scholarly journals THE FINE STRUCTURE OF MEISSNER's TOUCH CORPUSCLES OF HUMAN FINGERS

1960 ◽  
Vol 8 (2) ◽  
pp. 467-482 ◽  
Author(s):  
Nikolajs Cauna ◽  
Leonard L. Ross
Keyword(s):  
Nerve Fibers ◽  
Nerve Endings ◽  
Osmic Acid ◽  
Electron Microscopic ◽  
Material Loss ◽  
Intercellular Substance ◽  
Thin Sections ◽  
Perinuclear Cytoplasm ◽  
Meissner’S Corpuscle ◽  
Dense Vesicles

Thin slices of the finger pads of six individuals were fixed in buffered 1 per cent osmic acid, embedded in deaerated, nitrogenated methacrylate, and cut into thin sections for electron microscopic study. Before embedding, the slices were trimmed so as to include several digital tactile corpuscles. Some thin sections were stained in 10 per cent aqueous phosphotungstic acid solution. The principal part of Meissner's corpuscle is made up of flattened laminar cells stretching across the corpuscle in irregular layers. The perinuclear cytoplasm of these cells contains numerous small mitochondria, a sparse granular endoplasmic reticulum, and a large number of small vesicles. Nerve fibers enter the side or base of the corpuscle, lose their myelin sheaths, and follow a meandering course between the laminar cell plates. The nerve endings enter into a close appositional relationship with the flattened portions of the laminar cells. In some areas the apposed axolemma and cell membranes are slightly thickened with small vesicles located along the cell membrane or on both surfaces. These regions are interpreted as synapses. The most prominent feature of the nerve endings is an extraordinary accumulation of small mitochondria which vary in size and internal density. The nerve endings also contain vacuoles, groups of dense concentric membranes, and small dense vesicles of irregular distribution. The laminar cells are separated from one another by a dense intercellular substance of uniform thickness which also envelops the entire corpuscle. This material contains randomly oriented collagen fibers and fine fibrils bound together by a dense material at nodal points recurring at regular intervals of approximately 120 mµ. These findings are discussed in relation to the problems of the function of Meissner's corpuscle, neural material loss and replacement, and the presence of synapses.

scholarly journals Electron Microscopic Observations of the Carotid Body of the Cat

1959 ◽  
Vol 6 (2) ◽  
pp. 253-262 ◽  
Author(s):  
Leonard L. Ross
Keyword(s):  
Golgi Complex ◽  
Carotid Body ◽  
Nerve Fibers ◽  
Osmic Acid ◽  
Electron Microscopic ◽  
Thin Sections ◽  
Sustentacular Cells ◽  
Carotid Bodies ◽  
Unmyelinated Nerve ◽  
Chemoreceptor Cells

Carotid bodies were removed from cats, fixed in buffered 1 per cent osmic acid, embedded in deaerated, nitrogenated methacrylate, and cut into thin sections for electron microscopic study. The carotid body is seen to be composed of islands of chemoreceptor and sustentacular cells surrounded by wide irregular sinusoids. These cells are separated from the sinusoids by relatively broad interstitial spaces which are filled with collagen, fibroblasts, and many unmyelinated nerve fibers with their Schwann cell sheaths. The chemoreceptor cells are surrounded by the flattened, multiprocessed sustentacular cells which serve to convey the axons from an interstitial to a pericellular location. These sustentacular cells are assumed to be lemmoblastic in origin. Relatively few axons are seen to abut on the chemoreceptor cells. The cytoplasm of the chemoreceptor cell is characterized by numerous small mitochondria, units of granular endoplasmic reticulum, a small Golgi complex, and a variety of vesicles. There are many small vesicles diffusely scattered throughout the cytoplasm. In addition, there is a small number of dark-cored vesicles of the type which has been previously described in the adrenal medulla. These are usually associated with the Golgi complex. These findings are discussed in relation to the concepts of the origin of the chemoreceptor cell and the nature of the synapse.

