Here, we demonstrate fabrication of collagen-based, tissue constructs containing skeletal myoblasts. These 3-D engineered constructs may be used to replace or repair tissues in vivo. For our purposes, we have designed these as an atrioventricular electrical conduit for the repair of complete heart block[1].
Here, we describe a cardiac surgical procedure to implant engineered tissue in the atrioventricular (AV)-groove of an adult Lewis rat.
Molecular shuttles consisting of functionalized microtubules gliding on surface-adhered kinesin motor proteins can serve as a nanoscale transport system. Here, the assembly of a typical shuttle system is described.
The Vermicelli and Capellini Handling Tests of forepaw dexterity take advantage of the natural inclination of rodents to manipulate food items using skillful forepaw and digit movements. Animals are videotaped while handling short strands of uncooked dry pasta. Slow motion video playback allows for the quantification of forepaw adjustments.
This video protocol demonstrates the neurosphere assay method to generate and expand neural stem cells from the adult mouse periventricular region, and provides technical insights to ensure one can achieve reproducible neurosphere cultures.
This video protocol demonstrates the application of the neurosphere assay for the isolation and expansion of neural stem cells from the ganglionic eminences of embryonic day 14-mouse brain.
In this article, we describe the identification of the adeno-associated virus serotype 3 (AAV3) as the most efficient vector for targeting human liver cancer cells.
This video protocol demonstrates how to discriminate and enumerate bona fide neural stem cells in a mixed population of neural precursor cells using the neural colony-forming cell assay.
Cell-mediated lymphocytotoxicity (CML) assays can be used to test autoreactive responses and study mechanisms of cell death in vitro. However, using live-cell confocal microscopic imaging techniques with fluorescent dyes, the type and kinetics of cell death as well as the pathways utilized can be studied in greater detail.
A procedure for liquid-based culturing and dispensing of C. elegans strains expressing fluorescent reporter proteins is described that does not require expensive sorting equipment. This approach can be applied to numerous inducible C. elegans genes for drug discovery or biosensing of contaminants.
The intraluminal middle cerebral artery occlusion (MCAO) model is the most frequent used model among experimental ischemic stroke models. Here we will demonstrate the entire model in detail with the guide of Laser Doppler flowmetry, and its representative results.
The electrode-tissue interface of neural recording electrodes can be characterized with electrical impedance spectroscopy (EIS) and cyclic voltammetry (CV). Application of voltage biasing changes the electrochemical properties of the electrode-tissue interface and can improve recording capability. Voltage biasing, EIS, CV, and neural recordings are complementary.
This video protocol demonstrates the isolation and expansion of stem like cells from surgically resected human glioblastoma mutliforme (GBM) tumor tissue using the neurosphere assay culture method.
This video protocol demonstrates a novel method for the generation and subsequent purification of neuronal progenitor cells from a renewable source of neural stem cells (NSCs) based on their physical (size and internal granularity) and fluorescent properties using flow cytometry technology.
Reactive oxygen species level is elevated when cells encounter stress conditions. Here we show the example of 3'-3' diaminobenzidine staining as well as cysTMT labeling and mass spectrometry to profile the redox proteome in Pseudomonas syringae treated tomato leaves.
This video protocol demonstrates the application of the fluorescent dye carboxyfluorescein succinimidyl ester (CFSE) for the identification and separation of different sub-populations of cells in human glioblastoma based on frequency of cell division.
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.
Several animal models of cerebral ischemia have been developed to simulate the human condition of stroke. This protocol describes the endothelin-1 (ET-1) induced middle cerebral artery occlusion (MCAO) model for ischemic stroke in rats. In addition, important considerations, advantages, and shortcomings of this model are discussed.
This article describes a method for visualizing rat cerebral arteries through a cranial window using temporal craniectomy in order to view proximal portions of the middle cerebral artery (Figure 1). This versatile method can be combined with various techniques of drug delivery to measure cerebral artery reactivity in vivo.
Here we present a histological method for capturing, labeling, optically clearing, and imaging the intact brain tissue interface around chronically implanted microdevices in rodent brain tissue. Results from the techniques comprising this method are useful for understanding the impact of various penetrating brain-implants on their surrounding tissue.
