High-voltage electron microscopic studies of inflammatory cell attachment during blood-brain barrier inflammation

1990 ◽  
Vol 48 (3) ◽  
pp. 276-277
Author(s):  
A.S. Lossinsky ◽  
M.J. Song
Keyword(s):  
High Voltage ◽  
Inflammatory Cell ◽  
Cell Attachment ◽  
Electron Microscopic ◽  
Vascular Perfusion ◽  
Tissue Samples ◽  
High Voltage Electron Microscopy ◽  
Thin Sections ◽  
Voltage Electron ◽  
High Voltage Electron

Previous studies have suggested the usefulness of high-voltage electron microscopy (HVEM) for investigating blood-bram barrier (BBB) injury and the mechanism of inflammatory-cell (IC) attachment. These studies indicated that, in evaluating standard conventional thin sections, one might miss cellular attachment sites of ICs in their process of attaching to the luminal endothelial cell (EC) surface of cerebral blood vessels. Our current studies in animals subjected to autoimmune disease suggest that HVEM may be useful in localizing precise receptor sites involved in early IC attachment.Experimental autoimmune encephalomyelitis (EAE) was induced in mice and rats according to standard procedures. Tissue samples from cerebellum, thalamus or spinal cords were embedded in plastic following vascular perfusion with buffered aldehyde. Thick (0.5-0.7 μm) sections were cut on glass knives and collected on Formvar-coated slot grids stained with uranylacetate and lead citrate and examined with the AEI EM7 1.2 MV HVEM in Albany, NY at 1000 kV.

High-voltage electron microscopic studies of the interrelationship between microglial cells and amyloid fibrils in scrapie-infected mouse brains

1991 ◽  
Vol 49 ◽  
pp. 86-87
Author(s):  
A. S. Lossinsky ◽  
M. J. Song ◽  
H. M. Wisniewski
Keyword(s):  
High Voltage ◽  
Cell Attachment ◽  
Microglial Cells ◽  
Stereo Pair ◽  
Amyloid Formation ◽  
Electron Microscopic ◽  
High Voltage Electron Microscopy ◽  
Voltage Electron ◽  
High Voltage Electron ◽  
Amyloid Deposits

We have previously demonstrated the usefulness of high-voltage electron microscopy (HVEM) in the study of microvessels and inflammatory cell attachment in the central nervous system (CNS). In the present study, we used HVEM to further explore the interrelationship between microglial cells (MCs) and amyloid deposits in scrapie-infected mice. Scrapie infection in the mouse has been employed as an animal model to study the pathogenesis of amyloid fibril formation. The central question was whether three-dimensional (3-D) stereo-pair reconstruction would offer further insight into amyloid formation by MCs, which is currently the view of our group. Brains or cervical spinal cords from IM mice previously inoculated with 87V scrapie agent were used. One-half-micrometer thick plastic sections were stained with uranyl acetate and lead citrate. Light-microscopy views enabled us to target primary inoculation channels associated with amyloid deposits. Cells located at the periphery of the amyloid were identified as MCs (Fig. 1).

On the High Voltage Electron Microscopy (1 MeV) of Biological Thick Sections

1972 ◽  
Vol 30 ◽  
pp. 464-465
Author(s):  
William H. Massover
Keyword(s):  
Electron Microscopy ◽  
High Voltage ◽  
Present Report ◽  
Biological Tissues ◽  
Specimen Preparation ◽  
Technical Problems ◽  
High Voltage Electron Microscopy ◽  
Thin Sections ◽  
Voltage Electron ◽  
High Voltage Electron

Stereoscopic examination of thick sections of fixed and embedded biological tissues by high voltage electron microscopy has been shown to allow direct visualization of three-dimensional fine structure. The present report will consider the occurrence of some new technical problems in specimen preparation and Image interpretation that are not common during lower voltage studies of thin sections.Thick Sectioning and Tissue Coloration - Epon sections of 0.5 μm or more that are cut with glass knives do not have a uniform thickness as Judged by their interference colors; these colors change with time during their flotation on the knife bath, and again when drying onto the specimen support. Quoted thicknesses thus must be considered only as rough estimates unless measured in specific regions by other methods. Chloroform vapors do not always result in good spreading of thick sections; however, they will spread spontaneously to large degrees after resting on the flotation bath for several minutes. Ribbons of thick sections have been almost impossible to obtain.

