• Applied Microscopy
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• v.45 no.3
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• pp.150-154
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• 2015

Negative staining electron microscopy facilitates the visualization of small bio-materials such as proteins; thus, many electron microscopists have used this conventional method to visualize the morphologies and structures of biological materials. To achieve sufficient contrast of the materials, a number of imaging parameters must be considered. Here, we examined the effects of one of the fundamental imaging parameters, electron beam exposure time, on electron densities generated using transmission electron microscopy. A single site of a negatively stained biological sample was illuminated with the electron beam for different times (1, 2, or 4 seconds) and sets of micrographs were collected. Computational image processing demonstrated that longer exposure times provide better electron densities at the molecular level. This report describes technical procedures for testing parameters that allow enhanced evaluations of the densities of electron microscopy images.

• Applied Microscopy
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• v.47 no.4
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• pp.215-217
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• 2017

Dr. Jacques Dubochet, Dr. Joachim Frank, and Dr. Richard Henderson received the 2017 Nobel Prize for Chemistry for their efforts to develop effective ways to obtain high-resolution three-dimensional images of biomolecules using cryo-electron microscopy. Congratulations to the Nobel Prize in the field of electron microscopy, I will explain the scientific contributions of the three winners and introduce the role of cryo-electron microscopy (including cryo technology) in biology.

• Applied Microscopy
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• v.47 no.4
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• pp.226-232
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• 2017

Electron microscopy and X-ray diffraction have together played a key role in our understanding of the molecular structure and mechanism of contraction of muscle. This review highlights the role of electron microscopy, from early insights into thick and thin filament structure by negative staining, to studies of single myosin molecule structure, and finally to recent high-resolution structures by cryo-electron microscopy. Muscle filaments are designed for movement. Their labile structures thus present challenges to obtaining near-atomic detail, which are also discussed.

• Applied Microscopy
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• v.46 no.4
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• pp.171-175
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• 2016

A distinctive neuronal network in the brain is believed to make us unique individuals. Electron microscopy is a valuable tool for examining ultrastructural characteristics of neurons, synapses, and subcellular organelles. A recent technological breakthrough in volume electron microscopy allows large-scale circuit reconstruction of the nervous system with unprecedented detail. Serial-section electron microscopy-previously the domain of specialists-became automated with the advent of innovative systems such as the focused ion beam and serial block-face scanning electron microscopes and the automated tape-collecting ultramicrotome. Further advances in microscopic design and instrumentation are also available, which allow the reconstruction of unprecedentedly large volumes of brain tissue at high speed. The recent introduction of correlative light and electron microscopy will help to identify specific neural circuits associated with behavioral characteristics and revolutionize our understanding of how the brain works.

• Applied Microscopy
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• v.47 no.1
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• pp.1-2
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• 2017

Professor Yoshinori Ohsumi received the 2016 Nobel Prize in Physiology or Medicine for his contribution to autophagy research, which was first studied using electron microscopy. To celebrate and commemorate this historical moment, I describe the role of electron microscopy in autophagy research and suggest a role for next-generation electron microscopy in this research field.

• Applied Microscopy
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• v.46 no.2
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• pp.100-104
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• 2016

Electron microscopy is currently the only available technique with a spatial resolution sufficient to identify fine neuronal processes and synaptic structures in densely packed neuropil. For large-scale volume reconstruction of neuronal connectivity, serial block-face scanning electron microscopy allows us to acquire thousands of serial images in an automated fashion and reconstruct neural circuits faster by reducing the alignment task. Here we introduce the whole reconstruction procedure of synaptic network in the rat hippocampal CA1 area and discuss technical issues to be resolved for improving image quality and segmentation. Compared to the serial section transmission electron microscopy, serial block-face scanning electron microscopy produced much reliable three-dimensional data sets and accelerated reconstruction by reducing the need of alignment and distortion adjustment. This approach will generate invaluable information on organizational features of our connectomes as well as diverse neurological disorders caused by synaptic impairments.

• Applied Microscopy
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• v.36 no.spc1
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• pp.1-7
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• 2006

The three-dimensional structure of an inorganic crystal, $SmZn_{0.67}Sb_2$ (space group $P4/nmm,\;a=4.30(3){\AA}\;and\;c= 10.27(1){\AA}$), was refined by electron crystallography utilizing high voltage electron microscopy (HVEM). Effects of instrumental resolution, image quality, beam damage and specimen tilting on the structure refinement have been evaluated. The instrumental resolution and image quality were the most important factors on the final results in the structure refinement, while the beam damage and specimen tilting effects could be experimentally minimized or controlled. The average phase errors $({\Phi}_{res})$ for the [001], [100] and [110] HVEM images of $SmZn_{0.67}Sb_2$ were $10.1^{\circ},\;9.6^{\circ}\;and\;6.8^{\circ}$, respectively. The atomic coordinates of $SmZn_{0.67}Sb_2$ were consistent within $0.0013{\AA}{\sim}0.0088{\AA}$, compared to the X-ray crystallography data for the same sample.

• Molecules and Cells
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• v.45 no.1
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• pp.41-50
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• 2022

The recently developed correlative super-resolution fluorescence microscopy (SRM) and electron microscopy (EM) is a hybrid technique that simultaneously obtains the spatial locations of specific molecules with SRM and the context of the cellular ultrastructure by EM. Although the combination of SRM and EM remains challenging owing to the incompatibility of samples prepared for these techniques, the increasing research attention on these methods has led to drastic improvements in their performances and resulted in wide applications. Here, we review the development of correlative SRM and EM (sCLEM) with a focus on the correlation of EM with different SRM techniques. We discuss the limitations of the integration of these two microscopy techniques and how these challenges can be addressed to improve the quality of correlative images. Finally, we address possible future improvements and advances in the continued development and wide application of sCLEM approaches.

• Applied Microscopy
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• v.8 no.1
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• pp.81-90
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• 1978

Introduction of electron microscope in biological and medical sciences change the concept of functional and morphologic unit of biological phenomena from the cell to subcellular unit, and it formulated the basis for molecular biology and pathology. Until recently, electron microscopy has mainly been applied to basic research works. However, practical clinical application of electron microscopy is being actively tried. The major clinical fields in which electron microscopy is helpful or even essential include viral diseases, metabolic diseases, glomerular diseases and in the identification of certain types of neoplasms. A brief introduction of characteristics of each conditions are made to encourage more active application of electron microscopy in clinical medicine.

• Applied Microscopy
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• v.45 no.4
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• pp.203-207
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• 2015

Sample preparation is very important for crystal structure analysis of novel nanostructured materials in electron microscopy. Generally, a grid dispersion method has been used as transmission electron microscope (TEM) sampling method of nano-powder samples. However, it is difficult to obtain the cross-sectional information for the tabular-structured materials. In order to solve this problem, we have attempted a new sample preparation method using focused ion beam. Base on this approach, it was possible to successfully obtain the electron diffraction patterns and high-resolution TEM images of the cross-section of tabular structure. Finally, we were able to obtain three-dimensional crystallographic information of novel zeolite nano-crystal of the tabular morphology by applying the new sample preparation technique.