1
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Nagumo T, Sakaue M, Wakatsuki M, Inoue Y, Mukai S, Yamochi T, Takaki T. A novel technique of STEM observation of TEM section using LVSEM and application of pathological diagnosis of renal biopsy. Microscopy (Oxf) 2023; 72:49-55. [PMID: 36269105 DOI: 10.1093/jmicro/dfac055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 10/17/2022] [Accepted: 10/19/2022] [Indexed: 11/15/2022] Open
Abstract
The usefulness of the transmission electron microscope (TEM) for pathological diagnosis is apparent. However, high operating costs and other disadvantages have limited the ability to maintain and operate a TEM. In recent years, a general-purpose benchtop low-vacuum scanning electron microscope (LVSEM), which is inexpensive and easy to operate, has been developed and is expected to be applied in electron microscopic pathological diagnosis. To date, we have previously observed TEM ultrathin sections of Immunoglobulin A (IgA) nephropathy with a benchtop LVSEM using an ultra variable-pressure detector (UVD) and a newly developed holder for observing scanning transmission electron microscope (STEM) images (UVD-STEM holder) and compared the images with those obtained with typical TEM observations. We reported the results in the 53rd Annual Meeting of the Japanese Society for Clinical Molecular Morphology and the 64th Symposium of The Japanese Society of Microscopy and discussed the validity of the methods in the pathological diagnosis of IgA nephropathy and other renal diseases. As a result, we demonstrated the potential for pathological diagnosis using benchtop LVSEM. In this study, we similarly examined typical kidney diseases such as membranous nephropathy, lupus nephritis and amyloidosis. We could obtain sufficient data for the pathological diagnosis of IgA nephropathy, membranous nephropathy and lupus nephritis. However, it is difficult to detect amyloid fibres that are characteristic of amyloidosis. The development of this method is expected to expand the possibilities for pathological diagnosis using electron microscopy, including its application to other diseases.
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Affiliation(s)
- Tasuku Nagumo
- Department of Pathology, Showa University School of Medicine, 1-5-8, Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
| | - Mari Sakaue
- Hitachi High-Tech Corporation, 882, Ichige, Hitachinaka-shi, Ibaraki 312-8504, Japan
| | - Mone Wakatsuki
- Department of Anesthesia, Showa University Graduate School of Dentistry, 2-1-1, Kitasenzoku, Ota-ku, Tokyo 145-8515, Japan
| | - Yuriko Inoue
- Department of Pathology, Showa University School of Medicine, 1-5-8, Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan.,Department of Anatomy, Showa University School of Medicine, Tokyo 142-8555, Japan
| | - Shumpei Mukai
- Digestive Disease Center, Showa University Northern Yokohama Hospital, 35-1, Chigasakityuou, Tuzuki-ku, Yokohama-shi, Kanagawa 224-8503, Japan
| | - Toshiko Yamochi
- Department of Pathology, Showa University School of Medicine, 1-5-8, Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan
| | - Takashi Takaki
- Department of Pathology, Showa University School of Medicine, 1-5-8, Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan.,Center for Electron Microscopy, Showa University, Tokyo 142-8555, Japan
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2
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Bernardini A, Trovatelli M, Kłosowski MM, Pederzani M, Zani DD, Brizzola S, Porter A, Rodriguez Y Baena F, Dini D. Reconstruction of ovine axonal cytoarchitecture enables more accurate models of brain biomechanics. Commun Biol 2022; 5:1101. [PMID: 36253409 PMCID: PMC9576772 DOI: 10.1038/s42003-022-04052-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 09/29/2022] [Indexed: 12/03/2022] Open
Abstract
There is an increased need and focus to understand how local brain microstructure affects the transport of drug molecules directly administered to the brain tissue, for example in convection-enhanced delivery procedures. This study reports a systematic attempt to characterize the cytoarchitecture of commissural, long association and projection fibres, namely the corpus callosum, the fornix and the corona radiata, with the specific aim to map different regions of the tissue and provide essential information for the development of accurate models of brain biomechanics. Ovine samples are imaged using scanning electron microscopy combined with focused ion beam milling to generate 3D volume reconstructions of the tissue at subcellular spatial resolution. Focus is placed on the characteristic cytological feature of the white matter: the axons and their alignment in the tissue. For each tract, a 3D reconstruction of relatively large volumes, including a significant number of axons, is performed and outer axonal ellipticity, outer axonal cross-sectional area and their relative perimeter are measured. The study of well-resolved microstructural features provides useful insight into the fibrous organization of the tissue, whose micromechanical behaviour is that of a composite material presenting elliptical tortuous tubular axonal structures embedded in the extra-cellular matrix. Drug flow can be captured through microstructurally-based models using 3D volumes, either reconstructed directly from images or generated in silico using parameters extracted from the database of images, leading to a workflow to enable physically-accurate simulations of drug delivery to the targeted tissue. Imaging and reconstruction of sheep brain axonal cytoarchitecture provides insight for brain biomechanics models that simulate drug delivery and other biological processes governed by interstitial fluid flow and transport.
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Affiliation(s)
- Andrea Bernardini
- Department of Mechanical Engineering, Imperial College London, London, SW7 2AZ, UK.
| | - Marco Trovatelli
- Faculty of Veterinary Medicine, Università degli Studi di Milano Statale, 26900, Lodi, Italy
| | | | - Matteo Pederzani
- Department of Electronics, Information and Bioengineering, Politecnico di Milano, 20133, Milan, Italy
| | - Davide Danilo Zani
- Faculty of Veterinary Medicine, Università degli Studi di Milano Statale, 26900, Lodi, Italy
| | - Stefano Brizzola
- Faculty of Veterinary Medicine, Università degli Studi di Milano Statale, 26900, Lodi, Italy
| | - Alexandra Porter
- Department of Materials, Imperial College London, London, SW7 2AZ, UK
| | | | - Daniele Dini
- Department of Mechanical Engineering, Imperial College London, London, SW7 2AZ, UK.
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3
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Zhang Y, Ackels T, Pacureanu A, Zdora MC, Bonnin A, Schaefer AT, Bosch C. Sample Preparation and Warping Accuracy for Correlative Multimodal Imaging in the Mouse Olfactory Bulb Using 2-Photon, Synchrotron X-Ray and Volume Electron Microscopy. Front Cell Dev Biol 2022; 10:880696. [PMID: 35756997 PMCID: PMC9213878 DOI: 10.3389/fcell.2022.880696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Accepted: 04/22/2022] [Indexed: 11/23/2022] Open
Abstract
Integrating physiology with structural insights of the same neuronal circuit provides a unique approach to understanding how the mammalian brain computes information. However, combining the techniques that provide both streams of data represents an experimental challenge. When studying glomerular column circuits in the mouse olfactory bulb, this approach involves e.g., recording the neuronal activity with in vivo 2-photon (2P) calcium imaging, retrieving the circuit structure with synchrotron X-ray computed tomography with propagation-based phase contrast (SXRT) and/or serial block-face scanning electron microscopy (SBEM) and correlating these datasets. Sample preparation and dataset correlation are two key bottlenecks in this correlative workflow. Here, we first quantify the occurrence of different artefacts when staining tissue slices with heavy metals to generate X-ray or electron contrast. We report improvements in the staining procedure, ultimately achieving perfect staining in ∼67% of the 0.6 mm thick olfactory bulb slices that were previously imaged in vivo with 2P. Secondly, we characterise the accuracy of the spatial correlation between functional and structural datasets. We demonstrate that direct, single-cell precise correlation between in vivo 2P and SXRT tissue volumes is possible and as reliable as correlating between 2P and SBEM. Altogether, these results pave the way for experiments that require retrieving physiology, circuit structure and synaptic signatures in targeted regions. These correlative function-structure studies will bring a more complete understanding of mammalian olfactory processing across spatial scales and time.
