<h2 class="jove_title"><a href="https://www.jove.com/video/3646">Silk Fibroin Film Culture System for In vitro Analysis and Biomaterial Design</a></h2>
Brian D. Lawrence1, Zhi Pan2, 1, Michael D. Weber1, David L. Kaplan3, Mark I. Rosenblatt1 1Margaret M. Dyson Vision Research Institute, Weill Cornell Medical College , 21Margaret M. Dyson Vision Research Institute, Weill Cornell Medical College , 3Department of Biomedical Engineering, Tufts University
Silk films are a novel class of biomaterials readily customizable for an array of biomedical applications. The presented silk film culture system is highly adaptable to a variety of in vitro analyses. This system represents a biomaterial design platform offering in vitro optimization before direct translation to in vivo models.
<h2 class="jove_title"><a href="https://www.jove.com/video/3666">Induction of Myocardial Infarction in Adult Zebrafish using Cryoinjury</a></h2>
Fabian Chablais, Anna Ja&#378;wi&#324;ska Department of Biology, Unit of Zoology, University of Fribourg, Fribourg, Switzerland
Zebrafish represents a valuable model to study the mechanisms of heart regeneration in vertebrates. Here, we present a protocol for induction of a heart infarct in adult zebrafish using cryoinjury. This method results in massive cell death within 20% of the ventricular wall, similar to that observed in mammalian infarcts.
<h2 class="jove_title"><a href="https://www.jove.com/video/3680">Segmentation and Measurement of Fat Volumes in Murine Obesity Models Using X-ray Computed Tomography</a></h2>
Todd A. Sasser1, Sarah E. Chapman2, Shengting Li1, Caroline Hudson2, Sean P. Orton1, Justin M. Diener3, Seth T. Gammon1, Carlos Correcher4, W. Matthew Leevy2 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.
<h2 class="jove_title"><a href="https://www.jove.com/video/3793">Stereotactic Radiosurgery for Gynecologic Cancer </a></h2>
Charles Kunos1, James M. Brindle1, Robert Debernardo2 1Department of Radiation Oncology, University Hospitals Case Medical Center and Case Western Reserve University School of Medicine, 2Department of Obstetrics and Gynecology, Division of Gynecologic Oncology, University Hospitals Case Medical Center and Case Western Reserve University School of Medicine
Stereotactic body radiotherapy (SBRT) involves image-guided, ablative radiation delivered to cancer targets refractory to chemotherapy or to conventional radiation treatment. The robotic-armed Cyberknife SBRT system, using sophisticated target localization, delivers hypofractionated radiation doses capable of sterilizing cancer targets. This article will consider new therapeutic roles of SBRT for gynecological cancers.
<h2 class="jove_title"><a href="https://www.jove.com/video/3992">Establishment of Microbial Eukaryotic Enrichment Cultures from a Chemically Stratified Antarctic Lake and Assessment of Carbon Fixation Potential</a></h2>
Jenna M. Dolhi, Nicholas Ketchum, Rachael M. Morgan-Kiss Department of Microbiology, Miami University 
Microbial eukaryotes are both a source of photosynthetically-derived carbon and top predatory species in permanently ice-covered Antarctic lakes. This report describes an enrichment culture approach to isolate metabolically versatile microbial eukaryotes from the Antarctic lake, Lake Bonney, and assesses inorganic carbon fixation potential using a radioisotope assay for Ribulose-1,5-bisphophate carboxylase oxygenase (RubisCO) activity.
<h2 class="jove_title"><a href="https://www.jove.com/video/4008">Retrograde Loading of Nerves, Tracts, and Spinal Roots with Fluorescent Dyes</a></h2>
Dvir Blivis, Michael J. O&#39;Donovan Developmental Neurobiology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health
We describe a simple and low cost technique for introducing high concentration of fluorescent and calcium-sensitive dyes into neurons or any neuronal tract using a polyethylene suction pipette.
<h2 class="jove_title"><a href="https://www.jove.com/video/3823">A Primary Neuron Culture System For The Study Of Herpes Simplex Virus Latency And Reactivation</a></h2>
Mariko Kobayashi1, Ju-Youn Kim1, Vladimir Camarena2, Pamela C. Roehm3, Moses V. Chao4, 2, 5, 6, 7, Angus C. Wilson1, Ian Mohr1 1Department of Microbiology, New York University School of Medicine, 2Molecular Neurobiology Program, Skirball Institute for Biomolecular Medicine, New York University School of Medicine, 3Department of Otolaryngology, New York University School of Medicine, 4Department of Cell Biology, New York University School of Medicine, 5Department of Physiology and Neuroscience, New York University School of Medicine, 6Department of Psychiatry, New York University School of Medicine, 7Center for Neural Science, New York University School of Medicine
The protocol describes an efficient and reproducible model system to study herpes simplex virus type 1 (HSV-1) latency and reactivation. The assay employs homogenous sympathetic neuron cultures and allows for the molecular dissection of virus-neuron interactions using a variety of tools including RNA interference and expression of recombinant proteins.

