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Chao W.,Massachusetts Eye and Ear Infirmary | Kolski-Andreaco A.,JoVE Content Production
Journal of Visualized Experiments | Year: 2016

Here’s a look at what’s coming up in the June 2016 issue of JoVE: The Journal of Visualized Experiments. In JoVE Chemistry, just in time for blueberry season, we feature a method for predicting the constituents of blueberries while keeping them intact. Bai et al. use near-infrared spectroscopy to obtain spectra of individual blueberries, then use high-performance liquid chromatography (HPLC) to measure their actual contents. They build models that use the near-infrared spectra to predict the levels of sugar, the organic acids that impart tartness, and the anthocyanins that have antioxidant properties. This method aids the selection and distribution of only the most delicious blueberries with guaranteed qualities. JoVE Engineering includes a test protocol that simulates on-field impacts of football helmets to help reduce the risks of head injuries. Current performance standards for football helmet certification don’t require the faceguard to be attached during impact tests; however, attaching a faceguard dramatically changes the helmet’s mechanical properties. Therefore, Rush et al. propose a modified test that includes the faceguard. They also test two new helmet impact locations. This method provides more robust helmet safety standards that will drive safer helmet designs. In JoVE Developmental Biology, human pluripotent stem cells (hPSCs) can differentiate into all three developmental germ layers. However, in vitro differentiation of hPSCs tends to be a disorganized process. This month, Sahni et al. describe stencil micropatterning-a method that can spatially control stem cell microenvironments and organize their differentiation fates. This elegant method provides a valuable experimental model for tissue organization and patterning in embryonic development. In JoVE Environment, soil plasticity is a concept inspired by the craft of pottery. It refers to the clay-like behavior of certain soils at particular water content levels. The plastic limit of soil is an important parameter in geotechnology, but traditional assessment methods are highly subjective. Thus, Moreno-Maroto and Alonso-Azcárate present an alternative method based on objective measures. This method allows the plastic limit of soil to be obtained with clear and objective criteria. You’ve just had a sneak peek of the June 2016 issue of JoVE. Visit the website to see the full-length articles, plus many more, in JoVE: The Journal of Visualized Experiments. © 2016 Journal of Visualized Experiments.


Chao W.,Massachusetts Eye and Ear Infirmary | Kolski-Andreaco A.,JoVE Content Production
Journal of Visualized Experiments | Year: 2016

In January 2015, JoVE Developmental Biology became the newest addition to the JoVE family, and featured a live-imaging protocol for visualizing the developing Drosophila eye. In February, JoVE Medicine showed state-of-the-art cranial ultrasound imaging in neonates. Advances in this technique have improved its diagnostic value, allowing timely therapeutic intervention. In March, JoVE Environment featured dendroecology, the science of using tree rings to study ecological effects of specific environmental factors. In April, JoVE Biology examined a mode of bacterial motility called swarming with a two-phase swarm assay. that can be used to study various aspects of bacterial growth. In May, JoVE Chemistry described the self-assembly of single-stranded DNA tiles into complex 2D shapes. This demonstrated the principles of DNA tiling as an approach for making programmable nanostructures. June 2015 marked the release of JoVE's 100th issue, and in JoVE Behavior, we featured protocols for assessing cognition, including a method of quantifying learning in young infants by tracking leg movements. In July, JoVE Medicine presented a method for measuring halitosis in dogs by taking breath samples, and performing gas chromatography. This assay could be used in trials of dog food formulated to fight bad breath in our canine companions. In August, JoVE Bioengineering contained a protocol for bioengineering kidney tissues. Kidneys are decellularized by perfusion, and repopulated with human renal cells, This promising technology can lead to kidney grafts made from a patient's own cells. In September, JoVE Environment examined herbicide resistance, which threatens commercial crop production. An excised leaf assay determines the rates of herbicide metabolism, which is useful for studying the metabolic basis of resistance. In October, JoVE Neuroscience featured a method for interfacing 3D neuronal cultures to micro-electrode arrays. The complex 3D assemblies closely approximate in vivo neural networks. November's edition of JoVE Behavior showcased the natural human ability to acquire new motor skills, which is central in a structured rehabilitation program for amputees as they learn how to use multifunctional prosthetics. In December, JoVE Immunology & Infection prepared us for the impending flu season with an easy protocol for sampling influenza in pigs. Because swine are important hosts for flu viruses, this method helps to monitor virus evolution and currently circulating strains. This Year in Review was just a sampling of more than 900 video-articles that JoVE published in 2015. Browse the JoVE archives for thousands of other videos, and come back each week to see brand-new material in JoVE: The Journal of Visualized Experiments. © 2016 Journal of Visualized Experiments.


