The Journal of Visualized Experiments (JoVE) is a peer reviewed, PubMed-indexed video journal. Our mission is to increase the productivity of scientific research.

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 JoVE Clinical and Translational Medicine

The Spared Nerve Injury (SNI) Model of Induced Mechanical Allodynia in Mice


JoVE 3092 8/18/2011

1The Lundbeck Foundation Research Center MIND, Department of Biomedicine, Aarhus University, 2Department of Pharmacology and Pharmacotherapy, Faculty of Pharmaceutical Sciences, University of Copenhagen

The Spared Nerve Injury animal model is described here as a mouse model of peripheral neuropathic pain following partial denervation of the sciatic nerve by lesioning the tibial and common peroneal nerve branches, leaving the remaining sural nerve intact. Behavioral modification resulting from mechanical allodynia is quantified by von Frey filaments.

 JoVE Clinical and Translational Medicine

Acute and Chronic Tactile Sensory Testing after Spinal Cord Injury in Rats


JoVE 3247 4/04/2012

1Center for Brain and Spinal Cord Repair, School of Allied Medical Professions, The Ohio State University, 2Spinal Cord Research Center, Drexel University College of Medicine

We describe two tactile sensory testing methods for acute or chronic periods of spinal cord injury in rats. These validated procedures can detect the development and maintenance of allodynia-like sensations.

 JoVE Immunology and Infection

Measurement of Tactile Allodynia in a Murine Model of Bacterial Prostatitis


JoVE 50158 1/16/2013

Department of Urology, Northwestern University Feinberg School of Medicine

Infection of the prostate may be a contributing factor in mediating pelvic pain in chronic prostatitis. We describe the procedure for preparation of standardized bacterial inoculum, instillation of bacteria into the urethra of male mice and methodology for measuring tactile allodynia in mice over time.

 JoVE Clinical and Translational Medicine

An Experimental Paradigm for the Prediction of Post-Operative Pain (PPOP)


JoVE 1671 1/27/2010

Department of Anesthesiology and Pain Medicine, University of Washington School of Medicine

Diffuse noxious inhibitory control, temporal summation and wound hyperalgesia testing are demonstrated in the obstetric patient. These tests evaluate inhibitory and excitatory mechanisms of pain processing and are here utilized to evaluate endogenous analgesia at different time-points during pregnancy and the peripartum period to help reveal individual s risk for persistent pain.

 JoVE Clinical and Translational Medicine

Chronic Constriction of the Sciatic Nerve and Pain Hypersensitivity Testing in Rats


JoVE 3393 3/13/2012

School of Medical Sciences, University of New South Wales

Due to the simplicity of surgery and the robust behavioural outcome, chronic constriction of the sciatic nerve is one of the pre-eminent animal models of neuropathic pain. Within 24 hrs following surgery, pain hypersensitivity is established and can be quantitatively measured using a von Frey aesthesiometer (mechanical test) and plantar analgesia meter (thermal test).

 JoVE General

Determining heat and mechanical pain threshold in inflamed skin of human subjects


JoVE 1092 1/14/2009

Department of Anesthesia, Stanford University School of Medicine

Algorithms assessing heat and mechanical pain thresholds in experimentally inflamed skin of human study subjects are shown. The two pain testing paradigms independently examine nociceptive processing by the two major peripheral nerve fiber populations transmitting pain, i.e., non-myelinated C fibers and small myelinated A-delta fibers.

 JoVE Behavior

Use of the Operant Orofacial Pain Assessment Device (OPAD) to Measure Changes in Nociceptive Behavior


JoVE 50336 6/10/2013

1Department of Oral and Maxillofacial Surgery, University of Florida College of Dentistry, 2Department of Neuroscience, McKnight Brain Institute, University of Florida College of Medicine, 3Stoelting Co., 4Department of Orthodontics, University of Florida

We present a user-friendly, high-throughput operant system for the evaluation of pain behaviors in awake, conscious rodents. The Orofacial Pain Assessment Device (OPAD) can assess pain through a reward/conflict paradigm thus providing a more humane way of testing. This protocol will yield more clinically relevant and translational data from rodents.