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Affiliation(s)
- Yuxin Zhang
- Sensory Circuits and Neurotechnology Lab, The Francis Crick Institute, London, United Kingdom
- Department of Neuroscience, Physiology and Pharmacology, University College London, London, United Kingdom
| | - Tobias Ackels
- Sensory Circuits and Neurotechnology Lab, The Francis Crick Institute, London, United Kingdom
- Department of Neuroscience, Physiology and Pharmacology, University College London, London, United Kingdom
| | - Alexandra Pacureanu
- Sensory Circuits and Neurotechnology Lab, The Francis Crick Institute, London, United Kingdom
- Department of Neuroscience, Physiology and Pharmacology, University College London, London, United Kingdom
- ESRF, The European Synchrotron, Grenoble, France
| | - Marie-Christine Zdora
- Department of Physics and Astronomy, University College London, London, United Kingdom
- Diamond Light Source, Harwell Science and Innovation Campus, Didcot, United Kingdom
- School of Physics and Astronomy, University of Southampton, Highfield Campus, Southampton, United Kingdom
- Paul Scherrer Institut, Villigen, Switzerland
| | - Anne Bonnin
- Paul Scherrer Institut, Villigen, Switzerland
| | - Andreas T. Schaefer
- Sensory Circuits and Neurotechnology Lab, The Francis Crick Institute, London, United Kingdom
- Department of Neuroscience, Physiology and Pharmacology, University College London, London, United Kingdom
| | - Carles Bosch
- Sensory Circuits and Neurotechnology Lab, The Francis Crick Institute, London, United Kingdom
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4
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Barral DC, Staiano L, Guimas Almeida C, Cutler DF, Eden ER, Futter CE, Galione A, Marques ARA, Medina DL, Napolitano G, Settembre C, Vieira OV, Aerts JMFG, Atakpa‐Adaji P, Bruno G, Capuozzo A, De Leonibus E, Di Malta C, Escrevente C, Esposito A, Grumati P, Hall MJ, Teodoro RO, Lopes SS, Luzio JP, Monfregola J, Montefusco S, Platt FM, Polishchuck R, De Risi M, Sambri I, Soldati C, Seabra MC. Current methods to analyze lysosome morphology, positioning, motility and function. Traffic 2022; 23:238-269. [PMID: 35343629 PMCID: PMC9323414 DOI: 10.1111/tra.12839] [Citation(s) in RCA: 37] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 03/21/2022] [Accepted: 03/22/2022] [Indexed: 01/09/2023]
Abstract
Since the discovery of lysosomes more than 70 years ago, much has been learned about the functions of these organelles. Lysosomes were regarded as exclusively degradative organelles, but more recent research has shown that they play essential roles in several other cellular functions, such as nutrient sensing, intracellular signalling and metabolism. Methodological advances played a key part in generating our current knowledge about the biology of this multifaceted organelle. In this review, we cover current methods used to analyze lysosome morphology, positioning, motility and function. We highlight the principles behind these methods, the methodological strategies and their advantages and limitations. To extract accurate information and avoid misinterpretations, we discuss the best strategies to identify lysosomes and assess their characteristics and functions. With this review, we aim to stimulate an increase in the quantity and quality of research on lysosomes and further ground-breaking discoveries on an organelle that continues to surprise and excite cell biologists.
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Affiliation(s)
- Duarte C. Barral
- CEDOC, NOVA Medical School, NMS, Universidade NOVA de LisboaLisbonPortugal
| | - Leopoldo Staiano
- Telethon Institute of Genetics and Medicine (TIGEM)PozzuoliItaly
- Institute for Genetic and Biomedical ResearchNational Research Council (CNR)MilanItaly
| | | | - Dan F. Cutler
- MRC Laboratory for Molecular Cell BiologyUniversity College LondonLondonUK
| | - Emily R. Eden
- University College London (UCL) Institute of OphthalmologyLondonUK
| | - Clare E. Futter
- University College London (UCL) Institute of OphthalmologyLondonUK
| | | | | | - Diego Luis Medina
- Telethon Institute of Genetics and Medicine (TIGEM)PozzuoliItaly
- Medical Genetics Unit, Department of Medical and Translational ScienceFederico II UniversityNaplesItaly
| | - Gennaro Napolitano
- Telethon Institute of Genetics and Medicine (TIGEM)PozzuoliItaly
- Medical Genetics Unit, Department of Medical and Translational ScienceFederico II UniversityNaplesItaly
| | - Carmine Settembre
- Telethon Institute of Genetics and Medicine (TIGEM)PozzuoliItaly
- Clinical Medicine and Surgery DepartmentFederico II UniversityNaplesItaly
| | - Otília V. Vieira
- CEDOC, NOVA Medical School, NMS, Universidade NOVA de LisboaLisbonPortugal
| | | | | | - Gemma Bruno
- Telethon Institute of Genetics and Medicine (TIGEM)PozzuoliItaly
| | | | - Elvira De Leonibus
- Telethon Institute of Genetics and Medicine (TIGEM)PozzuoliItaly
- Institute of Biochemistry and Cell Biology, CNRRomeItaly
| | - Chiara Di Malta
- Telethon Institute of Genetics and Medicine (TIGEM)PozzuoliItaly
- Medical Genetics Unit, Department of Medical and Translational ScienceFederico II UniversityNaplesItaly
| | | | | | - Paolo Grumati
- Telethon Institute of Genetics and Medicine (TIGEM)PozzuoliItaly
| | - Michael J. Hall
- CEDOC, NOVA Medical School, NMS, Universidade NOVA de LisboaLisbonPortugal
| | - Rita O. Teodoro
- CEDOC, NOVA Medical School, NMS, Universidade NOVA de LisboaLisbonPortugal
| | - Susana S. Lopes
- CEDOC, NOVA Medical School, NMS, Universidade NOVA de LisboaLisbonPortugal
| | - J. Paul Luzio
- Cambridge Institute for Medical ResearchUniversity of CambridgeCambridgeUK
| | | | | | | | | | - Maria De Risi
- Telethon Institute of Genetics and Medicine (TIGEM)PozzuoliItaly
| | - Irene Sambri
- Telethon Institute of Genetics and Medicine (TIGEM)PozzuoliItaly
- Medical Genetics Unit, Department of Medical and Translational ScienceFederico II UniversityNaplesItaly
| | - Chiara Soldati
- Telethon Institute of Genetics and Medicine (TIGEM)PozzuoliItaly
| | - Miguel C. Seabra
- CEDOC, NOVA Medical School, NMS, Universidade NOVA de LisboaLisbonPortugal
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5
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Luján R, Merchán-Pérez A, Soriano J, Martín-Belmonte A, Aguado C, Alfaro-Ruiz R, Moreno-Martínez AE, DeFelipe J. Neuron Class and Target Variability in the Three-Dimensional Localization of SK2 Channels in Hippocampal Neurons as Detected by Immunogold FIB-SEM. Front Neuroanat 2022; 15:781314. [PMID: 34975419 PMCID: PMC8715088 DOI: 10.3389/fnana.2021.781314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Accepted: 11/19/2021] [Indexed: 11/22/2022] Open
Abstract
Small-conductance calcium-activated potassium (SK) channels are crucial for learning and memory. However, many aspects of their spatial organization in neurons are still unknown. In this study, we have taken a novel approach to answering these questions combining a pre-embedding immunogold labeling with an automated dual-beam electron microscope that integrates focused ion beam milling and scanning electron microscopy (FIB/SEM) to gather 3D map ultrastructural and biomolecular information simultaneously. Using this new approach, we evaluated the number and variability in the density of extrasynaptic SK2 channels in 3D reconstructions from six dendritic segments of excitatory neurons and six inhibitory neurons present in the stratum radiatum of the CA1 region of the mouse. SK2 immunoparticles were observed throughout the surface of hippocampal neurons, either scattered or clustered, as well as at intracellular sites. Quantitative volumetric evaluations revealed that the extrasynaptic SK2 channel density in spines was seven times higher than in dendritic shafts and thirty-five times higher than in interneurons. Spines showed a heterogeneous population of SK2 expression, some spines having a high SK2 content, others having a low content and others lacking SK2 channels. SK2 immunonegative spines were significantly smaller than those immunopositive. These results show that SK2 channel density differs between excitatory and inhibitory neurons and demonstrates a large variability in the density of SK2 channels in spines. Furthermore, we demonstrated that SK2 expression was associated with excitatory synapses, but not with inhibitory synapses in CA1 pyramidal cells. Consequently, regulation of excitability and synaptic plasticity by SK2 channels is expected to be neuron class- and target-specific. These data show that immunogold FIB/SEM represent a new powerful EM tool to correlate structure and function of ion channels with nanoscale resolution.