Three-Dimensional Analysis of Tranverse Tubules in Normal and Failing Heart: A Combined Confocal and High Voltage Electron Microscope Study

1997 ◽  
Vol 3 (S2) ◽  
pp. 231-232
Author(s):  
M. E. Martone ◽  
V. M. Edelman ◽  
A. Thor ◽  
S. J. Young ◽  
S. P. Lamont ◽  
...  
Keyword(s):  
High Voltage ◽  
Three Dimensional ◽  
Cardiac Cells ◽  
Electron Microscopic ◽  
High Voltage Electron Microscopy ◽  
Spontaneously Hypertensive ◽  
3 Dimensional ◽  
Voltage Electron ◽  
High Voltage Electron ◽  
T Tubules

Early electron microscopic studies documented that significant changes in the membrane systems of cardiac cells occur in both ischemic and non-ischemic heart failure. These studies relied on analysis of two-dimensional sections and although quantitative changes were observed, the overall organization of the tranverse tubules (T-tubules) and the sarcoplasmic reticulum could not be assessed. In a 3-dimensional study using high voltage electron microscopy (EM) of the T-tubules in spontaneously hypertensive rats, Nakamura and Hama (1991) observed that concomitant with an increase in surface area, the T-tubule system becomes progressively more disorganized and exhibits structural irregularities such as increased numbers of longitudinal tubules, numerous short dead end branches and complex tubular aggregates. These authors suggested that this disorganization may interfere with synchronous contraction over the entire cell.In the present study, we examined the 3-dimensional organization of T-tubules in the left ventricle of explanted human hearts using confocal microscopy and EM tomography.

scholarly journals The chondriome of selected trypanosomatids. A three-dimensional study based on serial thick sections and high voltage electron microscopy.

1975 ◽  
Vol 66 (2) ◽  
pp. 404-413 ◽  
Author(s):  
J J Paulin
Keyword(s):  
Electron Microscopy ◽  
High Voltage ◽  
Three Dimensional ◽  
Flagellar Pocket ◽  
High Voltage Electron Microscopy ◽  
Thin Sections ◽  
Voltage Electron ◽  
Trypomastigote Form ◽  
High Voltage Electron ◽  
Three Dimensional Models

The unitary nature of the chondriome of two species of trypanosomatids, Blastocrithidia culicis and Trypanosoma cruzi, has been demonstrated by utilizing serial thick-sectioning techniques combined with high voltage electron microscopy. Profiles of mitochondrial elements seen in thin sections and suspected to be parts of a continuum were confirmed by serial thick sectioning (0.25-0.50 mum thick) and stereopair analysis to be parts of the same mitochondrion. Three-dimensional models obtained from tracings of mitochondrial profiles on cellulose acetate reveal the mitochondrion of B. culicis to consist of a posterior mass with six tubular extensions extending upward and terminating in the anterior apex. The kinetoplast was found suspended between two of the tubular extensions, or less frequently, protuding as a nodule from one of the extensions. A bifurcation of one of the extensions was found in some specimens. The mitochondrion of T. cruzi consists of a triangular-shaped convoluted tubule, the base being the kinetoplast portion while the apex is directed posteriorly. The mitochondrion bifurcates behind the flagellar pocket, lateral to the kinetoplast, sending two entwined extensions into the tenuous anterior apex. Whether the mitochondrion of T. cruzi is unitary in the trypomastigote form was not determined in this study, since only epimastigote forms were used.

