scholarly journals THE FINE STRUCTURE OF THE RAT CEREBELLUM

1964 ◽  
Vol 23 (2) ◽  
pp. 277-293 ◽  
Author(s):  
Robert M. Herndon
Keyword(s):  
Fine Structure ◽  
Electron Microscope ◽  
Light Microscope ◽  
Osmium Tetroxide ◽  
Granule Cells ◽  
Cell Types ◽  
Bergmann Glia ◽  
Rat Cerebellum

This paper describes the fine structure of the granule cells, stellate neurons, astrocytes, Bergmann glia, oligodendrocytes, and microglia of the rat cerebellum after fixation by perfusion with buffered 1 per cent osmium tetroxide. Criteria are given for differentiating the various cell types, and the findings are correlated with previous light microscope and electron microscope studies of the cerebellum.

Selective Staining of Acid Mucopolysaccharides By Ruthenium Red

1968 ◽  
Vol 26 ◽  
pp. 38-39
Author(s):  
J. H. Luft
Keyword(s):  
Electron Microscope ◽  
Light Microscopy ◽  
Light Microscope ◽  
Osmium Tetroxide ◽  
Single Cells ◽  
Ruthenium Red ◽  
Collagen Fibers ◽  
Selective Staining ◽  
Pectic Substances ◽  
Solid Tissues

Ruthenium red is one of the few completely inorganic dyes used to stain tissues for light microscopy. This novelty is enhanced by ignorance regarding its staining mechanism. However, its continued usefulness in botany for demonstrating pectic substances attests to selectivity of some sort. Whether understood or not, histochemists continue to be grateful for small favors.Ruthenium red can also be used with the electron microscope. If single cells are exposed to ruthenium red solution, sufficient mass can be bound to produce observable density in the electron microscope. Generally, this effect is not useful with solid tissues because the contrast is wasted on the damaged cells at the block surface, with little dye diffusing more than 25-50 μ into the interior. Although these traces of ruthenium red which penetrate between and around cells are visible in the light microscope, they produce negligible contrast in the electron microscope. However, its presence can be amplified by a reaction with osmium tetroxide, probably catalytically, to be easily visible by EM. Now the density is clearly seen to be extracellular and closely associated with collagen fibers (Fig. 1).

The Ultra-fine Structure of Lipid Globules in the Neurones of Helix aspersa

1958 ◽  
Vol s3-99 (46) ◽  
pp. 279-284
Author(s):  
J.T. Y. CHOU ◽  
G. A. MEEK
Keyword(s):  
Methylene Blue ◽  
Fine Structure ◽  
Electron Microscope ◽  
Electron Micrographs ◽  
Light Microscope ◽  
Helix Aspersa

The three kinds of lipid globules recognizable in the living neurones of Helix aspersa have been examined under the electron microscope. The globules of the kind that can be stained blue with methylene blue during life are seen in electron micrographs as spheres or spheroids, with concentric lamination, after calcium-osmium fixation. After fixation with sucrose-osmium laminated crescentic bodies are seen instead; these appear to be formed by distortion of the ‘blue’ globules. The yellow globules contain electrondense material, and sometimes appear reticular. It is possible that the yellow globules may originate by transformation of some of the ‘blue’ globules. The colourless globules generally appear as crenated objects; this appearance may be a shrinkage artifact. Apart from the mitochondria and the three kinds of lipid globules described, no other object large enough to be identified with the light microscope has been seen in the cytoplasm.

