scholarly journals Immuno-electron-microscopic studies on the subcellular distribution of rat liver epoxide hydrolase and the effect of phenobarbitone and 2-acetamidofluorene treatment

1982 ◽  
Vol 202 (3) ◽  
pp. 677-686 ◽  
Author(s):  
F Waechter ◽  
P Bentley ◽  
M Germann ◽  
F Oesch ◽  
W Stäubli
Keyword(s):  
Electron Microscopy ◽  
Rat Liver ◽  
Subcellular Distribution ◽  
Epoxide Hydrolase ◽  
Specific Binding ◽  
Subcellular Fractions ◽  
Electron Microscopic ◽  
Immuno Electron Microscopy ◽  
Microscopic Studies ◽  
The Individual

The distribution of rat liver epoxide hydrolase in various subcellular fractions was investigated by immuno-electron-microscopy. Ferritin-linked monospecific anti-(epoxide hydrolase) immunoglobulins bound specifically to the cytoplasmic surfaces of total microsomal preparations and smooth and rough microsomal fractions as well as the nuclear envelope. Specific binding was not observed when the ferritin conjugates were incubated with peroxisomes, lysosomes and mitochondria. The average specific ferritin load of the individual subcellular fractions correlated well with the measured epoxide hydrolase activities. This correlation was observed with fractions prepared from control, phenobarbitone-treated and 2-acetamidofluorene-treated rats.

Characterization of Electrophoretic Lipoprotein Fractions: Immunochemical and Electron Microscopic Studies

1972 ◽  
Vol 18 (6) ◽  
pp. 534-538
Author(s):  
Mario Werner ◽  
Albert L Jones
Keyword(s):  
Electron Microscopy ◽  
Particle Size ◽  
Electrophoretic Pattern ◽  
Electron Microscopic ◽  
Lipoprotein Subfractions ◽  
New Techniques ◽  
Microscopic Studies ◽  
Insight Into

Abstract To improve the characterization of electrophoretic lipoprotein subfractions, we developed two new techniques for analyzing lipoproteins after electrophoresis on thin agarose layers. Overlay with antisera exactly localizes specific apoproteins without any distortion caused by antigen diffusion; electron microscopy of eluted fractions determines the varying particle-size distribution. Applied together, these methods can detect individual differences between hyperlipemic samples that are not immediately apparent in the electrophoretic pattern, and should provide valuable new insight into the classification of hyperlipoproteinemias.

scholarly journals EFFECT OF ACTIVE ACCUMULATION OF CALCIUM AND PHOSPHATE IONS ON THE STRUCTURE OF RAT LIVER MITOCHONDRIA

1964 ◽  
Vol 23 (1) ◽  
pp. 21-38 ◽  
Author(s):  
John W. Greenawalt ◽  
Carlo S. Rossi ◽  
Albert L. Lehninger
Keyword(s):  
Specific Gravity ◽  
Rat Liver ◽  
Cesium Chloride ◽  
Liver Mitochondria ◽  
Rat Liver Mitochondria ◽  
Electron Microscopic ◽  
Dense Granules ◽  
Phosphate Ions ◽  
Microscopic Studies

Rat liver mitochondria allowed to accumulate maximal amounts of Ca++ and HPO4= ions from the suspending medium in vitro during respiration have a considerably higher specific gravity than normal mitochondria and may be easily separated from the latter by isopycnic centrifugation in density gradients of sucrose or cesium chloride. When the mitochondria are allowed to accumulate less than maximal amounts of Ca++ and HPO4= from the medium, they have intermediate specific gravities which are roughly proportional to their content of calcium phosphate. Maximally "loaded" mitochondria are relatively homogeneous with respect to specific gravity. Correlated biochemical and electron microscopic studies show that Ca++-loaded mitochondria contain numerous dense granules, of which some 85 per cent are over 500 A in diameter. These granules are electron-opaque not only following fixation and staining with heavy metal reagents, but also following fixation with formaldehyde, demonstrating that the characteristic granules in Ca++-loaded mitochondria have intrinsic electron-opacity. The dense granules are almost always located within the inner compartment of the mitochondria and not in the space between the inner and outer membranes. They are frequently located at or near the cristae and they often show electron-transparent "cores." Such granules appear to be made up of clusters of smaller dense particles, but preliminary x-ray diffraction analysis and electron diffraction studies have revealed no evidence of crystallinity in the deposits. The electron-opaque granules decrease in number when the Ca++-loaded mitochondria are incubated with 2,4-dinitrophenol; simultaneously there is discharge of Ca++ and phosphate from the mitochondria into the medium.

The Ultrastructure of Crystalliferous Cells in Some Lecythidaceae With a Discussion of Their Terminology

IAWA Journal ◽  
1984 ◽  
Vol 5 (3) ◽  
pp. 229-236 ◽  
Author(s):  
N. Parameswaran ◽  
H.-G. Richter
Keyword(s):  
Electron Microscopic ◽  
Axial Parenchyma ◽  
Individual Crystal ◽  
Microscopic Studies ◽  
Per Se ◽  
The Individual

On the basis of a light microscopic c1assification of the genera of the Lecythidaceae according to the presence of crystalliferous cells in the axial wood parenchyma an attempt was made to characterise these cells at the fine structurallevel. Electron microscopic studies of the genera Allantoma, Grias and Gustavia revealed normal cross walls, as well as septumIike walls separating the individual crystal-containing units in the axial parenchyma strand. Based on these findings the terminology of the crystalliferous cells per se is discussed at some length.