 JoVE Bioengineering

Determination of the Transport Rate of Xenobiotics and Nanomaterials Across the Placenta using the ex vivo Human Placental Perfusion Model


JoVE 50401 6/18/2013

1Department of Obstetrics, Perinatal Pharmacology, University Hospital Zurich, 2Laboratory for Materials - Biology Interactions, EMPA Swiss Federal Laboratories for Materials Testing and Research, 3Graduate School for Cellular and Biomedical Sciences, University of Bern

The ex vivo dual recirculating human placental perfusion model can be used to investigate the transfer of xenobiotics and nanoparticles across the human placenta. In this video protocol we describe the equipment and techniques required for a successful execution of a placenta perfusion.

 JoVE General

Polymerase Chain Reaction: Basic Protocol Plus Troubleshooting and Optimization Strategies


JoVE 3998 5/22/2012

Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles

PCR has emerged as a common technique in many molecular biology laboratories. Provided here is a quick guide to several conventional PCR protocols. Because each reaction is a unique experiment, optimal conditions required to generate a product vary. Understanding the variables in a reaction will greatly enhance troubleshooting efficiency, thereby increasing the chance to obtain the desired result.

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 JoVE Bioengineering

Induction of Adhesion-dependent Signals Using Low-intensity Ultrasound


JoVE 4024 5/08/2012

1School of Biochemistry, University of Bristol, 2Smith and Nephew

This protocol describes the stimulation of cultured fibroblasts with low-intensity pulsed ultrasound, which drives focal adhesion formation and Rac1 activation by mimicking engagement of the transmembrane matrix receptor, syndecan-4. This approach allows investigation of a successful clinical technique at the cellular level, thereby providing opportunities for refinement of the therapy.

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 JoVE Clinical and Translational Medicine

Intranasal Administration of CNS Therapeutics to Awake Mice


JoVE 4440 4/08/2013

Alzheimer’s Research Center at Region’s Hospital, HealthPartners Institute for Education and Research

A method to intranasally administer drugs to awake mice for the purpose of targeting the brain is described. This method allows for repeat dosing over long periods using intranasal administration of drug without anesthesia, and nose-to-brain delivery with minimal systemic exposure.

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 JoVE Neuroscience

Patch-clamp Capacitance Measurements and Ca2+ Imaging at Single Nerve Terminals in Retinal Slices


JoVE 3345 1/19/2012

The Vollum Institute, Oregon Health and Science University

Here we describe a protocol for the preparation of agar-embedded retinal slices that are suitable for electrophysiology and Ca2+ imaging. This method allows one to study ribbon-type synapses in retinal microcircuits using direct patch-clamp recordings of single presynaptic nerve terminals.

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 JoVE General

Presynaptically Silent Synapses Studied with Light Microscopy


JoVE 1676 1/04/2010

1Department of Psychiatry, Washington University School of Medicine, 2Department of Anatomy, Washington University School of Medicine, 3Department of Neurobiology, Washington University School of Medicine

Glutamatergic synapses can switch from an active mode to a silent mode. We demonstrate that presynaptic activity status in dissociated culture of rodent neurons is visualized using a fixable form of the FM1-43 dye to visualize active synapses and immunostaining with vGluT-1 antibody to visualize all glutamate synapses.

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 JoVE General

Generation of Human CD40-activated B cells


JoVE 1373 10/16/2009

Laboratory for Tumor and Transplantation Immunology and Stem Cell Transplantation Program, University Hospital of Cologne, Department I of Internal Medicine

In this video we present the ex vivo generation and expansion of human CD40-activated B cells (CD40-B) from peripheral blood mononuclear cells (PBMC) by stimulation with CD40 ligand and interleukin-4.

