scholarly journals SPIRE, Surface Projection Image Recognition Environment for bicontinuous phases: application for plastid cubic membranes

2021 ◽  
Author(s):  
Tobias M. Hain ◽  
Michał K. Bykowski ◽  
Matthias Saba ◽  
Myfanwy E. Evans ◽  
Gerd E. Schröder-Turk ◽  
...  
Keyword(s):  
Diamond Surface ◽  
Structure Identification ◽  
Analysis Method ◽  
Cell Organelles ◽  
Robust Identification ◽  
Transmission Electron ◽  
Surface Models ◽  
Projection Image ◽  
Function Relationship ◽  
Bicontinuous Phases

AbstractBicontinuous membranes in cell organelles epitomise nature’s ability to create complex functional nanostructures. Like their synthetic counterparts, these membranes are characterised by continuous membrane sheets draped onto topologically complex saddle-shaped surfaces with a periodic network-like structure. In cell organelles, their structure sizes around 50–500 nm and fluid nature make Transmission Electron Microscopy (TEM) the analysis method of choice to decipher nanostructural features. Here we present a tool to identify bicontinuous structures from TEM sections by comparison to mathematical “nodal surface” models, including the hexagonal lonsdaleite geometry. Our approach, following pioneering work by Deng and Mieczkowski (1998), creates synthetic TEM images of known bicontinuous geometries for interactive structure identification. We apply the method to the inner membrane network in plant cell chloroplast precursors and achieve a robust identification of the bicontinuous diamond surface as the dominant geometry in several plant species. This represents an important step in understanding their as yet elusive structure-function relationship.

A simple technique for staining of cell membranes with imidazole and osmium tetroxide.

1995 ◽  
Vol 43 (10) ◽  
pp. 1079-1084 ◽  
Author(s):  
G Thiéry ◽  
J Bernier ◽  
M Bergeron
Keyword(s):  
Osmium Tetroxide ◽  
Cell Membranes ◽  
Cell Organelles ◽  
Unsaturated Lipids ◽  
Transmission Electron ◽  
Glutaraldehyde Solution ◽  
Kidney Liver ◽  
The Relationship ◽  
Resin Penetration

We describe a simple new technique based on the affinity of imidazole and osmium tetroxide for unsaturated lipids. Organs (e.g., kidney, liver, intestine) were perfused in vivo with a glutaraldehyde solution. Tissue fragments were then immersed in a solution containing imidazole and OsO4 and are further stained with a double lead and copper citrate solution. Ultra-thin (0.06 microns) or thick (0.1-0.3 microns) sections were observed with transmission electron microscopy (80-100 kV). The method presented permits excellent visualization of cell membranes (e.g., endoplasmic reticulum, endocytotic apparatus) because it favors good resin penetration and the alkaline pH preserves cell volume. A better stereomicroscopic analysis of the relationship between cell organelles can be carried out with thick sections. The imidazole/osmium can be used routinely because the technical steps are easy and simple to follow. Furthermore, it can complement other cytochemical methods.

Plasma membrane-associate filament systems in cultured cells visualized by dry-cleaving

1983 ◽  
Vol 64 (1) ◽  
pp. 351-364
Author(s):  
D.A. Mesland ◽  
H. Spiele
Keyword(s):  
Cultured Cells ◽  
Hepatoma Cell ◽  
Cell Types ◽  
Membrane Skeleton ◽  
Adhesive Tape ◽  
Cell Organelles ◽  
Red Cell Membrane ◽  
Transmission Electron ◽  
General Network ◽  
Dry Cleaving

Substrate-attached critical-point-dried cells cleave along the level of the substrate-adherent membrane if removed by means of adhesive tape. The remaining membrane fragments on grids can be visualized three-dimensionally by means of stereo transmission electron microscopy. Attachment of cells may be achieved by active spreading of the cell, or artificially by poly-L-lysine adherence of prefixed cells. In 11 different cell types a filamentous network appears to remain associated with the cytoplasmic face of the membrane. In one hepatoma cell type virtually no filamentous network could be detected. Two general network morphologies are described: the hepatocytic network and the lymphoid network. Since no correspondence could be found between cytoplasmic structure and the structure of the membrane-associated network, and since cells generally cleave along the level of this network, excluding cell organelles, we conclude that it comprises a distinct structural system, analogous to the membrane skeleton of the red cell membrane.

