AN ELECTRON MICROSCOPIC STUDY OF THE PARATHYROID GLANDS IN MAN: EVIDENCE OF SECRETORY MATERIAL

1969 ◽  
Vol 61 (2) ◽  
pp. 334-342 ◽  
Author(s):  
Richard J. Weymouth ◽  
Hugo R. Seibel
Keyword(s):  
Endothelial Cells ◽  
Microscopic Study ◽  
Electron Microscopic Study ◽  
Functional Significance ◽  
Metabolic Process ◽  
Parathyroid Glands ◽  
Secretory Material ◽  
Electron Microscopic ◽  
Dense Bodies ◽  
Transitional Cells

ABSTRACT The ultrastructure of one hyperplastic and three adenomatous parathyroid glands have been described. Electron dense bodies measuring 0.08–0.5 microns in diameter and similar to those reported by Roth & Munger (1962) and Weymouth & Sheridan (1966) were described. These bodies were increased in number in the pathological glands, observed primarily at the vascular pole of the cell and frequently within the adjoining endothelial cells. Similar structures were found frequently within the mitochondria. In all probability, these electron dense bodies represent secretory material; the mitochondria play an intimate role in this metabolic process of secretion. Large, whorl-shaped structures, composed of concentric membranes, were also described. These structures may be of functional significance in hypersecreting glands, since they were observed in the pathological parathyroid glands only. »Transitional« cells were readily apparent.

The Brindley's glands of Rhodnius prolixus. I. Structure of the mature gland

1979 ◽  
Vol 57 (5) ◽  
pp. 1109-1119 ◽  
Author(s):  
F. M. Barrett ◽  
B. F. Millen ◽  
J. Lai-Fook
Keyword(s):  
Microscopic Study ◽  
Electron Microscopic Study ◽  
Functional Significance ◽  
Type A ◽  
Rhodnius Prolixus ◽  
Type B ◽  
Electron Microscopic ◽  
Dermal Glands ◽  
Similarities And Differences ◽  
Secretory Apparatus

A detailed light and electron microscopic study of the Brindley's glands of adult Rhodnius prolixus has confirmed the presence of type B glandular units similar to those described for the dermal glands of Rhodnius and has identified the second type A glandular unit, also composed of secretory apparatus, saccule, and duct, but outnumbered approximately 18:1 by the type B units. Similarities and differences between type A and type B glandular units are described and the possible functional significance of the two types of unit is discussed.

scholarly journals Interaction of Listeria monocytogenes with Human Brain Microvascular Endothelial Cells: an Electron Microscopic Study

2000 ◽  
Vol 68 (6) ◽  
pp. 3275-3279 ◽  
Author(s):  
Lars Greiffenberg ◽  
Werner Goebel ◽  
Kwang Sik Kim ◽  
Justin Daniels ◽  
Michael Kuhn
Keyword(s):  
Endothelial Cells ◽  
Listeria Monocytogenes ◽  
Human Brain ◽  
Microscopic Study ◽  
Electron Microscopic Study ◽  
Microvascular Endothelial Cells ◽  
Brain Microvascular Endothelial Cells ◽  
Electron Microscopic ◽  
Independent Manner ◽  
Microvascular Endothelial

ABSTRACT Internalization of Listeria monocytogenes into human brain microvascular endothelial cells (HBMEC) has recently been demonstrated to be dependent upon the inlB gene. In the present scanning electron microscopic study we show that L. monocytogenes efficiently interacts with the surface of HBMEC in an inlB-independent manner which is also different from invasion. The inlB-dependent invasion of HBMEC by L. monocytogenes is accompanied by intracellular multiplication, movement, and production of bacterium-containing protrusions. These protrusions extend from the cell surface without perturbation of any adjacent cellular membrane.

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