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Affiliation(s)
- Rafael Luján
- Synaptic Structure Laboratory, Instituto de Investigación en Discapacidades Neurológicas (IDINE), Departamento de Ciencias Médicas, Facultad de Medicina, Universidad Castilla-La Mancha, Albacete, Spain
| | - Angel Merchán-Pérez
- Laboratorio Cajal de Circuitos Corticales, Centro de Tecnología Biomédica, Universidad Politécnica de Madrid, Madrid, Spain
| | - Joaquim Soriano
- CRIB-Facultad de Medicina, Universidad Castilla-La Mancha, Albacete, Spain
| | - Alejandro Martín-Belmonte
- Synaptic Structure Laboratory, Instituto de Investigación en Discapacidades Neurológicas (IDINE), Departamento de Ciencias Médicas, Facultad de Medicina, Universidad Castilla-La Mancha, Albacete, Spain
| | - Carolina Aguado
- Synaptic Structure Laboratory, Instituto de Investigación en Discapacidades Neurológicas (IDINE), Departamento de Ciencias Médicas, Facultad de Medicina, Universidad Castilla-La Mancha, Albacete, Spain
| | - Rocío Alfaro-Ruiz
- Synaptic Structure Laboratory, Instituto de Investigación en Discapacidades Neurológicas (IDINE), Departamento de Ciencias Médicas, Facultad de Medicina, Universidad Castilla-La Mancha, Albacete, Spain
| | - Ana Esther Moreno-Martínez
- Synaptic Structure Laboratory, Instituto de Investigación en Discapacidades Neurológicas (IDINE), Departamento de Ciencias Médicas, Facultad de Medicina, Universidad Castilla-La Mancha, Albacete, Spain
| | - Javier DeFelipe
- Laboratorio Cajal de Circuitos Corticales, Centro de Tecnología Biomédica, Universidad Politécnica de Madrid, Madrid, Spain.,Instituto Cajal (CSIC), Madrid, Spain
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6
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Parlanti P, Cappello V. Microscopes, tools, probes, and protocols: A guide in the route of correlative microscopy for biomedical investigation. Micron 2021; 152:103182. [PMID: 34801960 DOI: 10.1016/j.micron.2021.103182] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 11/12/2021] [Accepted: 11/14/2021] [Indexed: 12/11/2022]
Abstract
In the last decades, the advancements of microscopes technology, together with the development of new imaging approaches, are trying to address some biological questions that have been unresolved in the past: the need to combine in the same analysis temporal, functional and morphological information on the biological sample has become pressing. For this reason, the use of correlative microscopy, in which two or more imaging techniques are combined in the same analysis, is getting increasingly widespread. In fact, correlative microscopy can overcome limitations of a single imaging method, giving access to a larger amount of information from the same specimen. However, correlative microscopy can be challenging, and appropriate protocols for sample preparation and imaging methods must be selected. Here we review the state of the art of correlating electron microscopy with different imaging methods, focusing on sample preparation, tools, and labeling methods, with the aim to provide a comprehensive guide for those scientists who are approaching the field of correlative methods.
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Affiliation(s)
- Paola Parlanti
- Istituto Italiano di Tecnologia, Center for Materials Interfaces, Electron Crystallography, Viale Rinaldo Piaggio 34, I-56025, Pontedera (PI), Italy.
| | - Valentina Cappello
- Istituto Italiano di Tecnologia, Center for Materials Interfaces, Electron Crystallography, Viale Rinaldo Piaggio 34, I-56025, Pontedera (PI), Italy.
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7
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Endo M, Maruoka H, Okabe S. Advanced Technologies for Local Neural Circuits in the Cerebral Cortex. Front Neuroanat 2021; 15:757499. [PMID: 34803616 PMCID: PMC8595196 DOI: 10.3389/fnana.2021.757499] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Accepted: 10/13/2021] [Indexed: 11/13/2022] Open
Abstract
The neural network in the brain can be viewed as an integrated system assembled from a large number of local neural circuits specialized for particular brain functions. Activities of neurons in local neural circuits are thought to be organized both spatially and temporally under the rules optimized for their roles in information processing. It is well perceived that different areas of the mammalian neocortex have specific cognitive functions and distinct computational properties. However, the organizational principles of the local neural circuits in different cortical regions have not yet been clarified. Therefore, new research principles and related neuro-technologies that enable efficient and precise recording of large-scale neuronal activities and synaptic connections are necessary. Innovative technologies for structural analysis, including tissue clearing and expansion microscopy, have enabled super resolution imaging of the neural circuits containing thousands of neurons at a single synapse resolution. The imaging resolution and volume achieved by new technologies are beyond the limits of conventional light or electron microscopic methods. Progress in genome editing and related technologies has made it possible to label and manipulate specific cell types and discriminate activities of multiple cell types. These technologies will provide a breakthrough for multiscale analysis of the structure and function of local neural circuits. This review summarizes the basic concepts and practical applications of the emerging technologies and new insight into local neural circuits obtained by these technologies.
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Affiliation(s)
| | | | - Shigeo Okabe
- Department of Cellular Neurobiology, Graduate School of Medicine and Faculty of Medicine, The University of Tokyo, Tokyo, Japan
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8
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Courson JA, Landry PT, Do T, Spehlmann E, Lafontant PJ, Patel N, Rumbaut RE, Burns AR. Serial Block-Face Scanning Electron Microscopy (SBF-SEM) of Biological Tissue Samples. J Vis Exp 2021:10.3791/62045. [PMID: 33843931 PMCID: PMC8225236 DOI: 10.3791/62045] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Serial block-face scanning electron microscopy (SBF-SEM) allows for the collection of hundreds to thousands of serially-registered ultrastructural images, offering an unprecedented three-dimensional view of tissue microanatomy. While SBF-SEM has seen an exponential increase in use in recent years, technical aspects such as proper tissue preparation and imaging parameters are paramount for the success of this imaging modality. This imaging system benefits from the automated nature of the device, allowing one to leave the microscope unattended during the imaging process, with the automated collection of hundreds of images possible in a single day. However, without appropriate tissue preparation cellular ultrastructure can be altered in such a way that incorrect or misleading conclusions might be drawn. Additionally, images are generated by scanning the block-face of a resin-embedded biological sample and this often presents challenges and considerations that must be addressed. The accumulation of electrons within the block during imaging, known as "tissue charging," can lead to a loss of contrast and an inability to appreciate cellular structure. Moreover, while increasing electron beam intensity/voltage or decreasing beam-scanning speed can increase image resolution, this can also have the unfortunate side effect of damaging the resin block and distorting subsequent images in the imaging series. Here we present a routine protocol for the preparation of biological tissue samples that preserves cellular ultrastructure and diminishes tissue charging. We also provide imaging considerations for the rapid acquisition of high-quality serial-images with minimal damage to the tissue block.
