Le protocole texte complet de cette approche expérimentale est disponible en <a class="jove_content" href="http://www.mrw.interscience.wiley.com/emrw/9780471143031/cp/cpcb/article/cb0401/current/abstract ">Current Protocols in Cell Biology.</a>

The authors have nothing to disclose.

proper care and cleaning of the microscope

Garder le microscope optique propre est important pour l&#39;imagerie de haute qualité. La poussière, les empreintes digitales, l&#39;huile d&#39;immersion en excès, ou milieu de montage sur ou dans un microscope entraîne une réduction de contraste et de résolution. DIC est particulièrement sensible à la contamination et de rayures sur la surface des lentilles. Ce protocole détaille la procédure pour garder le microscope propre.

Watch this Scientific Journal Video about Proper Care and Cleaning of the Microscope at JoVE.com

Proper Care and Cleaning of the Microscope

Entretien et nettoyage du microscope

Keeping the microscope optics clean is important for high-quality imaging. Dust, fingerprints, excess immersion oil, or mounting medium on or in a ...

proper-care-and-cleaning-of-the-microscope

Research

JoVE Journal

Biology

43.1K vues.  University of Texas Health Science Center at San Antonio (UTHSCSA). Garder le microscope optique propre est important pour l'imagerie de haute qualité. La poussière, les empreintes digitales, l'huile d'immersion en excès, ou milieu de montage sur ou dans un microscope entraîne une réduction de contraste et de résolution. DIC est particulièrement sensible à la contamination et de rayures sur la surface des lentilles. Ce protocole détaille la procédure pour garder le microscope propre.

Vidéo: Proper Care and Cleaning of the Microscope

Major Components of the Light Microscope

The light microscope is a basic tool for the cell biologist, who should have a thorough understanding of how it works, how it should be aligned for different applications, and how it should be maintained as required to obtain maximum image-forming capacity and resolution. The components of the microscope are described in detail here.

The light microscope is a basic tool for the cell biologist, who should have a thorough understanding of how it works, how it should be aligned for different applications, and how it should be maintained as required to obtain maximum image-forming capacity and resolution. The components of the microscope are described in detail here.

Principales composantes d&#39;un microscope optique

The light microscope is a basic tool for the cell biologist, who should have a thorough understanding of how it works, how it should be aligned for ...

Recherche

Biologie

Assembly, Tuning and Use of an Apertureless Near Field Infrared Microscope for Protein Imaging

This paper aims to instruct the reader in the assembly and operation of an infrared near-field microscope for imaging beyond the diffraction limit.  The apertureless near-field microscope is a light scattering-type instrument that provides infrared spectra at circa 20 nm resolution. A complete list of components and a step-by-step protocol for use is provided.  Common errors in assembly and instrument tuning are discussed.  A representative data set that shows the secondary structure of an amyloid fibril is presented.  

The assembly of a nearfield infrared microscope for imaging protein aggregates is described.

Assemblée, Tuning et utilisation d&#39;un microscope en champ proche infrarouge pour l&#39;imagerie Apertureless protéines

This paper aims to instruct the reader in the assembly and operation of an infrared near-field microscope for imaging beyond the diffraction limit.  The ...

Imaging of Estrogen Receptor-&alpha; in Rat Pial Arterioles using a Digital Immunofluorescent Microscope

