identified as potentially refractory for malaria, it must be evaluated for its role in preventing Plasmodium infections within the mosquito. This protocol illustrates how the extent of plasmodium infections of mosquitoes can be assayed. The techniques for preparing the gametocyte culture, membrane feeding mosquitoes human blood, and assaying viral titers in the mosquito midgut are demonstrated.
JoVE Neuroscience
Behavioural Pharmacology in Classical Conditioning of the Proboscis Extension Response in Honeybees (Apis mellifera)
Fachbereich Bio/Chem/Pharm, Institut für Biologie – Neurobiologie, Freie Universität Berlin
We demonstrate how to implement a behavioral pharmacology method in an appetitive olfactory conditioning paradigm in honeybees (Apis mellifera) by systemic application of drugs. This method allows investigation of the mechanisms underlying learning and memory formation in a simple and reliable way.
JoVE Bioengineering
Engineering Biological-Based Vascular Grafts Using a Pulsatile Bioreactor
1Department of Biomedical Engineering, Yale University, 2Department of Anesthesiology, Yale University School of Medicine
Our group has developed a bioreactor culture system that mimics the physiological pulsatile stresses of the cardiovascular system to regenerate implantable small-diameter vascular grafts.
JoVE Applied Physics
Fabricating Metamaterials Using the Fiber Drawing Method
Institute of Photonics and Optical Sciences (IPOS), School of Physics, University of Sydney
Metamaterials at terahertz frequencies offer unique opportunities, but are challenging to fabricate in bulk. We adapt the fabrication procedure for microstructured polymer optical fibers to inexpensively fabricate metamaterials potentially on an industrial scale. We produce polymethylmethacrylate fibers containing ~10 μm diameter indium wires separated by ~100 μm, which exhibit a terahertz plasmonic response.
JoVE Immunology and Infection
Saliva, Salivary Gland, and Hemolymph Collection from Ixodes scapularis Ticks
1Microbiology and Pathogenesis Activity, Bacterial Diseases Branch, Division of Vector-Borne Diseases, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, 2Tick-Borne Diseases Activity, Bacterial Diseases Branch, Division of Vector-Borne Diseases, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention
The collection of infected tick hemolymph, salivary glands, and saliva is important to study how tick-borne pathogens cause disease. In this protocol we demonstrate how to collect hemolymph and salivary glands from feeding Ixodes scapularis nymphs. We also demonstrate saliva collection from female I. scapularis adults.
JoVE General
Osmotic Avoidance in Caenorhabditis elegans: Synaptic Function of Two Genes, Orthologues of Human NRXN1 and NLGN1, as Candidates for Autism
1Departamento de Genética, Facultad de Ciencias, Universidad de Córdoba, 2Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC)
Neurexins and neuroligins are membrane-neuron adhesion proteins which perform essential roles in synaptic differentiation and transmission. Neuroligin deficient mutants of C. elegans are defective in detecting osmotic strength, but when they also contain a mutation in the gene coding neurexin, they recover the wild type phenotype.
JoVE General
Herbivore-induced Blueberry Volatiles and Intra-plant Signaling
Department of Entomology, Rutgers University
A push-pull method for collecting plant volatiles is described. The method allows for a comparison of volatiles induced by herbivore feeding, exogenous methyl jasmonate, and mechanical damage. This technique is also used to investigate the volatile response of undamaged branches to exposure to volatiles from herbivore-damaged branches within blueberry plants.
JoVE Neuroscience
Appetitive Associative Olfactory Learning in Drosophila Larvae
1Department of Biology, University of Konstanz, 2Department of Biology, University of Fribourg
Drosophila larvae are able to associate odor stimuli with gustatory reward. Here we describe a simple behavioral paradigm that allows the analysis of appetitive associative olfactory learning.
JoVE Neuroscience
An In Vitro Preparation for Eliciting and Recording Feeding Motor Programs with Physiological Movements in Aplysia californica
1Department of Biology, Case Western Reserve University, 2Department of Neurosciences, Case Western Reserve University, 3Department of Biomedical Engineering, Case Western Reserve University
We describe a technique to extracellularly record and stimulate from nerves, muscles, and individual identified neurons in vitro while eliciting and observing different types of feeding behaviors in the feeding apparatus of Aplysia.
JoVE General
Serial Enrichment of Spermatogonial Stem and Progenitor Cells (SSCs) in Culture for Derivation of Long-term Adult Mouse SSC Lines
Department of Surgery, Weill Cornell Medical College
A simple method to derive and maintain spermatogonial stem and progenitor cell lines from adult mice is presented here. The method utilizes feeder cells originating from the somatic cell compartment of the adult mouse testis. This technique is applicable to common mouse strains, including transgenic, knock-out, and knock-in mice.