Chao W.,Massachusetts Eye and Ear Infirmary | Kolski-Andreaco A.,JoVE Content Production
Journal of Visualized Experiments | Year: 2016

Here’s a look at what’s coming up in the February 2016 issue of JoVE: The Journal of Visualized Experiments. In JoVE Developmental Biology, the transparent, rapidly developing zebrafish embryo is ideal for visualizing developmental processes. When cells of interest are labeled with fluorescent photoconvertible proteins, they allow precise tracking of defined structures-highlighting specific cells while leaving other transgenic cells in the dark. Beretta et al. have established the photoswitchable monomeric orange (PSmOrange) system for zebrafish. This protein’s orange-to-red spectrum allows it to visible in existing transgenic lines expressing green fluorescent protein (GFP). Microinjection of nuclear-targeted PSmOrange mRNA labels all cell nuclei with orange/red fluorescence, and targeted photoconversion switches its emission spectrum to far red. The quantum efficiency and stability of PSmOrange makes it a superb cell-tracking tool for living zebrafish during embryonic development and disease. In JoVE Chemistry, few materials have found as many uses in so many diverse fields as gold nanoparticles. Their applications range from biological sensors to radio frequency-based cancer treatments. Gold nanoparticles are valued for their unique structural, optical and electronic properties. These special attributes caught the interest of Oliver Smithies, who won the Nobel Prize in Physiology or Medicine in 2007. This month, he and his colleagues describe a simple method for producing highly stable oligomeric clusters of gold nanoparticles, and present models that can predict particle size with great accuracy. In JoVE Engineering, we look at the principles of positron emission tomography (PET), a non-invasive technique for imaging the body's inner tissues and organs. Montaño-Zetina and Villalobos-Mora present a guide for constructing a simple, homemade PET system for fully characterizing its basic working principles. This prototype demonstrates the primary functions of PET, and serves as an elegant model for teaching its principles to the academic public. In JoVE Medicine, it is well established that the bone marrow microenvironment provides a haven for hematopoietic diseases. This month, Slone et al. use cell types from the bone marrow niche in an in vitro co-culture model. This supports the generation of a subpopulation of chemoresistant tumor cells. These calls can be used to investigate the underlying pathways of tumor development and to test novel therapeutic strategies. You’ve just had a sneak peek of the February 2016 issue of JoVE. Visit the website to see the full-length articles, plus many more, in JoVE: The Journal of Visualized Experiments. © 2016 Journal of Visualized Experiments.


Chao W.,Massachusetts Eye and Ear Infirmary | Kolski-Andreaco A.,JoVE Content Production
Journal of Visualized Experiments | Year: 2016

