An electron microscope study of the tegument of the metacercaria and adult of Leucochloridiomorpha constantiae (Trematoda: Brachylaemidae)

The tegumentary ultrastructure of Leucochloridiomorpha constantiae metacercariae and adults has been described. A filamentous glycocalyx invests the tegument of metacercariae and large numbers of biconcave, disk-shaped secretion vesicles are found in its outer zone, cytoplasmic bridges and cytons. Mitochondria within the outer tegumentary zone of metacercariae are restricted to its basal half. The transformation of metacercariae to adults involves the loss of the glycocalyx, a decrease in the number of disk-shaped secretion vesicles, a more uniform distribution of mitochondria through the outer tegumentary zone, an apparent degeneration of cytons, a thinning of the fibrous basal lamina and a decrease in the number of visible cytoplasmic bridges traversing it. The significance of these events for a metacercaria which does not encyst within the molluscan host is discussed. In addition, crystalline, spine-like inclusions in the outer tegumentary zone of adult L. constantiae are described and their possible function discussed.

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Basal lamina fenestrations in the human colon: Transmission and scanning electron microscope study

The Anatomical Record ◽

10.1002/ar.1092200109 ◽

1988 ◽

Vol 220 (1) ◽

pp. 68-75 ◽

Cited By ~ 12

Author(s):

K. A. Warfel ◽

Meredith T. Hull

Keyword(s):

Electron Microscope ◽

Scanning Electron Microscope ◽

Basal Lamina ◽

Microscope Study ◽

Electron Microscope Study ◽

Human Colon ◽

Scanning Electron Microscope Study ◽

Scanning Electron

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The Egg Shell of the House Cricket (Acheta Domesticus): An Electron-Microscope Study

Journal of Cell Science ◽

10.1242/jcs.5.1.227 ◽

1969 ◽

Vol 5 (1) ◽

pp. 227-249

Author(s):

P. J. S. FURNEAUX ◽

C. R. JAMES ◽

S. A. POTTER

Keyword(s):

Fine Structure ◽

Electron Microscope ◽

Microscope Study ◽

Electron Microscope Study ◽

Outer Zone ◽

Acheta Domesticus ◽

Vitelline Membrane ◽

House Cricket ◽

Stable Part ◽

Egg Shell

Consecutive changes in two discrete layers of the egg shell of the house cricket, Acheta domesticus, have been claimed to control the uptake of water by the eggs. The development of the shell has been re-investigated with the electron microscope by examination of eggs at different stages of embryogenesis and of ovarioles containing oocytes at various stages of maturity. It is confirmed that fragmentation of the maternal epicuticle and deposition and resorption of the serosal cuticle are the only apparent changes in the shell during development. The existence of a serosal epicuticle is confirmed and a distinction is made between the serosal epicuticle and the vitelline membrane. Previously unreported features of the shell are (i) an outer zone of the maternal endocuticle which seems to be the most stable part of the maternal cuticle, (ii) a microlaminar organization within the scales of the maternal epicuticle, (iii) a vitelline membrane containing specialized regions, which remains distinct from the serosal epicuticle throughout development, and (iv) the osmiophilic character of the serosal epicuticle, its complex fine structure and its origin. Observations on eggs which had just begun to absorb water allow us to suggest that fragmentation involves a shrinkage of the material of which the scales are composed.

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ELECTRON MICROSCOPE STUDY OF THE VITELLINE BODY OF SOME SPIDER OOCYTES

The Journal of Cell Biology ◽

10.1083/jcb.3.2.301 ◽

1957 ◽

Vol 3 (2) ◽

pp. 301-310 ◽

Cited By ~ 46

Author(s):

J. Roberto Sotelo ◽

Omar Trujillo-Cenóz

Keyword(s):

Endoplasmic Reticulum ◽

Optical Properties ◽

Electron Microscope ◽

Microscope Study ◽

Electron Microscope Study ◽

Central Core ◽

Composite Body ◽

Double Membrane ◽

Peripheral Layer ◽

Large Numbers

The structure of the vitelline nuclei of Lycosidae and Thomisidae was described as follows: Vitelline nuclei are constituted of two parts: (a) a peripheral layer (vitelline body cortex), and (b) a central core. The vitelline body cortex is demonstrated to be formed by many cisternae of the endoplasmic reticulum among which mitochondria and Golgi elements are intermingled. The central core is made up mainly of a special type of body described under the name of "capsulated body." Capsulated bodies comprise a capsular layer, limited by a membrane, and two central masses called "geminated masses," each one limited by a double membrane. Irregular masses of closely packed vesicles are found in some cases among the capsulated bodies and free vesicles are present in large numbers. The optical properties of the vitelline body cortex compared with the electron microscope findings lead us to the concept that this layer is a "composite body" according to Weiner's theory.

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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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