JoVE Immunology and Infection
Protocol for Production of a Genetic Cross of the Rodent Malaria Parasites
1National Institute of Allergy and Infectious Diseases, National Institutes of Health, 2School of Life Science, Xiamen University
Genetic crosses of rodent malaria parasites are performed by feeding two genetically distinct parasites to mosquitoes. Recombinant progeny are cloned from mouse blood after allowing mosquitoes to bite infected mice. This video shows how to produce genetic crosses of Plasmodium yoelii and is applicable to other rodent malaria parasites.
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 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 General
Murine Colitis Modeling using Dextran Sulfate Sodium (DSS)
1Department of Cancer Biology, Vanderbilt University, 2Departments of Medicine and Cancer Biology, Vanderbilt University
Dextran sulfate sodium (DSS) administered in the drinking water is an established murine inflammatory injury model of acute colitis. This protocol outlines the method for DSS treatment and the preparation of tissues.
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 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 Immunology and Infection
The Insect Galleria mellonella as a Powerful Infection Model to Investigate Bacterial Pathogenesis
Oral and intra haemocolic infection of larvae of the greater wax moth Galleria mellonella is described. This insect can be used to study virulence factors of entomopathogenic as well as mammalian opportunistic bacteria. Rearing of the insects, methods of infection and examples of in vivo analysis are described.
JoVE General
Testing Nicotine Tolerance in Aphids Using an Artificial Diet Experiment
Boyce Thompson Institute for Plant Research, Cornell University
In this video and assay is demonstrated that tests the tolerance of nicotine to two types of aphids one that infests tobacco plants in the field and one that does not.
JoVE General
Using RNA-mediated Interference Feeding Strategy to Screen for Genes Involved in Body Size Regulation in the Nematode C. elegans
1Department of Science, Borough of Manhattan Community College, City Universtiy of New York (CUNY), 2Department of Biology, Queens College, The City University of New York (CUNY), 3Biochemistry Program, The Graduate Center, Queens College, The City University of New York (CUNY)
We demonstrate how to use the RNAi feeding technique to knock down target genes and score body size phenotype in C. elegans. This method could be used for a large scale screen to identify potential genetic components of interest, such as those involved in body size regulation by DBL-1/TGF-β signaling.
JoVE Clinical and Translational Medicine
Murine Spinotrapezius Model to Assess the Impact of Arteriolar Ligation on Microvascular Function and Remodeling
1Department of Biomedical Engineering, University of Virginia, 2Department of Biomedical Engineering, California Polytechnic State University, 3Office of Animal Welfare, University of Virginia, 4Department of Biomedical Engineering & Institute for Computational Medicine, Johns Hopkins University
We demonstrate a novel arterial ligation model in murine spinotrapezius muscle, including a step-by-step procedure and description of required instrumentation. We describe the surgery and relevant outcome measurements relating to vascular network remodeling and functional vasodilation using intravital and confocal microscopy.
JoVE General
Regular Care and Maintenance of a Zebrafish (Danio rerio) Laboratory: An Introduction
1Centre of Excellence for Alzheimer's Disease Research and Care, School of Medical sciences, Edith Cowan University, 2Centre for Clinical Research in Neuropsychiatry, Graylands Hospital, University of Western Australia, 3McCusker Alzheimer's Research foundation, 4School of Medicine and Pharmacology, University of Western Australia, 5Department of Molecular and Biomedical Sciences, University of Adelaide, 6School of Biomedical Sciences, Curtin University of Technology, 7School of Psychiatry and Clinical Neurosciences, University of Western Australia
This protocol outlines regular maintenance and care to maintain optimal conditions for zebrafish husbandry. The video illustrates the protocol for system maintenance, regular housing, feeding, breeding, and raising of zebrafish larvae.
JoVE Immunology and Infection
Derivation of Thymic Lymphoma T-cell Lines from Atm-/- and p53-/- Mice
Department of Biomedical Sciences, Cornell University
In this video we demonstrate a protocol to establish mouse thymic lymphoma cell lines. By following this protocol, we have successfully established several T-cell lines from Atm-/- and p53-/- mice with thymic lymphoma.
JoVE Neuroscience
Progressive-ratio Responding for Palatable High-fat and High-sugar Food in Mice
CRCHUM and the Montreal Diabetes Research Center, University of Montreal
The present report details the protocol employed to measure the rewarding effects of high-fat food in mice using a progressive ratio operant conditioning task.
JoVE Clinical and Translational Medicine
Hyperinsulinemic-euglycemic Clamps in Conscious, Unrestrained Mice
1Diabetes and Obesity Research Center, Sanford-Burnham Medical Research Institute at Lake Nona, 2Department of Molecular Physiology and Biophysics, Vanderbilt University School of Medicine, 3Vanderbilt Mouse Metabolic Phenotyping Center, Vanderbilt University School of Medicine, 4Department of Pediatrics and Cellular and Integrative Physiology, Indiana University School of Medicine
The hyperinsulinemic-euglycemic clamp, or insulin clamp, is the gold standard for assessing insulin action in vivo. A method for performing insulin clamps in mice is described. This includes a method for arterial catheterization that permits experiments to be performed in conscious, unrestrained mice with minimal stress.