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 JoVE Clinical and Translational Medicine

A Murine Model of Stent Implantation in the Carotid Artery for the Study of Restenosis


JoVE 50233 5/14/2013

1Institute for Molecular Cardiovascular Research, RWTH Aachen University, 2Institute for Textile Technology and Mechanical Engineering, RWTH Aachen University, 3Institute for Applied Medical Engineering, Helmholtz-Institute of RWTH Aachen University, 4Department of Experimental Molecular Imaging, RWTH Aachen University, 5Department of Oral and Maxillofacila Surgery, RWTH Aachen University

A model of stent implantation in mouse carotid artery is described. Compared to other similar methods, this procedure is very rapid, simple and accessible, offering the possibility to study in a convenient way the vascular wall reaction to different drug-eluting stents and the molecular mechanisms of restenosis.

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 JoVE Immunology and Infection

Murine Model of CD40-activation of B cells


JoVE 1734 3/05/2010

Laboratory for Tumor and Transplantation Immunology, Department I of Internal Medicine, University Hospital of Cologne

In this video, we demonstrate the procedure of CD40-activation and expansion of murine B cells from splenocytes of C57BL/6 mice, which can be used as a model antigen-presenting cell (APC) to study induction of immunity.

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 JoVE Clinical and Translational Medicine

A Mouse Model of the Cornea Pocket Assay for Angiogenesis Study


JoVE 3077 8/18/2011

National Eye Institute

The cornea is unique in that it lacks vascular tissues. However, robust blood vessel growth and survival can be induced in the cornea by potent angiogenic factors. Therefore, the cornea can provide with us a valuable tool for angiogenic studies. This protocol demonstrates how to perform the mouse model of cornea pocket assay and how to assess the angiogenesis induced by angiogenic factors using this model.

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 JoVE General

Platelet Adhesion and Aggregation Under Flow using Microfluidic Flow Cells


JoVE 1644 10/27/2009

Fluxion Biosciences, Inc.

The platelet adhesion cascade takes place in the presence of shear flow, a factor not accounted for in conventional (static) well-plate assays. This article reports on a platelet-aggregation assay utilizing a microfluidic well-plate format to emulate physiological shear flow conditions.

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 JoVE General

GC-based Detection of Aldononitrile Acetate Derivatized Glucosamine and Muramic Acid for Microbial Residue Determination in Soil


JoVE 3767 5/19/2012

1DOE-Great Lakes Bioenergy Research Center, University of Wisconsin, Madison, 2Department of Soil Science, University of Wisconsin, Madison, 3Department of Soil and Water Science, University of Florida

We describe a method protocol for the GC-based analysis of the aldonitrile acetate derivatives of glucosamine and muramic acid extracted from soil. For elucidation of the chemical mechanism, we also present a strategy to confirm the structure of the derivative and the ion fragments formed upon electron ionization.

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 JoVE Clinical and Translational Medicine

Collection Protocol for Human Pancreas


JoVE 4039 5/23/2012

Department of Pathology, Immunology, and Laboratory Medicine, University of Florida

This video demonstrates a dissection procedure for processing human pancreas into multiple storage formats. Anatomical orientation is maintained throughout the pancreatic regions to allow definition of regional islet composition and density.

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 JoVE Neuroscience

Stereotaxic Surgery for Excitotoxic Lesion of Specific Brain Areas in the Adult Rat


JoVE 4079 7/19/2012

1Helen Wills Neuroscience Institute, University of California Berkeley, 2Office of Laboratory Animal Care, University of California Berkeley, 3McGovern Institute for Brain Research & The Department of Brain and Cognitive Science, Massachusetts Institute of Technology, 4Integrative Biology Department, University of California Berkeley

Targeted ablation of specific brain region(s) by infusion of an excitotoxin using stereotaxic coordinates is described. This technique could also be adapted for infusion of other chemicals into the rat brain.

