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  • STED image of peripheral section of HeLa cell nucleus

    Abstracts of the 7th European Super-Resolution User-Club Meeting

    The 7th Super-Resolution User Club Meeting was held in collaboration with Prof Pavel Hozák , at the Institute of Molecular Genetics of the ASCR in Prague. Keeping the event close to science is one of the founding principles of the event, allowing all participants to network, share and explore exciting new super-resolution and nanoscopy applications. Central to this are the scientific talks given during the meeting, with this cutting-edge microscopy technique as their central theme. A wide selection of topics were covered, prompting interesting discussions during the workshops.
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  • The Fundamentals and History of Fluorescence and Quantum Dots

    At some point in your research and science career, you will no doubt come across fluorescence microscopy. This ubiquitous technique has transformed the way in which microscopists can image, tag and trace anything from whole organisms to single proteins and beyond. In this article, we will examine what is meant by "fluorescence", the history and basic physics behind its definition, the discovery and application of Green Fluorescent Protein (GFP) and a look at the rapidly expanding field of fluorescent probes including Quantum Dots.
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  • Testing the Münch Hypothesis of Long Distance Phloem Transport in Plants

    Long distance transport in plants occurs in sieve tubes of the phloem. The pressure flow hypothesis introduced by Ernst Münch in 1930 describes a mechanism of osmotically generated pressure differentials that are supposed to drive the movement of sugars and other solutes in the phloem, but this hypothesis has long faced major challenges. The key issue is whether the conductance of sieve tubes, including sieve plate pores, is sufficient to allow pressure flow. We show that with increasing distance between source and sink, sieve tube conductivity and turgor increases dramatically in Ipomoea nil. Our results provide strong support for the Münch hypothesis, while providing new tools for the investigation of one of the least understood plant tissues.
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  • Chronic Inflammation Under the Microscope

    In the course of chronic inflammation certain body areas are recurrently inflamed. This goes along with many human diseases. With the help of widefield light microscopy, the underlying processes can be examined from a cellular level to whole organisms. This article presents several widefield microscopy applications such as immunofluorescence, live-cell imaging, histology, and ratiometric analysis to get insight into the development of chronic inflammation, the related diseases, and their treatment.
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  • Multispectral Phloem-Mobile Probes: Properties and Applications

    Using Arabidopsis (Arabidopsis thaliana) seedlings, we identified a range of small fluorescent probes that entered the translocation stream and were unloaded at the root tip. These probes had absorbance/emission maxima ranging from 367/454 to 546/576 nm and represent a versatile toolbox for studying phloem transport. Of the probes that we tested, naturally occurring fluorescent coumarin glucosides (esculin and fraxin) were phloem loaded and transported in oocytes by the sucrose transporter, AtSUC2. Arabidopsis plants in which AtSUC2 was replaced with barley (Hordeum vulgare) sucrose transporter (HvSUT1), which does not transport esculin in oocytes, failed to load esculin into the phloem.
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  • Abstracts of the 6th European Super-Resolution User-Club Meeting

    The 6th European Super-Resolution User Club Meeting was held in collaboration with Dr. Timo Zimmermann, CRG, and Dr. Pablo Loza-Alvarez, ICFO, Barcelona. According to the founding principle of the club of keeping close to science, both imaging facilities at the CRG and the ICFO opened their doors to the User Club members, allowing them to explore exciting super-resolution and and nanoscopy applications. The meeting agenda covered highly relevant talks around this year’s central theme “Core Facilities and Super-Resolution Microscopy”, as well as plenty of opportunities to network amongst super-resolution users from different European countries. Here we present the abstracts of the talks held during the meeting.
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  • Webinar: Introduction to Fluorescence Microscopy

    In this seminar we will provide an overview about the latest advances in fluorescence microscopy. You will learn how you can use widefield and confocal microscopes to help you understand life’s questions down to tiny details, at high speed and state-of-the-art image quality both in living and fixed samples.
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  • Measuring the 3D STED-PSF with a new Type of Fluorescent Beads