Effect of Size, Shape, Composition, and Support Film on Localized Surface Plasmon Resonance Frequency: A Single Particle Approach Applied to Silver Bipyramids and Gold and Silver Nanocubes

2009 ◽  
Vol 1208 ◽  
Author(s):  
Emilie Ringe ◽  
Jian Zhang ◽  
Mark R. Langille ◽  
Kwonnam Sohn ◽  
Claire Cobley ◽  
...  
Keyword(s):  
Surface Plasmon ◽  
Single Particle ◽  
Localized Surface Plasmon ◽  
Correlation Technique ◽  
Ensemble Averaging ◽  
Nanophotonic Devices ◽  
Silver Nanocubes ◽  
Transmission Electron ◽  
Function Relationship ◽  
Relationship Of

AbstractLocalized surface plasmon resonances (LSPR), collective electron oscillations in nanoparticles, are being heavily scrutinized for applications in chemical and biological sensing, as well as in prototype nanophotonic devices. This phenomenon exhibits an acute dependence on the particle’s size, shape, composition, and environment. The detailed characterization of the structure-function relationship of nanoparticles is obscured by ensemble averaging. Consequently, single-particle data must be obtained to extract useful information from polydisperse reaction mixtures. Recently, a correlated high resolution transmission electron microscopy (HRTEM) LSPR technique has been developed and applied to silver nanocubes. We report here a second generation of experiments using this correlation technique, in which statistical analysis is performed on a large number of single particles. The LSPR dependence on size, shape, material, and environment was probed using silver right bipyramids, silver cubes, and gold cubes. It was found that the slope of the dependence of LSPR peak on size for silver bipyramids increases as the edges become sharper. Also, a plasmon shift of 96 nm was observed between similar silver and gold cubes, while a shift of 26 nm was observed, for gold cubes, between substrates of refractive index (RI) of 1.5 and 2.05.

scholarly journals Inhibition of Estrogenic Response of Yeast Screen Assay by Exposure to Non-Lethal Levels of Metallic Nanoparticles

2020 ◽  
Vol 10 (11) ◽  
pp. 3796
Author(s):  
Byoung-cheun Lee ◽  
Cuong N. Duong ◽  
Jungkon Kim ◽  
Suejin Kim ◽  
Ig-chun Eom ◽  
...  
Keyword(s):  
Metallic Nanoparticles ◽  
Estrogenic Activity ◽  
Endocrine Disrupting Compounds ◽  
Cell Organelles ◽  
Yeast Saccharomyces Cerevisiae ◽  
Tem Analysis ◽  
Environmental Media ◽  
Transmission Electron ◽  
17Β Estradiol

In order to investigate the effects of metallic nanoparticles (NPs) on the performance of in vitro bioassay, zinc oxide NP (ZnO NP), aluminum oxide NP (Al2O3 NP), bare silver NP (Ag NP), and Ag NP capped with citrate (Agcit NP) were evaluated with yeast (Saccharomyces cerevisiae Y190) two-hybrid system (YES assay), carrying Japanese medaka estrogen receptors (mERs) in the presence of 17β-estradiol (E2, 10−6 M), a reference chemical for estrogenic activity. The distribution of NPs in the yeast was also examined by field-emission transmission electron microscopy (FE-TEM). The results show that TEM analysis revealed that NPs were present inside the yeast and accumulated deep inside the cell organelles, suggesting that cell death was caused by NPs. However, despite no significant change of mortality, the E2 estrogenic activities in yeast exposed to ZnO NP and Al2O3 NP were dose-dependently reduced. For Ag NP and Agcit NP, such phenomenon observed in the exposure of ZnO NP and Al2O3 NP did not occur. From the observations, we found that ZnO NP and Al2O3 NP in the environmental media could result in underestimated estrogenicity of endocrine-disrupting compounds when evaluated by YES assay.

