scholarly journals ELECTRON MICROSCOPY OF BASOPHILIC STRUCTURES OF SOME INVERTEBRATE OOCYTES

1956 ◽  
Vol 2 (2) ◽  
pp. 159-170 ◽  
Author(s):  
Lionel I. Rebhun
Keyword(s):  
Electron Microscopy ◽  
Electron Microscope ◽  
Light Microscope ◽  
Entire Body ◽  
Spisula Solidissima ◽  
Hypothetical Model ◽  
Surf Clam

RNA containing yolk nuclei from the surf clam Spisula solidissima have been studied with the light microscope and with the electron microscope. A variety of structures can be seen with both and a correlation can be made between bodies studied with the electron microscope and those studied with the light microscope. The electron microscope shows many of these structures to be composed of double walled lamellae arranged in space, in various ways. The variety of patterns seen with the electron microscope can be satisfactorily explained on the basis of a hypothetical model. The presence of yolk platelets within the yolk nuclei lends support to classical observations on the synthesis of yolk within yolk nuclei or yolk nuclei derivatives. Small granules (about 100 A) are included within the double walled lamellae and their presence probably accounts for the basophilic nature of the entire body. The presence of small granules attached to electron-dense layers relates the yolk nuclei described here to ergastoplasm discussed by others.

scholarly journals AN ELECTRON MICROSCOPE STUDY OF THE EMBRYOLOGY OF THE INTERCALATED DISC IN THE HEART OF THE RABBIT

1957 ◽  
Vol 3 (2) ◽  
pp. 193-202 ◽  
Author(s):  
Alan R. Muir
Keyword(s):  
Electron Microscopy ◽  
Electron Microscope ◽  
Cardiac Muscle ◽  
Microscope Study ◽  
Light Microscope ◽  
Electron Microscope Study ◽  
Muscle Cells ◽  
Intercalated Disc ◽  
Adult Cell ◽  
Embryonic Muscle

Prenatal and postnatal cardiac muscle from rabbits has been studied by electron microscopy, after osmium fixation and methacrylate embedding. The observations showed that 1. Cell membranes divide the muscle into cellular units from the youngest embryo which was studied (9½ days after coitus) until the adult state. 2. The embryonic muscle cells contain only one nucleus, whereas the adult cell may be multinucleated. 3. At all stages of development, wherever a myofibrillar axis crosses a cellular boundary, the myofilaments are interrupted by an intercalated disc. 4. With age, increase in size and complexity of the discs render them recognisable by the light microscope.

scholarly journals Individual microtubules viewed by immunofluorescence and electron microscopy in the same PtK2 cell

1978 ◽  
Vol 77 (3) ◽  
pp. R27 ◽  
Author(s):  
M Osborn ◽  
RE Webster ◽  
K Weber
Keyword(s):  
Electron Microscopy ◽  
Electron Microscope ◽  
Light Microscope ◽  
Immunofluorescence Microscopy ◽  
Uranyl Acetate ◽  
Tubulin Antibodies ◽  
Ptk2 Cell ◽  
Cytoplasmic Microtubules ◽  
Triton X ◽  
Microtubular Structures

PtK2 cells were grown on gold grids and treated with Triton X-100 in a microtubule stabilizing buffer. The resulting cytoskeletons were fixed with glutaraldehyde and subjected to the indirect immunofluorescence procedure using monospecific tubulin antibodies. Grids were examined first by fluorescence microscopy, and the display of fluorescent cytoplasmic microtubules was recorded. The grids were then stained with uranyl acetate and the display of fibrous structures recorded by electron microscopy. Thus the display of cytoplasmic microtubular structures in the light microscope and the electron microscope can be compared within the same cytoskeleton. The results show a direct correspondence of the fluorescent fibers in the light microscope with uninterrupted fibers of diameter approximately 550 A in the electron microscope. This is the diameter reported for a single microtubule decorated around its circumference by two layers of antibody molecules. Thus under optimal conditions immunofluorescence microscopy can visualize individual microtubules.

scholarly journals Scanning Electron Microscopy Observations of Loa loa (Nematoda)

2020 ◽  
Vol 11 (2) ◽  
pp. 486-492
Author(s):  
Jens Anibal Juul ◽  
Vegard Asgeir Forsaa ◽  
Tor Paaske Utheim ◽  
Endre Willassen
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Electron Microscope ◽  
Case Report ◽  
Scanning Electron Microscope ◽  
Light Microscope ◽  
Loa Loa ◽  
Scanning Electron

We present a case report of periocular Loa loa. The key feature of L. loa distinguishing it from other human filarial parasites are cuticular bosses, which are presented in images from a light microscope and a scanning electron microscope. The cuticular bosses could be divided into three subtypes not previously described.