Sensory Nerve Endings in the Mucosa of the Epiglottis—Morphologic Investigations with Silver Impregnation, Immunohistochemistry, and Electron Microscopy

1987 ◽  
Vol 96 (1) ◽  
pp. 55-62 ◽  
Author(s):  
Takemoto Shin ◽  
Shun Watanabe ◽  
Shigeru Wada ◽  
Tadatsugu Maeyama
Keyword(s):  
Electron Microscopy ◽  
Substance P ◽  
Sensory Nerve ◽  
Nerve Fibers ◽  
Silver Impregnation ◽  
Taste Bud ◽  
Nerve Endings ◽  
Electron Microscopic ◽  
Sensory Nerve Endings ◽  
Microscopic Studies

This study was conducted in order to investigate the structure of sensory nerve endings of the human epiglottis and substance P immunoreactive nerve fibers of the canine epiglottis in relationship to physiologic functions of the larynx. The human epiglottis was observed by light microscopy (silver impregnation) and electron microscopy, and the canine epiglottis was studied by peroxidase-anti-peroxidase (PAP) immunohistochemistry. The results are summarized as follows: (1) In the membranes of the epiglottis, we observed free endings of simple or complex tree shape, corpuscle endings with glomerular patterns, and taste-bud-like structures, and (2) electron microscopic studies revealed varicosity of the terminal axon with processes that contained small, clear and large, dense cored vesicles. Substance P was observed in these structures, and it was suggested that substance P was related to perception in the larynx.

Ultrastructure of Oviduct Epithelium of the Porcine in Estrus

1971 ◽  
Vol 29 ◽  
pp. 512-513
Author(s):  
R. K. Nayak ◽  
D. R. Zimmerman
Keyword(s):  
Intercellular Junctions ◽  
Uranyl Acetate ◽  
Secretory Process ◽  
Osmic Acid ◽  
Electron Microscopic ◽  
Thin Sections ◽  
Tissue Sections ◽  
Oviduct Epithelium ◽  
Microscopic Studies ◽  
Cyclic Changes

Cyclic changes of porcine oviduct epithelium studied by light microscopy were first reported by Snyder in 1923. UltrastructuraI features of the porcine oviduct epithelium have not yet been described. Electron microscopic studies of oviduct epithelium have been reported for only a few species. These reports have been recently reviewed by Nilsson and Relnius. This report describes the fine structure of, the oviduct epithelium and attempts to elucidate the mechanism of ciliogenesis and the secretory process in the porcine during estrus.Tissue sections from the fimbria and ampulla were fixed in cold 3% cacodylate buffered glutaraldehyde (pH 7.4), post-fixed in 1% osmic acid and embedded in Epon. Ultra-thin sections were stained with uranyl acetate and lead citrate and examined in a RCA 3-G electron microscope operated at 100 kv.The epithelium of the tubal mucosa consists of secretory and ciliated cells. The cells are columnar and rest on a common basement membrane, which is about 50 mμ thick. The distal or free borders of the surface epithelial cells possess few irregular microvilli. The membranes of adjacent cells show tight intercellular junctions and macula adhaerentes (Figs. 1, 2).

scholarly journals Complete penetration of antibodies into vibratome sections after glutaraldehyde fixation and ethanol treatment: light and electron microscopy for neuropeptides.

1992 ◽  
Vol 40 (11) ◽  
pp. 1741-1749 ◽  
Author(s):  
I J Llewellyn-Smith ◽  
J B Minson
Keyword(s):  
Spinal Cord ◽  
Light And Electron Microscopy ◽  
Nerve Fibers ◽  
Ethanol Treatment ◽  
Electron Microscopic ◽  
Cytoplasmic Matrix ◽  
Thin Sections ◽  
High Concentrations ◽  
Ethanol Washing ◽  
Ethanol Ethanol

To develop a method for quantitative electron microscopic immunocytochemistry on neural tissue of CNS, we tested the extent to which ethanol treatment would improve the penetration of immunoreagents through vibratome sections fixed in high concentrations of glutaraldehyde without compromising ultrastructure. Transverse or sagittal vibratome sections (60-80 microns) of spinal cord perfused with 1% formaldehyde plus 1% or 2.5% glutaraldehyde were washed in 50% ethanol for 0-70 min and stained to reveal immunoreactivity for neuropeptide Y (NPY). Semi-thin (1 micron) or ultra-thin sections were used to assess the depth to which NPY nerve fibers in the dorsal horn were stained. Without ethanol washing, immunoreactive nerve fibers were visualized only in the surface 5-10 microns of transverse or sagittal vibratome sections. In transverse vibratome sections, NPY nerve fibers, which ran perpendicular to the cut surfaces of the sections, were entirely stained after a 30-min wash in 50% ethanol. The numbers of NPY-immunoreactive varicosities and synapses were comparable at the surfaces and in the centers of the vibratome sections. In sagittal sections, where NPY nerve fibers ran parallel to the cut surfaces, fibers in the centers of vibratome sections could not be labeled even after 70 min in 50% ethanol. Substance P- and enkephalin (Enk)-immunoreactive nerve fibers could also be completely stained in transverse sections of spinal cord or medulla oblongata after 30-min exposure to ethanol. Ethanol washing had no significant deleterious effects on ultrastructure, although the amount of cytoplasmic matrix in neurons decreased with increasing exposure. These results indicate that washing with 50% ethanol for at least 30 min allows immunoreagents to penetrate completely through nerve fibers fixed with high concentrations of glutaraldehyde, as long as the fibers have cut ends at both surfaces of a vibratome section. This technique makes possible quantitative electron microscopic immunocytochemical studies and is proving a useful tool for defining synaptic connections in the CNS.

scholarly journals Catecholamine innervation of enkephalinergic neurons in guinea pig hypothalamus: demonstration by an in vitro autoradiographic technique combined with a post-embedding immunogold method.