Lipid in Erysiphe graminis hordei and its possible role during germination

1970 ◽  
Vol 16 (11) ◽  
pp. 1041-1044 ◽  
Author(s):  
W. E. McKeen
Keyword(s):  
Fine Structure ◽  
Electron Microscope ◽  
Osmium Tetroxide ◽  
Erysiphe Graminis ◽  
Glutaraldehyde Fixation ◽  
Sudan Black B ◽  
Erysiphe Graminis Hordei ◽  
Sudan Iv ◽  
Mother Cells ◽  
Hyphal Tip

Osmiophilic bodies appear in parts of the colonial growth of Erysiphe graminis DC. f. sp. hordei Em Marchal culture CR3 growing on the susceptible commercial Keystone variety of barley. They are readily observed by the light and electron microscope after osmium tetroxide staining and are abundant in conidiophores, conidia, and mycelium except in haustorial mother cells, in which they are usually absent. The metabolism of haustorial mother cells is distinct and the fine structure of adjoining cells is frequently different. Osmiophilic bodies are absent from the growing hyphal tip, but gradually increase in number and size further back in the terminal cell. Electron micrographs show that they are intracytoplasmic, intravacuolar, and up to 1 μ in diameter. When the colony is washed with acetone or alcohol rather than with aqueous buffer, after glutaraldehyde fixation, before osmium tetroxide fixation, the osmiophilic bodies are removed, indicating that they are lipids. Fat stains, Sudan black B, and Sudan IV stain these bodies. Perhaps the water needs of the germinating conidium are met in part by the oxidation of fats.

THE EMBRYOLOGY OF LYTTA VIRIDANA LE CONTE (COLEOPTERA: MELOIDAE): II. THE STRUCTURE OF THE VITELLINE MEMBRANE

1967 ◽  
Vol 45 (4) ◽  
pp. 497-503 ◽  
Author(s):  
R. G. Gerrity ◽  
J. G. Rempel ◽  
P. R. Sweeny ◽  
N. S. Church
Keyword(s):  
Fine Structure ◽  
Electron Microscope ◽  
Light Microscope ◽  
Three Dimensional ◽  
Apparent Porosity ◽  
Vitelline Membrane ◽  
Sperm Penetration

This paper deals with the structure of the vitelline membrane of Lytta viridana as seen through the light microscope and the electron microscope. Through the light microscope, the vitelline membrane of a freshly laid egg appears to be porous. This condition persists for 15–30 min. During this time the pores become progressively smaller until the membrane becomes solid and continuous. The electron microscope reveals that the vitelline membrane of the freshly laid egg is actually composed of a three-dimensional membranous system which condenses into a homogeneous membrane after 15–30 min. The apparent porosity of the membrane as seen through the light microscope is interpreted in terms of its fine structure, and the belief is expressed that solidification of the membranous system is initiated by sperm penetration.

Fine Structure of the Nucleolus in Normal and Mutant Xenopus Embryos

1967 ◽  
Vol 2 (2) ◽  
pp. 151-162
Author(s):  
ELIZABETH D. HAY ◽  
J. B. GURDON
Keyword(s):  
Fine Structure ◽  
Electron Microscope ◽  
Xenopus Laevis ◽  
Fibrous Material ◽  
Osmium Tetroxide ◽  
Wild Type ◽  
Granular Component ◽  
Basic Dyes ◽  
Fibrillar Component ◽  
Xenopus Laevis Embryos

Mutant and normal Xenopus laevis embryos (0-nu, 1-nu, 2-nu) were examined in the electron microscope after glutaraldehyde and/or osmium-tetroxide fixation. During cleavage both 0-nu and wild-type embryos contain multiple small nucleolar bodies, less than 1 µ in diameter, composed mainly of a fibrous material. By the end of cleavage or beginning of gastrulation, granular caps develop on the fibrous nucleolar bodies. In 1-and 2-nu cells, the multiple nucleolar bodies are replaced during gastrula and neurula stages by definitive nucleoli (2-5 µ in diameter) which contain abundant small (150 Å) granules intermingled with fibrous material. In 0-nu cells, one or two pseudonucleoli (1-3 µ in diameter) appear at about the same time that definitive nucleoli develop in wild-type cells. The multiple small nucleolar bodies disappear as the pseudonucleoli enlarge. Pseudonucleoli differ from definitive nucleoli in having a much smaller amount of the granular component, which is located as a cap on the periphery of the fibrous component and not mingled with it. The granular component of the 0-nu pseudonucleoli, however, is not distinguishable in its fine structure from the same component of normal nucleoli. In many 0-nu tadpoles at stage 41, the granular component of the nucleolus is entirely absent and the fibrillar component is very prominent. Both granular and fibrous components of the 0-nu pseudonucleoli contain RNA as judged by RNase sensitivity and staining affinity for basic dyes.