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 JoVE Immunology and Infection

Intravital Imaging of the Mouse Popliteal Lymph Node


JoVE 3720 2/08/2012

1Department of Pediatrics, Case Western Reserve University, 2Department of Pediatrics, Pathology and Biomedical Engineering, Case Western Reserve University

Recent advances in 2-photon microscopy have enabled real-time in situ imaging of live tissues in animal models, thereby enhancing our ability to investigate cellular behavior in both physiologic and pathologic conditions. Here, we outline the preparations required to perform intravital imaging of the mouse popliteal lymph node.

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 JoVE General

Avidity-based Extracellular Interaction Screening (AVEXIS) for the Scalable Detection of Low-affinity Extracellular Receptor-Ligand Interactions


JoVE 3881 3/05/2012

Cell Surface Signalling Laboratory, Wellcome Trust Sanger Institute

AVEXIS is a high throughput protein interaction assay developed to systematically screen for novel extracellular receptor-ligand pairs involved in cellular recognition processes. It is specifically designed to detect transient protein interactions that are difficult to identify using other high throughput approaches.

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 JoVE General

Peptides from Phage Display Library Modulate Gene Expression in Mesenchymal Cells and Potentiate Osteogenesis in Unicortical Bone Defects


JoVE 2362 12/10/2010

1Orthopaedics Research, University of Virginia, 2Biological Sciences, University of Delaware, 3Orthopaedic Surgery, University of Virginia

A phage display library was used to identify peptide sequences that target bone. The objective was to investigate the effect of these peptides on mesenchymal cell differentiation and to determine their effect on bone regeneration.

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 JoVE General

In vivo Ca2+- Imaging of Mushroom Body Neurons During Olfactory Learning in the Honey Bee


JoVE 1353 8/18/2009

1Institut für Biologie - Neurobiologie, Freie Universität Berlin, 2Institut für Biologie - Neurobiologie, Free University Berlin - Freie Universitaet Berlin

Bees can be conditioned in an appetitive olfactory learning paradigm (PER-conditioning). Using odors as stimuli, we established a method in which behavior is recorded while simultaneously Calcium Imaging is used to measure odor evoked activity in mushroom body neurons in vivo.

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 JoVE General

Isolation and Genetic Manipulation of Adult Cardiac Myocytes for Confocal Imaging


JoVE 1433 9/17/2009

Institute for Molecular Cell Biology, Universty of Saarland

Adult cardiac myocytes are primary cells that can be isolated from animal hearts and cultured for several days. Within this culture period adenoviral gene transfer can be used to express genetically encoded biosensors (GEBs) or fluorescent fusion proteins. Both approaches allow cellular investigations by means of confocal microscopy.

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 JoVE General

Analyzing Gene Expression from Marine Microbial Communities using Environmental Transcriptomics


JoVE 1086 2/18/2009

Department of Marine Sciences, University of Georgia (UGA)

We present a method for generating cDNA from environmental mRNA. In general, total RNA is first collected from the environment, rRNA is selectively removed, mRNA is selectively amplified, and cDNA synthesized from the enriched mRNA pool is sequenced. Recovered sequences can be annotated using standard bioinformatics techniques to identify the expressed genes.

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 JoVE General

Pouring and Running a Protein Gel by reusing Commercial Cassettes


JoVE 3465 2/12/2012

1Department of Biology, University of Florida, 2UF Genetics Institute, University of Florida, 3Plant Molecular & Cellular Biology Program, University of Florida

Our protocol demonstrates how to pour multiple protein gels at a time by recycling Invitrogen Nupage Novex minigel cassettes, and inexpensive materials purchased at a home improvement store. This economical and streamlined method includes a way to store the gels at 4°C for a few weeks. By re-using the plastic gel cassettes from commercially available gels, labs that run frequent protein gels can save significant costs and help the environment.

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 JoVE Neuroscience

Studying the Neural Basis of Adaptive Locomotor Behavior in Insects


JoVE 2629 4/13/2011

Zoological Institute, University of Cologne

We describe a method to record motor activity, timed to the electrically recorded tarsal contact signal in a tethered insect, walking on a slippery surface. This is used to study the neural basis of adaptive behavior under reduced influence of mechanical interaction between legs through the substrate.