JoVE Neuroscience
Light Preference Assay to Study Innate and Circadian Regulated Photobehavior in Drosophila Larvae
Department of Biology, Institute of Cell and Developmental Biology, University of Fribourg
Here we describe a light-dark preference test for Drosophila larva. This assay provides information about innate and circadian regulation of light sensing and processing photobehavior.
JoVE General
Characterizing Herbivore Resistance Mechanisms: Spittlebugs on Brachiaria spp. as an Example
International Center for Tropical Agriculture, CIAT
This video explains mechanisms of host plant resistance to herbivory and demonstrates a no-choice test that estimates the relative contributions of antibiosis and tolerance to spittlebug resistance in Brachiaria spp.
JoVE General
Experimental Manipulation of Body Size to Estimate Morphological Scaling Relationships in Drosophila
1Department of Biology & Biochemistry, University of Houston, 2Department of Zoology, Michigan State University
Morphological scaling relationships capture and describe organismal shape. We present a method to measure morphological scaling relationships across the natural range of body sizes in fully metamorphic insects. Using a simple diet manipulation we increase the distribution of trait sizes, permitting the accurate description of how shape and size co-vary.
JoVE Neuroscience
Extracellularly Identifying Motor Neurons for a Muscle Motor Pool in Aplysia californica
1Department of Biology, Case Western Reserve University, 2Department of Neurosciences, Case Western Reserve University, 3Department of Biomedical Engineering, Case Western Reserve University
In animals with large identified neurons (e.g. mollusks), analysis of motor pools is done using intracellular techniques1,2,3,4. Recently, we developed a technique to extracellularly stimulate and record individual neurons in Aplysia californica5. We now describe a protocol for using this technique to uniquely identify and characterize motor neurons within a motor pool.
JoVE Neuroscience
Electrode Fabrication and Implantation in Aplysia californica for Multi-channel Neural and Muscular Recordings in Intact, Freely Behaving Animals
1Biology, Case Western Reserve University, 2Neurosciences, Case Western Reserve University, 3Biomedical Engineering, Case Western Reserve University
A technique is described for implanting four in vivo electrodes to monitor the neuromuscular control of feeding behavior in Aplysia californica.
JoVE Neuroscience
Inducing Dendritic Growth in Cultured Sympathetic Neurons
Department of Molecular Biosciences, University of California, Davis
We describe a protocol for using bone morphogenetic protein-7 (BMP-7) or Matrigel to selectively induce dendritic growth in primary sympathetic neurons dissociated from the superior cervical ganglia (SCG) of perinatal rats.
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 Clinical and Translational Medicine
Mesenteric Artery Contraction and Relaxation Studies Using Automated Wire Myography
1Julius L. Chambers Biomedical/Biotechnology Research Institute, North Carolina Central University, Durham, 2Department of Biology, North Carolina Central University, Durham, 3Department of Physiology & Pharmacology and Hypertension & Vascular Research Center, Wake Forest University School of Medicine
An automated myography method for force measurements in isolated mesenteric arteries is described. It employs a Mulvany-Halpern Auto Dual Wire Myograph 510A to determine responses to phenylephrine and extracellular calcium. The method allows consistent determination of isometric responses to agonists in small vessels of diameters of 60 - 300 μm, independently.
JoVE Immunology and Infection
Pseudomonas aeruginosa and Saccharomyces cerevisiae Biofilm in Flow Cells
1Department of Systems Biology, Danish Technical University, 2Department of Biology, University of Copenhagen
Protocol describing the application of a flow cell system for growing and analyzing microbial biofilms for Confocal Laser Scanning Microscopy (CLSM).
JoVE Immunology and Infection
Intravital Microscopy of the Inguinal Lymph Node
1Interdisciplinary Science, University of Northern British Columbia, 2Northern Medical Program, University of Northern British Columbia
A technique for performing intravital microscopy of the inguinal lymph node (LN) is outlined. Such technique allows for real-time, in vivo study of the lymph node microvasculature and structure both during homeostasis and infection. This technique can be adapted to cell trafficking studies and to other lymph node sites.
JoVE Clinical and Translational Medicine
Heterotypic Three-dimensional In Vitro Modeling of Stromal-Epithelial Interactions During Ovarian Cancer Initiation and Progression
1Department of Preventive Medicine, University of Southern California, 2Institute for Women's Health, University College London
We describe methodologies for establishing in vitro heterotypic three-dimensional models comprising ovarian fibroblasts and normal ovarian surface or ovarian cancer epithelial cells. We discuss the use of these models to study stromal-epithelial interactions that occur during ovarian cancer development.