1988 ◽  
Vol 36 (5) ◽  
pp. 533-542 ◽  
Author(s):  
V Mitchell ◽  
J C Beauvillain ◽  
P Poulain ◽  
M Mazzuca
Keyword(s):  
Guinea Pig ◽  
Ultrastructural Level ◽  
Microscopic Level ◽  
Electron Microscopic Level ◽  
Morphological Evidence ◽  
Osmic Acid ◽  
Electron Microscopic ◽  
Double Labeling ◽  
Thin Sections

To study the relationship between the catecholamine (CA) nerve endings and the enkephalinergic cell bodies in the magnocellular dorsal nucleus (MDN) of guinea pig hypothalamus, double-labeling experiments were performed on the same tissue section at the electron microscopic level. An in vitro autoradiographic (ARG) method for [3H]-norepinephrine (NE) or [3H]-dopamine (DA) was combined with a post-embedding immunogold cytochemical technique for Met-enkephalin (Met-enk) in colchicine-treated animals. Hypothalamic slices (450 micrograms) were perfused with [3H]-NE or [3H]-DA at the fluid-gas interface, then fixed by immersion with glutaraldehyde and osmic acid. Semi-thin sections processed from the thickness of the slices showed adequate penetration of the tracers to all parts of the tissue. Frontal sections permitted visualization of some CA-uptake structures distributed around the cells. At the ultrastructural level, preservation appeared good on about 60% of the thickness of slices, and [3H]-CA structures were easily distinguished. Ultra-thin sections were successively incubated with Met-enk and colloidal gold-labeled antisera, followed by ARG processing. At the electron microscopic level, the good integrity of the tissue made possible visualization of [3H]-CA nerve terminals making synaptic contacts with enkephalinergic perikarya. These results provide morphological evidence for direct catecholaminergic control of enkephalinergic neurons of the MDN.

Hemoglobin crystals of the red blood cells in the human renal cortex: electron microscopic observations of the renal lithiasis

1978 ◽  
Vol 36 (2) ◽  
pp. 480-481
Author(s):  
Kosuke Ueda ◽  
Hiroto Washida ◽  
Nakazo Watari
Keyword(s):  
Red Blood Cells ◽  
Blood Cells ◽  
Renal Cortex ◽  
Uranyl Acetate ◽  
Osmic Acid ◽  
Renal Lithiasis ◽  
Electron Microscopic ◽  
Hemoglobin C ◽  
First Case ◽  
Ultrathin Sections

IntroductionHemoglobin crystals in the red blood cells were electronmicroscopically reported by Fawcett in the cat myocardium. In the human, Lessin revealed crystal-containing cells in the periphral blood of hemoglobin C disease patients. We found the hemoglobin crystals and its agglutination in the erythrocytes in the renal cortex of the human renal lithiasis, and these patients had no hematological abnormalities or other diseases out of the renal lithiasis. Hemoglobin crystals in the human erythrocytes were confirmed to be the first case in the kidney.Material and MethodsTen cases of the human renal biopsies were performed on the operations of the seven pyelolithotomies and three ureterolithotomies. The each specimens were primarily fixed in cacodylate buffered 3. 0% glutaraldehyde and post fixed in osmic acid, dehydrated in graded concentrations of ethanol, and then embedded in Epon 812. Ultrathin sections, cut on LKB microtome, were doubly stained with uranyl acetate and lead citrate.

