scholarly journals Routine use of backscattered electron imaging to visualize cytochemical and autoradiographic reactions in semi-thin plastic sections.

1990 ◽  
Vol 38 (3) ◽  
pp. 403-414 ◽  
Author(s):  
A Nanci ◽  
S Zalzal ◽  
C E Smith
Keyword(s):  
Light Microscope ◽  
Cell Structure ◽  
Thin Sections ◽  
Backscattered Electron Imaging ◽  
Cell Compartments ◽  
Tissue Organization ◽  
Transmission Electron ◽  
Backscattered Electron ◽  
Thin Plastic ◽  
Electron Imaging

The scanning electron microscope (SEM) was used to examine cytochemical and autoradiographic reactions in 2-microns semi-thin sections of tissues conventionally fixed and embedded in various resins. The sections were examined using both the secondary and backscatter modes of the SEM at magnifications within the range attainable with the light microscope. Both modes allowed the imaging of phosphatase reaction product using cerium and lead capture, lectin-gold, and immunogold labeling, with and without silver enhancement, and autoradiography. Backscattered electron imaging (BEI), however, provided images with more contrast and structural details. This approach allows examination of large sections, with more contrast and resolution than the light microscope, and visualization of reactions not visible with this instrument. The improved imaging and the simple and conventional preparation of specimens indicate that BEI can be used routinely to examine tissue organization, cell structure, and the content of the various cell compartments with a resolution approaching that of transmission electron microscopy.

Correlative LM, SEM and TEM of argentaffin cells

1978 ◽  
Vol 36 (2) ◽  
pp. 84-85
Author(s):  
R.G. Frederickson ◽  
D.B. Spagnoli ◽  
P.B. DeNee
Keyword(s):  
Electron Microscopy ◽  
Secondary Electron ◽  
Thin Sections ◽  
Backscattered Electron Imaging ◽  
Selective Staining ◽  
Transmission Electron ◽  
Backscattered Electron ◽  
Electron Imaging ◽  
Different Levels ◽  
Tem Grid

The identification of small numbers of cells containing specific materials or having a particular location in a tissue can be observed cften in light microscopic (IM) sections by selective staining. In contrast, the same cells are often difficult to identify in alternate thin sections on grids by transmission electron microscopy (TEM). Grid bars produce periodic obstructions and consequently prevent the visualization of tissue continuity, making it difficult to identify landmarks. Also, the TEM image of a thin section of tissue does not correlate well with the thicker IM image. This is a matter of interpretation based on the different principles of image formation and the different levels of resolution.The purpose of this paper is to demonstrate a method which allows the same cells identified by IM to be more easily located in thin sections for TEM. This method combines the principles of backscattered electron imaging (BSI), secondary electron imaging (SEI) and heavy metal staining with scanning electron microscopy (SEM).

Application of Backscattered Electron Imaging to the Study of Scavenger Receptor-Mediated Endocytosis by Sinusoidal Cells in Bone Marrow

1985 ◽  
Vol 43 ◽  
pp. 542-545
Author(s):  
R.P. Becker ◽  
J.S. Geoffroy
Keyword(s):  
Bone Marrow ◽  
Endothelial Cells ◽  
Coated Pits ◽  
Thin Sections ◽  
Backscattered Electron Imaging ◽  
Sinusoidal Cells ◽  
Dense Bodies ◽  
Sinusoidal Cell ◽  
Backscattered Electron ◽  
Electron Imaging

The endothelial cells lining the postcapillary venous sinuses (sinusoids) in bone marrow take up colloidal gold-bovine serum albumin (BSA-Au) conjugates by means of a pathway involving coated pits and vesicles. Endocytosis of BSA- Au by these sinusoidal endothelial cells (sinusoidal cells) is rapid. Within one minute of pulse presentation (5 sec; intraaortic injection) with BSA-Au the probe is internalized and processed through pleomorphic endosomes to dense bodies known to be secondary lysosomes. By this time, 17% of the sinusoidal cell related BSA-Au is associated with the surface, while 83% is internalized, of which 2% is present in lysosomes. By four minutes, less than 8% of the observed BSA-Au is not internalized, the bulk being present predominantly in large pleomorphic vacuoles and dense bodies.That the endocytic process involves coated pits and vesicles prompts the suggestion that it may be receptor mediated. In order to investigate this possibility, biochemical and morphological studies were performed to determine the specificity and saturability of the putative receptor. Morphological analysis of TEM thin sections was aided by viewing large areas of the luminal sinusoidal cell surface in secondary electron (SEI) and backscattered electron imaging (BEI) modes of the scanning electron microscope.

