Electron microscope study on the occurrence of electron-dense deposits at the cell membrane of chicken erythrocytes

The fine structure of a species of small free-living amoeba, Hartmanella astronyxis, has been investigated. The mitochondria resemble those of other species of amoeba. Structureless bodies of about the same size as mitochondria are sometimes found in association with them. Double membranes are common in the cytoplasm, and may show granules along their outer borders. The nuclear membrane is a double-layered structure, with a honeycomb structure evident in tangential sections. The cell membrane is also double-layered, or occasionally multi-layered.

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The Fine Structure of Some Retinal Photoreceptors

The Journal of Cell Biology ◽

10.1083/jcb.7.1.87 ◽

1960 ◽

Vol 7 (1) ◽

pp. 87-92 ◽

Cited By ~ 124

Author(s):

M. F. Moody ◽

J. D. Robertson

Keyword(s):

Fine Structure ◽

Electron Microscope ◽

Cell Membrane ◽

Microscope Study ◽

Electron Microscope Study ◽

Double Membrane ◽

Double Structure ◽

Rods And Cones ◽

Retinal Photoreceptors ◽

Bounding Surfaces

An electron microscope study has been made of octopus and amphibian photoreceptors, after fixing with KMnO4 and embedding in araldite. What has previously been seen as a single dense stratum bounding the tubular compartments (octopus) or the double membrane discs (rods and cones), now shows a double structure. We interpret this as showing that these tubules and discs have similar bounding surfaces, which are probably directly related to the cell membrane. This is confirmed by the finding that the tubules and discs are (at least occasionally) continuous with the cell membrane.

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TRICOMPLEX FIXATION OF PHOSPHOLIPIDS

The Journal of Cell Biology ◽

10.1083/jcb.24.1.23 ◽

1965 ◽

Vol 24 (1) ◽

pp. 23-30 ◽

Cited By ~ 50

Author(s):

P. F. Elbers ◽

P. H. J. T. Ververgaert ◽

R. Demel

Keyword(s):

Electron Microscope ◽

Cell Membrane ◽

Mode Of Action ◽

Microscope Study ◽

Electron Microscope Study ◽

Osmium Tetroxide ◽

Fixation Method ◽

Brain Phospholipids ◽

Tricomplex Flocculation ◽

Colloid Systems

A basis for the interpretation of the structure of the cell membrane is often looked for in electron microscope investigations on the structure of lipid models. A difficulty in these investigations is our lack of knowledge of the effect of the preparative treatment on the structure studied. This applies especially to the strongly oxidizing fixatives: osmium tetroxide and potassium permanganate. These agents have, moreover, the drawback that they cannot be used to fix fully saturated lipids. On the basis of existing theories concerning complex colloid systems, a fixation method was developed that allows the electron microscope study of the structure of phospholipid models, irrespective of whether they consist of saturated or unsaturated compounds. With this fixation, namely tricomplex flocculation by means of suitable ions, the structure of the lipid molecules is not altered. Moreover, the site and mode of action of this fixation are well known. The first application of this method to the study of isolated beef brain phospholipids is described.

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Ultrastructure of Plant Leaf Tissue Infected with Mite-Borne Viral-Like Pathogens

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100067881 ◽

1970 ◽

Vol 28 ◽

pp. 178-179 ◽

Cited By ~ 2

Author(s):

O. E. Bradfute ◽

R. E. Whitmoyer ◽

L. R. Nault

Keyword(s):

Triticum Aestivum ◽

Zea Mays ◽

Electron Microscope ◽

Hordeum Vulgare ◽

Microscope Study ◽

Electron Microscope Study ◽

Leaf Tissue ◽

Leaf Ultrastructure ◽

Double Membrane ◽

Aceria Tulipae

A pathogen transmitted by the eriophyid mite, Aceria tulipae, infects a number of Gramineae producing symptoms similar to wheat spot mosaic virus (1). An electron microscope study of leaf ultrastructure from systemically infected Zea mays, Hordeum vulgare, and Triticum aestivum showed the presence of ovoid, double membrane bodies (0.1 - 0.2 microns) in the cytoplasm of parenchyma, phloem and epidermis cells (Fig. 1 ).

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Electron microscope study of the microgranules in human vaginal epithelium

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100083710 ◽

1978 ◽

Vol 36 (2) ◽

pp. 568-569

Author(s):

A. Campos ◽

J. Vilches ◽

J. Gomez

Keyword(s):

Electron Microscope ◽

Microscope Study ◽

Intercellular Space ◽

Electron Microscope Study ◽

Vaginal Epithelium ◽

Vaginal Mucosa ◽

Secretory Phase ◽

Cervical Epithelium ◽

Keratinized Epithelium ◽

Fertile Women

Microgranules have been described with different names in keratinized and in nonkeratinized epithelium. In keratinized epithelium it seems clear that the microgranules are lamellated bodies bounded by a membrane which empty their contents into the intercellular space. Their existence in nonkeratinized epithelium is more debatable. Until now the so-called microgranules have been described in nonkeratinized bucal, lingual and cervical epithelium. In the present work we describe the morphology and nature of such structures in human vaginal epithelium.Biopsies from the midlevel of the vaginal mucosa were taken from voluntary fertile women. The specimens were divided into three groups with four vaginal specimens. The first group was obtained in the folicular phase; those of the second in the postovulatory phase and, finally, the last group corresponded to the secretory phase.

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