Many of estrogen's effects on vascular reactivity are mediated through interaction with estrogen receptors 1, 2, 3. Although two sub-types exist (estrogen receptor -&alpha; and &beta;),estrogen receptor-&alpha; has been identified in both the smooth muscle and in endothelial cells of pial arterial segments using fluorescent staining combined with confocal laser scanning microscopy 4. Furthermore, ER-&alpha; is located in the nuclei and in the cytoplasm of rat basilar arteries 5. The receptors are abundant and fluoresce brightly, but clear visualization of discrete groups of receptors is difficult likely due to the numbers located in many cell layers of pial vessel segments. Additionally, many reports using immunohistochemical techniques paired with confocal microscopy poorly detail the requirements critical for reproduction of experiments 6. Our purpose for this article is to describe a simple technique to optimize the staining and visualization of ER-&alpha; using cross-sectional slices of pial arterioles obtain from female rat brains. We first perfuse rats with Evans blue dye to easily identify surface pial arteries which we isolate under a dissecting microscope. Use of a cryostat to slice 8 &mu;m cross sections of the arteries allows us to obtain thin vessel sections so that different vessel planes are more clearly visualized. Cutting across the vessel rather than use of a small vessel segment has the advantage of easier viewing of the endothelial and smooth muscle layers. In addition, use of a digital immunofluorescent microscope with extended depth software produces clear images of ten to twelve different vessel planes and is less costly than use of a confocal laser scanning microscope.

Imaging of Estrogen Receptor-&amp;#945; in Rat Pial Arterioles using a Digital Immunofluorescent Microscope

The goal of this article is to demonstrate a method to optimize immunofluorescent detection of estrogen receptor-&#945; (ER&#945;) in rat pial arterial slices using a digital immunofluorescent microscope.

Imagerie des récepteurs d&#39;estrogènes α chez le rat artérioles Pial aide d&#39;un microscope numérique immunofluorescence

Many of estrogen's effects on vascular reactivity are mediated through interaction with estrogen receptors 1, 2, 3. Although two sub-types exist (estrogen ...

Regular Care and Maintenance of a Zebrafish (Danio rerio) Laboratory: An Introduction

This protocol describes regular care and maintenance of a zebrafish laboratory. Zebrafish are now gaining popularity in genetics, pharmacological and behavioural research. As a vertebrate, zebrafish share considerable genetic sequence similarity with humans and are being used as an animal model for various human disease conditions. The advantages of zebrafish in comparison to other common vertebrate models include high fecundity, low maintenance cost, transparent embryos, and rapid development. Due to the spur of interest in zebrafish research, the need to establish and maintain a productive zebrafish housing facility is also increasing. Although literature is available for the maintenance of a zebrafish laboratory, a concise video protocol is lacking. This video illustrates the protocol for regular housing, feeding, breeding and raising of zebrafish larvae. This process will help researchers to understand the natural behaviour and optimal conditions of zebrafish husbandry and hence troubleshoot experimental issues that originate from the fish husbandry conditions. This protocol will be of immense help to researchers planning to establish a zebrafish laboratory, and also to graduate students who are intending to use zebrafish as an animal model.

Regular Care and Maintenance of a Zebrafish Danio rerio Laboratory: An Introduction

This protocol outlines regular maintenance and care to maintain optimal conditions for zebrafish husbandry. The video illustrates the protocol for system maintenance, regular housing, feeding, breeding, and raising of zebrafish larvae.

Soins et entretien réguliers d&#39;un poisson zèbre (<em&gt; Danio rerio</em&gt;) Laboratoire: An Introduction

This protocol describes regular care and maintenance of a zebrafish laboratory. Zebrafish are now gaining popularity in genetics, pharmacological and ...

