Permeability in the Blood-Brain Barrier in Monkeys Following Exposure to High Altitude

1971 ◽  
Vol 29 ◽  
pp. 328-329
Author(s):  
R.S. Demaree ◽  
L.J. Ackerman ◽  
D. L. Anderson
Keyword(s):  
Electron Microscopy ◽  
Cerebral Edema ◽  
Osmium Tetroxide ◽  
Acute Mountain Sickness ◽  
Cebus Apella ◽  
Uranyl Acetate ◽  
Lead Citrate ◽  
Limited Evidence ◽  
Ultrathin Sections ◽  
Mountain Sickness

People who rapidly ascend to high terrestrial elevations may experience the “acute mountain sickness” syndrome. Speculation and limited evidence suggest that cerebral edema may play an important role in initiating and perpetuating this condition. We have recently demonstrated by electron microscopy that a mild cerebral edema develops in some Cebus apella monkeys rapidly transported to 14,110 feet. In the present study, Cebus apella monkeys were terminated at 1, 3, or 5 days after being shipped from sea level (160 feet) to 14,110 feet without acclimatization at intermediate altitudes.Thorotrast was administered IV 30 minutes prior to termination by perfusion or guillotine. Cerebral cortex was fixed by either perfusion or immersion in glutaraldehyde, and postfixed in osmium tetroxide. Following fixation, the tissues were dehydrated in ascending concentrations of ethanol followed by propylene oxide and embedded in Epon 812. Ultrathin sections were either not stained or doubly stained with uranyl acetate and lead citrate.

Ultrastructure of Angiosarcoma of Mouse Tail

1980 ◽  
Vol 38 ◽  
pp. 740-741
Author(s):  
White Yvonne ◽  
Winslow Sheldon ◽  
James W. Townsend ◽  
Neil A. Littlefield
Keyword(s):  
Electron Microscopy ◽  
Electron Microscope ◽  
Light Microscopy ◽  
Toluidine Blue ◽  
Female Mouse ◽  
Osmium Tetroxide ◽  
Uranyl Acetate ◽  
Lead Citrate ◽  
Ultrathin Sections ◽  
Resin Mixture

Spontaneous neoplasms rarely occur on the tails of BALB/cStCrlfC3H/Nctr mice, but the neoplasm most frequently observed is a locally invasive non-metastatic angiosarcoma. In this case a female mouse weighing 33.2 g, 706 days of age, presented a soft, red, irregularly-shaped mass, measuring 18 mm in its greatest dimension, in the subcutis of the base of the tail. A portion of the tail tumor was taken for electron microscopy and the remainder was processed for light microscopy. The tissue processed for electron microscopy was fixed in 4% cacodyl ate-buffered glutaraldehyde, post-fixed in 1% osmium tetroxide, dehydrated in a graded series of ethanol solutions, and embedded in Epon-Araldite resin mixture. Sections of 1 μm were stained with toluidine blue for light microscopy and ultrathin sections of 100 nm were stained with uranyl acetate and lead citrate, then examined with a Philips EM201 electron microscope .

X-ray microanalytical and enzyme-cytochemical study on vesical malacoplakia

1978 ◽  
Vol 36 (2) ◽  
pp. 646-647
Author(s):  
Masami Hokano ◽  
Tsunao Oh-I ◽  
Yoshie Narita ◽  
Hiroshi Sassa ◽  
Saburo Suzuki
Keyword(s):  
Electron Microscopy ◽  
Electron Microscope ◽  
Osmium Tetroxide ◽  
Granulomatous Inflammation ◽  
Uranyl Acetate ◽  
The Other ◽  
Lead Citrate ◽  
Cytochemical Study ◽  
X Ray ◽  
Ultrathin Sections

Malacoplakia is a kind of granulomatous inflammation and characterized by the presence of calcium-stain positive granules (Michaelis-Gutmann bodies, hereinafter abbreviated as M-G bodies ) in the macrophages.In this report we want to say about the following articles:the ultrastruc tural findings in four cases of vesical malacoplakia;the ultrastructural morphogenesis of the M-G bodies;X-ray microanalytical studies which examine the change of the chemical component of M-G bodies, according to their developing stages; andacid phosphatase activity of lysosome within the malacoplakic macrophages.Biopsy materials taken from four cases with vesical malacoplakia were divided into 2 parts; one for a light microscopy and the other for an electron microscopy. The specimen for an electron microscopy was fixed in glutaraldehyde and osmium tetroxide, dehydrated in ethanol and then embedded in Epon 812. Ultrathin sections were doublestained with lead citrate and uranyl acetate and then subjected to routin TEM observation. For X-ray microanalysis was mounted an energy dispersive X-ray microanalyzer on a JEM-100 C type electron microscope. Ultrathin sections for microanalysis were cut 100-200nm thich and not stained.