We describe here the procedures for the extraction and purification of mRNA and metabolites from Drosophila heads. We are applying these techniques to better understand the cellular perturbations underlying neuronal degeneration. These methodologies can be easily scaled and adapted for other "omic" projects.
There has been renewed interest in developing polymer valves. Here, the objectives are to demonstrate the feasibility of modifying a commercial pulse duplicator to accommodate tri-leaflet geometries and to define a protocol to present polymer valve hydrodynamic data in comparison to native and prosthetic valve data collected under near-identical conditions.
Three new behavioral tests (forelimb step-alternation, postural instability test, pasta handling test) for evaluating forelimb function after cervical spinal cord injury in rodents are described.
Traditional procedures for the isolation of soluble type 1 collagen (COL1) require about 10 days from start to finish because of lengthy buffer incubations and laborious resuspensions of fibrils. Here, we describe a means to purify COL1 from small dermal biopsies in less than 3 hr.
A protocol involving integrated concentration, enrichment, and end-point colorimetric detection of foodborne pathogens in large volumes of agricultural water is presented here. Water is filtered through Modified Moore Swabs (MMS), enriched with selective or non-selective media, and detection is performed using paper-based analytical devices (µPAD) imbedded with bacterial-indicative colorimetric substrates.
Minimally invasive thumb-sized pterional craniotomy for aneurysm clipping has afforded our patients with a shorter hospital stay at a lower cost compared to the national average.
A method for rapid isolation of mitochondria from mammalian tissue biopsies is described. Rat liver or skeletal muscle preparations were homogenized with a commercial tissue dissociator and mitochondria were isolated by differential filtration through nylon mesh filters. Mitochondrial isolation time is <30 min compared to 60 - 100 min using alternative methods.
Here we demonstrate a technique for widespread neuronal transduction by intraventricular injection of adeno-associated virus into the neonatal mouse brain. This method provides a rapid and easy way to attain lifelong expression of virally-delivered transgenes.
Muscle sensory neurons are involved in proprioceptor signaling and also report on metabolic state and injury related events. We describe an adult mouse in vitro muscle-nerve preparation for studies on stretch-activated muscle afferents.
Malaria transmitting mosquitoes have a number of epidemiologically important characteristics that can only be detected using molecular techniques. Utilizing a MALDI-TOF based SNP genotyping platform, we developed an assay for simultaneously detecting multiple key traits (species, insecticide resistance, parasite infection and host choice) of malaria vectors.
This article describes the methodology for administering short periods of intermittent hypoxia to postnatal day 1-8 mouse or rat pups. This approach effectively elicits a robust tissue level “priming effect” on cultured neural progenitor cells that are harvested within 30 min of hypoxia exposure.
Circulating tumor cells (CTCs) have been shown to play an important role in tumor metastasis. Here, a method for the isolation and propagation of CTCs from the whole blood of a syngeneic mouse tumor model of hepatocellular carcinoma (HCC) metastasis is described.
Here we describe the detailed procedure of intestinal ischemia-reperfusion in mice which results in reproducible injury without mortality to encourage the standardization of this technique across the field. This model of intestinal ischemia-reperfusion injury can be utilized to study the cellular and molecular mechanisms of injury and regeneration.
Preventing colonization of bird nest boxes by invasive Africanized honey bees is important for conservation efforts of nest-site limited birds. We provide an integrated pest management approach to "push" bees away from nest boxes with a repellant insecticide, permethrin, and "pull" them toward pheromone baited swarm traps.
Concussion presents the most common type of traumatic brain injury. Therefore, a repetitive concussive animal model, which replicates the important features of an injury in patients, may provide a means to study concussion in a rigorous, controlled, and efficient manner.
A protocol to screen for endocrine activity in organic extracts of water samples, including treated wastewater effluent and surface (receiving) water, was adapted using commercially available division-arrested ("freeze and thaw") in vitro transactivation bioassays.
Insecticide evaluations are often targeted against adult insects, rather than immature stages. Here, we present a protocol for evaluating insecticides against bed bug eggs with a comparison to the first nymphal bed bug stage. These protocols could be adjusted for other insects to evaluate insecticide efficacy in non-adult life stages.