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april 2012: this month in jove

The April issue of the Journal of Visualized Experiments (JoVE) includes an article that follows a lab from the University of Miami of Ohio to Lake Bonney - a permanently ice-covered saline lake in Antarctica. Few organisms can survive the harsh conditions under the ice, where light, warmth, and carbon sources are in very short supply. Single celled microorganisms called protists are the major class of microbes living beneath Lake Bonney, and are capable of bringing carbon, via photosynthesis, into the circle of life.
After determining the appropriate sampling site, our authors drill and melt through the ice so that they can collect samples from various depths within the lake&#x2019;s chemically stratified water column. Once collected, samples are taken to a field laboratory for filtration and stabilization. After processing, microbes present in the water sample are cultured for further experimentation. For example, our authors show that their enrichment cultures retain photosynthetic activity, and future experiments should help better understand protist physiology, as well as how such organisms can affect global geochemical cycling.
In Clinical and Translational Medicine, JoVE turns its attention to stereotactic body radiotherapy, or SBRT, for the treatment of gynecological tumors. SBRT is a minimally invasive form of cancer treatment that relies on radiation, delivered by a linear accelerator mounted on a robotic arm, to biologically inactivate tumors.
Our authors, from Case Medical Center, explain how gold soft tissue fiducial markers are placed around the cancer target at various depths based on computed tomography imaging. During a treatment planning session, CT and PET images are taken and then co-registered. Guided by these images, both radiation and gynecological oncologists designate the cancer volumes that will be targeted during therapy as well as contour surrounding normal structures that should be left unharmed. At the start of treatment, a target localizing system detects the fiducial markers via cross-plane radiographic imaging and marker location is compared with previously obtained imaging data.
During treatment, light emitting diodes track a patient&#x2019;s movement, in order to correlate their breathing pattern to the location of the fiducial markers, so that radiation can be delivered accurately. Overcoming the complications associated with patient immobilization, our authors show that their procedure for stereotaxic body radiotherapy can precisely deliver radiation to the target volume while limiting dosage to nearby structures.
In our Bioengineering section, JoVE presents an article, which involves making biocompatible substrates from silkworm cocoons. First, cocoons are screened for contamination and processed so that silk extract is produced. Extract is placed atop a PDMS mold, which has been designed to create a pattern in the silk film drying on its surface. Once dried, the silk film is subjected to a process referred to as water annealing, which renders the film transparent and perfect for microscopy. Following cell seeding on the films, our authors show that tracking cell migration on the micro-patterned silk substrate is just as easy as on more conventional tissue culture surfaces. The biocompatibility of silk films as well as their potential to be chemically and structurally modified makes them attractive candidate materials for in vivo applications, like medical device design.
Surprisingly, primary neuronal culture makes its way into our Immunology and Infection section, because this April, JoVE documents an innovative primary sympathetic neuron culture system used to study herpes simplex virus latency and activation.
Peripheral neurons act like reservoirs for the herpes virus that are the source of reactivation events. To establish a peripheral neuron culture, superior cervical ganglia are isolated from embryonic mice and following digestion and dissociation are plated in 96 well plates. At around day 6 in vitro, herpes viruses encoding a viral-GFP fusion protein are added to the cells along with an inhibitor of lytic replication. Upon inhibitor withdrawal, latent virus will reactivate and GFP expression will be observable via fluorescent microscopy. By counting the number of wells exhibiting GFP fluorescence, the ability of small molecules or gene silencing oligonucleotides to either suppress or induce viral reactivation can be tested, making this assay a potential tool to uncover new therapeutics to help manage HSV-1 infection.
This brief summary describes only four of the fifty articles JoVE will release in April. Other notable releases include methods for quantifying obesity in rats using x-ray computed tomography, inducing myocardial infarction in the zebrafish heart, and retrograde labeling of the excised spinal cord. Stay tuned.

Watch this Scientific Journal Video about April 2012: This Month in JoVE at JoVE.com

April 2012: This Month in JoVE

04 2012: Este mes en Jove

The April issue of the Journal of Visualized Experiments (JoVE) includes an article that follows a lab from the University of Miami of Ohio to Lake Bonney ...

