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

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.

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

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100127372 ◽

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.

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The Sarcoplasmic Reticulum of Frog Slow and Twitch Muscle Fibers as Revealed by Stereoscopic High Voltage Electron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100116383 ◽

1975 ◽

Vol 33 ◽

pp. 552-553 ◽

Cited By ~ 1

Author(s):

Craig H. Bailey ◽

Lee D. Peachey

Keyword(s):

Electron Microscopy ◽

Sarcoplasmic Reticulum ◽

High Voltage ◽

Muscle Fibers ◽

Three Dimensional ◽

Tissue Slices ◽

High Voltage Electron Microscopy ◽

Thin Sections ◽

Voltage Electron ◽

High Voltage Electron

Our present understanding of the distribution and morphology of the sarcoplasmic reticulum (SR) in frog slow and twitch muscle fibers has been derived largely from the examination of thin sections by electron microscopy. This conventional approach to the study of an organelle as complex as the SR is limited to a degree by section thickness, and the extraction of three-dimensional information must usually be gathered from an extensive collection of two-dimensional images. The present study represents an alternative approach to the problem of investigating the three-dimensional organization of the SR by utilizing high voltage electron microscopy (HVEM) and examining stereoscopic images of selectively stained 1.0 /μm thick slices of muscle tissue.Slow and twitch fibers from the distal fiber bundles of the frog (Rana pipiens) cruralis muscle were processed for electron microscopy according to the selective SR staining technique (DAB-H2O2 and Os-ferrocyanide) developed by Waugh. Tissue slices from 0.25 to 1.0 μm in thickness were cut on a diamond knife, mounted on grids either with or without plastic support films, and examined using the JEM-1000 microscope at the University of Colorado operating at an accelerating voltage of 1000 kV.

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Three-Dimensional Visualization of the T-System of Frog Muscle Using High Voltage Electron Microscopy and a Lanthanum Stain

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100080286 ◽

1977 ◽

Vol 35 ◽

pp. 570-571 ◽

Cited By ~ 2

Author(s):

Lee D. Peachey ◽

Clara Franzini-Armstrong

Keyword(s):

Electron Microscopy ◽

High Voltage ◽

Three Dimensional ◽

Biological Tissues ◽

High Voltage Electron Microscopy ◽

Transverse Tubular System ◽

Peroxidase Reaction ◽

Voltage Electron ◽

High Voltage Electron ◽

T System

The effective study of biological tissues in thick slices of embedded material by high voltage electron microscopy (HVEM) requires highly selective staining of those structures to be visualized so that they are not hidden or obscured by other structures in the image. A tilt pair of micrographs with subsequent stereoscopic viewing can be an important aid in three-dimensional visualization of these images, once an appropriate stain has been found. The peroxidase reaction has been used for this purpose in visualizing the T-system (transverse tubular system) of frog skeletal muscle by HVEM (1). We have found infiltration with lanthanum hydroxide to be particularly useful for three-dimensional visualization of certain aspects of the structure of the T- system in skeletal muscles of the frog. Specifically, lanthanum more completely fills the lumen of the tubules and is denser than the peroxidase reaction product.

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High-voltage electron microscopy of maxillary gland of spirochete-infected brine shrimp: lesion of efferent tubule

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100103875 ◽

1988 ◽

Vol 46 ◽

pp. 362-363

Author(s):

G. E. Tyson ◽

M. J. Song

Keyword(s):

Electron Microscopy ◽

High Voltage ◽

Brine Shrimp ◽

Natural Populations ◽

Three Dimensional ◽

Dimensional Structure ◽

High Voltage Electron Microscopy ◽

Voltage Electron ◽

High Voltage Electron ◽

Infected Adult

Natural populations of the brine shrimp, Artemia, may possess spirochete- infected animals in low numbers. The ultrastructure of Artemia's spirochete has been described by conventional transmission electron microscopy. In infected shrimp, spirochetal cells were abundant in the blood and also occurred intra- and extracellularly in the three organs examined, i.e. the maxillary gland (segmental excretory organ), the integument, and certain muscles The efferent-tubule region of the maxillary gland possessed a distinctive lesion comprised of a group of spirochetes, together with numerous small vesicles, situated in a cave-like indentation of the base of the tubule epithelium. in some instances the basal lamina at a lesion site was clearly discontinuous. High-voltage electron microscopy has now been used to study lesions of the efferent tubule, with the aim of understanding better their three-dimensional structure.Tissue from one maxillary gland of an infected, adult, female brine shrimp was used for HVEM study.

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

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100095571 ◽

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.

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