    A new type of fluorescent bead is presented by GATTAquant. These beads, called GATTA-Beads, are characterized by a small diameter (23 nm), high intensity and size uniformity. In combination with state-of the-art STED microscopes such as the Leica TCS SP8 STED 3X and high-end image restoration methods available in the Huygens Software, it is shown that these new beads can be used for accurate STED PSF characterization in 3D. Furthermore, it is shown that the measured 3D STED-PSF can be used to improve image restoration quality in combination with STED deconvolution methods available in the Huygens Software.
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  • Fluorescent Proteins Illuminate Cell Biology

    Green fluorescent protein (GFP) isolated from the jellyfish Aequorea victoria and GFP-like fluorescent proteins from other animals have had an important role in the technical innovations that have driven these advances. This poster provides a comprehensive user's guide to fluorescent proteins and sensors , their key properties and the cell biological questions to which they can be applied.
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  • STED Nanoscopy with Fluorescent Quantum Dots

    The widely popular class of quantum-dot molecular labels could so far not be utilized as standard fluorescent probes in STED (stimulated emission depletion) nanoscopy. This is because broad quantum-dot excitation spectra extend deeply into the spectral bands used for STED, thus compromising the transient fluorescence silencing required for attaining super-resolution.
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  • How to Prepare Your Specimen for Immunofluorescence Microscopy

    Immunofluorescence (IF) is a powerful method for visualizing intracellular processes, conditions and structures. IF preparations can be analyzed by various microscopy techniques (e.g. CLSM, Epifluorescence, TIRF, GSDIM), depending on the application or the researcher’s interest. Meanwhile, IF has become indispensable for a large number of research groups which have at least access to a simple fluorescence microscope.
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  • Quick Guide to STED Sample Preparation

    This document is intended as a quick reference guide for the most common questions regarding the preparation of samples for the Leica SP8 TCS STED 3X, by briefly explaining the theoretical basics required from samples for stimulated emission depletion. It provides information about the most common immuno-fluorescence labeling techniques, working mounting media, basic quality optimization procedures and experiment designs. It also contains a detailed list of reagents, antibodies and disposables frequently and successfully used in super-resolution STED microscopy. In summary, this guide is meant to present the necessary knowledge, including some tips and tricks, to users that are preparing their first super-resolution microscopy sample.
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  • Online Tool to Determine the Optimal Combination of Fluorescence Filter Cubes, Fluorophores and Light Sources

    To achieve optimal results in fluorescence microscopy, the light source, the fluorophores and the filter cubes have to match perfectly. A fluorescence microscope with a perfect fit of excitation and emission filter set is able to maximize the efficiency of excitation and emission of the fluorophores and thus provide crisp fluorescence images. The online tool Leica FluoScout™ helps users achieve excellent fluorescence imaging results by recommending the optimum filter cube and filter cube set for their choice of fluorophores.
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  • Handbook of Optical Filters for Fluorescence Microscopy

    Fluorescence microscopy and other light-based applications require optical filters that have demanding spectral and physical characteristics. Often, these characteristics are application-specific and an optic that might be appropriate and optimal for one is both inappropriate and sub-optimal for another.
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  • Webinar: Fluorescent Probes and Digital Imaging: Where We Are and Where We're Going

    The discovery of green fluorescent protein a half century ago heralded a new and explosive era in microscopy, forever changing the landscape for biology imaging. The ability to fuse a genetically encoded fluorescent probe to an almost-unlimited variety of proteins has enabled scientists to investigate signaling pathways and the movement of intracellular proteins in living cells with unprecedented detail, particularly when coupled with powerful widefield fluorescence and confocal microscopy techniques.
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  • Fluorescent Dyes

    A basic principle in fluorescence microscopy is the highly specific visualization of cellular components with the help of a fluorescing agent. This can be a fluorescing protein – for example GFP – genetically linked to the protein of interest. If cloning is impossible – for instance in histologic samples – it is required to use other techniques like immunofluorescence staining to visualize the protein of interest.
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