The Use of Backscattered Electron Imaging and Transmission Electron Microscopy to Assess Bone Architecture and Mineral Loci: Effect of Intermittent Slow-Release Sodium Fluoride Therapy

1996 ◽  
Vol 2 (2) ◽  
pp. 79-86 ◽  
Author(s):  
Joseph E. Zerwekh ◽  
Dennis Bellotto ◽  
Kenneth S. Prostak ◽  
Herbert K. Hagler ◽  
Charles Y.C. Pak
Keyword(s):  
Electron Microscopy ◽  
Slow Release ◽  
Normal Subjects ◽  
Bone Architecture ◽  
Backscattered Electron Imaging ◽  
Transmission Electron ◽  
Mineral Deposition ◽  
Mineralization Defect ◽  
Backscattered Electron ◽  
Electron Imaging

Backscattered electron imaging (BEI) and transmission electron microscopy (TEM) were used to examine the effects of treatment with intermittent slow-release sodium fluoride (SRNaF) and continuous calcium citrate on bone architecture and crystallinity. Examination was performed in nondecalcified biopsies obtained from patients following up to four years of therapy (placebo or SRNaF) and compared to pretreatment biopsies from each patient, as well as to bone from young, normal subjects. BEI images disclosed increased areas of recent bone formation following fluoride administration. There was no evidence of a mineralization defect in any biopsy and both cortical and trabecular architecture remained normal. TEM analysis demonstrated intrafibrillar platelike crystals and extrafibrillar needlelike crystals for both the pre- and post-treatment biopsies as well as for the bone from young normal subjects. There was no evidence of increased crystal size or of an increase in extrafibrillar mineral deposition. These observations suggest that intermittent SRNaF and continuous calcium therapy exerts an anabolic action on the skeleton not accompanied by a mineralization defect or an alteration of bone mineral deposition. The use of BEI and TEM holds promise for the study of the pathophysiology and treatment of metabolic bone diseases.

High-Energy Backscattered Electron Imaging of Voids in Aluminum Metallizations

1991 ◽  
Vol 225 ◽  
Author(s):  
D. M. Follstaedt ◽  
J. A. Van Den Avyle ◽  
A. D. Romig ◽  
J. A. Knapp
Keyword(s):  
Void Formation ◽  
High Energy ◽  
Backscattered Electron Imaging ◽  
Transmission Electron ◽  
Scanning Transmission ◽  
Backscattered Electron ◽  
Electron Microscopes ◽  
Al Metallization ◽  
Electron Imaging ◽  
Scanning Electron Microscopes

ABSTRACTBackscattered electron imaging of microcircuits in scanning transmission electron microscopes at 120 kV is shown to produce improved images of voids in passivated Al metallization lines relative to those obtained with scanning electron microscopes at ≤ 40 kV. At 120 kV, resolutions of about 0.1 μm are achieved for voids imaged beneath 1.0 μm glass overlayers. This technique allows improved characterization of microstructures for basic investigations of void formation and more accurate counting of voids in microcircuits without removing glass overlayers. Smaller voids should also be detectable with the higher voltage.

Quantification of cell-surface expressed antigenic sites with 5-nm gold markers: Getting close to biologically relevant data

1989 ◽  
Vol 47 ◽  
pp. 1050-1051
Author(s):  
Etienne de Harven ◽  
Hilary Christensen ◽  
Richard Leung ◽  
Cameron Ackerley
Keyword(s):  
Cell Surface ◽  
Human Peripheral Blood ◽  
Contour Length ◽  
Thin Sections ◽  
Gold Particles ◽  
Biologically Relevant ◽  
Transmission Electron ◽  
Entire Cell ◽  
Electron Imaging ◽  
Cell Contour