Here’s a look at what’s coming up in the May 2016 issue of JoVE: The Journal of Visualized Experiments. In JoVE Environment, we examine the cheetah-one of Africa’s most iconic animals, but also an endangered species. Monitoring the cheetah population is challenging to conservation efforts, especially since current tagging techniques can be invasive, expensive, and unreliable. Jewell et al. present a new approach that uses image classification of footprints to identify individual cheetahs. The footprint identification algorithms can distinguish cheetahs from other species (due to unique species-specific anatomy) and predict individual cheetah identity with high accuracy. This is the first robust footprint identification technique described for cheetahs and is applicable at any site where footprints are found. In JoVE Medicine, the lens of the eye owes much of its focusing power on its ability to change shape so it can form clear images on the retina. In humans, age-related stiffening of the lens leads to a reduced ability to accommodate or focus on close objects. Like human lenses, mouse lenses become stiffer with age, so Cheng et al. use them as a model for understanding lens pathologies. They present a protocol for determining mouse lens stiffness, applying sequentially increasing compressive loads onto the lens. This method is precise, simple, and reproducible, and can be scaled up to mechanically test lenses from larger animals. In JoVE Behavior, we feature an experimental analysis of children’s capacity to tell lies. In police and forensic interviews, kids have been known to purposely omit information, and even make false denials or accusations. In this study, Wyman et al. have children witness a staged theft, and then ask them to either falsely deny the theft, falsely accuse someone else of the theft, or tell the truth. They measure various aspects of both true and false accounts, and examine the social and developmental factors that influence a child’s testimony. These methods can help improve the understanding of testimonies from children. In JoVE Engineering, scientists are developing alternatives for conventional silicon solar cells, because their production is expensive and consumes a lot of energy. This month, Cherrington et al. present methods for the large-scale production of dye-sensitized solar cells (DSSCs) using inkjet printing. DSSCs have a fundamentally different working principle than silicon solar cells, and their production is less damaging to the environment. With continued development, this inkjet-printing process may be a low-cost, environmentally friendly alternative to conventional solar cells. You've just had a sneak peek of the May 2016 issue of JoVE. Visit the website to see the full-length articles, plus many more, in JoVE: The Journal of Visualized Experiments. © 2016 Journal of Visualized Experiments.


Chao W.,Massachusetts Eye and Ear Infirmary | Kolski-Andreaco A.,JoVE Content Production
Journal of Visualized Experiments | Year: 2016

Here's a look at what's coming up in the March 2016 issue of JoVE: The Journal of Visualized Experiments. In JoVE Biology, RNA interference (RNAi) is a natural mechanism of gene silencing that occurs via double-stranded RNA (dsRNA), which targets homologous DNA for degradation. This phenomenon allows researchers to selectively silence genes in many eukaryotes-making RNAi an extremely valuable tool for uncovering gene function. However, in the mosquito Anopheles gambiae, a major vector for malaria, RNAi has limited ability to target genes during developmental stages. This month, Regna et al. present an RNAi protocol using direct injection during pupal development. After the pupae complete development, their adult phenotypes confirm the gene knockdown. This method expands the arsenal of genomic tools for vector insect research. In JoVE Developmental Biology, induced pluripotent stem cells (iPSCs) have been generated from many cell types, and are valuable models for human development and disease. iPSCs are also valued for their potential applications in regenerative medicine. This month, Ulm et al. demonstrate methods for sampling nasal epithelial mucosa from children, then culturing the samples to obtain nasal epithelial cells (NECs), which are reprogrammed into iPSCs. NECs are of particular interest because they're the primary cells infected with respiratory viruses, and are readily accessible during clinical visits. Therefore, this protocol facilitates patient-specific research in airway epithelial biology. In JoVE Environment, filters are important tools in atmospheric aerosols research. These sampled filters collect ambient particles, such as endotoxins and biological aerosols, for analysis. In this issue, Lang-Yona et al. use air-sampled filters for two complementary analyses of atmospheric biological particles: endotoxin and DNA. Specifically, they study endotoxin components of gram-negative bacterial cell walls, known collectively as lipopolysaccharide (LPS). In parallel, they perform a genomic evaluation of the sample's bacterial content. This method can produce highly accurate and reliable analyses for biological aerosol research. In JoVE Medicine, researchers are finding new ways to treat wounds with a patient's own tissues, This month, Purpura et al. describe a new method of creating autologous micrografts. When cultured on collagen sponges, these micro-grafts become bio-complexes ready to use in the treatment of skin lesions. These biocomplexes were applied in a patient, who showed good healing after 30 days. This new regenerative approach shows promise as an efficient, one-step treatment of acute and chronic lesions. You've just had a sneak peek of the March 2016 issue of JoVE. Visit the website to see the full-length articles, plus many more, in JoVE: The Journal of Visualized Experiments. © 2016 Journal of Visualized Experiments.


