journal
MENU ▼
Read by QxMD icon Read
search

Journal of Visualized Experiments: JoVE

journal
https://www.readbyqxmd.com/read/28930993/confocal-imaging-of-neuropeptide-y-phluorin-a-technique-to-visualize-insulin-granule-exocytosis-in-intact-murine-and-human-islets
#1
Madina Makhmutova, Tao Liang, Herbert Gaisano, Alejandro Caicedo, Joana Almaça
Insulin secretion plays a central role in glucose homeostasis under normal physiological conditions as well as in disease. Current approaches to study insulin granule exocytosis either use electrophysiology or microscopy coupled to the expression of fluorescent reporters. However most of these techniques have been optimized for clonal cell lines or require dissociating pancreatic islets. In contrast, the method presented here allows for real time visualization of insulin granule exocytosis in intact pancreatic islets...
September 13, 2017: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/28930984/high-fat-diet-feeding-and-high-throughput-triacylglyceride-assay-in-drosophila-melanogaster
#2
Soda Balla Diop, Ryan T Birse, Rolf Bodmer
Heart disease is the number one cause of human death worldwide. Numerous studies have shown strong connections between obesity and cardiac malfunction in humans, but more tools and research efforts are needed to better elucidate the mechanisms involved. For over a century, the genetically highly tractable model of Drosophila has been instrumental in the discovery of key genes and molecular pathways that proved to be highly conserved across species. Many biological processes and disease mechanisms are functionally conserved in the fly, such as development (e...
September 13, 2017: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/28930982/development-of-a-human-preclinical-model-of-osteoclastogenesis-from-peripheral-blood-monocytes-co-cultured-with-breast-cancer-cell-lines
#3
Laura Mercatali, Chiara Spadazzi, Giacomo Miserocchi, Chiara Liverani, Alessandro De Vita, Alberto Bongiovanni, Federica Recine, Dino Amadori, Toni Ibrahim
The crosstalk between tumor cells and bone cells in the bone microenvironment is crucial to understanding the mechanism of bone metastasis formation. We developed an in vitro fully human preclinical model of a co-culture of breast cancer cells and monocytes undergoing differentiation towards osteoclasts. We optimized a model of osteoclastogenesis starting from a sample of peripheral blood collected from healthy donors. Peripheral blood mononuclear cells (PBMCs) were first separated by density gradient centrifugation, seeded at a high density and induced to differentiate by adding two growth factors (GFs): receptor activator of nuclear factor-κB ligand (RANKL) and macrophage colony-stimulating factor (MCSF)...
September 13, 2017: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/28930977/fourier-based-diffraction-analysis-of-live-caenorhabditis-elegans
#4
Jenny Magnes, Harold M Hastings, Kathleen M Raley-Susman, Clara Alivisatos, Adam Warner, Miranda Hulsey-Vincent
This manuscript describes how to classify nematodes using temporal far-field diffraction signatures. A single C. elegans is suspended in a water column inside an optical cuvette. A 632 nm continuous wave HeNe laser is directed through the cuvette using front surface mirrors. A significant distance of at least 20-30 cm traveled after the light passes through the cuvette ensures a useful far-field (Fraunhofer) diffraction pattern. The diffraction pattern changes in real time as the nematode swims within the laser beam...
September 13, 2017: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/28931001/an-automated-rapid-iterative-negative-geotaxis-assay-for-analyzing-adult-climbing-behavior-in-a-drosophila-model-of-neurodegeneration
#5
Wenze Cao, Li Song, Jingjing Cheng, Na Yi, Luyi Cai, Fu-de Huang, Margaret Ho
Neurodegenerative diseases are frequently associated with a progressive loss of movement ability, reduced life span, and age-dependent neurodegeneration. To understand the mechanism of these cellular events, and their causal relationships with each other, Drosophila melanogaster, with its sophisticated genetic tools and diverse behavioral features, are used as disease models for assessing neurodegenerative phenotypes. Here we describe a high-throughput method to analyze Drosophila adult negative geotaxis behavior, as an indication for possible motor defects associated with neurodegeneration...