Cytoplasmic fine-structure

1958 ◽  
Vol 148 (932) ◽  
pp. 290-308 ◽  
Keyword(s):  
Fine Structure ◽  
Electron Microscope ◽  
Large Body ◽  
Cell Types ◽  
General Terms ◽  
Thin Sectioning ◽  
Cytoplasmic Change ◽  
Cellular Specialization ◽  
Different Cell Types ◽  
Made In

In any attempt to reach an integrated conception of the cytoplasm in variation and development, a study of the fine-structure of the cytoplasm and its relation to the nucleus must take its proper place. It is the object of our paper to survey, as adequately as we are able in a limited space, selected data on cytoplasmic fine-structure and we hope that this will provide the Discussion with a background against which to consider a morphological basis for that variation which genetical studies may show to be due to changes in the organization of the cytoplasm. It is possibly too early as yet to hope that examination of the morphology of cells by means of the electron microscope will reveal cytoplasmic differences between organisms which differ from one another in the characteristics studied in genetical experiments; it would be useful to the future study of the problem of Cytoplasmic change, however, to know within what limits speculation must be reasonably confined by the nature of the fine-structure of the cytoplasm. It is now becoming apparent that though cells of organisms widely separated phylogenetically have basic similarities, cellular specialization has led to some diversity in the fine-structure. In the first part of the paper we shall briefly consider the development of electron-microscope methods, e.g. the thin-sectioning procedures, which have made it possible to examine biological material at a resolution which allows comparatively small macromolecular units to be distinguished (10 to 50 Å); at the same time we shall emphasize the danger of overestimating the significance of the observations that have been made. In the second part we shall consider certain selected features of the cell in some detail; in view of the large body of literature on cell fine-structure that is now available (publications numbered over 100 during the last 6 months of 1956) no attempt will be made to review all the findings which have been published during the last few years. Rather we will consider, in general terms, the structure of each component, then compare the variations in structural form noted in different cell types and indicate where there is direct disagreement in the findings of various authorities.

scholarly journals Electron Microscopy of Retinal Photoreceptors

1960 ◽  
Vol 7 (3) ◽  
pp. 493-497 ◽  
Author(s):  
Arnaldo Lasansky ◽  
Eduardo de Robertis
Keyword(s):  
Electron Microscopy ◽  
Fine Structure ◽  
Electron Microscope ◽  
Outer Segment ◽  
Osmium Tetroxide ◽  
The Other ◽  
Rod Outer Segments ◽  
Outer Segments ◽  
Retinal Photoreceptors ◽  
L1 And L2

The fine structure of the cone and rod outer segments of the toad was studied under the electron microscope after fixation in osmium tetroxide and fixation in formaldehyde followed by chromation. In the OsO4-fixed specimens, the rod outer segment appears to be built of a stack of lobulated flattened sacs, each of which is made of two membranes of about 40 A separated by an innerspace of about 30 A. The distance between the rod sacs is about 50 A. The sacs in the cone outer segment are originated by the folding of a continuous membrane. The thickness of the membranes and width of the spaces between the cone sacs is the same as in rod, but the sac innerspace is slightly narrower in the cone (∼ 20 A). After fixation in formaldehyde and chromation, two different dense lines (l1 and l2) separated by spaces of less density appear. One of the lines, l1, has a thickness of 70 A and is less dense than the other, l2, which is 30 A thick. The correlation of the patterns obtained with both fixatives is considered and two possible interpretations are given. The possibility that l2 is related to a soluble phospholipid component is discussed. It is suggested that the outer segments have a paracrystallin organization similar to that found in myelin.