Research

JoVE Journal

Biology

Video: April 2012: This Month in JoVE

August 2012: This Month in JoVE

Traditional microscopy requires lens objectives to magnify specimens, and can involve numerous optical components like additional objectives, filters, and mirrors to refract and direct light to optical sensors. The August 2012 issue of JoVE (Journal of Visualized Experiments) is marked by the third publication from the Ozcan Lab (University of California, Los Angeles) on their lens free lens-free "on-chip" microscopy platform, which they have pioneered.
Back in 2009, the Ozcan lab published their first article, which demonstrated the use of a lens-free imaging platform that could image cells within whole blood. This imaging technique involves placing a sample directly on an optoelectric sensor array, like the CCD or CMOS chips found in the standard camcorder. Then, LED illumination from above the sample casts shadows on the chip, which are recorded as digital holograms that can be subjected to image processing. Not only does this lensless imaging system allow for an extremely large field of view (FOV of 0.6-8 cm2), the lack of bulky optical components makes it excellent for microfluidic applications. The Ozcan group demonstrates this in their follow-up 2011 JoVE article, in which fluorescently labeled white blood cells are imaged within a microfluidic chip.
This August in JoVE, the Ozcan group demonstrates further advancements to their lens-free microscopy platform by applying it to tomographic imaging of the nematode, C. elegans. By changing the angle of illumination, using a motorized rotation stage, the Ozcan group shows how multiple holographic slices may be generated for a sample-which, following processing, can be combined into tomograms. The Ozcan group confirms that their 3D reconstruction of the worm is successful by citing that the pharyngeal tube, a 5-micron-thick structure, is only visible in a single slice and in a 3D reconstructed cross section.
The compact and inexpensive nature of the lens-free imaging systems - designed and assembled by the Ozcan group - make them well suited for point-of-care diagnostic applications, or even cell phone based microscopy that can be performed in the field.
At the Ernest Gallo Clinic and Research Center at University of California, San Francisco JoVE learns how to visualize morphological changes in single cells using three-dimensional fluorescence microscopy and computer analysis. In this procedure, cells are given agonist, antagonist plus agonist, or no treatment, and prepared for immunofluorescence microscopy. Three-dimensional images are acquired with the help of a two-photon laser system, and the fluorescence data are processed on the computer using Imaris and Matlab.
To demonstrate the power of this technique, our authors quantify single-cell phenotypic changes in transfected HEK293 cells. Three-dimensional morphometric analysis shows dramatic changes in cells treated with agonist. These changes are not always apparent when using conventional 2D analysis. This technique allows morphological changes in single cells to be quantified and characterized in response to pharmacologic stimuli, offering a powerful new assessment tool to the arsenal of drug discovery research.
This month, in JoVE Applied Physics, we travel to South Carolina to visit the School of Materials Science and Engineering at Clemson University. Here, researchers show us how to construct lithium batteries for laboratory research.
The basic components of a lithium coin cell are the working electrode, the lithium electrolyte, and a lithium foil counter electrode. The different components of the coin cell are carefully assembled and sealed with a crimping machine. The finished coin cell can then be characterized in a battery tester. Using their homemade coin cells, our researchers can experiment with using different materials to make the cathodes of lithium coin cells.
This month in JoVE Immunology and Infection, we head to Basel, Switzerland to witness two techniques for diagnosing helminth infections. We also see how investigators perform the shuttle run test in children, in order to assess the effects of these infections on physical fitness.
Helminths are parasitic worms that can live inside humans and animals. Many species infect the intestinal tract, and may be transmitted through soil. Our authors demonstrate the Kato-Katz technique, which is used for diagnosing several common soil-transmitted helminths. They also demonstrate the Baermann technique, which uses light to stimulate the migration of certain types of phototactic helminths out of sample preparations. The various types of helminth species can subsequently be determined based on morphology.
Our authors then demonstrate how to set up and perform a 20-meter shuttle run test for children, and to measure the impact of helminth infections on physical fitness. This method can help determine the true burden of soil-transmitted helminth infections on overall health.
This brief summary highlights but a few notable video-articles that will be released in August. We'll also feature articles that demonstrate how to express genes in the midbrain of the chick embryo, study neutrophil transmigration in parallel flow chambers lined with endothelial cells, and precisely measure proteolytic degradation of the extracellular matrix.

Traditional microscopy requires lens objectives to magnify specimens, and can involve numerous optical components like additional objectives, filters, and mirrors to refract and direct light to optical sensors. The August 2012 issue of JoVE (Journal of Visualized Experiments) is marked by the third publication from the Ozcan Lab (University of California, Los Angeles) on their lens-free "on-chip" microscopy platform, which they have pioneered.

08 2012: Este mes en Jove

Traditional microscopy requires lens objectives to magnify specimens, and can involve numerous optical components like additional objectives, filters, and ...