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 JoVE General

FRET Microscopy for Real-time Monitoring of Signaling Events in Live Cells Using Unimolecular Biosensors


JoVE 4081 8/20/2012

Emmy Noether Group of the DFG, Department of Cardiology and Pneumology, European Heart Research Insitute Göttingen, Georg August University Medical Center, Göttingen, Germany

Förster resonance energy transfer (FRET) microscopy is a powerful technique for real-time monitoring of signaling events in live cells using various biosensors as reporters. Here we describe how to build a customized epifluorescence FRET imaging system from commercially available components and how to use it for FRET experiments.

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 JoVE Neuroscience

Imaging pHluorin-tagged Receptor Insertion to the Plasma Membrane in Primary Cultured Mouse Neurons


JoVE 4450 11/20/2012

The Jackson Laboratory

By tagging the extracellular domains of membrane receptors with superecliptic pHluorin, and by imaging these fusion receptors in cultured mouse neurons, we can directly visualize individual vesicular insertion events of the receptors to the plasma membrane. This technique will be instrumental in elucidating the molecular mechanisms governing receptor insertion to the plasma membrane.

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 JoVE General

Undecalcified Bone Preparation for Histology, Histomorphometry and Fluorochrome Analysis


JoVE 1707 1/08/2010

1Monash Immunology and Stem Cell Laboratories, Monash University, 2Anatomy and Developmental Biology, Monash University

Undecalcified bone histology provides important information for a variety of clinical and research applications. It is technically challenging, particularly with large size specimens. This video illustrates the process of producing good quality sections and demonstrates the technical difficulties and methods with which to overcome them.

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 JoVE Immunology and Infection

Direct Observation of Phagocytosis and NET-formation by Neutrophils in Infected Lungs using 2-photon Microscopy


JoVE 2659 6/02/2011

1Institute for Molecular and Clinical Immunology, Otto-von-Guericke University Magdeburg, 2Department of Immunoregulation, Helmholtz Center for Infection Research

We show, how to use 2-photon microscopy for the observation of the dynamics of neutrophil granulocytes in infected lungs while they phagocytose pathogens or produce neutrophil extracellular traps (NETs).

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 JoVE Clinical and Translational Medicine

Functional Assessment of Intestinal Motility and Gut Wall Inflammation in Rodents: Analyses in a Standardized Model of Intestinal Manipulation


JoVE 4086 9/11/2012

Department of Surgery, University of Bonn

Postoperative ileus (POI) is a complication of abdominal surgery leading to increased morbidity and a prolonged hospital stay. Because prophylactic or therapeutic strategies are lacking intensified research is necessary. Therefore we established a standardized and feasible mouse model to investigate the pathophysiology of POI and to study potential therapeutic options.

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 JoVE Clinical and Translational Medicine

Orthotopic Small Bowel Transplantation in Rats


JoVE 4102 11/06/2012

1Department of Surgery, University of Bonn, Germany, 2Department of Surgery, Kyoto University Hospital

Small bowel transplantation has become an accepted treatment option for patients with irreversible intestinal failure. Our experimental model of orthotopic small bowel transplantation in rats serves as a reliable tool to address underlying immunologic and inflammatory processes that complicate intestinal transplantation.

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 JoVE Immunology and Infection

Purification of Pathogen Vacuoles from Legionella-infected Phagocytes


JoVE 4118 6/19/2012

Max von Pettenkofer-Institut, Ludwig-Maximilians-Universität

This article describes a method for the isolation and purification of intact Legionella-containing vacuoles (LCVs) from amoeba and macrophages. The two-step protocol comprises LCV enrichment by immuno-magnetic separation using an antibody against a bacterial LCV marker and further purification by density gradient centrifugation.