Problems in Myogenesis Terminology in Electron Microscopy

1967 ◽  
Vol 25 ◽  
pp. 38-39
Author(s):  
P.E. Conen ◽  
J.U. Balis ◽  
C.D. Bell
Keyword(s):  
Electron Microscopy ◽  
Cell Types ◽  
Uranyl Acetate ◽  
Electron Microscopic ◽  
Accurate Identification ◽  
Microscopic Studies ◽  
A Cell ◽  
Lead Hydroxide ◽  
Developing Muscle

Myogenesis in man was studied using muscle from 19 fetuses of 8 to 16 weeks gestation which were processed with standard osmium-Epon or glutaraldehyde-osmium-Epon schedules and sections were stained in uranyl acetate and/or lead hydroxide. Particular emphasis was given during this study to presence of basement membrane and myofilaments as additional aids in classification of cell types present in developing muscle.Electron microscopy permits accurate identification of fibroblasts and early cells of muscle series and has been used in studies of myogenesis in chick, and rat. Light microscopy definitions for premyoblasts and myoblasts, and for myocytes at the myotube and muscle fiber stages of development are difficult to apply to electron microscopic studies without modification. For example the term myoblast was used differently by Tello, Katznelson and Boyd to designate a cell destined to become muscle but not recognizable as a muscle cell.

High-Resolution SEM of Colloidal Gold Labels

1988 ◽  
Vol 46 ◽  
pp. 214-217
Author(s):  
Ralph M. Albrecht ◽  
Scott R. Simmons ◽  
James R. Prudent ◽  
Chris M. Erickson
Keyword(s):  
Electron Microscopy ◽  
Colloidal Gold ◽  
Spherical Shape ◽  
Biologically Active ◽  
Electron Microscopic ◽  
Transmission Electron ◽  
Color Density ◽  
Microscopic Studies ◽  
Backscattered Electron ◽  
Electron Imaging

Colloidal gold, conjugated to a number of biologically active molecules, including ligand and antibody, provides a useful label for light microscopy and electron microscopy. This stems, in part, from its color, density, and regular spherical shape although the ability to make the particles in a number of defined sizes, the ease of conjugation to biological material, and the retention of activity of bound molecules are also important factors.Although nearly all sizes of colloidal gold particles, from 2.0 nm on up, can be identified in transmission or high voltage transmission electron microscopy, it has generally been the larger sized particles, 15 nm and up, that have proved useful for scanning electron microscopic studies. This is due principally to the resolution limits of conventional SEMs and the need to employ backscattered electron imaging, BEI, to unambiguously define the gold labels.

Ultrastructural and Scanning Electron Microscopic Studies of Basal Cell Carcinoma

1980 ◽  
Vol 38 ◽  
pp. 728-729
Author(s):  
A. Lupulescu
Keyword(s):  
Electron Microscopy ◽  
Basal Cell Carcinoma ◽  
Cell Carcinoma ◽  
Basal Cell ◽  
Basal Cells ◽  
Electron Microscopic ◽  
Transmission Electron ◽  
Microscopic Studies ◽  
And Migration ◽  
Scanning Electron

Previously it has been shown that long-term topical application of 3-methylcholanthrene (MCA) on the rat skin induced basal cell carcinoma. These tumors are very similar to that occurring in humans and they were studied only by light microscopy.1 Transmission electron microscopy (TEM) and Scanning electron microscopy (SEM) can provide more characteristic details for the neoplastic transformation of basal cells, their cytoarchitecture and migration.

Electron microscopy of spermatocytes previously studied in life: methods and some observations on micromanipulated chromosomes

1979 ◽  
Vol 35 (1) ◽  
pp. 87-104
Author(s):  
R.B. Nicklas ◽  
B.R. Brinkley ◽  
D.A. Pepper ◽  
D.F. Kubai ◽  
G.K. Rickards
Keyword(s):  
Electron Microscopy ◽  
Electron Microscope ◽  
Target Cell ◽  
Living Cell ◽  
Chromosome Movement ◽  
Electron Microscopic ◽  
Microscopic Studies ◽  
Direction Of Movement ◽  
Spindle Microtubules ◽  
Future Work

A new method is offered for combined living cell and electron-microscopic studies of spermatocytes (or other cells) which normally do not adhere to glass. The key step is micro-injection of glutaraldehyde near the target cell whenever desired during observation in life. Fixation begins and simultaneously the cell is stuck very firmly to the underlying coverslip. The method is easy and reliable: cells are almost never lost and are well preserved, except for membranes. The application of the method is illustrated by studies of micromanipulated grasshopper spermatocytes. A chromosome was detached from the spindle and placed in the cytoplasm. Before or after the beginning of chromosome movement back toward the spindle, the cell was fixed, sectioned and the manipulated chromosome observed in the electron microscope. If the detached chromosome had not moved by the time of fixation, no or only one or two microtubules were seen at its kinetochore, but if movement had occurred, a few microtubules were always present. The arrangement of these microtubules corresponded to the direction of movement, but they commonly were at an unusual angle relative to the kinetochore. The origin and role in chromosome movement of the microtubules seen near moving chromosomes far from the spindle is not yet established, but a speculation is offered. A goal for future work is the detailed analysis of the microtubules associated with individual moving chromosomes. Such an analysis is feasible because the moving chromosome is far removed from the confusing mass of spindle microtubules, and its value is enhanced because the direction of movement at the time of fixation is known.

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