September 12, 2017: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/28930999/measuring-and-mapping-patterns-of-soil-erosion-and-deposition-related-to-soil-carbonate-concentrations-under-agricultural-management
#6
Robert H Erskine, Lucretia A Sherrod, Timothy R Green
Spatial patterns of soil erosion and deposition can be inferred from differences in ground elevation mapped at appropriate time increments. Such changes in elevation are related to changes in near-surface soil carbonate (CaCO3) profiles. The objective is to describe a simple conceptual model and detailed protocol for repeatable field and laboratory measurements of these quantities. Here, accurate elevation is measured using a ground-based differential global positioning system (GPS); other data acquisition methods could be applied to the same basic method...
September 12, 2017: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/28930997/using-in-vivo-and-tissue-and-cell-explant-approaches-to-study-the-morphogenesis-and-pathogenesis-of-the-embryonic-and-perinatal-aorta
#7
Ashish Misra, Zhonghui Feng, Jiasheng Zhang, Zhi-Yin Lou, Daniel M Greif
The aorta is the largest artery in the body. The aortic wall is composed of an inner layer of endothelial cells, a middle layer of alternating elastic lamellae and smooth muscle cells (SMCs), and an outer layer of fibroblasts and extracellular matrix. In contrast to the widespread study of pathological models (e.g., atherosclerosis) in the adult aorta, much less is known about the embryonic and perinatal aorta. Here, we focus on SMCs and provide protocols for the analysis of the morphogenesis and pathogenesis of embryonic and perinatal aortic SMCs in normal development and disease...
September 12, 2017: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/28930994/measuring-in-vivo-changes-in-extracellular-neurotransmitters-during-naturally-rewarding-behaviors-in-female-syrian-hamsters
#8
Kelsey M Moore, Brett T Himmler, Benjamin A Teplitzky, Matthew D Johnson, Robert L Meisel
The ability to measure neurotransmitter release on a rapid time scale allows patterns of neurotransmission to be linked to specific behaviors or manipulations; a powerful tool in elucidating underlying mechanisms and circuitry. While the technique of microdialysis has been used for decades to measure nearly any analyte of interest in the brain, this technique is limited in temporal resolution. Alternatively, fast scan cyclic voltammetry is both temporally precise and extremely sensitive; however, because this technically difficult method relies on the electroactivity of the analyte of interest, the possibility to detect nonelectroactive substances (e...
September 12, 2017: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/28930998/in-vitro-ovule-cultivation-for-live-cell-imaging-of-zygote-polarization-and-embryo-patterning-in-arabidopsis-thaliana
#9
Daisuke Kurihara, Yusuke Kimata, Tetsuya Higashiyama, Minako Ueda
In most flowering plants, the zygote and embryo are hidden deep in the mother tissue, and thus it has long been a mystery of how they develop dynamically; for example, how the zygote polarizes to establish the body axis and how the embryo specifies various cell fates during organ formation. This manuscript describes an in vitro ovule culture method to perform live-cell imaging of developing zygotes and embryos of Arabidopsis thaliana. The optimized cultivation medium allows zygotes or early embryos to grow into fertile plants...
September 11, 2017: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/28930995/stereotactic-atlas-guided-laser-capture-microdissection-of-brain-regions-affected-by-traumatic-injury
#10
Harris A Weisz, Deborah R Boone, Stacy L Sell, Helen L Hellmich
The ability to isolate specific brain regions of interest can be impeded in tissue disassociation techniques that do not preserve their spatial distribution. Such techniques also potentially skew gene expression analysis because the process itself can alter expression patterns in individual cells. Here we describe a laser capture microdissection (LCM) method to selectively collect specific brain regions affected by traumatic brain injury (TBI) by using a modified Nissl (cresyl violet) staining protocol and the guidance of a rat brain atlas...