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Affiliation(s)
- Justin A. Courson
- University of Houston, College of Optometry, Houston, TX,
United States of America
| | - Paul T. Landry
- University of Houston, College of Optometry, Houston, TX,
United States of America
| | - Thao Do
- University of Houston, College of Optometry, Houston, TX,
United States of America
| | - Eric Spehlmann
- DePauw University, Department of Biology, Greencastle, IN,
United States of America
| | - Pascal J. Lafontant
- DePauw University, Department of Biology, Greencastle, IN,
United States of America
| | - Nimesh Patel
- University of Houston, College of Optometry, Houston, TX,
United States of America
| | - Rolando E. Rumbaut
- Center for Translational Research on Inflammatory Diseases
(CTRID), Michael E. DeBakey Veterans Affairs Medical Center, Houston, TX, United
States of America,Baylor College of Medicine, Children’s Nutrition
Center, Houston, TX, United States of America
| | - Alan R. Burns
- University of Houston, College of Optometry, Houston, TX,
United States of America,Baylor College of Medicine, Children’s Nutrition
Center, Houston, TX, United States of America
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9
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Kawasaki Y, Hosoyamada Y, Miyaki T, Yamaguchi J, Kakuta S, Sakai T, Ichimura K. Three-Dimensional Architecture of Glomerular Endothelial Cells Revealed by FIB-SEM Tomography. Front Cell Dev Biol 2021; 9:653472. [PMID: 33777962 PMCID: PMC7991748 DOI: 10.3389/fcell.2021.653472] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 02/04/2021] [Indexed: 11/29/2022] Open
Abstract
Focused-ion beam-scanning electron microscopic (FIB-SEM) tomography enables easier acquisition of a series of ultrastructural, sectional images directly from resin-embedded biological samples. In this study, to clarify the three-dimensional (3D) architecture of glomerular endothelial cells (GEnCs) in adult rats, we manually extracted GEnCs from serial FIB-SEM images and reconstructed them on an Amira reconstruction software. The luminal and basal surface structures were clearly visualized in the reconstructed GEnCs, although only the luminal surface structures could be observed by conventional SEM. The luminal surface visualized via the reconstructed GEnCs was quite similar to that observed through conventional SEM, indicating that 3D reconstruction could be performed with high accuracy. Thus, we successfully described the 3D architecture of normal GEnCs in adult rats more clearly and precisely than ever before. The GEnCs were found to consist of three major subcellular compartments, namely, the cell body, cytoplasmic ridges, and sieve plates, in addition to two associated subcellular compartments, namely, the globular protrusions and reticular porous structures. Furthermore, most individual GEnCs made up a “seamless” tubular shape, and some of them formed an autocellular junction to make up a tubular shape. FIB-SEM tomography with reconstruction is a powerful approach to better understand the 3D architecture of GEnCs. Moreover, the morphological information revealed in this study will be valuable for the 3D pathologic evaluation of GEnCs in animal and human glomerular diseases and the structural analysis of developmental processes in the glomerular capillary system.
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Affiliation(s)
- Yuto Kawasaki
- Department of Anatomy and Life Structure, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Yasue Hosoyamada
- Department of Anatomy and Life Structure, Juntendo University Graduate School of Medicine, Tokyo, Japan.,Department of Nutrition, Faculty of Health Care Sciences, Chiba Prefectural University of Health Sciences, Chiba, Japan
| | - Takayuki Miyaki
- Department of Anatomy and Life Structure, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Junji Yamaguchi
- Laboratory of Morphology and Image Analysis, Research Support Center, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Soichiro Kakuta
- Laboratory of Morphology and Image Analysis, Research Support Center, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Tatsuo Sakai
- Department of Anatomy and Life Structure, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Koichiro Ichimura
- Department of Anatomy and Life Structure, Juntendo University Graduate School of Medicine, Tokyo, Japan.,Laboratory of Morphology and Image Analysis, Research Support Center, Juntendo University Graduate School of Medicine, Tokyo, Japan
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10
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Miyaki T, Kawasaki Y, Matsumoto A, Kakuta S, Sakai T, Ichimura K. Nephrocytes are part of the spectrum of filtration epithelial diversity. Cell Tissue Res 2020; 382:609-625. [PMID: 33191456 PMCID: PMC7683493 DOI: 10.1007/s00441-020-03313-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 09/24/2020] [Indexed: 12/15/2022]
Abstract
The excretory system produces urine by ultrafiltration via a filtration epithelium. Podocytes are widely found as filtration epithelial cells in eucoelomates. In some animal taxa, including insects and crustaceans, nephrocytes serve to separate toxic substances from the body fluid, in addition to podocytes. Drosophila nephrocytes have been recently utilized as a model system to study podocyte function and disease. However, functionality and cellular architecture are strikingly different between Drosophila nephrocytes and eucoelomate podocytes, and the phylogenetic relationship between these cells remains enigmatic. In this study, using focused-ion beam-scanning electron microscopy (FIB-SEM) tomography, we revealed three-dimensional architecture of decapod nephrocytes with unprecedented accuracy—they filled an enormous gap, which can be called “missing link,” in the evolutionary diversity of podocytes and nephrocytes. Thus, we concluded that nephrocytes are part of the spectrum of filtration epithelial diversity in animal phylogeny.
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Affiliation(s)
- Takayuki Miyaki
- Department of Anatomy and Life Structure, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Yuto Kawasaki
- Department of Anatomy and Life Structure, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Akira Matsumoto
- Department of Biology, Juntendo University School of Medicine, Inzai, Chiba, Japan
| | - Soichiro Kakuta
- Laboratory of Morphology and Image Analysis, Center for Biomedical Research Resources, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Tatsuo Sakai
- Department of Anatomy and Life Structure, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Koichiro Ichimura
- Department of Anatomy and Life Structure, Juntendo University Graduate School of Medicine, Tokyo, Japan. .,Laboratory of Morphology and Image Analysis, Center for Biomedical Research Resources, Juntendo University Graduate School of Medicine, Tokyo, Japan.
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11
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Goggin P, Ho EML, Gnaegi H, Searle S, Oreffo ROC, Schneider P. Development of protocols for the first serial block-face scanning electron microscopy (SBF SEM) studies of bone tissue. Bone 2020; 131:115107. [PMID: 31669251 PMCID: PMC6961117 DOI: 10.1016/j.bone.2019.115107] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Revised: 09/27/2019] [Accepted: 10/09/2019] [Indexed: 11/28/2022]
Abstract
There is an unmet need for a high-resolution three-dimensional (3D) technique to simultaneously image osteocytes and the matrix in which these cells reside. In serial block-face scanning electron microscopy (SBF SEM), an ultramicrotome mounted within the vacuum chamber of a microscope repeatedly sections a resin-embedded block of tissue. Backscattered electron scans of the block face provide a stack of high-resolution two-dimensional images, which can be used to visualise and quantify cells and organelles in 3D. High-resolution 3D images of biological tissues from SBF SEM have been exploited considerably to date in the neuroscience field. However, non-brain samples, in particular hard biological tissues, have appeared more challenging to image by SBF SEM due to the difficulties of sectioning and rendering the samples conductive. We have developed and propose protocols for bone tissue preparation using SBF SEM, for imaging simultaneously soft and hard bone tissue components in 3D. We review the state of the art in high-resolution imaging of osteocytes, provide a historical perspective of SBF SEM, and we present first SBF SEM proof-of-concept studies for murine and human tissue. The application of SBF SEM to hard tissues will facilitate qualitative and quantitative 3D studies of tissue microstructure and ultrastructure in bone development, ageing and pathologies such as osteoporosis and osteoarthritis.
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Affiliation(s)
- Patricia Goggin
- Bioengineering Science Research Group, Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, UK
| | - Elaine M L Ho
- Bioengineering Science Research Group, Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, UK
| | | | | | - Richard O C Oreffo
- Bone and Joint Research Group, Centre for Human Development, Stem Cells and Regeneration, Faculty of Medicine, University of Southampton, Southampton, UK
| | - Philipp Schneider
- Bioengineering Science Research Group, Faculty of Engineering and Physical Sciences, University of Southampton, Southampton, UK.
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12
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An Effective Microscopic Detection Method for Automated Silicon-Substrate Ultra-microtome (ASUM). Neural Process Lett 2019. [DOI: 10.1007/s11063-019-10134-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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13
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Zhao Y, Liu X, Chen B, Yang F, Zhang Y, Wang P, Robinson I. Three-Dimensional Characterization of Hardened Paste of Hydrated Tricalcium Silicate by Serial Block-Face Scanning Electron Microscopy. MATERIALS (BASEL, SWITZERLAND) 2019; 12:E1882. [PMID: 31212729 PMCID: PMC6631706 DOI: 10.3390/ma12121882] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/19/2019] [Revised: 05/31/2019] [Accepted: 06/03/2019] [Indexed: 11/24/2022]
Abstract
With the application of a three-dimensional (3D) characterization technique, serial block-face scanning electron microscopy (SBFSEM), the 3D microstructure of a hydrated cement monomineral, tricalcium silicate (C3S), was measured with nanoscale resolution. The 3D morphologies of anhydrous particles, hydrated products, and capillary pores were visualized. Closed and open pores were discovered inside an anhydrous particle. The size and distribution of both the anhydrous C3S particles and their capillary pores were analyzed quantitatively and the porosity was determined to be 9%. The distribution of pores was found to be in a good agreement with the inner and outer product model of Hu et. al., with an inner shell distance of 860 nm. Considering the spatial resolution of the instrument and the volume of sample measured, most pores in this experiment could be characterized as capillary pores.