Interrelations between the Parasitophorous Vacuole ofToxoplasma gondiiand Host Cell Organelles

2005 ◽  
Vol 11 (2) ◽  
pp. 166-174 ◽  
Author(s):  
Rodrigo Cardoso Magno ◽  
Lorian Cobra Straker ◽  
Wanderley de Souza ◽  
Marcia Attias
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Endoplasmic Reticulum ◽  
Host Cell ◽  
Fluorescent Probes ◽  
Parasitophorous Vacuole ◽  
Laser Scanning Microscopy ◽  
Cell Organelles ◽  
Apical Side ◽  
Transmission Electron

Toxoplasma gondii, the causative agent of toxoplasmosis, is capable of actively penetrating and multiplying in any nucleated cell of warm-blooded animals. Its survival strategies include escape from fusion of the parasitophorous vacuole with host cell lysosomes and rearrangement of host cell organelles in relation to the parasitophorous vacuole. In this article we report the rearrangement of host cell organelles and elements of the cytoskeleton of LLCMK2 cells, a lineage derived from green monkey kidney epithelial cells, in response to infection byT. gondiitachyzoites. Transmission electron microscopy made on flat embedded monolayers cut horizontally to the apical side of the cells or field emission scanning electron microscopy of monolayers scraped with scotch tape before sputtering showed that association of mitochondria to the vacuole is much less frequent than previously described. On the other hand, all parasitophorous vacuoles were surrounded by elements of the endoplasmic reticulum. These data were complemented by observations by laser scanning microscopy using fluorescent probes from mitochondria and endoplasmic reticulum and reinforced by three-dimensional reconstruction from serial sections observed by transmission electron microscopy and labeling of mitochondria and endoplasmic reticulum by fluorescent probes.

Fine structure of ocelli of the larval black fly Simulium vittatum (Diptera: Simuliidae)

1987 ◽  
Vol 65 (1) ◽  
pp. 142-150 ◽  
Author(s):  
Joyce M. Nyhof ◽  
Susan B. McIver
Keyword(s):  
Fine Structure ◽  
Polarized Light ◽  
Cell Organelles ◽  
Golgi Bodies ◽  
Simulium Vittatum ◽  
Pigment Granules ◽  
Transmission Electron ◽  
Structural Differences ◽  
Numerous Cell ◽  
Retinular Cells

The fine structure of light- and dark-adapted ocelli of last instar larval Simulium vittatum Zetterstedt was described using scanning and transmission electron microscopy. Larvae have six ocelli arranged in groups of three on each side of the head. The larger two ocelli of each group are externally visible as two darkly pigmented eyespots. The third, smaller ocellus lacks pigmentation and, therefore, is not externally visible. Each ocellus has its long axis oriented dorso-ventrally, has 13 retinular cells, and lacks an expanded cuticular lens. Conspicuous rhabdoms occur in the three ocelli. The rhabdoms of the pigmented ocelli are centrally located and enveloped by pigment granules. The microvilli of the rhabdoms are oriented primarily in one plane, an indication of a possible sensitivity to polarized light. The rhabdom of the unpigmented ocellus is eccentrically located and its microvilli are not uniplanar. Each ocellus has numerous cell organelles, including mitochondria, ribosomes, endoplasmic reticulum, and Golgi bodies. Especially conspicuous are membranous figures, which are associated with the nuclei and vary in size and complexity from simple stacks to lamellar whorls. These latter organelles are probably involved in the turnover processes of the rhabdomeric membranes. In light- and dark-adapted ocelli the only structural differences were associated with the microvilli and multivesicular bodies. Differences in location of pigment granules and in size of rhabdomeres and membranous figures were not observed.

scholarly journals MONITORING THE UPTAKE AND INTRACELLULAR FATE OF NANOVECTORS BY MICROSCOPICAL TECHNIQUES

2017 ◽  
Author(s):  
Manuela Costanzo ◽  
Flavia Carton ◽  
Manuela Malatesta
Keyword(s):  
Enzymatic Degradation ◽  
Cell Organelles ◽  
Uptake Mechanism ◽  
Trafficking Pathway ◽  
Transmission Electron ◽  
Target Sites ◽  
Confocal Fluorescence ◽  
Pass Through ◽  
Diagnostic Applications ◽  
Intracellular Fate

Nanovectors are receiving great attention for their potential in therapeutic and diagnostic applications as innovative systems for drug delivery and medical imaging. Their unique features allow them to pass through the biological barriers, to accumulate at the target sites, to protect the loaded drugs from enzymatic degradation and to modulate their release. To design effective and safe administration procedures of nanovectors it is obviously mandatory to assess their possible cytotoxicity, but it is also essential to elucidate the uptake mechanism(s), the intracellular trafficking pathway, the interactions with cell organelles and the intracellular persistence of nanovectors, paying particular attention to their degradation routes. Microscopy is especially suitable to describe the interaction of nanocarriers with the cell surface and their intracellular fate following internalization. Fluorochrome-labelled nanoparticles may be observed by conventional and confocal fluorescence microscopy, while the higher resolution of transmission electron microscopy allows to reveal the specific relationships of nanocomposites with the subcellular constituents. This work summarizes some studies performed by different microscopical techniques to evaluate the properties of nanoparticles intended for therapeutic and diagnostic purposes.