Observations on Developing Blood Vessels in Rat Spinal Cord—A High Voltage Electron Microscopy Study

1974 ◽  
Vol 32 ◽  
pp. 66-67
Author(s):  
Richard S. Hannah
Keyword(s):  
Electron Microscopy ◽  
Spinal Cord ◽  
High Voltage ◽  
Microscopy Study ◽  
Electron Microscopy Study ◽  
High Voltage Electron Microscopy ◽  
Thin Sections ◽  
Voltage Electron ◽  
High Voltage Electron ◽  
Transmission Electron

The formation of junctional complexes between endothelial cell processes was examined in rat spinal cords, from age birth to six weeks. Segments of spinal cord were removed from the region of the cervical enlargement and fixed. For comparative purposes, animals from each time group were subdivided into groups, fixed by either immersion or perfusion with an aldehyde combination in sodium cacodylate buffer and embedded in Araldite. Thin sections were examined by conventional transmission electron microscopy. Thick sections (0.5μ - 1.0μ) were stained with uranyl magnesium acetate for four hours at 60°C and lead citrate for 30 mins. and examined in the AEI Mark II High Voltage Electron Microscope.

High Voltage Electron Microscopy of Muscle

1969 ◽  
Vol 27 ◽  
pp. 96-97
Author(s):  
Robert V. Rice ◽  
J. S. Lally
Keyword(s):  
Electron Microscopy ◽  
Fine Structure ◽  
High Voltage ◽  
Striated Muscle ◽  
High Voltage Electron Microscopy ◽  
Thin Sections ◽  
Voltage Electron ◽  
High Voltage Electron ◽  
Cell Biol ◽  
Adjacent Structures

Several structures have been proposed to account for the appearance of Z and M-lines seen in thin sections of striated muscle. The high penetrating power of 800,000 to 1,000,000 volt electrons coupled with stereology offers a unique opportunity to resolve the complicated fine structure of Z and M-lines. In addition use has been made of the recently developed extraction and reconstitution of Z and M-lines (Stromer, Hartshorne, Mueller, and Rice, J. Cell Biol., 40, 167, 1969). Removal of portions of these structures helps to eliminate confusion due to adjacent structures.

Histo-grade diamond knives may be an appropriate tool for high-voltage electron microscopy

1991 ◽  
Vol 49 ◽  
pp. 296-297
Author(s):  
M.E. Rock ◽  
J.A. Anderson ◽  
P.S. Binder
Keyword(s):  
Electron Microscopy ◽  
High Voltage ◽  
Stereo Pair ◽  
Specimen Thickness ◽  
Serial Sections ◽  
High Voltage Electron Microscopy ◽  
Thin Sections ◽  
Voltage Electron ◽  
High Voltage Electron ◽  
Diamond Knife

High voltage electron microscopy (HVEM) has been employed in various ways (whole mounts of cells stereo pair imaging, axial tomography, and serial sections for reconstruction) to elucidate three dimensional (3-D) ultrastructural data. The increased specimen thickness allows further data analysis unobtainable from ultra-thin sections. HVEM can reduce the number of sections needed in 3-D reconstructiortby approximately ten times over conventional transmission electron microscopy (CTEM). But increasing section thickness also increases wear on the diamond knife used to section. We have compared the serial sections obtained from a histo-grade diamond knife with those from an E.M. grade ultra-knife. Both sets of sections were cut 0.5 μm thick from the same block, and evaluated under the one million volt beam of the HVEM.

