The fine structure of epithelial cells in normal and pathological buccal mucosa. II. Colloid body formation

The ampullate silk gland of the spider, Araneus sericatus, produces the silk fiber for the scaffolding of the web. The fine structure of the various parts of the gland is described. The distal portion of the duct consist of a tube of epithelial cells which appear to secrete a substance which forms the tunica intima of the duct wall. At the proximal end of the duct there is a region of secretory cells. The epithelium of the sac portion contains five morphologically distinct types of granules. The bulk of the synthesis of silk occurs in the tail of the gland, and in this region only a single type of secretory droplet is seen in the epithelium. Protein synthesis can be stimulated by the injection of 1 mg/kg acetylcholine into the body fluids. 10 min after injection, much of the protein stored in the cytoplasm of the epithelial cells has been secreted into the lumen. 20 min after stimulation, the ergastoplasmic sacs form large whorls in the cytoplasm. Protein, similar in electron-opacity to protein found in the lumen, begins to form in that portion of the cytoplasm which is enclosed by the whorls. The limiting membrane of these droplets is formed by ergastoplasmic membranes which lose their ribosomes. No Golgi material has been found in these cells. Protein appears to be manufactured in the cytoplasm of the tail cells in a form which is ready for secretion.

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Fine structure and development of schizonts, merozoites and macrogamonts of Eimeria acervulina in the goblet cells of the duodenal epithelium of experimentally infected birds

Parasitology ◽

10.1017/s0031182000049684 ◽

1975 ◽

Vol 70 (2) ◽

pp. 223-229 ◽

Cited By ~ 7

Author(s):

E. Michael

Keyword(s):

Fine Structure ◽

Epithelial Cells ◽

Golgi Apparatus ◽

Host Cell ◽

Goblet Cells ◽

Cellular Level ◽

Site Specificity ◽

Eimeria Acervulina ◽

Duodenal Epithelium

The fine structure of trophozoites, schizonts, merozoites and macrogamonts of Eimeria acervulina found in goblet cells of the duodenal epithelium of chicks is described and compared with the corresponding stages formed in other epithelial cells. Complete schizogony, with the formation of mature merozoites, occurred freely in goblet cells. Developing macrogamonts (but no microgamonts) were rarely found in goblet cells. The stages observed were confined to the cytoplasm of the host cell above the Golgi apparatus and were usually seen between the mucous granules. The stages seen appeared normal, and contained similar structures to corresponding stages developing in other cells. The finding of developing stages of E. acervulina in goblet cells provides further evidence that site specificity of Eimeria at the cellular level is not as strict as previously thought.

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Assessment of Karyorrhexis Incidence in Exfoliated Buccal Mucosa Epithelial Cells among Fuel Station Employees in Sleman, Special Region of Yogyakarta, Indonesia

International Journal of Experimental Dental Science ◽

10.5005/jp-journals-10029-1216 ◽

2020 ◽

Vol 9 (2) ◽

pp. 62-69

Author(s):

Regina TC Tandelilin ◽

Tang Sze Mun ◽

Tetiana Haniastuti

Keyword(s):

Epithelial Cells ◽

Buccal Mucosa ◽

Special Region

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Peroxiredoxin I expression in epithelial cells of buccal mucosa from patients exposed to panoramic X-rays: influence of the age

Clinical Oral Investigations ◽

10.1007/s00784-017-2254-4 ◽

2017 ◽

Vol 22 (3) ◽

pp. 1587-1592 ◽

Cited By ~ 1

Author(s):

Milena B. Silva ◽

Ana P. D. Demasi ◽

Elizabeth F. Martinez ◽

Maristane L. Goudinho ◽

Joarlene M. Soares ◽

...

Keyword(s):

Epithelial Cells ◽

Buccal Mucosa ◽

X Rays ◽

Peroxiredoxin I

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Changes in the fine structure of the apical plasma membrane of endometrial epithelial cells during implantation in the rat

Journal of Cell Science ◽

10.1242/jcs.55.1.1 ◽

1982 ◽

Vol 55 (1) ◽

pp. 1-12

Author(s):

C.R. Murphy ◽

J.G. Swift ◽

T.M. Mukherjee ◽

A.W. Rogers

Keyword(s):

Plasma Membrane ◽

Fine Structure ◽

Epithelial Cells ◽

Normal Pregnancy ◽

Ovariectomized Rats ◽

Apical Plasma Membrane ◽

Embryonic Cells ◽

Blastocyst Implantation ◽

First Contact ◽

Endometrial Epithelial Cells

In previous work we have shown that ovarian hormones, when injected into ovariectomized rats, alter the fine structure of the plasma membrane of endometrial epithelial cells. In this paper freeze-fractures have been used to study the apical plasma membrane of endometrial epithelial cells of rats during the period of blastocyst implantation of normal pregnancy. On day 1 of pregnancy there were 2354 +/− 114 intramembranous particles (IMPs) per micrometer2 of membrane. The particles were spherical and randomly distributed. On day 5 of pregnancy IMP density rose to 2899 +/− 289 per micrometer2 and some rod-shaped particles were also visible. By day 6 of pregnancy IMP density had risen to 4014 +/− 206 per micrometer2 and there were more rod-shaped IMPs than before. In addition, on day 6 IMPs were also present as rows of particles and some gap-junction-like arrays of particles were also seen. Our findings indicate that there are fine-structural alterations in the apical plasma membrane of endometrial epithelial cells, the site of first contact between maternal and embryonic cells, during the period of early pregnancy. The findings are discussed in the light of suggested mechanisms of blastocyst attachment to the uterine epithelium at implantation.

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The Fine Structure of the Respiratory Tree in Cucumaria

Journal of Cell Science ◽

10.1242/jcs.s3-105.69.7 ◽

1964 ◽

Vol s3-105 (69) ◽

pp. 7-11

Author(s):

WILLIAM L. DOYLE ◽

G. FRANCES McNIELL

Keyword(s):

Endoplasmic Reticulum ◽

Smooth Muscle ◽

Fine Structure ◽

Epithelial Cells ◽

Secretory Activity ◽

Muscle Fibres ◽

Coelomic Epithelium ◽

Free Surfaces ◽

Respiratory Tree ◽

Synchronous Contraction

The delicate tubules of the respiratory tree consist of 4 layers: a lining epithelium, a thick mucoid layer containing collagenous filaments, a smooth muscle net, and a coelomic epithelium. The free surfaces of both epithelia have well developed plasmodesms. Amoebocytes are present in all layers and the spherules of one type are considered to be precursors of the mucoid substance; another amoebocyte may be a fibroblast. Perpendicularly oriented smooth muscle fibres, as well as those parallel to each other, are linked by desmosomes ensuring synchronous contraction. Secretory activity is evident in distended cisternae of the endoplasmic reticulum of certain epithelial cells and in the vacuoles of the lining epithelium.

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