Chao W.,Massachusetts Eye and Ear Infirmary | Kolski-Andreaco A.,JoVE Content Production
Journal of Visualized Experiments | Year: 2015

Here's a look at what's coming up in the December 2015 issue of JoVE: The Journal of Visualized Experiments. In JoVE Immunology & Infection, we know that the peak of flu season is on its way-and because pigs are important hosts for the influenza A virus, it is critical to monitor virus evolution in swine populations to get a snapshot of current circulating strains. Nasal swabs are a gold-standard technique for taking diagnostic samples from live pigs, but it requires restraining the pigs. Nolting et al. present an alternative sampling method using nasal wipes, which involves rubbing a piece of fabric across the snout of the pig with minimal to no restraint of the animal. The nasal wipe procedure is simple to perform, and virus detection and isolation rates are adequate to make it a viable and low-stress sampling method for flu in pigs. In JoVE Chemistry, DNA nanorobots are hollow hexagonal nanodevices that open in response to specific stimuli to present the cargo sequestered inside. This month, Amir et al. describe a nanorobot fabrication protocol that uses the DNA origami technique. This involves mixing short single-stranded DNA staples with long, circular, single-stranded DNA scaffolds. In a standard thermocycler, the staples anneal to the scaffolds, thus driving the folding of the nanorobot. After the folding reaction is complete, agarose gel electrophoresis (AGE) is used to visualize and estimate the purity of the DNA nanorobots. Finally, nanorobot fabrication is verified by transmission electron microscopy (TEM). This procedure allows for the construction of complex 2D/3D nano-architecture. In JoVE Environment, crude oil is one of the most valuable natural resources because it is the raw material for many fuels and chemical products. Accurate analysis of crude oil, especially the content of highly toxic hydrogen sulfide (H2S), is essential for developing and implementing safety measures in the event of a release or spill. Heshka and Hager present a multidimensional gas chromatography method for analyzing dissolved hydrogen sulfide in crude oil samples. As far as we know, this is the only method that can accurately measure dissolved hydrogen sulfide in heavy crudes, without the use of sub-ambient cooling. In JoVE Behavior, Frisbee et al. present one of the most useful models for studying the pathophysiology of depression in rodents. This protocol uses a variety of mild stressors, and after a period of exposure to unpredictable chronic mild stress, rodents develop behaviours and cardiovascular alterations that are comparable to the symptoms of clinical depression. This approach allows for detailed studies of the pathological mechanisms of chronic stress, and can be used to test new therapies and interventions for chronic stress-induced depression. You've just had a sneak peek of the December 2015 issue of JoVE. Visit the website to see the full-length articles, plus many more, in JoVE: The Journal of Visualized Experiments © 2015 Journal of Visualized Experiments.


Chao W.,Massachusetts Eye and Ear Infirmary | Kolski-Andreaco A.,JoVE Content Production
Journal of Visualized Experiments | Year: 2015

Here's a look at what's coming up in the February 2015 issue of JoVE: The Journal of Visualized Experiments. In JoVE Environment we have a method for tracing outbreaks of food poisoning to insects. Everyone knows that insects can deposit disease-causing organisms on our food. Not surprisingly, insects are important vectors of foodborne illnesses caused by pathogens like Salmonella, E. coli, and Listeria. However, it's hard to link an outbreak of food poisoning to a specific type of insect. This is because individual insects are not usually collected aseptically in environmental sampling programs. Therefore, Pava-Ripoll et al. from the U.S. Food and Drug Administration take microbial samples from individual flies under aseptic conditions and use PCR to detect specific pathogens. PCR-positive samples are then confirmed by plating on selective or differential media and through commercial biochemical assays. Using this method, public health officials can better determine how insects contribute to foodborne outbreaks. JoVE's Clinical & Translational Medicine section features cranial ultrasound-an indispensable technique for safely imaging the neonatal brain. Ecury-Goossen et al. demonstrate optimal settings that provide better imaging quality, and color Doppler techniques for visualizing intracerebral vessels. They also demonstrate how alternate acoustic windows can improve detection of brain injuries. These advances in cranial ultrasound have improved its diagnostic value-allowing timely therapeutic intervention. In JoVE Behavior we have two articles that deal with attention. One involves attentional set shifting, or the ability to direct attention to informative cues and away from irrelevant ones. Heisler et al. perform this test in mice that have been trained to dig in pots for a food reward. The test cues are different digging materials and different scents. The mice learn to pay attention to a single relevant cue to find their food. The neural circuits behind attentional set shifting are highly conserved between rodents and humans; therefore, this model can be used to preclinically evaluate cognitive deficits and potential therapies. In another article in JoVE Behavior, Yung et al. perform two well-known attention tests in an online platform. The multiple object tracking (MOT) task studies the motion-based tracking of multiple objects by the visual system, and the Useful Field of View (UFOV) Task assesses attention and processing speed of visual stimuli from a brief glance. Our authors collected data from over 1,700 participants in a Massive Online Open Course. The results were highly consistent with controlled laboratory-based measures of the same tests, showing the usefulness of behavior studies done entirely online. You've just had a sneak peek of the February 2015 issue of JoVE. Visit the website to see the full-length articles, plus many more, in JoVE: The Journal of Visualized Experiments. © JoVE 2006-2015. All Rights Reserved.