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Affiliation(s)
- Yongjuan Zhao
- School of Materials Science and Engineering, Tongji University, Shanghai 201804, China.
| | - Xianping Liu
- School of Materials Science and Engineering, Tongji University, Shanghai 201804, China.
- Key Laboratory of Advanced Civil Engineering Materials (Tongji University), Ministry of Education, Shanghai 201804, China.
| | - Bo Chen
- School of Materials Science and Engineering, Tongji University, Shanghai 201804, China.
- Key Laboratory of Advanced Civil Engineering Materials (Tongji University), Ministry of Education, Shanghai 201804, China.
- London Centre for Nanotechnology, University College London, London WC1H 0AH, UK.
| | - Fei Yang
- School of Materials Science and Engineering, Tongji University, Shanghai 201804, China.
| | - Yongming Zhang
- School of Materials Science and Engineering, Tongji University, Shanghai 201804, China.
- Key Laboratory of Advanced Civil Engineering Materials (Tongji University), Ministry of Education, Shanghai 201804, China.
| | - Peiming Wang
- School of Materials Science and Engineering, Tongji University, Shanghai 201804, China.
| | - Ian Robinson
- School of Materials Science and Engineering, Tongji University, Shanghai 201804, China.
- London Centre for Nanotechnology, University College London, London WC1H 0AH, UK.
- Division of Condensed Matter Physics and Materials Science, Brookhaven National Laboratory, Upton, NY 11973, USA.
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14
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Kubota Y, Sohn J, Kawaguchi Y. Large Volume Electron Microscopy and Neural Microcircuit Analysis. Front Neural Circuits 2018; 12:98. [PMID: 30483066 PMCID: PMC6240581 DOI: 10.3389/fncir.2018.00098] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Accepted: 10/17/2018] [Indexed: 12/23/2022] Open
Abstract
One recent technical innovation in neuroscience is microcircuit analysis using three-dimensional reconstructions of neural elements with a large volume Electron microscopy (EM) data set. Large-scale data sets are acquired with newly-developed electron microscope systems such as automated tape-collecting ultramicrotomy (ATUM) with scanning EM (SEM), serial block-face EM (SBEM) and focused ion beam-SEM (FIB-SEM). Currently, projects are also underway to develop computer applications for the registration and segmentation of the serially-captured electron micrographs that are suitable for analyzing large volume EM data sets thoroughly and efficiently. The analysis of large volume data sets can bring innovative research results. These recently available techniques promote our understanding of the functional architecture of the brain.
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Affiliation(s)
- Yoshiyuki Kubota
- Division of Cerebral Circuitry, National Institute for Physiological Sciences (NIPS), Okazaki, Japan
- Department of Physiological Sciences, The Graduate University for Advanced Studies (SOKENDAI), Okazaki, Japan
| | - Jaerin Sohn
- Division of Cerebral Circuitry, National Institute for Physiological Sciences (NIPS), Okazaki, Japan
- Research Fellow of Japan Society for the Promotion of Science (JSPS), Tokyo, Japan
| | - Yasuo Kawaguchi
- Division of Cerebral Circuitry, National Institute for Physiological Sciences (NIPS), Okazaki, Japan
- Department of Physiological Sciences, The Graduate University for Advanced Studies (SOKENDAI), Okazaki, Japan
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15
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Biological serial block face scanning electron microscopy at improved z-resolution based on Monte Carlo model. Sci Rep 2018; 8:12985. [PMID: 30154532 PMCID: PMC6113311 DOI: 10.1038/s41598-018-31231-w] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Accepted: 08/10/2018] [Indexed: 12/12/2022] Open
Abstract
Serial block-face electron microscopy (SBEM) provides nanoscale 3D ultrastructure of embedded and stained cells and tissues in volumes of up to 107 µm3. In SBEM, electrons with 1–3 keV energies are incident on a specimen block, from which backscattered electron (BSE) images are collected with x, y resolution of 5–10 nm in the block-face plane, and successive layers are removed by an in situ ultramicrotome. Spatial resolution along the z-direction, however, is limited to around 25 nm by the minimum cutting thickness. To improve the z-resolution, we have extracted depth information from BSE images acquired at dual primary beam energies, using Monte Carlo simulations of electron scattering. The relationship between depth of stain and ratio of dual-energy BSE intensities enables us to determine 3D structure with a ×2 improvement in z-resolution. We demonstrate the technique by sub-slice imaging of hepatocyte membranes in liver tissue.
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16
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Kubota Y, Sohn J, Hatada S, Schurr M, Straehle J, Gour A, Neujahr R, Miki T, Mikula S, Kawaguchi Y. A carbon nanotube tape for serial-section electron microscopy of brain ultrastructure. Nat Commun 2018; 9:437. [PMID: 29382816 PMCID: PMC5789869 DOI: 10.1038/s41467-017-02768-7] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2017] [Accepted: 12/26/2017] [Indexed: 01/09/2023] Open
Abstract
Automated tape-collecting ultramicrotomy in conjunction with scanning electron microscopy (SEM) is a powerful approach for volume electron microscopy and three-dimensional neuronal circuit analysis. Current tapes are limited by section wrinkle formation, surface scratches and sample charging during imaging. Here we show that a plasma-hydrophilized carbon nanotube (CNT)-coated polyethylene terephthalate (PET) tape effectively resolves these issues and produces SEM images of comparable quality to those from transmission electron microscopy. CNT tape can withstand multiple rounds of imaging, offer low surface resistance across the entire tape length and generate no wrinkles during the collection of ultrathin sections. When combined with an enhanced en bloc staining protocol, CNT tape-processed brain sections reveal detailed synaptic ultrastructure. In addition, CNT tape is compatible with post-embedding immunostaining for light and electron microscopy. We conclude that CNT tape can enable high-resolution volume electron microscopy for brain ultrastructure analysis.
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Affiliation(s)
- Yoshiyuki Kubota
- Division of Cerebral Circuitry, National Institute for Physiological Sciences, 5-1 Myodaiji-Higashiyama, Okazaki, Aichi, 444-8787, Japan. .,Department of Physiological Sciences, The Graduate University for Advanced Studies (SOKENDAI), 5-1 Myodaiji-Higashiyama, Okazaki, Aichi, 444-8787, Japan.