Transmission Electron Microscopy of Endometrium in Women Bearing Progesterone- Releasing Intrauterine Devices

1975 ◽  
Vol 33 ◽  
pp. 604-605
Author(s):  
A. González-Angulo ◽  
R. Aznar-Ramos ◽  
I. Ruiz de Chavez
Keyword(s):  
Release Rate ◽  
Ultrastructural Level ◽  
Intrauterine Devices ◽  
Cell Organelles ◽  
Continuous Release ◽  
Reduced Frequency ◽  
Transmission Electron ◽  
Proliferative Endometrium ◽  
Secretory Endometrium ◽  
Natural Progesterone

The addition of natural progesterone with a continuous daily release rate to inert intrauterine devices has resulted in a lower pregnancy rate and a reduced frequency of bleeding and expulsions. Light microscopy studies on these endometria have shown a suppressed or inactive pattern in addition to inflammatory infiltrate as well as a diffuse predecidual reaction with degenerative changes in most cases. The aim of the present study is to characterize at ultrastructural level the possible modifications seen in cell organelles in both epithelium and stroma resulting from a continuous release rate of progesterone.Twenty endometrial biopsies were taken; ten at day 10 ± 2 and ten at 20 ± 2 days of the menstrual cycle. Proliferative endometrium disclosed a paucity of cell organelles and it was similar to what has been described for inert devices (2). Secretory endometrium disclosed accumulation of light and dark glycogen in the cytoplasm (Fig. 1).

A Study of SRAM Device Soft Failures Caused by Contact Volcano Defects Using Nanoprobing Analysis

2011 ◽  
Author(s):  
Yu Hsiang Shu ◽  
Vincent Huang ◽  
Chia Hsing Chao
Keyword(s):  
Failure Analysis ◽  
High Resistance ◽  
Ion Beam ◽  
Analysis Method ◽  
Root Cause ◽  
Parametric Data ◽  
Transmission Electron ◽  
Focus Ion Beam ◽  
Electrical Data

Abstract Using nanoprobing techniques to accomplish transistor parametric data has been reported as a method of failure analysis in nanometer scale defect. In this paper, we focus on how to identify the influence of Contact high resistance on device soft failures using nanoprobing analysis, and showing that the equivalent mathematical models could be used to describe the corresponding electrical data in a device with Contact high resistance issue. A case study was presented to verify that Contact volcano defect caused Contact high resistance issue, and this issue can be identified via physical failure analysis (PFA) method (e.g. Transmission Electron Microscope and Focus Ion Beam techniques) and nanoprobing analysis method. Finally, we would explain the physical root cause of Contact volcano issue.

Comparative transmission electron microscopic studies on eosinophil of non ruminants

2016 ◽  
Author(s):  
S. Mehta ◽  
A. P. Minj
Keyword(s):  
Cell Organelles ◽  
Electron Microscopic ◽  
Double Membrane ◽  
Cytoplasmic Granules ◽  
Transmission Electron ◽  
Transmission Electron Microscopic ◽  
Microscopic Studies ◽  
Membrane Bound ◽  
Cytoplasmic Processes ◽  
Apparently Healthy

Transmission electron microscopic studies of eosinophil of horse, dog, pig and rabbit were carried out on six apparently healthy animals of each species. Ultrastructurally the eosinophils appeared round to oval in shape with few, short and narrow cytoplasmic processes in horse, oval with numerous long and wide cytoplasmic processes in dog and round with thin and broad small cytoplasmic processes in pig. While in rabbit it was round to oval in shape with long cytoplasmic processes. The nucleus had two to three lobes in all the animals. In all the four species it was observed that the heterochromatin was concentrated towards the periphery. Granules were mostly oval in outline and more or less similar in shape and size in horse while in dog the granules were rounded in shape and medium sized. In pig the double membrane bound cytoplasmic granules were roughly rounded to oval in shape and distributed throughout the cytoplasm. The granules in rabbit were mostly oval in outline and more or less similar in dimension. Cell organelles were clearly visible in the cytoplasm of horse while poorly visible in dog, pig and rabbit.

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