JoVE General
Measuring Caenorhabditis elegans Life Span in 96 Well Microtiter Plates
1Department of Chemical Physiology, The Scripps Research Institute, 2Department of Molecular and Experimental Medicine, The Scripps Research Institute
In this protocol we present a method to measure Caenorhabditis elegans lifespan in 96 well microtiter plates.
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 General
Assessing Murine Resistance Artery Function Using Pressure Myography
In pressure myography, an intact small segment of a vessel is mounted onto two small cannulas and pressurized to a suitable luminal pressure. Here, we describe the method to measure vasorelaxation response of the mouse 3rd order mesenteric arteries in c57 and sGCα1-/- mice using pressure myography.
JoVE General
Protocol for Dengue Infections in Mosquitoes (A. aegypti) and Infection Phenotype Determination
Malaria Research Institute, Bloomberg School of Public Health, Johns Hopkins University
Once a gene is identified as potentially refractory for the dengue virus, it must be evaluated for it's role in preventing viral infections within the mosquito. This protocol illustrates how the extent of dengue infections of mosquitoes can be assayed. The techniques for growing up the virus in culture, membrane feeding mosquitoes human blood, and assaying viral titers in the mosquito midgut are demonstrated.
JoVE Clinical and Translational Medicine
Assessment of Gastric Emptying in Non-obese Diabetic Mice Using a [13C]-octanoic Acid Breath Test
Enteric Neuroscience Program, Department of Physiology and Biomedical Engineering, Mayo Clinic
Determination of gastric emptying with a non-invasive [13C]-octanoic acid breath test for tracking gastroparesis in female NOD LtJ mice.
JoVE General
Manual Restraint and Common Compound Administration Routes in Mice and Rats
1Insourcing Solutions, Charles River, 2Research Models and Services, Charles River
Working safely and humanely with research rodents requires a core competency in handling and restraint methods. This article will present the basic principles required to safely handle and effectively administer compounds to mice and rats.
JoVE General
Preparation of Dissociated Mouse Cortical Neuron Cultures
Department of Anatomy and Neurobiology, University of California, Irvine (UCI)
This video shows a procedure for generating neuronal cultures from late embryo and early postnatal mouse cortex. These cultures can be used for immunocytochemistry, biochemistry, electrophysiology, calcium and sodium imaging and provide a platform to study the neuronal development of transgenic animals that carry a postnatal lethal gene mutation.
JoVE Immunology and Infection
Alphavirus Transducing System: Tools for Visualizing Infection in Mosquito Vectors
Microbiology, Immunology, and Pathology, Colorado State University
Methods for using alphavirus transducing systems to express fluorescent reporters in vitro and in adult mosquitoes are described. This technique may be adapted to express any protein of interest in lieu of or in addition to a reporter.
JoVE Neuroscience
Isolation and Culture of Hippocampal Neurons from Prenatal Mice
Department of Biological Sciences, Auburn University
We provide a protocol for the culture of highly purified hippocampal neurons from prenatal mouse brains without the use of a feeder glial cell layer.
JoVE General
A Practical Approach to Genetic Inducible Fate Mapping: A Visual Guide to Mark and Track Cells In Vivo
1Department of Neuroscience, Division of Biology and Medicine, Brown University, 2Department of Molecular Biology, Cell Biology and Biochemistry, Division of Biology and Medicine, Brown University
Genetic Inducible Fate Mapping (GIFM) marks and tracks cells with fine spatial and temporal control in vivo and elucidates how cells from a specific genetic lineage contribute to developing and adult tissues. Demonstrated here are the techniques required to fate map E12.5 mouse embryos for epifluorescent and explant analysis.
JoVE Neuroscience
A Procedure for Studying the Footshock-Induced Reinstatement of Cocaine Seeking in Laboratory Rats
Psychology, University of Toronto Scarborough
Animal models of relapse, known as reinstatement procedures, have been used extensively to study the role of stress in relapse to drug seeking. Here, we report on a method for inducing the reinstatement of cocaine seeking in laboratory rats via acute exposures to mild, intermittent electric footshock.
JoVE Immunology and Infection
Establishment of Epstein-Barr Virus Growth-transformed Lymphoblastoid Cell Lines
1Stony Brook Children's Hospital, State University of New York at Stony Brook, 2Department of Pediatrics, State University of New York at Stony Brook, 3Department of Molecular Genetics, State University of New York at Stony Brook, 4Department of Microbiology, State University of New York at Stony Brook
We describe a method for generating transformed B cell lines using Epstein-Barr virus. We also illustrate a novel assay that can identify B cells destined to undergo transformation as early as three days after infection.
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