The application of three-dimensional tomographic reconstruction methods to high-voltage electron microscopy

1987 ◽  
Vol 45 ◽  
pp. 570-573
Author(s):  
B. F. McEwen ◽  
C. L. Rieder ◽  
M. Radermacher ◽  
R. A. Grassucci ◽  
J. N. Turner ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
High Voltage ◽  
Three Dimensional ◽  
Depth Of Field ◽  
Specimen Thickness ◽  
High Voltage Electron Microscopy ◽  
Thin Sections ◽  
Voltage Electron ◽  
High Voltage Electron ◽  
Reconstruction Methods

High-voltage electron microscopy (HVEM) has considerably increased the thickness limit of biological specimens that can be visualized at high resolution. Because of its increased penetration power, HVEM is potentially the most powerful tool available for obtaining three-dimensional (3D) information concerning the structure of cells. In the past, such information was primarily obtained from serial thin sections or techniques based on surface shadowing, but these methods have severe problems and limitations which can only be overcome by imaging greater depths in the samples (see refs. 1 and 2). HVEM has yet to realize its potential for 3D structural determination because of the confusion arising from the overlap of features at different depths in the sample. Due to the relatively large depth of field, which exceeds the specimen thickness, HVEM (like all electron microscopy) produces an image that is essentially a projection of the sample.

Increasing Access to Tomographic Resources: Web-based Telemicroscopy and Database

2001 ◽  
Vol 7 (S2) ◽  
pp. 92-93
Author(s):  
M. E. Martone ◽  
S. Peltier ◽  
S. Lamont ◽  
A. Gupta ◽  
B. Ludaescher ◽  
...  
Keyword(s):  
Golgi Apparatus ◽  
High Voltage ◽  
Cell Biology ◽  
Electron Tomography ◽  
The United States ◽  
Electron Microscopic ◽  
Thin Sections ◽  
Voltage Electron ◽  
High Voltage Electron ◽  
Electron Microscopes

The application of electron tomography to cell biology has led to important insights into the 3D fine structure of subcellular processes and organelles. Tomography has been particularly useful for studying relatively large, multi-component structures such as the Golgi apparatus, mitochondria and synaptic complexes. When combined with very powerful high voltage electron microscopes, tomography has also provided high resolution quantitative views of extended structures such as neuronal dendrites in very thick sections (4 μm) at electron microscopic resolution. The utility of tomography is twofold: first, it provides 3D examination of subcellular structure without the need for serial section analysis; second, because the computed slices through the tomographic volumes can be much thinner than is possible to produce by physical sectioning, it reveals structural detail in the range of 5-30 nm that tends to be obscured in conventional thin sections. Tomographic analysis has forced re-assessment of long-standing views of organelles such as mitochondria and the Golgi apparatus and as the technique advances, additional insights are likely forthcoming.Electron tomography is an expensive technique, both in terms of the instruments used and the computational resources required. The three major high voltage electron microscope resources in the United States, San Diego, Boulder and Albany, all are actively engaged in tomographic research and offer this important technology to the scientific community at large.

Correlative confocal light microscopy and high-voltage electron microscopy of neurons

1992 ◽  
Vol 50 (1) ◽  
pp. 564-565
Author(s):  
J.N. Turner ◽  
D.H. Szarowski ◽  
D. Decker ◽  
K.L. Smith ◽  
M. Fejtl ◽  
...  
Keyword(s):  
Electron Microscope ◽  
High Voltage ◽  
Light Microscope ◽  
Brain Slices ◽  
Ultrastructural Level ◽  
Three Dimensions ◽  
Electron Microscopic ◽  
High Voltage Electron Microscopy ◽  
Voltage Electron ◽  
High Voltage Electron

Neurons are cells with extensive dendritic and axonal arborizations extending from the cell body hundreds of micrometers or more in all three-dimensions. These structures have specializations, such as dendritic spines, that are at or just below the level of resolution of the light microscope (LM), and others, such as synapses, that can be resolved only in the electron microscope. Thus, it can be essential to correlate light and electron microscopic images from the same specimen. Due to its discrimination along the z-dimension (optic axis), the confocal light microscope is ideal for investigating neurons and correlating their structure and function. At the ultrastructural level, we use the high-voltage electron microscope (HVEM) to collect three-dimensional data, because it images thick objects. We are studying neurons in culture, and in thick acute and long term cultured brain slices. LM observations are made either after fixation or live by LM, and these images are correlated with HVEM ultrastructural observations.

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