September 11, 2017: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/28930973/intracortical-inhibition-within-the-primary-motor-cortex-can-be-modulated-by-changing-the-focus-of-attention
#11
Yves-Alain Kuhn, Martin Keller, Jan Ruffieux, Wolfgang Taube
It is well recognized that an external focus (EF) compared with an internal focus (IF) of attention improves motor learning and performance. Studies have indicated benefits in accuracy, balance, force production, jumping performance, movement speed, oxygen consumption, and fatiguing task. Although behavioral outcomes of using an EF strategy are well explored, the underlying neural mechanisms remain unknown. A recent TMS study compared the activity of the primary motor cortex (M1) between an EF and an IF. More precisely, this study showed that, when adopting an EF, the activity of intracortical inhibitory circuits is enhanced...
September 11, 2017: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/28930971/determination-of-the-optimal-chromosomal-location-s-for-a-dna-element-in-escherichia-coli-using-a-novel-transposon-mediated-approach
#12
Jakob Frimodt-Møller, Godefroid Charbon, Karen A Krogfelt, Anders Løbner-Olesen
The optimal chromosomal position(s) of a given DNA element was/were determined by transposon-mediated random insertion followed by fitness selection. In bacteria, the impact of the genetic context on the function of a genetic element can be difficult to assess. Several mechanisms, including topological effects, transcriptional interference from neighboring genes, and/or replication-associated gene dosage, may affect the function of a given genetic element. Here, we describe a method that permits the random integration of a DNA element into the chromosome of Escherichia coli and select the most favorable locations using a simple growth competition experiment...
September 11, 2017: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/28930975/streamlined-single-cell-tcr-isolation-and-generation-of-retroviral-vectors-for-in-vitro-and-in-vivo-expression-of-human-tcrs
#13
Maran L Sprouse, Gabriele Blahnik, Thomas Lee, Natalie Tully, Pinaki Benarjee, Eddie A James, Maria J Redondo, Matthew L Bettini, Maria Bettini
Although, several methods for sequencing of paired T cell receptor (TCR) alpha and beta chains from single T cells have been developed, none so far have been conducive to downstream in vivo functional analysis of TCR heterodimers. We have developed an improved protocol based on a two-step multiplex-nested PCR, which results in a PCR product that spans entire variable regions of a human TCR alpha and beta chains. By identifying unique restriction sites and incorporating them into the PCR primers, we have made the PCR product compatible with direct sub-cloning into the template retroviral vector...
September 10, 2017: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/28930974/procedure-and-key-optimization-strategies-for-an-automated-capillary-electrophoretic-based-immunoassay-method
#14
Gail M Nelson, Jenna M Guynn, Brian N Chorley
New technologies that utilize capillary-based immunoassays promise faster and more quantitative protein assessment compared to traditional immunoassays. However, similar to other antibody-based protein assays, optimization of capillary-based immunoassay parameters, such as protein concentration, antibody dilution, and exposure time is an important prerequisite to the generation of meaningful and reliable data. Measurements must fall within the linear range of the assay where changes in signal are directly proportional to changes in lysate concentration...
September 10, 2017: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/28930972/study-of-protein-protein-interactions-in-autophagy-research
#15
Secil Erbil-Bilir, Nur M Kocaturk, Melih Yayli, Devrim Gozuacik
Protein-protein interactions are important for understanding cellular signaling cascades and identifying novel pathway components and protein dynamics. The majority of cellular activities require physical interactions between proteins. To analyze and map these interactions, various experimental techniques as well as bioinformatics tools were developed. Autophagy is a cellular recycling mechanism that allows the cells to cope with different stressors, including nutrient deprivation, chemicals, and hypoxia. In order to better understand autophagy-related signaling events and to discover novel factors that regulate protein complexes in autophagy, we performed protein-protein interaction screens...