Chao W.,Massachusetts Eye and Ear Infirmary | Kolski-Andreaco A.,JoVE Content Production
Journal of Visualized Experiments | Year: 2016

This month we are pleased to introduce three new sections of the JoVE family: Genetics, Biochemistry, and Cancer Research. JoVE Genetics contains methodologies for exploring all aspects of genes and heredity-from human genetics to model organisms, epigenetics to evolutionary genetics, and gene editing to gene therapy. This section features a method for genotyping pufferfish species by liquid chromatography/mass spectrometry, described by Miyaguchi. This technique can aid in the appropriate identification and differentiation of toxic species, which is not only important for public health but also for forensics and investigations of food fraud. Also in JoVE Genetics, Yu et al. report methods for genetically engineering the unconventional yeast Yarrowia lipolytica with improved gene deletion efficiency. The engineered Y. lipolytica strains have potential applications in biofuel and biochemical production. JoVE Biochemistry comprises methods that advance our understanding of biomolecule structure and function, as well as their interactions and transformations during biological processes. This month, Gunning et al. present a method of meat authentication using multiple reaction monitoring (MRM) mass spectrometry, which identifies peptides and gives relative quantitation for detecting adulterant species in meat mixtures. This method is sensitive enough to detect 1% horsemeat in beef products. Also in JoVE Biochemistry, Head and Liu describe a method for identifying small molecule-binding proteins using photoaffinity labeling. The target proteins are bound and covalently labeled within the live cellular environment, which helps preserve native protein structure and binding conditions. JoVE Cancer Research encompasses a broad range of techniques used to advance the understanding and treatment of cancer. This includes methodologies for studying carcinogenesis, developing innovative diagnostics and therapeutics, and uncovering the mechanisms of drug resistance. This month in JoVE Cancer Research, Ansari et al. report a method of targeted cell isolation via glass surface functionalization. This method can identify biomarkers of resistance or susceptibility to anti-angiogenic therapies. Also in this section, Domogauer et al. present a mixed cell culture model that mimics the tumor microenvironment. With this model, the intercellular communication within the tumor microenvironment can be studied under various conditions. © 2016 Journal of Visualized Experiments.


Chao W.,Massachusetts Eye and Ear Infirmary | Kolski-Andreaco A.,JoVE Content Production
Journal of Visualized Experiments | Year: 2016