| | - Jaerin Sohn
- Division of Cerebral Circuitry, National Institute for Physiological Sciences, 5-1 Myodaiji-Higashiyama, Okazaki, Aichi, 444-8787, Japan.,Research Fellow of Japan Society for the Promotion of Science (JSPS), 5-3-1 Kojimachi, Chiyoda-ku, Tokyo, 102-0083, Japan
| | - Sayuri Hatada
- Division of Cerebral Circuitry, National Institute for Physiological Sciences, 5-1 Myodaiji-Higashiyama, Okazaki, Aichi, 444-8787, Japan
| | - Meike Schurr
- Department of Connectomics, Max-Planck Institute for Brain Research, Max-von-Laue-Str. 4, D-60438, Frankfurt, Germany
| | - Jakob Straehle
- Department of Connectomics, Max-Planck Institute for Brain Research, Max-von-Laue-Str. 4, D-60438, Frankfurt, Germany
| | - Anjali Gour
- Department of Connectomics, Max-Planck Institute for Brain Research, Max-von-Laue-Str. 4, D-60438, Frankfurt, Germany
| | - Ralph Neujahr
- Carl Zeiss Microscopy GmbH, ZEISS Microscopy Customer Center Europe, Rudolph-Eber-Str. 2, D- 873447, Oberkochen, Germany
| | - Takafumi Miki
- Graduate School of Brain Science, Doshisha University, 1-3 Tatara Miyakodani, Kyotanabe, Kyoto, 610-0394, Japan
| | - Shawn Mikula
- Electrons-Photons-Neurons, Max-Planck Institute of Neurobiology, Am Klopferspitz 18, D-82152, Martinsried, Germany
| | - Yasuo Kawaguchi
- Division of Cerebral Circuitry, National Institute for Physiological Sciences, 5-1 Myodaiji-Higashiyama, Okazaki, Aichi, 444-8787, Japan.,Department of Physiological Sciences, The Graduate University for Advanced Studies (SOKENDAI), 5-1 Myodaiji-Higashiyama, Okazaki, Aichi, 444-8787, Japan
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17
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Xu J, Long H, Chen W, Cheng X, Yu H, Huang Y, Wang X, Li F. Ultrastructural Features of Neurovascular Units in a Rat Model of Chronic Compressive Spinal Cord Injury. Front Neuroanat 2018; 11:136. [PMID: 29375327 PMCID: PMC5767600 DOI: 10.3389/fnana.2017.00136] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Accepted: 12/26/2017] [Indexed: 12/16/2022] Open
Abstract
Chronic spinal cord compression is the most common cause of spinal cord impairment worldwide. Objective of this study is to assess the ultrastructural features of the neurovascular unit (NVU) in a rat model of chronic compressive spinal cord injury, 24 SD rats were divided into two groups: the control group (n = 12), and the compression group (n = 12). A C6 semi-laminectomy was performed in the control group, whereas a water-absorbent polyurethane polymer was implanted into the C6 epidural space in the compression group. The Basso Beattie Bresnahan (BBB) scores and the somatosensory evoked potentials (SEP) were used to evaluate neurological functions. Transmission Electron Microscopy (TEM) was performed to investigate the change of NVU at the 28th day after modeling. Compared with the control group, the compression group shows a significant reduction (P < 0.05) of BBB score and a significant severity (P < 0.05) of abnormal SEP. TEM results of the compression group showed a striking increase in endothelial caveolae and vacuoles; a number of small spaces in tight junctions; a significant increase in pericyte processing area and vessel coverage; an expansion of the basement membrane region; swollen astrocyte endfeet and mitochondria; and the degeneration of neurons and axons. Our study revealed that damage to NVU components occurred followed by chronic compressive spinal cord injury. Several compensatory changes characterized by thicker endothelium, expansive BM, increased pericyte processing area and vessel coverage were also observed.
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Affiliation(s)
- Jinghui Xu
- Department of Spine Surgery, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China
| | - Houqing Long
- Department of Spine Surgery, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China
| | - Wenli Chen
- Department of Spine Surgery, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China
| | - Xing Cheng
- Department of Spine Surgery, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China
| | - Haoyang Yu
- Department of Spine Surgery, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China
| | - Yangliang Huang
- Department of Spine Surgery, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China
| | - Xiaobo Wang
- Department of Spine Surgery, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China
| | - Fobao Li
- Department of Spine Surgery, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Orthopedics and Traumatology, The First Affiliated Hospital of Sun Yat-Sen University, Guangzhou, China
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18
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Schlegel P, Costa M, Jefferis GS. Learning from connectomics on the fly. CURRENT OPINION IN INSECT SCIENCE 2017; 24:96-105. [PMID: 29208230 DOI: 10.1016/j.cois.2017.09.011] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Revised: 09/18/2017] [Accepted: 09/19/2017] [Indexed: 06/07/2023]
Abstract
Parallels between invertebrates and vertebrates in nervous system development, organisation and circuits are powerful reasons to use insects to study the mechanistic basis of behaviour. The last few years have seen the generation in Drosophila melanogaster of very large light microscopy data sets, genetic driver lines and tools to report or manipulate neural activity. These resources in conjunction with computational tools are enabling large scale characterisation of neuronal types and their functional properties. These are complemented by 3D electron microscopy, providing synaptic resolution data. A whole brain connectome of the fly larva is approaching completion based on manual reconstruction of electron-microscopy data. An adult whole brain dataset is already publicly available and focussed reconstruction is under way, but its 40× greater volume would require ∼500-5000 person-years of manual labour. Nevertheless rapid technical improvements in imaging and especially automated segmentation will likely deliver a complete adult connectome in the next 5 years. To enhance our understanding of the circuit basis of behaviour, light and electron microscopy outputs must be integrated with functional and physiological information into comprehensive databases. We review presently available data, tools and opportunities in Drosophila. We then consider the limits and potential of future progress and how this may impact neuroscience in rich model systems provided by larger insects and vertebrates.
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Affiliation(s)
- Philipp Schlegel
- Drosophila Connectomics Group, Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK
| | - Marta Costa
- Drosophila Connectomics Group, Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK.
| | - Gregory Sxe Jefferis
- Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge CB2 0QH, UK; Drosophila Connectomics Group, Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK.
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19
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Rist A, Thum AS. A map of sensilla and neurons in the taste system ofdrosophilalarvae. J Comp Neurol 2017; 525:3865-3889. [DOI: 10.1002/cne.24308] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2017] [Revised: 08/03/2017] [Accepted: 08/04/2017] [Indexed: 11/06/2022]
Affiliation(s)
- Anna Rist
- Department of Biology; University of Konstanz; Konstanz Germany
| | - Andreas S. Thum
- Department of Biology; University of Konstanz; Konstanz Germany
- Zukunftskolleg, University of Konstanz; Konstanz Germany
- Department of Genetics; University of Leipzig; Leipzig Germany
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20
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Oi T, Enomoto S, Nakao T, Arai S, Yamane K, Taniguchi M. Three-dimensional intracellular structure of a whole rice mesophyll cell observed with FIB-SEM. ANNALS OF BOTANY 2017; 120:21-28. [PMID: 28444369 PMCID: PMC5577905 DOI: 10.1093/aob/mcx036] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2016] [Accepted: 03/13/2017] [Indexed: 05/18/2023]
Abstract
BACKGROUND AND AIMS Ultrathin sections of rice leaf blades observed two-dimensionally using a transmission electron microscope (TEM) show that the chlorenchyma is composed of lobed mesophyll cells, with intricate cell boundaries, and lined with chloroplasts. The lobed cell shape and chloroplast positioning are believed to enhance the area available for the gas exchange surface for photosynthesis in rice leaves. However, a cell image revealing the three-dimensional (3-D) ultrastructure of rice mesophyll cells has not been visualized. In this study, a whole rice mesophyll cell was observed using a focused ion beam scanning electron microscope (FIB-SEM), which provides many serial sections automatically, rapidly and correctly, thereby enabling 3-D cell structure reconstruction. METHODS Rice leaf blades were fixed chemically using the method for conventional TEM observation, embedded in resin and subsequently set in the FIB-SEM chamber. Specimen blocks were sectioned transversely using the FIB, and block-face images were captured using the SEM. The sectioning and imaging were repeated overnight for 200-500 slices (each 50 nm thick). The resultant large-volume image stacks ( x = 25 μm, y = 25 μm, z = 10-25 μm) contained one or two whole mesophyll cells. The 3-D models of whole mesophyll cells were reconstructed using image processing software. KEY RESULTS The reconstructed cell models were discoid shaped with several lobes around the cell periphery. The cell shape increased the surface area, and the ratio of surface area to volume was twice that of a cylinder having the same volume. The chloroplasts occupied half the cell volume and spread as sheets along the cell lobes, covering most of the inner cell surface, with adjacent chloroplasts in close contact with each other. CONCLUSIONS Cellular and sub-cellular ultrastructures of a whole mesophyll cell in a rice leaf blade are demonstrated three-dimensionally using a FIB-SEM. The 3-D models and numerical information support the hypothesis that rice mesophyll cells enhance their CO 2 absorption with increased cell surface and sheet-shaped chloroplasts.