Bridging the Resolution Gap: Correlated 3D Light and Electron Microscopic Analysis of Large Biological Structures

1999 ◽  
Vol 5 (S2) ◽  
pp. 526-527
Author(s):  
Maryann E. Martone
Keyword(s):  
Electron Microscopy ◽  
Electron Microscope ◽  
Surface Area ◽  
Light Microscope ◽  
Microscopic Analysis ◽  
Electron Microscopic Analysis ◽  
Electron Microscopic ◽  
Transmission Electron ◽  
Biological Structures ◽  
Ganglion Neurons

One class of biological structures that has always presented special difficulties to scientists interested in quantitative analysis is comprised of extended structures that possess fine structural features. Examples of these structures include neuronal spiny dendrites and organelles such as the Golgi apparatus and endoplasmic reticulum. Such structures may extend 10's or even 100's of microns, a size range best visualized with the light microscope, yet possess fine structural detail on the order of nanometers that require the electron microscope to resolve. Quantitative information, such as surface area, volume and the micro-distribution of cellular constituents, is often required for the development of accurate structural models of cells and organelle systems and for assessing and characterizing changes due to experimental manipulation. Performing estimates of such quantities from light microscopic data can result in gross inaccuracies because the contribution to total morphometries of delicate features such as membrane undulations and excrescences can be quite significant. For example, in a recent study by Shoop et al, electron microscopic analysis of cultured chick ciliary ganglion neurons showed that spiny projections from the plasmalemma that were not well resolved in the light microscope effectively doubled the surface area of these neurons.While the resolution provided by the electron microscope has yet to be matched or replaced by light microscopic methods, one drawback of electron microscopic analysis has always been the relatively small sample size and limited 3D information that can be obtained from samples prepared for conventional transmission electron microscopy. Reconstruction from serial electron micrographs has provided one way to circumvent this latter problem, but remains one of the most technically demanding skills in electron microscopy. Another approach to 3D electron microscopic imaging is high voltage electron microscopy (HVEM). The greater accelerating voltages of HVEM's allows for the use of much thicker specimens than conventional transmission electron microscopes.

Mucilaginous film production by plant cells immobilised in a polyurethane or nylon matrix

1985 ◽  
Vol 63 (12) ◽  
pp. 2357-2363 ◽  
Author(s):  
M. J. C. Rhodes ◽  
R. J. Robins ◽  
R. J. Turner ◽  
J. I. Smith
Keyword(s):  
Thin Film ◽  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Light Microscope ◽  
Plant Cells ◽  
The Matrix ◽  
Nylon Fibre ◽  
Scanning Electron

The surface features of plant cells immobilised in a matrix of either reticulated polyurethane foam or nylon fibre have been examined with the scanning electron microscope. It has been found that both cells and matrix are enveloped in a thin film, the appearance of which is very dependent on the method by which material is prepared for scanning electron microscopy. The structure is severely damaged by fixation and dehydration. Only in specimens examined in the frozen hydrated state is a structure seen compatible with that observed with the light microscope. From the way the appearance of the film is affected by different methods of preparation for the scanning electron microscope, it is suggested that the film is a hydrated mucilage. The importance of this film for the retention of cells within the matrix is discussed.

scholarly journals ELECTRON MICROSCOPY OF THE AMMONIACAL SILVER REACTION FOR HISTONES IN THE ERYTHROPOIETIC CELLS OF THE CHICK