The T-derived subset of human peripheral blood normal lymphocytes has been selected as a model system to study the usefulness of 5 nm gold markers for quantification of single epitopes expressed on cell surfaces. The chosen epitopes are parts of the CD3 and CD5 molecules and can be specifically identified by hybridoma produced monoclonal antibodies (MoAbs; LEU-4 and LEU-1; Becton-Dick- inson, Mountain view, CA) . An indirect immunolabeling procedure, with goat anti-murine IgG adsorbed on the surface of 5 nm colloidal gold particles (GAM-G5, Janssen Pharmaceutica, Beerse, Belgium) has been used. Backscattered Electron Imaging (BEI) in a field emission scanning electronmicroscope (SEM) and transmission electron microscopy of thin sections of lymphocytes labeled before plastic embedding, were both used to identify and quantitate gold labeled cell surface sites, Estimating that the thickness of “silver” sections is approximately 60 nm and counting the number of gold particles on the entire cell perimeter, we calculated that, for LEU-4, the number of markers per um2 of cell surface is in the 140-160 range (Fig.l). Cell contour length measurements indicated that the surface of one lymphocyte is approximately 130-160 um2 that of a smooth sphere of identical diameter, reflecting the role of microvilli in expanding the surface area. The total number of gold labeled sites on the surface of one lymphocyte averages, therefore between 20,000 and 24,000 per cell.

High-sensitivity detection of gold labels by high-angle dark-field STEM imaging

1990 ◽  
Vol 48 (3) ◽  
pp. 892-893 ◽  
Author(s):  
Max T. Otten
Keyword(s):  
High Sensitivity ◽  
Dark Field ◽  
Bright Field ◽  
Backscattered Electron Imaging ◽  
Backscattered Electrons ◽  
Average Atomic Number ◽  
Highly Sensitive ◽  
Backscattered Electron ◽  
Electron Imaging ◽  
High Sensitivity Detection

Labelling of antibodies with small gold probes is a highly sensitive technique for detecting specific molecules in biological tissue. Larger gold probes are usually well visible in TEM or STEM Bright-Field images of unstained specimens. In stained specimens, however, the contrast of the stain is frequently the same as that of the gold labels, making it virtually impossible to identify the labels, especially when smaller gold labels are used to increase the sensitivity of the immunolabelling technique. TEM or STEM Dark-Field images fare no better (Figs. 1a and 2a), again because of the absence of a clear contrast difference between gold labels and stain.Potentially much more useful is backscattered-electron imaging, since this will show differences in average atomic number which are sufficiently large between the metallic gold and the stains normally used. However, for the thin specimens and at high accelerating voltages of the STEM, the yield of backscattered electrons is very small, resulting in a very weak signal. Consequently, the backscattered-electron signal is often too noisy for detecting small labels, even for large spot sizes.

Enzyme histochemical application and backscattered electron imaging to visualize the distribution of lymphatic capillaries

1990 ◽  
Vol 48 (3) ◽  
pp. 880-881
Author(s):  
Seiji Kato
Keyword(s):  
Staining Method ◽  
Double Staining ◽  
Reaction Products ◽  
Blood Capillaries ◽  
Backscattered Electron Imaging ◽  
Histochemical Observation ◽  
Backscattered Electron ◽  
Double Staining Method ◽  
Electron Imaging ◽  
Cryostat Sections

Previously, the author repeatedly confirmed the higher 5’-nucleotidase (5’-Nase) and lower alkaline phoaphatase (ALPase) activities in the wall of lymphatic capillaries reacted with the lead-based method relative to those of blood capillaries. The ALPase, on the other hand, is markedly higher in blood capillaries than in lymphatics. On the basis of these enzyme characteristics, the author has developed a 5’-Nase— ALPase double staining method to differentiate small lymphatics from blood capillaries at the level of the light microcsopy. Furthermore, we applied it to histochemical observation of the lead-containing reaction products of 5’-Nase in lymphatics on the same or adjacent cryostat sections using backscattered electron imaging (BEI) in scanning electron microscope (SEM). This paper presents a new applicability of 5’-Nase histochemistry by BEI-SEM to demonstrate the distribution of lymphatic capillaries in tissue blocks.

Sign in / Sign up

Export Citation Format

Share Document