September 9, 2017: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/28930992/a-cell-culture-model-of-resistance-arteries
#16
Lauren A Biwer, Christophe Lechauve, Sheri Vanhoose, Mitchell J Weiss, Brant E Isakson
The myoendothelial junction (MEJ), a unique signaling microdomain in small diameter resistance arteries, exhibits localization of specific proteins and signaling processes that can control vascular tone and blood pressure. As it is a projection from either the endothelial or smooth muscle cell, and due to its small size (on average, an area of ~1 µm(2)), the MEJ is difficult to study in isolation. However, we have developed a cell culture model called the vascular cell co-culture (VCCC) that allows for in vitro MEJ formation, endothelial cell polarization, and dissection of signaling proteins and processes in the vascular wall of resistance arteries...
September 8, 2017: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/28930989/demonstration-of-a-hyperlens-integrated-microscope-and-super-resolution-imaging
#17
Dasol Lee, Minkyung Kim, Sunae So, Inki Kim, Gwanho Yoon, Kyunghoon Kim, Junsuk Rho
The use of super-resolution imaging to overcome the diffraction limit of conventional microscopy has attracted the interest of researchers in biology and nanotechnology. Although near-field scanning microscopy and superlenses have improved the resolution in the near-field region, far-field imaging in real-time remains a significant challenge. Recently, the hyperlens, which magnifies and converts evanescent waves into propagating waves, has emerged as a novel approach to far-field imaging. Here, we report the fabrication of a spherical hyperlens composed of alternating silver (Ag) and titanium oxide (TiO2) thin layers...
September 8, 2017: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/28930986/low-pressure-vapor-assisted-solution-process-for-tunable-band-gap-pinhole-free-methylammonium-lead-halide-perovskite-films
#18
Carolin M Sutter-Fella, Yanbo Li, Nicola Cefarin, Aya Buckley, Quynh Phuong Ngo, Ali Javey, Ian D Sharp, Francesca M Toma
Organo-lead halide perovskites have recently attracted great interest for potential applications in thin-film photovoltaics and optoelectronics. Herein, we present a protocol for the fabrication of this material via the low-pressure vapor assisted solution process (LP-VASP) method, which yields ~19% power conversion efficiency in planar heterojunction perovskite solar cells. First, we report the synthesis of methylammonium iodide (CH3NH3I) and methylammonium bromide (CH3NH3Br) from methylamine and the corresponding halide acid (HI or HBr)...
September 8, 2017: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/28930981/generation-of-prostate-cancer-cell-models-of-resistance-to-the-anti-mitotic-agent-docetaxel
#19
Lisa Mohr, Marc Carceles-Cordon, Jungreem Woo, Carlos Cordon-Cardo, Josep Domingo-Domenech, Veronica Rodriguez-Bravo
Microtubule targeting agents (MTAs) are a mainstay in the treatment of a wide range of tumors. However, acquired resistance to chemotherapeutic drugs is a common mechanism of disease progression and a prognostic-determinant feature of malignant tumors. In prostate cancer (PC), resistance to MTAs such as the taxane Docetaxel dictates treatment failure as well as progression towards lethal stages of disease that are defined by a poor prognosis and high mortality rates. Though studied for decades, the array of mechanisms contributing to acquired resistance are not completely understood, and thus pose a significant limitation to the development of new therapeutic strategies that could benefit patients in these advanced stages of disease...
September 8, 2017: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/28930991/using-an-adapted-microfluidic-olfactory-chip-for-the-imaging-of-neuronal-activity-in-response-to-pheromones-in-male-c-elegans-head-neurons
#20
Douglas K Reilly, Daniel E Lawler, Dirk R Albrecht, Jagan Srinivasan
The use of calcium indicators has greatly enhanced our understanding of neural dynamics and regulation. The nematode Caenorhabditis elegans, with its completely mapped nervous system and transparent anatomy, presents an ideal model for understanding real-time neural dynamics using calcium indicators. In combination with microfluidic technologies and experimental designs, calcium-imaging studies using these indicators are performed in both free-moving and trapped animals. However, most previous studies utilizing trapping devices, such as the olfactory chip described in Chronis et al...
September 7, 2017: Journal of Visualized Experiments: JoVE
journal
journal
41706
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"