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Affiliation(s)
- Takao Oi
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-8601, Japan
- For correspondence. E-mail
| | - Sakiko Enomoto
- High Voltage Electron Microscope Laboratory, Institute of Materials and Systems for Sustainability, Nagoya University, Nagoya 464-8601, Japan
| | - Tomoyo Nakao
- High Voltage Electron Microscope Laboratory, Institute of Materials and Systems for Sustainability, Nagoya University, Nagoya 464-8601, Japan
| | - Shigeo Arai
- High Voltage Electron Microscope Laboratory, Institute of Materials and Systems for Sustainability, Nagoya University, Nagoya 464-8601, Japan
| | - Koji Yamane
- Faculty of Agriculture, Kindai University, Nara 631-8505, Japan
| | - Mitsutaka Taniguchi
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-8601, Japan
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21
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Trépout S, Bastin P, Marco S. Preparation and Observation of Thick Biological Samples by Scanning Transmission Electron Tomography. J Vis Exp 2017. [PMID: 28362414 DOI: 10.3791/55215] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
This report describes a protocol for preparing thick biological specimens for further observation using a scanning transmission electron microscope. It also describes an imaging method for studying the 3D structure of thick biological specimens by scanning transmission electron tomography. The sample preparation protocol is based on conventional methods in which the sample is fixed using chemical agents, treated with a heavy atom salt contrasting agent, dehydrated in a series of ethanol baths, and embedded in resin. The specific imaging conditions for observing thick samples by scanning transmission electron microscopy are then described. Sections of the sample are observed using a through-focus method involving the collection of several images at various focal planes. This enables the recovery of in-focus information at various heights throughout the sample. This particular collection pattern is performed at each tilt angle during tomography data collection. A single image is then generated, merging the in-focus information from all the different focal planes. A classic tilt-series dataset is then generated. The advantage of the method is that the tilt-series alignment and reconstruction can be performed using standard tools. The collection of through-focal images allows the reconstruction of a 3D volume that contains all of the structural details of the sample in focus.
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Affiliation(s)
| | - Philippe Bastin
- Institut Pasteur, Trypanosome Cell Biology Unit, Department of Parasites & Insect Vectors, INSERM U1201
| | - Sergio Marco
- Institut Curie, INSERM U1196, Campus Universitaire d'Orsay
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22
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Cazemier JL, Clascá F, Tiesinga PHE. Connectomic Analysis of Brain Networks: Novel Techniques and Future Directions. Front Neuroanat 2016; 10:110. [PMID: 27881953 PMCID: PMC5101213 DOI: 10.3389/fnana.2016.00110] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Accepted: 10/25/2016] [Indexed: 12/31/2022] Open
Abstract
Brain networks, localized or brain-wide, exist only at the cellular level, i.e., between specific pre- and post-synaptic neurons, which are connected through functionally diverse synapses located at specific points of their cell membranes. "Connectomics" is the emerging subfield of neuroanatomy explicitly aimed at elucidating the wiring of brain networks with cellular resolution and a quantified accuracy. Such data are indispensable for realistic modeling of brain circuitry and function. A connectomic analysis, therefore, needs to identify and measure the soma, dendrites, axonal path, and branching patterns together with the synapses and gap junctions of the neurons involved in any given brain circuit or network. However, because of the submicron caliber, 3D complexity, and high packing density of most such structures, as well as the fact that axons frequently extend over long distances to make synapses in remote brain regions, creating connectomic maps is technically challenging and requires multi-scale approaches, Such approaches involve the combination of the most sensitive cell labeling and analysis methods available, as well as the development of new ones able to resolve individual cells and synapses with increasing high-throughput. In this review, we provide an overview of recently introduced high-resolution methods, which researchers wanting to enter the field of connectomics may consider. It includes several molecular labeling tools, some of which specifically label synapses, and covers a number of novel imaging tools such as brain clearing protocols and microscopy approaches. Apart from describing the tools, we also provide an assessment of their qualities. The criteria we use assess the qualities that tools need in order to contribute to deciphering the key levels of circuit organization. We conclude with a brief future outlook for neuroanatomic research, computational methods, and network modeling, where we also point out several outstanding issues like structure-function relations and the complexity of neural models.
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Affiliation(s)
- J Leonie Cazemier
- Department of Neuroinformatics, Donders Institute, Radboud UniversityNijmegen, Netherlands; Department of Cortical Structure and Function, Netherlands Institute for NeuroscienceAmsterdam, Netherlands
| | - Francisco Clascá
- Department of Anatomy, Histology and Neuroscience, School of Medicine, Autónoma University Madrid, Spain
| | - Paul H E Tiesinga
- Department of Neuroinformatics, Donders Institute, Radboud University Nijmegen, Netherlands
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Titze B, Genoud C. Volume scanning electron microscopy for imaging biological ultrastructure. Biol Cell 2016; 108:307-323. [DOI: 10.1111/boc.201600024] [Citation(s) in RCA: 132] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Revised: 07/13/2016] [Accepted: 07/14/2016] [Indexed: 12/01/2022]
Affiliation(s)
- Benjamin Titze
- Friedrich Miescher Institute for Biomedical Research; Basel Switzerland
| | - Christel Genoud
- Friedrich Miescher Institute for Biomedical Research; Basel Switzerland
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Ichimura K, Kakuta S, Kawasaki Y, Miyaki T, Nonami T, Miyazaki N, Nakao T, Enomoto S, Arai S, Koike M, Murata K, Sakai T. Morphological process of podocyte development revealed by block-face scanning electron microscopy. J Cell Sci 2016; 130:132-142. [PMID: 27358478 DOI: 10.1242/jcs.187815] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Accepted: 06/20/2016] [Indexed: 01/17/2023] Open
Abstract
Podocytes present a unique 3D architecture specialized for glomerular filtration. However, several 3D morphological aspects on podocyte development remain partially understood because they are difficult to reveal using conventional scanning electron microscopy (SEM). Here, we adopted serial block-face SEM imaging, a powerful tool for analyzing the 3D cellular ultrastructure, to precisely reveal the morphological process of podocyte development, such as the formation of foot processes. Development of foot processes gives rise to three morphological states: the primitive, immature and mature foot processes. Immature podocytes were columnar in shape and connected to each other by the junctional complex, which migrated toward the basal side of the cell. When the junctional complex was close to the basement membrane, immature podocytes started to interdigitate with primitive foot processes under the level of junctional complex. As primitive foot processes lengthened, the junctional complex moved between primitive foot processes to form immature foot processes. Finally, the junctional complex was gradually replaced by the slit diaphragm, resulting in the maturation of immature foot processes into mature foot processes. In conclusion, the developmental process of podocytes is now clearly visualized by block-face SEM imaging.
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Affiliation(s)
- Koichiro Ichimura
- Department of Anatomy and Life Structure, Juntendo University Graduate School of Medicine, Tokyo 113-8421, Japan
| | - Soichiro Kakuta
- Laboratory of Morphology and Image Analysis, Center for Biomedical Research Resources, Juntendo University Graduate School of Medicine, Tokyo 113-8421, Japan
| | - Yuto Kawasaki
- Department of Anatomy and Life Structure, Juntendo University Graduate School of Medicine, Tokyo 113-8421, Japan
| | - Takayuki Miyaki
- Department of Anatomy and Life Structure, Juntendo University Graduate School of Medicine, Tokyo 113-8421, Japan
| | - Takahiro Nonami
- Department of Anatomy and Life Structure, Juntendo University Graduate School of Medicine, Tokyo 113-8421, Japan
| | - Naoyuki Miyazaki
- National Institute for Physiological Sciences, Okazaki 444-8585, Japan
| | - Tomoyo Nakao
- High Voltage Electron Microscope Laboratory, Nagoya University, Nagoya 464-8603, Japan
| | - Sakiko Enomoto
- High Voltage Electron Microscope Laboratory, Nagoya University, Nagoya 464-8603, Japan
| | - Shigeo Arai
- High Voltage Electron Microscope Laboratory, Nagoya University, Nagoya 464-8603, Japan
| | - Masato Koike
- Department of Cell Biology and Neuroscience, Juntendo University Graduate School of Medicine, Tokyo 113-8421, Japan
| | - Kazuyoshi Murata
- National Institute for Physiological Sciences, Okazaki 444-8585, Japan
| | - Tatsuo Sakai
- Department of Anatomy and Life Structure, Juntendo University Graduate School of Medicine, Tokyo 113-8421, Japan
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25
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Cretoiu D, Gherghiceanu M, Hummel E, Zimmermann H, Simionescu O, Popescu LM. FIB-SEM tomography of human skin telocytes and their extracellular vesicles. J Cell Mol Med 2016; 19:714-22. [PMID: 25823591 PMCID: PMC4395186 DOI: 10.1111/jcmm.12578] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Accepted: 02/15/2015] [Indexed: 12/19/2022] Open
Abstract
We have shown in 2012 the existence of telocytes (TCs) in human dermis. TCs were described by transmission electron microscopy (TEM) as interstitial cells located in non-epithelial spaces (stroma) of many organs (see www.telocytes.com). TCs have very long prolongations (tens to hundreds micrometers) named Telopodes (Tps). These Tps have a special conformation with dilated portions named podoms (containing mitochondria, endoplasmic reticulum and caveolae) and very thin segments (below resolving power of light microscopy), called podomers. To show the real 3D architecture of TC network, we used the most advanced available electron microscope technology: focused ion beam scanning electron microscopy (FIB-SEM) tomography. Generally, 3D reconstruction of dermal TCs by FIB-SEM tomography revealed the existence of Tps with various conformations: (i) long, flattened irregular veils (ribbon-like segments) with knobs, corresponding to podoms, and (ii) tubular structures (podomers) with uneven calibre because of irregular dilations (knobs) – the podoms. FIB-SEM tomography also showed numerous extracellular vesicles (diameter 438.6 ± 149.1 nm, n = 30) released by a human dermal TC. Our data might be useful for understanding the role(s) of TCs in intercellular signalling and communication, as well as for comprehension of pathologies like scleroderma, multiple sclerosis, psoriasis, etc.