Culturing of Human Nasal Epithelial Cells at the Air Liquid Interface

In vitro models using human primary epithelial cells are essential in understanding key functions of the respiratory epithelium in the context of microbial infections or inhaled agents. Direct comparisons of cells obtained from diseased populations allow us to characterize different phenotypes and dissect the underlying mechanisms mediating changes in epithelial cell function. Culturing epithelial cells from the human tracheobronchial region has been well documented, but is limited by the availability of human lung tissue or invasiveness associated with obtaining the bronchial brushes biopsies. Nasal epithelial cells are obtained through much less invasive superficial nasal scrape biopsies and subjects can be biopsied multiple times with no significant side effects. Additionally, the nose is the entry point to the respiratory system and therefore one of the first sites to be exposed to any kind of air-borne stressor, such as microbial agents, pollutants, or allergens. 
Briefly, nasal epithelial cells obtained from human volunteers are expanded on coated tissue culture plates, and then transferred onto cell culture inserts. Upon reaching confluency, cells continue to be cultured at the air-liquid interface (ALI), for several weeks, which creates more physiologically relevant conditions. The ALI culture condition uses defined media leading to a differentiated epithelium that exhibits morphological and functional characteristics similar to the human nasal epithelium, with both ciliated and mucus producing cells. Tissue culture inserts with differentiated nasal epithelial cells can be manipulated in a variety of ways depending on the research questions (treatment with pharmacological agents, transduction with lentiviral vectors, exposure to gases, or infection with microbial agents) and analyzed for numerous different endpoints ranging from cellular and molecular pathways, functional changes, morphology, etc. 
In vitro models of differentiated human nasal epithelial cells will enable investigators to address novel and important research questions by using organotypic experimental models that largely mimic the nasal epithelium in vivo.

Nasal epithelial cells, obtained through superficial scrape biopsy of human volunteers, are expanded and transferred onto tissue culture inserts. Upon reaching confluency, cells are grown at air liquid interface, yielding cultures of ciliated and non-ciliated cells. Differentiated nasal epithelial cell cultures provide viable experimental models for studying the respiratory mucosa.

Culture de cellules humaines épithéliales nasales à l&#39;interface Air Liquide

In vitro models using human primary  epithelial cells are essential in understanding key functions of the respiratory  epithelium in the context of ...

In Vivo Study of Human Endothelial-Pericyte Interaction Using the Matrix Gel Plug Assay in Mouse

Angiogenesis is the process by which new blood vessels are formed from existing vessels. New vessel growth requires coordinated endothelial cell proliferation, migration, and alignment to form tubular structures followed by recruitment of pericytes to provide mural support and facilitate vessel maturation. Current in vitro cell culture approaches cannot fully reproduce the complex biological environment where endothelial cells and pericytes interact to produce functional vessels. We present a novel application of the in vivo matrix gel plug assay to study endothelial-pericyte interactions and formation of functional blood vessels using severe combined immune deficiency mutation (SCID) mice. Briefly, matrix gel is mixed with a solution containing endothelial cells with or without pericytes followed by injection into the back of anesthetized SCID mice. After 14 days, the matrix gel plugs are removed, fixed and sectioned for histological analysis. The length, number, size and extent of pericyte coverage of mature vessels (defined by the presence of red blood cells in the lumen) can be quantified and compared between experimental groups using commercial statistical platforms. Beyond its use as an angiogenesis assay, this matrix gel plug assay can be used to conduct genetic studies and as a platform for drug discovery. In conclusion, this protocol will allow researchers to complement available in vitro assays for the study of endothelial-pericyte interactions and their relevance to either systemic or pulmonary angiogenesis.

In Vivo Study of Human Endothelial-Pericyte Interaction Using the Matrix Gel Plug Assay in Mouse

We present a protocol to study human endothelial-pericyte interactions in mouse using a variation of the matrix gel plug angiogenesis assay.

Etude in vivo de Human Interaction Endothelial-péricytes Utilisation du Gel Matrice Plug - test chez la souris

Angiogenesis is the process by which new blood vessels are formed from existing vessels. New vessel growth requires coordinated endothelial cell ...

Extracellular Vesicle Uptake Assay via Confocal Microscope Imaging Analysis

There is a need for practical assays to visualize and quantify the cells' extracellular vesicle (EV) uptake. EV uptake plays a role in intercellular communication in various research fields; cancer biology, neuroscience, and drug delivery. Many EV uptake assays have been reported in the literature; however, there is a lack of practical, detailed experimental methodology. EV uptake can be assessed by fluorescently labeling EVs to detect their location within cells. Distinguishing between internalized EVs in cells and the superficial EVs on cells is difficult, yet critical, to accurately determine the EV uptake. Therefore, an assay that efficiently quantifies EV uptake through three-dimensional (3D) fluorescence confocal microscopy is proposed in this work. Fluorescently labeled EVs were prepared using a nano-filtration-based microfluidic device, visualized by 3D confocal microscopy, and then analyzed through advanced image-processing software. The protocol provides a robust methodology for analyzing EVs on a cellular level and a practical approach for efficient analysis.