Here, we describe a protocol for the application of a novel, slow-release ClO2 product that reduces spoilage and extends the shelf life of fresh fruit. The slow-release ClO2 product was added to standard commercial grape tomato packaging and tested against Escherichia coli and Alternaria alternata.
Nutrients present in particulate form can contribute significantly to the overall loads in agricultural drainage waters. This study describes a novel method to capture flow-weighted water and suspended particulates from farm canal drainage over the entire duration of the drainage event.
The current protocol describes a method by which users can maintain viability of acute hippocampal and cortical slice preparations during the collection of magnetic resonance microscopy data.
Here, we present a protocol to image human pancreas sections in three dimensions (3D) using optimized passive clearing methods. This manuscript demonstrates these procedures for passive optical clearing followed by multiple immunofluorescence staining to identify key elements of the autonomic and sensory neural networks innervating human islets.
Current multiplexed diagnostics to detect Zika, chikungunya, and dengue viruses require complex sample preparation and expensive instrumentation, and are difficult to use in low resource environments. We show a diagnostic that uses isothermal amplification with target-specific strand displaceable probes to detect and differentiate these viruses with high sensitivity and specificity.
This protocol describes a method of preparing enriched stomatal guard cells that is useful for physiological and other biological studies.
In this protocol, we describe a micropipette method to directly apply a controlled force to the nucleus in a living cell. This assay allows interrogation of nuclear mechanical properties in the living, adherent cell.
This paper details the surgical protocol for minimally invasive endoscopic intracerebral hemorrhage evacuation using the SCUBA technique.
This protocol describes a method to record the descending electrical activity of the Drosophila melanogaster central nervous system to enable the cost-efficient and convenient testing of pharmacological agents, genetic mutations of neural proteins, and/or the role of unexplored physiological pathways.
Facial expressions are a mode of visual communication produced by mimetic muscles. Here, we present protocols for the novel techniques of reverse dissection and DiceCT to fully visualize and assess mimetic muscles. These combined techniques can examine both morphological and physiological aspects of mimetic musculature to determine functional aspects.
This protocol provides the necessary steps to establish and evaluate neonatal sepsis in 7-day-old mice.
Here, we present a protocol for collecting the floral fragrance volatiles from blooming flowers, using a non-destructive sampling procedure.
The goal of this protocol is to illustrate how to use mouse neonatal cardiomyocytes as a model system to examine how various factors can alter oxygen consumption in the heart.
Here we present a protocol for the construction of a cell culture chamber designed to expose cells to various types of electrical stimulation, and its use in treating mesenchymal stem cells to enhance osteogenic differentiation.
When administering transcranial direct current stimulation (tDCS), reproducible electrode preparation and placement are vital for a tolerated and effective session. The purpose of this article is to demonstrate updated modern setup procedures for the administration of tDCS and related transcranial electrical stimulation techniques, such as transcranial alternating current stimulation (tACS).
This protocol describes both in vivo and ex vivo methods to fully visualize and characterize hyaloid vessels, a model of vascular regression in mouse eyes, using optical coherence tomography and fundus fluorescein angiography for the live imaging and ex vivo isolation and subsequent flat mount of hyaloid for quantitative analysis.
A CRISPR/sgRNA library has been applied to interrogating protein-coding genes.However, the feasibility of a sgRNA library to uncover the function of a CTCF boundary in gene regulation remains unexplored. Here, we describe a HOX loci specific sgRNA library to elucidate the function of CTCF boundaries in HOX loci.
The goal of this protocol is to manipulate the color patterns of jumping spiders and other very small arthropods with paint in order to study questions related to sexual selection, sexual cannibalism, predation, aposematism, or any other field of animal coloration.
Presented here is a protocol to determine the number of thrips and minute pirate bug predators in crops over multiple dates in field experiments. Also illustrated is how to determine the efficacy of management tactics against thrips and evaluate the benefits of predation by minute pirate bugs.
We describe a surgical protocol to consistently induce robust descending thoracic aortic aneurysms in mice. The procedure involves left thoracotomy, thoracic aorta exposure, and placement of a sponge soaked in porcine pancreatic elastase on the aortic wall.