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Affiliation(s)
- Dragos Cretoiu
- Department of Cellular and Molecular Medicine, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania; Victor Babeș National Institute of Pathology, Bucharest, Romania
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26
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Nguyen HB, Thai TQ, Saitoh S, Wu B, Saitoh Y, Shimo S, Fujitani H, Otobe H, Ohno N. Conductive resins improve charging and resolution of acquired images in electron microscopic volume imaging. Sci Rep 2016; 6:23721. [PMID: 27020327 PMCID: PMC4810419 DOI: 10.1038/srep23721] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Accepted: 03/14/2016] [Indexed: 11/09/2022] Open
Abstract
Recent advances in serial block-face imaging using scanning electron microscopy (SEM) have enabled the rapid and efficient acquisition of 3-dimensional (3D) ultrastructural information from a large volume of biological specimens including brain tissues. However, volume imaging under SEM is often hampered by sample charging, and typically requires specific sample preparation to reduce charging and increase image contrast. In the present study, we introduced carbon-based conductive resins for 3D analyses of subcellular ultrastructures, using serial block-face SEM (SBF-SEM) to image samples. Conductive resins were produced by adding the carbon black filler, Ketjen black, to resins commonly used for electron microscopic observations of biological specimens. Carbon black mostly localized around tissues and did not penetrate cells, whereas the conductive resins significantly reduced the charging of samples during SBF-SEM imaging. When serial images were acquired, embedding into the conductive resins improved the resolution of images by facilitating the successful cutting of samples in SBF-SEM. These results suggest that improving the conductivities of resins with a carbon black filler is a simple and useful option for reducing charging and enhancing the resolution of images obtained for volume imaging with SEM.
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Affiliation(s)
- Huy Bang Nguyen
- Department of Anatomy and Molecular Histology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Chuo-city, Yamanashi 409-3898, Japan
| | - Truc Quynh Thai
- Department of Anatomy and Molecular Histology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Chuo-city, Yamanashi 409-3898, Japan
| | - Sei Saitoh
- Department of Anatomy and Molecular Histology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Chuo-city, Yamanashi 409-3898, Japan
| | - Bao Wu
- Department of Anatomy and Molecular Histology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Chuo-city, Yamanashi 409-3898, Japan
| | - Yurika Saitoh
- Department of Anatomy and Molecular Histology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Chuo-city, Yamanashi 409-3898, Japan
| | - Satoshi Shimo
- Department of Occupational Therapy, Health Science University, Fujikawaguchiko, Yamanashi 401-0380, Japan
| | | | - Hirohide Otobe
- Asahi Kasei Chemicals Corporation, Kawasaki-city, Kanagawa 210-0863 Japan
| | - Nobuhiko Ohno
- Department of Anatomy and Molecular Histology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Chuo-city, Yamanashi 409-3898, Japan.,Center for Multidisciplinary Brain Research, National Institute for Physiological Sciences, Okazaki, Aichi 444-8787, Japan
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27
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BORRETT S, HUGHES L. Reporting methods for processing and analysis of data from serial block face scanning electron microscopy. J Microsc 2016; 263:3-9. [DOI: 10.1111/jmi.12377] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2015] [Accepted: 12/09/2015] [Indexed: 01/13/2023]
Affiliation(s)
- S. BORRETT
- Sir William Dunn School of Pathology, South Parks Road; University of Oxford; Oxford OX1 3RE U.K
| | - L. HUGHES
- Department of Biological & Medical Sciences, Gipsy Lane; Oxford Brookes University; Oxford OX3 0BP U.K
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28
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Ohno N, Katoh M, Saitoh Y, Saitoh S. Recent advancement in the challenges to connectomics. Microscopy (Oxf) 2015; 65:97-107. [PMID: 26671942 DOI: 10.1093/jmicro/dfv371] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2015] [Accepted: 11/12/2015] [Indexed: 01/23/2023] Open
Abstract
Advancement of microscopic technologies established significant progress in our understanding of the brain. In the recent effort to elucidate the complete wiring map of the brain circuitry termed 'connectome', the different modalities of imaging technology, including those of light and electron microscopy, have started providing essential contribution in multiple organisms. The contribution would be impossible without the recent innovation in both acquisition and analyses of the big connectomic data. The current data demonstrated complicated networks with unidirectional and reciprocal connections of the cerebral circuits at the macroscopic and light microscopic ('mesoscopic') levels, and the unimaginable complexity of synaptic connections between axons and dendrites at the electron microscopic ('microscopic') level. At the same time, the data highlighted the necessity to make substantial advancement in methodology of the connectomic studies, including efficient handling and automated analyses of the acquired dataset. Further understanding about structural and functional connectome seems to be facilitated by combinations of the different imaging modalities. Such multidisciplinary approaches will give us the clues to address whether the complete connectome can elucidate fundamental mechanisms processing the basic and higher functions of human brains.
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Affiliation(s)
- Nobuhiko Ohno
- Department of Anatomy and Molecular Histology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, 1110 Shimokato, Chuo-city, Yamanashi 409-3898, Japan
| | - Mitsuhiko Katoh
- Department of Anatomy and Molecular Histology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, 1110 Shimokato, Chuo-city, Yamanashi 409-3898, Japan
| | - Yurika Saitoh
- Department of Anatomy and Molecular Histology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, 1110 Shimokato, Chuo-city, Yamanashi 409-3898, Japan
| | - Sei Saitoh
- Department of Anatomy and Molecular Histology, Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, 1110 Shimokato, Chuo-city, Yamanashi 409-3898, Japan
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Burette A, Collman F, Micheva KD, Smith SJ, Weinberg RJ. Knowing a synapse when you see one. Front Neuroanat 2015; 9:100. [PMID: 26283929 PMCID: PMC4517447 DOI: 10.3389/fnana.2015.00100] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Accepted: 07/10/2015] [Indexed: 11/22/2022] Open
Abstract
Recent years have seen a rapidly growing recognition of the complexity and diversity of the myriad individual synaptic connections that define brain synaptic networks. It has also become increasingly apparent that the synapses themselves are a major key to understanding the development, function and adaptability of those synaptic networks. In spite of this growing appreciation, the molecular, structural and functional characteristics of individual synapses and the patterning of their diverse characteristics across functional networks have largely eluded quantitative study with available imaging technologies. Here we offer an overview of new computational imaging methods that promise to bring single-synapse analysis of synaptic networks to the fore. We focus especially on the challenges and opportunities associated with quantitative detection of individual synapses and with measuring individual synapses across network scale populations in mammalian brain.
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Affiliation(s)
- Alain Burette
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill Chapel Hill, NC, USA
| | | | - Kristina D Micheva
- Department of Molecular and Cellular Physiology, Stanford University Stanford, CA, USA
| | | | - Richard J Weinberg
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill Chapel Hill, NC, USA
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