Investigación

Biología

2012: A Year In Review

Here's a look at some of the milestones and highlights of the year 2012 in Journal of Visualized Experiments (JoVE).
At the start of 2012, JoVE reached a major milestone by publishing our 1500th article. In this publication, in JoVE Bioengineering, Yu et al. described a method for analyzing the free radical composition of cigarette smoke. This method simulated cigarette puffing with a single-port smoking device, and combined it with electron spin resonance (ESR) spectroscopy to measure the degree to which antioxidant compounds can scavenge free radicals in cigarette smoke. A possible outcome of this research is the creation of less harmful cigarettes.
JoVE Bioengineering also contained the most-viewed article of 2012. Owczarczak et al. described a method for hacking a standard inkjet printer, loading ink cartridges with a cell-suspension "bioink," and printing lines of live cells onto glass slides. The thermal inkjet printing process creates temporary pores in the cell membrane, visualized by the incorporation of fluorescently labeled actin monomers. This concept, called "bioprinting," has many potential applications in cell and tissue engineering.
Also in 2012, JoVE Bioengineering featured a protocol by Hsia et al. for isolating and purifying spider silk protein, spinning it into fibers, and assessing the fiber strength. This protocol for laboratory-scale production of spider silk, which is stronger than tensile steel, can potentially be extended to large-scale manufacturing.
In JoVE Clinical and Translational Medicine, we featured a number of articles related to stroke, one of which. In one article, M&ouml;bius-Winkler et al. demonstrated placement of the WATCHMAN left atrial appendage occlusion device from Boston Scientific. This device is designed to prevent strokes by trapping clots within the left atrial appendage of the heart before they exit. Our authors demonstrated how to insert the guide wire through the femoral artery into the heart, advance the device into the left atrium, and deploy the device in the left atrial appendage.
Another article focused on stroke, Hamel et al. described the use of a driving simulator to study how patients compensate for visual field defects following stroke. By analyzing the compensatory gaze behavior of patients as they navigated through virtual driving courses with varying degrees of complexity, our authors see great potential for the use of driving simulators in stroke rehabilitation.
In JoVE Immunology and Infection, we published an article by Keyel et al. describing the real-time kinetics of immune cell responses to bacterial toxins using live cell microscopy. Combined with high-speed 3D confocal microscopy, this technique can also visualize the cellular repair response.
Also in JoVE Immunology and Infection, we featured an article by Yap et al. describing methods for diagnosing helminth infections in children. Helminths are parasitic worms that can infect the intestinal tract of humans and animals, and may be distinguished based on their morphology. The same article demonstrated how to measure the impact of helminth infections on physical fitness in children, which is a measure of overall health.
In JoVE Neuroscience, we featured a method by Hoffmann et al., who used tiny headphones to alter the auditory feedback in songbirds, and analyzed the computational and neurophysiological basis of vocal learning in birds when they adjust their singing in response to altered acoustic signals.
Also in JoVE Neuroscience, we moved from birds to bees with a method that assesses associative and non-associative tactile learning in honeybees. This method, by Mujagi&#263; et al., allowed bees to scan different metal surfaces with their antennae, then conditioned them to expect sugar water when their antennae touched particular surfaces, and analyzed the corresponding changes in antennal movement.
In 2012, we launched a brand-new section: JoVE Applied Physics, which features articles on subjects ranging from plasma physics to material science. The Applied Physics section also contained JoVE's 2000th video article, filmed in a synchrotron radiation facility, where Borisenko et al. showed how to determine the electronic structure of complex materials using angle-resolved photoemission spectroscopy.
In the JoVE General section, we published an article by Artioli et al. demonstrating the use of a portable gas analyzer to measure oxygen consumption during complex exercise - such as judo. By analyzing oxygen consumption and collecting blood for measuring plasma lactate concentration, this method can determine the relative contributions of different energy systems to specific aspects of complex exercise.
Finally, JoVE followed Dolhi et al. to a permanently ice-covered saline lake in Antarctica. There, scientists drilled through the ice to study single-celled microorganisms called protists that live in the harsh conditions of Antarctica.
This Year in Review was just a brief glimpse of a few of over 600 video articles that JoVE offered in 2012. Browse the JoVE archives to see thousands of other videos, and stay tuned for what's coming up this year in JoVE: The Journal of Visualized Experiments.

Here's a look at some of the milestones and highlights of the year 2012 in Journal of Visualized Experiments (JoVE).

2012: Un año en revisión

 
 
Here's a look at some of the milestones and highlights of the year 2012 in Journal of Visualized Experiments (JoVE).
At the start of 2012, JoVE ...

04 2012: Este mes en Jove

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08 2012: Este mes en Jove

2012: Un año en revisión