This novel model creates robust infrarenal abdominal aortic aneurysms in swine using a combination of balloon angioplasty, elastase/collagenase perfusion, topical elastase application, and oral compound β-aminopropionitrile administration, which interferes with collagen cross-linking.
Here, we present protocols for 1) the laboratory captive propagation of the federally endangered Miami blue butterfly (Cyclargus thomasi bethunebakeri), and 2) assessing basic life history information such as immature development time and number of larval stadia. Both methods can be adapted for use with other ex situ conservation programs.
We present an optimized tandem mass tag (TMT) labeling protocol that includes detailed information for each of the following steps: protein extraction, quantification, precipitation, digestion, labeling, submission to a proteomics facility, and data analyses.
The goal of this protocol is to quantify binding of the eukaryotic pathogen human norovirus to bacteria. After performing an initial virus-bacterium attachment assay, flow cytometry is used to detect virally-bound bacteria within the population.
We present here a protocol of a blast wave model for rodents to investigate neurobiological and pathophysiological effects of mild to moderate traumatic brain injury. We established a gas-driven, bench-top setup equipped with pressure sensors allowing for reliable and reproducible generation of blast-induced mild to moderate traumatic brain injury.
A method is described to create organoids using patient-derived xenografts (PDX) for in vitro screening, resulting in matched pairs of in vivo/in vitro models. PDX tumors were harvested/processed into small pieces mechanically or enzymatically, followed by the Clevers’ method to grow tumor organoids that were passaged, cryopreserved and characterized against the original PDX.
We developed a method to detect Phytophthora capsici zoospores in water sources using a filter paper DNA extraction method coupled with a loop-mediated isothermal amplification (LAMP) assay that can be analyzed in the field or in the lab.
Many characteristics of insect eusociality rely on within-colony communication and division of labor. Genetic manipulation of key regulatory genes in ant embryos via microinjection and CRISPR-mediated mutagenesis provides insights into the nature of altruistic behavior in eusocial insects.
This study presents the application of live pancreatic tissue slices to the study of islet physiology and islet-immune cell interactions.
Here, a low-cost, accessible protocol is described to evaluate cold shock recovery of butterflies under ambient environmental conditions.
The sterile insect technique (SIT) is used to control specific, medically important mosquito populations that may be resistant to chemical controls. Here, we describe a method of mass rearing and preparation of sterile male mosquitoes for release in an operational SIT program targeting the Aedes aegypti mosquito.
The glioma stem cells (GSCs) are a small fraction of cancer cells which play essential roles in tumor initiation, angiogenesis, and drug resistance in glioblastoma (GBM), the most prevalent and devastating primary brain tumor. The presence of GSCs makes the GBM very refractory to most of individual targeted agents, so high-throughput screening methods are required to identify potential effective combination therapeutics. The protocol describes a simple workflow to enable rapid screening for potential combination therapy with synergistic interaction. The general steps of this workflow consist of establishing luciferase-tagged GSCs, preparing matrigel coated plates, combination drug screening, analyzing, and validating the results.
Described here is a DNA extraction protocol using magnetic beads to produce high quality DNA extractions from mosquitoes. These extractions are suitable for a downstream next-generation sequencing approach.
Salivary glands have been proposed as a tissue target site for gene therapy, especially in the area of vaccination by gene transfer. We demonstrate gene delivery in a non-human primate model utilizing retrograde parotid infusion.
The protocol describes the development of a standardized, repeatable, preclinical model of exertional heat stroke (EHS) in mice free from adverse external stimuli such as electric shock. The model provides a platform for mechanistic, preventative, and therapeutic studies.
This paper presents a detailed stepwise protocol on how to utilize an integrated multi-functional and user-programmable system that enables automatic multi-channel imaging and mechanobiological analysis to elucidate the mechano-sensitivity of Yes-associated protein (YAP).
The following protocol describes the development and optimization of a high-throughput workflow for worm culturing, fluorescence imaging, and automated image processing to quantify polyglutamine aggregates as an assessment of changes in proteostasis.
This is a protocol for the surgical implantation and operation of a wirelessly powered interface for peripheral nerves. We demonstrate the utility of this approach with examples from nerve stimulators placed on either the rat sciatic or phrenic nerve.