1970 ◽  
Vol 45 (2) ◽  
pp. 235-245 ◽  
Author(s):  
Edith K. MacRae ◽  
Gerald D. Meetz
Keyword(s):  
Electron Microscopy ◽  
Stem Cells ◽  
Bone Marrow ◽  
Electron Microscope ◽  
Light Microscope ◽  
Color Difference ◽  
Erythroid Cell ◽  
Erythroid Cells ◽  
Cell Series ◽  
Ammoniacal Silver

The product of the postformalin ammoniacal silver reaction, which has been claimed to distinguish lysine-rich from arginine-rich histones with the light microscope on the basis of a color difference, was examined in developing erythroid cells of chick bone marrow with the electron microscope. Stem cells and early erythroblasts exhibit no, or little, ammoniacal silver reaction product, while small basophilic erythroblasts, polychromatophilic erythrocytes, and reticulocytes exhibit an increasing amount of reaction product as maturation proceeds. The reaction product is in the form of discrete electron-opaque particles associated with heterochromatin. The ammoniacal silver reaction in the erythroid cell series is interpreted as reflecting either the accumulation of newly synthesized arginine-rich histones or changes in the availability of reactive sites in preformed histones.

Comparison of Larval Stored Product Beetle Mandibles by Light Microscope and Scanning Electron Microscope

1981 ◽  
Vol 64 (1) ◽  
pp. 199-224
Author(s):  
John E Kvenberg
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Light Microscopy ◽  
Light Microscope ◽  
Morphological Characteristics ◽  
Scanning Electron ◽  
Conventional Light Microscopy

Abstract Larval stored product beetle mandibles were studied by comparing images made by scanning electron microscopy with those made by conventional light microscopy. Discussion of morphological characteristics is based on illustrations of 25 species

XVIII.—The Spermatozoon of the Spider BeetlePtinus tectusBoieldieu as seen by Light and Electron Microscopy

1951 ◽  
Vol 64 (3) ◽  
pp. 353-366 ◽  
Author(s):  
Jozef Dlugosz ◽  
John W. Harrold
Keyword(s):  
Electron Microscopy ◽  
Electron Microscope ◽  
Light Microscope ◽  
Light And Electron Microscopy ◽  
Sperm Head ◽  
Central Axis

SynopsisThe mature Ptinid sperm examined under the light microscope is found to be specialised in that the chromatin is not contained within a sperm head but is distributed along a central axis. The migration of chromatin resembles that found in Coccids by Hughes-Schrader (1948). Surrounding the axis is a more flexible helical membrane extending the whole length of the sperm.Under the electron microscope the membrane appears to consist of eighteen or twenty thin fibres and two thick fibres with striated sheaths. Near the posterior end of the membrane the fibres are surrounded by a ring. The structure is simpler than that of mammalian and avian sperms examined by other workers with similar techniques. Under the electron microscope, stages in the migration of chromatin in the immature sperm show a number of discrete opaque bodies which may be chromosomes. The approximate dimensions of the various structures are given.

scholarly journals ELECTRON MICROSCOPY OF BASOPHILIC STRUCTURES OF SOME INVERTEBRATE OOCYTES

1956 ◽  
Vol 2 (1) ◽  
pp. 93-104 ◽  
Author(s):  
Lionel I. Rebhun
Keyword(s):  
Electron Microscopy ◽  
Electron Microscope ◽  
Nuclear Envelope ◽  
Cross Sections ◽  
Dense Material ◽  
Continuous Space ◽  
Surf Clam ◽  
Surface View ◽  
Hexagonal Pattern

Highly basophilic plate-shaped regions from oocytes of the surf clam have been examined with the electron microscope. The regions are composed of flat, hollow vesicles perforated by pores arranged, in surface view, in a hexagonal pattern. Cross-sections of this structure show a periodicity consisting of loops (cross-sections of the continuous space within the vesicle) alternating with spaces partly filled with dense material (pores). These structures are shown to resemble closely, the nuclear envelope. Similarities to and differences from basophilic regions of other cells are discussed and it is suggested that the small granules of Palade (38) are represented by granules composing the walls of the annuli of the nuclear envelope and assumed to be present in the annuli of the vesicles. Because of differences in the structure of these regions from basophilic regions of other cells, the name periodic lamellae is suggested since the structures show periodically repeating substructures (annuli) in both cross-sections and surface views.

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