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 JoVE Immunology and Infection

Flow Cytometric Isolation of Primary Murine Type II Alveolar Epithelial Cells for Functional and Molecular Studies


JoVE 4322 12/26/2012

1Research Group Immune Regulation, Helmholtz Centre for Infection Research, 2Research Group Infection Immunology, Institute of Medical Microbiology, Otto-von-Guericke University, 3Department of Experimental Immunology, Helmholtz Centre for Infection Research

We describe the rapid isolation of primary murine type II alveolar epithelial cells (AECII) by flow cytometric negative selection. These AECII show high viability and purity and are suitable for a wide range of functional and molecular studies regarding their role in respiratory conditions such as autoimmune or infectious diseases.

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 JoVE Bioengineering

Engineering a Bilayered Hydrogel to Control ASC Differentiation


JoVE 3953 5/25/2012

1Department of Extremity Trauma Research and Regenerative Medicine, United States Army Institute of Surgical Research, 2Department of Biomedical Engineering, The University of Texas at Austin

This protocol focuses on utilizing the inherent ability of stem cells to take cue from their surrounding extracellular matrix and be induced to differentiate into multiple phenotypes. This methods manuscript extends our description and characterization of a model utilizing a bilayered hydrogel, composed of PEG-fibrin and collagen, to simultaneously co-differentiate adipose-derived stem cells1.

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 JoVE Clinical and Translational Medicine

Programmed Electrical Stimulation in Mice


JoVE 1730 5/26/2010

1Department of Molecular Physiology and Biophysics, Baylor College of Medicine (BCM), 2The Margaret M. and Albert B. Alkek Department of Medicine, Baylor College of Medicine (BCM)

Programmed electrical stimulation provides the ability to determine conduction properties of the heart, and the possibility to induce and terminate cardiac arrhythmias using various pacing protocols. Using a transvenous catheter, intracardiac electrogram recordings can be obtained in mice following programmed electrical stimulation protocols to identify arrhythmogenic substrates.

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 JoVE General

Live Imaging of Cell Motility and Actin Cytoskeleton of Individual Neurons and Neural Crest Cells in Zebrafish Embryos


JoVE 1726 2/03/2010

1Genetics Training Program, University of Wisconsin-Madison, 2Department of Anatomy, University of Wisconsin-Madison, 3Department of Zoology, University of Wisconsin-Madison, 4Cell and Molecular Biology Training Program, University of Wisconsin-Madison

This protocol describes imaging of individual neurons or neural crest cells in living zebrafish embryos. This method is used to examine cellular behaviors and actin localization using fluorescence confocal time-lapse microscopy.

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 JoVE General

Analysis of Physiologic E-Selectin-Mediated Leukocyte Rolling on Microvascular Endothelium


JoVE 1009 2/11/2009

1Department of Dermatology, Brigham and Women's Hospital, 2Department of Dermatology, Brigham and Women's Hospital and Harvard Medical School

This report provides a visual depiction of parallel-plate flow chamber analysis for studying leukocyte endothelial interactions under physiologic shear stress. This method is particularly useful for investigating the role of endothelial (E)-selectin and leukocyte E-selectin ligands that trigger leukocyte rolling on endothelial cell surfaces.

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 JoVE General

Genetic Studies of Human DNA Repair Proteins Using Yeast as a Model System


JoVE 1639 3/18/2010

Laboratory of Molecular Gerontology, National Institute on Aging, NIH

Genetic studies in yeast can be employed to investigate the molecular and cellular functions of human genes in cellular DNA metabolism. Methods are described for the genetic characterization of the human WRN gene product defective in the premature aging disorder Werner syndrome in functionally conserved pathways using yeast as a tractable model system.

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 JoVE General

Electrospinning Fibrous Polymer Scaffolds for Tissue Engineering and Cell Culture


JoVE 1589 10/21/2009

Department of Bioengineering, University of Pennsylvania

The process of electrospinning polymers for tissue engineering and cell culture is addressed in this article. Specifically, the electrospinning of photoreactive macromers with additional processing capabilities of photopatterning and multi-polymer electrospinning is described.

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