Extracellular Vesicle Uptake Assay via Confocal Microscope Imaging Analysis

Extracellular vesicles (EVs) contribute to cellular biology and intercellular communications. There is a need for practical assays to visualize and quantify EVs uptake by the cells. The current protocol proposes the EV uptake assay by utilizing three-dimensional fluorescence imaging via confocal microscopy, following EV isolation by a nano-filtration-based microfluidic device.

Test d’absorption des vésicules extracellulaires par analyse d’imagerie au microscope confocal

There is a need for practical assays to visualize and quantify the cells' extracellular vesicle (EV) uptake. EV uptake plays a role in intercellular ...

Isolation and Analysis of Traceable and Functionalized Extracellular Vesicles from the Plasma and Solid Tissues

Circulating and tissue-resident extracellular vesicles (EVs) represent promising targets as novel theranostic biomarkers, and they emerge as important players in the maintenance of organismal homeostasis and the progression of a wide spectrum of diseases. While the current research focuses on the characterization of endogenous exosomes with the endosomal origin, microvesicles blebbing from the plasma membrane have gained increasing attention in health and sickness, which are featured by an abundance of surface molecules recapitulating the membrane signature of parent cells. Here, a reproducible procedure is presented based on differential centrifugation for extracting and characterizing EVs from the plasma and solid tissues, such as the bone. The protocol further describes subsequent profiling of surface antigens and protein cargos of EVs, which are thus traceable for their derivations and identified with components related to potential function. This method will be useful for correlative, functional, and mechanistic analysis of EVs in biological, physiological, and pathological studies.

The present protocol describes a method to extract extracellular vesicles from the peripheral blood and solid tissues with subsequent profiling of surface antigens and protein cargos.

Isolement et analyse de vésicules extracellulaires traçables et fonctionnalisées à partir du plasma et des tissus solides

Circulating and tissue-resident extracellular vesicles (EVs) represent promising targets as novel theranostic biomarkers, and they emerge as important ...

Revêtement de grilles TEM avec une monocouche de graphène

Fabrication of Monolayer Graphene-Coated Grids for Cryoelectron Microscopy

Cryogenic electron microscopy (cryoEM) has emerged as a powerful technique for probing the atomic structure of macromolecular complexes. Sample preparation for cryoEM requires preserving specimens in a thin layer of vitreous ice, typically suspended within the holes of a fenestrated support film. However, all commonly used sample preparation approaches for cryoEM studies expose the specimen to the air-water interface, introducing a strong hydrophobic effect on the specimen that often results in denaturation, aggregation, and complex dissociation. Further, preferred hydrophobic interactions between regions of the specimen and the air-water interface impact the orientations adopted by the macromolecules, resulting in 3D reconstructions with anisotropic directional resolution. 
Adsorption of cryoEM specimens to a monolayer of graphene has been shown to help mitigate interactions with the air-water interface while minimizing the introduction of background noise. Graphene supports also offer the benefit of substantially lowering the required concentration of proteins required for cryoEM imaging. Despite the advantages of these supports, graphene-coated grids are not widely used by the cryoEM community due to the prohibitive expense of commercial options and the challenges associated with large-scale in-house production. This paper describes an efficient method for preparing batches of cryoEM grids that have nearly full coverage of monolayer graphene.

Pleins feux sur l’auteur : Améliorer la résolution de CryoEM à l’aide de grilles recouvertes de graphène 

Here, we describe a protocol for applying a single monolayer of graphene to electron microscopy grids and how to prepare them for use in cryoEM structure determination.