The Immuno-Electron Microscopic Localization of the Mo-Fe Protein Component of Nitrogenase in Cells of Azotobacter Vinelandii

1973 ◽  
Vol 31 ◽  
pp. 574-575
Author(s):  
J. T. Stasny ◽  
R. C. Burns ◽  
R. W. F. Hardy
Keyword(s):  
Cellular Localization ◽  
Direct Evidence ◽  
Azotobacter Vinelandii ◽  
Intracellular Localization ◽  
Protein Component ◽  
Electron Microscopic ◽  
Thin Sections ◽  
Fe Protein ◽  
Intracytoplasmic Membranes

Structure-functlon studies of biological N2-fixation have correlated the presence of the enzyme nitrogenase with increased numbers of intracytoplasmic membranes in Azotobacter. However no direct evidence has been provided for the internal cellular localization of any nitrogenase. Recent advances concerned with the crystallizatiorTand the electron microscopic characterization of the Mo-Fe protein component of Azotobacter nitrogenase, prompted the use of this purified protein to obtain antibodies (Ab) to be conjugated to electron dense markers for the intracellular localization of the protein by electron microscopy. The present study describes the use of ferritin conjugated to goat antitMo-Fe protein immunoglobulin (IgG) and the observations following its topical application to thin sections of N2-grown Azotobacter.

The High Resolution Appearance of Biological Substrates

1969 ◽  
Vol 27 ◽  
pp. 416-417
Author(s):  
Glen B. Haydon
Keyword(s):  
High Resolution ◽  
Phase Image ◽  
Biological Structure ◽  
Electron Microscopic ◽  
Thin Sections ◽  
Resolution Electron ◽  
Discrete Structures ◽  
Large Phase ◽  
Biological Substrates ◽  
High Resolution Electron Micrographs

High resolution electron microscopic study of negatively stained macromolecules and thin sections of tissue embedded in a variety of media are difficult to interpret because of the superimposed phase image granularity. Although all of the information concerning the biological structure of interest may be present in a defocused electron micrograph, the high contrast of large phase image granules produced by the substrate makes it impossible to distinguish the phase ‘points’ from discrete structures of the same dimensions. Theory predicts the findings; however, it does not allow an appreciation of the actual appearance of the image under various conditions. Therefore, though perhaps trivial, training of the cheapest computer produced by mass labor has been undertaken in order to learn to appreciate the factors which affect the appearance of the background in high resolution electron micrographs.

Determination of the phase structure of polymerblends by electron microscopy

1978 ◽  
Vol 36 (1) ◽  
pp. 492-493
Author(s):  
Dr. G. Kaemof
Keyword(s):  
Screw Extruder ◽  
Electron Microscopic ◽  
Thin Sections ◽  
Single Screw Extruder ◽  
Transmission Electron ◽  
The Matrix ◽  
Twin Screw ◽  
Special Case ◽  
Microscopic Investigations

A mixture of polycarbonate (PC) and styrene-acrylonitrile-copolymer (SAN) represents a very good example for the efficiency of electron microscopic investigations concerning the determination of optimum production procedures for high grade product properties.The following parameters have been varied:components of charge (PC : SAN 50 : 50, 60 : 40, 70 : 30), kind of compounding machine (single screw extruder, twin screw extruder, discontinuous kneader), mass-temperature (lowest and highest possible temperature).The transmission electron microscopic investigations (TEM) were carried out on ultra thin sections, the PC-phase of which was selectively etched by triethylamine.The phase transition (matrix to disperse phase) does not occur - as might be expected - at a PC to SAN ratio of 50 : 50, but at a ratio of 65 : 35. Our results show that the matrix is preferably formed by the components with the lower melting viscosity (in this special case SAN), even at concentrations of less than 50 %.

An Electron Microscopic Study of the Acute Effects of Hypothalamic Releasing Factors on the Anterior Pituitary Gland

1968 ◽  
Vol 26 ◽  
pp. 232-233
Author(s):  
P.W. Coates ◽  
E.A. Ashby ◽  
L. Krulich ◽  
A. Dhariwal ◽  
S. McCann
Keyword(s):  
Anterior Pituitary ◽  
Microscopic Investigation ◽  
Uranyl Acetate ◽  
Electron Microscopic Investigation ◽  
Electron Microscopic ◽  
Tissue Samples ◽  
Thin Sections ◽  
Dense Membrane ◽  
Membrane Bound ◽  
Releasing Factors

The morphologic effects on somatotrophs of crude sheep hypothalamic extract prepared from stalk-median eminence were studied by electron microscopy in conjunction with concurrently run bioassays performed on the same tissue samples taken from young adult male Sherman rats.Groups were divided into uninjected controls and injected experimentals sacrificed at 5', 15', and 30' after injection. Half of each anterior pituitary was prepared for electron microscopic investigation, the other half for bioassay. Fixation using collidine buffered osmium tetroxide was followed by dehydration and embedment in Maraglas. Uranyl acetate and lead citrate were used as stains. Thin sections were examined in a Philips EM 200.Somatotrophs from uninjected controls appeared as described in the literature (Fig. 1). In addition to other components, these cells contained moderate numbers of spherical, electron-dense, membrane-bound granules approximately 350 millicrons in diameter.

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