The protocol describes a straightforward method of resectioning an intact mouse liver for metabolic studies through portal vein perfusion.
Managing Fusarium wilt of watermelon requires knowledge of the pathogen races present. Here, we describe the root-dip, infested kernel seeding, and modified tray-dip inoculation methods to demonstrate their efficacy in race-typing of the pathogenic fungus Fusarium oxysporum f. sp niveum (Fon).
Here, we present a straightforward protocol for noninvasive genetic sampling of butterfly populations based on the field collection of residual egg debris. It can be used to confirm species identity and quantify genetic variation. This protocol can be easily adapted to broader groups for community science involvement.
The present protocol provides a detailed procedure for inducing subarachnoid hemorrhage in mice via autologous blood injection to the anterior circulation and measuring delayed cerebral vasospasm by vascular gel casting.
This protocol details the surgical steps of murine common iliac arteriovenous fistula creation. We developed this model to study hemodialysis access-related limb pathophysiology.
The article describes an embryo rescue protocol for the regeneration of immature embryos derived from the interspecific hybridization of Cucurbita pepo and Cucurbita moschata. The protocol can be easily replicated and will be an important resource for squash breeding programs.
This protocol illustrates an in vitro endothelial cell transcytosis assay as a model to evaluate inner blood-retinal barrier permeability by measuring the ability of human retinal microvascular endothelial cells to transport horseradish peroxidase across cells in caveolae-mediated transcellular transport processes.
This study presents a new protocol to directly apply mechanical force on the cell nucleus through magnetic microbeads delivered into the cytoplasm and to conduct simultaneous live-cell fluorescent imaging.
A novel sample preparation method is demonstrated for the analysis of agar-based, bacterial macrocolonies via matrix-assisted laser desorption/ionization imaging mass spectrometry.
Novel Methodological Perspectives In The Study Of Mosquito Biology
A novel and minimally invasive protocol is presented to evaluate the synergistic impact of fuel utilization and circadian rhythms on aging individuals, utilizing peripheral blood mononuclear cells.
This manuscript outlines the steps for performing a micro-ultrasound-guided transperineal prostate biopsy under local anesthesia.
Increasing the detection of immature tephritid fruit flies in the field can trigger timely efforts to eliminate populations of these destructive pests. Detecting late instar larvae is faster and more accurate when mushing host fruit in a bag and passing the pulp through a series of sieves than hand cutting and visual inspection.
We present CorrelationCalculator and Filigree, two tools for data-driven network construction and analysis of metabolomics data. CorrelationCalculator supports building a single interaction network of metabolites based on expression data, while Filigree allows building a differential network, followed by network clustering and enrichment analysis.
This manuscript details an optimized inoculation protocol that uses detached maize leaf sheaths for reproducible cytological, physiological, and molecular studies of maize interactions with fungal plant pathogens. The leaf sheaths facilitate real-time observation of cellular interactions between the living plant and fungus in unfixed tissues.
Organoids have become valuable tools for disease modeling. The extracellular matrix (ECM) guides cell fate during organoid generation, and using a system that resembles the native tissue can improve model accuracy. This study compares the generation of induced pluripotent stem cells-derived human intestinal organoids in animal-derived ECM and xeno-free hydrogels.
Adeno-associated virus is produced in suspension cell culture and purified by double iodixanol density gradient centrifugation. Steps are included to increase total virus yield, decrease the risk of virus precipitation, and further concentrate the final virus product. Expected final titers reach 1012 viral particles/mL and are suitable for pre-clinical in vivo use.
This murine model combines a septic insult with hindlimb muscle disuse to recapitulate the bedridden feature of the typical septic patient. The model represents a significant departure from previous models to study muscle dysfunction in sepsis and is a reproducible approach to addressing therapeutic strategies to treat this condition.
We demonstrate a tested method for safely handling field-collected bees. This method allows swift manipulation, identification, genetic sampling, and confirmation of plant-insect interactions via pollen collected while sampling. Easily adaptable, this approach offers a cost-effective, non-lethal means to study rare insect groups.
SOBRE A JoVE
Copyright © 2024 MyJoVE Corporation. Todos os direitos reservados