The distribution and fine structure of the integumentary papillae of the cercaria ofHimasthla secunda(Nicoll)

Parasitology ◽  
1970 ◽  
Vol 61 (2) ◽  
pp. 219-227 ◽  
Author(s):  
H. D. Chapman ◽  
R. A. Wilson
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Spatial Distribution ◽  
Fine Structure ◽  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Silver Nitrate ◽  
Light Microscope ◽  
Transmission Electron ◽  
Scanning Electron

The distribution of the integumentary papillae of the cercaria ofHimasthla secundahas been studied by a variety of techniques. Structures stained by silver nitrate and visible under the light microscope correspond in their spatial distribution with papillae observed under the scanning electron microscope. The tegumentary papillae described with the light and scanning electron microscope are correlated with the specialized nerve endings in the tegument as seen in transmission electron microscopy. The ultrastructure of these papillae is examined by conventional transmission electron microscopy and the probability that these structures are sensory is discussed.

The fine structure of the body wall of Polymorphus minutus (Goeze, 1782) (Acanthocephala)

Parasitology ◽  
1965 ◽  
Vol 55 (2) ◽  
pp. 357-364 ◽  
Author(s):  
D. W. T. Crompton ◽  
D. L. Lee
Keyword(s):  
Fine Structure ◽  
Electron Microscope ◽  
Light Microscope ◽  
Body Wall ◽  
Technical Assistance ◽  
The Body ◽  
Parasitic Nematodes ◽  
Surface Layers ◽  
Longitudinal Muscles

The body wall of Polymorphus minutus has been studied with the electron microscope and the structure of the various layers has been described.The layers are the same in number as those seen with the light microscope, and pores have been found which penetrate the cuticle. Thus, the structure of the surface layers is such as would facilitate the absorption of nutrients.It has been found that the cuticle and striped layer extend over the trunk spines, a feature which increases the area of the absorptive surface of the parasite.The structure of the striped layer of the praesoma supports the theory that the praesoma body wall and lemnisci are involved in the absorption of fat.Mitochondria have been detected in the felt and radial layers of the body wall and in the circular and longitudinal muscles.The body wall of this acanthocephalan worm is entirely different from the body wall of trematodes, cestodes and parasitic nematodes.We are grateful to Dr P. Tate for helpful discussions, Dr R. J. Skaer for criticism of the manuscript and to Professor J. D. Boyd for permission to use the electron microscope in the Department of Anatomy. Thanks are also due to Mr A. J. Page for technical assistance.

scholarly journals STUDIES ON CILIA

1963 ◽  
Vol 18 (2) ◽  
pp. 345-365 ◽  
Author(s):  
Peter Satir
Keyword(s):  
Fine Structure ◽  
Electron Microscope ◽  
Cross Section ◽  
Osmium Tetroxide ◽  
Freshwater Mussel ◽  
Structure And Function ◽  
Spring Water ◽  
Fine Structure And Function ◽  
And Function ◽  
Active Preparation

Upon excision into spring water, the lateral cilia of the gill of the freshwater mussel Elliptio complanatus (Solander) stop beating, but 0.04 M potassium ion can activate the gill so that these cilia again beat with metachronal rhythm. One per cent osmium tetroxide quickly pipetted onto a fully activated gill fixes the lateral cilia in a pattern that preserves the form and arrangement of the metachronal wave, and permits the cilia to be studied with the electron microscope in all stages of their beat cycle. Changes are seen in the fixed active preparation that are not present in the inactive control, i.e., in the packing of the cilia, the position of the axis of the ciliary cross-section, and the diameter of the ring of peripheral filaments. Analysis of these parameters may lead to new correlations between ciliary fine structure and function.

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