Here's a look at what's coming up in the July 2016 issue of JoVE: The Journal of Visualized Experiments. In JoVE Neuroscience, gustatory perception - or taste - is an important factor for pollinating insects and the flowers that they feed from. Most studies have used restrained honeybees to study gustatory responses towards nutrients and toxins. This month, Ma et al. present a new behavioral assay that uses freely moving bumblebees to measure how different compounds influence their feeding behavior. This assay will be useful to pollination biologists, toxicologists, and neuroethologists studying the bumblebee's taste system. In JoVE Environment, trace metal measurements in natural waters are often inaccurate due to inadequate sampling and analytical techniques. In fact, using improved techniques, researchers are finding that true concentrations of dissolved trace metals may be orders of magnitude lower than previously thought. So Jiann et al. present a protocol for clean sampling and trace metal analysis of river and estuary waters. They present techniques for reducing contamination throughout all phases of trace metal analysis. The improved data quality allows accurate assessment of trace metals and their relationships to environmental parameters. In JoVE Engineering, Janus colloids are special nanoparticles that have multiple chemical, physical, and structural properties - making them attractive tools for biomedical applications. Campbell et al. present a method to prepare catalytically active Janus colloids that "swim" in fluids, and determine their 3D motion using fluorescence microscopy. With this method, 3D trajectories are obtained for the swimming colloid, which allows accurate measurement of swimming velocity and other physical phenomena. In JoVE Behavior, vision problems can have a major impact on development. But in young children or those with intellectual disabilities, it is often difficult quantitatively assess visual problems, which limits accurate diagnostics. To overcome these problems, Kooiker et al. describe a method for quantifying visual information processing. A remote eye tracker measures eye movements in response to different visual stimuli - providing valuable information for vision assessment and rehabilitation. You've just had a sneak peek of the July 2016 issue of JoVE. Visit the website to see the full-length articles, plus many more, in JoVE: The Journal of Visualized Experiments. © 2016 Journal of Visualized Experiments.


Chamberlain N.,JoVE Content Production | Kolski-Andreaco A.,JoVE Content Production
Journal of Visualized Experiments | Year: 2016

Here’s a look at what’s coming up in the October 2016 issue of JoVE: The Journal of Visualized Experiments. In Immunology and Infection, we showcase a series of four videos detailing safety and logistical procedures for working in an Animal Biosafety Level 4, or (A)BSL-4, laboratory. The first of this group, filmed at the NIH Integrated Research Facility at Fort Detrick, demonstrates the safe entry and exit procedures for work inside an (A)BSL-4 suit laboratory suite. Inhalation studies of high-consequence pathogens can simulate natural aerosol transmission, or allow researchers to investigate outcomes of intentional pathogenic aerosol releases. In the second of this series, the authors walk through the safe operation of aerobiology chambers for maximum containment level pathogens, such as the Ebola virus. The challenge of carrying out medical imaging in a high biosafety environment is the focus of the third of these releases. Here, our Authors detail how to prepare animals infected with high-consequence pathogens for noninvasive medical imaging, whilst ensuring that the equipment remains easily accessed and free from contamination. In the final video of this miniseries, we take an in-depth look at the extra precautions and procedures involved in performing viral assays in a Class II biosafety cabinet in a BSL-4 environment. As a whole, these four releases are a valuable library for researchers handling challenging and potentially harmful biological materials. Woody plants and secondary tree stems are key habitats, as well as being of great cultural and commercial importance. Understanding stem growth and wood formation is therefore an important topic for tree production, conservation, and preservation. In JoVE Genetics this month, Spokevicius et al (our Authors) describe a method to create transgenic somatic tissue sectors directly in the living secondary stem of woody plants. This versatile method can facilitate rapid functional characterization of genes of interest, be utilized in a range of tree species, and test multiple genes and promoters at a high throughput level. Arguably one of the most recognizable paintings of all time, the Mona Lisa is famous for the subject’s elusive smile and indefinable expression. In JoVE Behavior, Soranzo and Newbury (our Authors) demonstrate how a similar visual illusion-dubbed the "uncatchable smile" because of it’s tendency to disappear as the observer tries to catch it-was discovered in La Bella Principessa, also by Da Vinci. Using a combination of methods including interobservation, psychophysical experiments, and structured interviews, the authors reveal that the ambiguity in La Bella Principessa’s expression is attributed to a visual illusion at the mouth of the subject similar to that observed in the Mona Lisa. You’ve just had a sneak peek of the October 2016 issue of JoVE. Visit the website to see the full-length articles, plus many more, in JoVE: The Journal of Visualized Experiments. © 2016 Journal of Visualized Experiments.

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