Electron microscopy of the changes in the sperm head curvature of the palm squirrel (Funambulus Penanti)

1993 ◽  
Vol 51 ◽  
pp. 334-335
Author(s):  
S. R. Bawa ◽  
R. Bawa ◽  
H. K. Bains
Keyword(s):  
Electron Microscopy ◽  
Plasma Membrane ◽  
Electron Microscope ◽  
Osmium Tetroxide ◽  
Uranyl Acetate ◽  
Sperm Head ◽  
Lead Citrate ◽  
Transmission Electron ◽  
Ultrathin Sections ◽  
Epididymal Spermatozoa

Examination of ultrathin sections of the spermatozoa recovered from the epididymis of the Indian palm squirrel (Funambulus penanti) indicates that the sperm head undergoes changes in its curvature during epididymal transit.Testis and epididymis of an adult male squirrel were dissected and small pieces of tissue fixed in 2.0% glutaraldehyde in 0.1 M phosphate buffer and post-fixed in osmium tetroxide. After dehydration in graded acetone the material was embedded in Araldite. Ultrathin sections were cut on a Reichert Jung Ultracut, picked-up on copper grids, stained with Reynold’s lead citrate-uranyl acetate and examined with a JEOL 1200 EX transmission electron microscope.Ultrathin sections of the caput epididymal spermatozoa reveal that their plasma membrane is adherent to the underlying acrosome (Figure 1). When these spermatozoa reach the corpus epididymis the plasma membrane surrounding the head becomes ruffled (Figure 2). The lifting-up of the plasma membrane around the head is restricted to the posterior bend of the acrosome.

The Identification of Phospholipid Micelles in Glutaraldehyde-Urea Embedded Tissue

1975 ◽  
Vol 33 ◽  
pp. 494-495
Author(s):  
Daniel C. Pease
Keyword(s):  
Electron Micrographs ◽  
Lung Tissue ◽  
Osmium Tetroxide ◽  
Uranyl Acetate ◽  
Type Ii ◽  
Lead Citrate ◽  
Phospholipid Micelles ◽  
Type Ii Pneumocytes ◽  
Ultrathin Sections ◽  
Polar Water

It is reasonable to think that phospholipid micelles should be visible and identifiable in electron micrographs of ultrathin sections if only they can be preserved throughout the embedding process. The development of highly polar, water-containing, aminoplastic embedments has made this a likely possibility. With this in mind, an investigation of the lecithin-secreting, Type II pneumocytes of the lung is underway.Initially it has been easiest to recognize phospholipid micelles in lung tissue fixed first with glutaraldehyde, and then secondarily exposed to osmium tetroxide. However, the latter is not a necessary concomitant for micellar preservation. Conventional uranyl acetate and lead citrate staining is finally applied. Importantly, though, the micelles have been most easily seen in tissue embedded in 507. glutaraldehyde polymerized with urea, as described in detail by D.C. Pease and R.G. Peterson (J. Ultra- struct. Res., 41, 133, 1972). When oriented appropriately, the micellar units are seen as tiny, bilayer plates.

Electron Microscopy of Wound Healing in Patients with Hernia

1975 ◽  
Vol 33 ◽  
pp. 352-353
Author(s):  
C.N. Sun ◽  
H.J. White ◽  
R.C. Read
Keyword(s):  
Electron Microscopy ◽  
Wound Healing ◽  
Phosphate Buffer ◽  
Osmium Tetroxide ◽  
Phosphotungstic Acid ◽  
Rectus Sheath ◽  
Uranyl Acetate ◽  
Collagen Fibrils ◽  
Lead Citrate ◽  
Native Collagen

Previously we have reported the defect of collagen fibrils from herniated rectus sheath. This presentation includes additional sections from postsurgical incisions (10 days) from both control and hernia patients. Small pieces of rectus sheath were fixed in 3% glutaraldehyde in phosphate buffer (pH 7.2) and post fixed with buffered 2% osmium tetroxide. The tissues were then dehydrated in serially increasing concentrations of alcohol and embedded in Epon 812. Sections were stained with 2.5% phosphotungstic acid or uranyl acetate and lead citrate.Previously we found that collagen fibrils from "non-herniated" rectus sheath have uniform diameters and 640 Å periodicity with seven or more intraperiodic bands resembling typical native collagen fibrils, while the fibrils from fascia obtained from patients with direct herniation show considerable variation in diameter. These variations are often found in the same individual fibers with a range from 300 Å to 3000 Å.

A Modified Technic of Staining Elastic Tissue for Electron Microscopic Study

1975 ◽  
Vol 33 ◽  
pp. 626-627
Author(s):  
J.A. Nordquist ◽  
K. Chrysant ◽  
A.K. Mandal
Keyword(s):  
Electron Microscopy ◽  
Osmium Tetroxide ◽  
Renal Tissue ◽  
Uranyl Acetate ◽  
Elastic Tissue ◽  
Lead Citrate ◽  
Electron Microscopic ◽  
Modified Method ◽  
Tetraphenyl Porphyrin ◽  
Normal Rat

By electron microscopy elastic tissue appear electrolucent in osmium fixed unstained grids as well as grids stained with uranyl acetate and lead citrate (UA + LC). Albert and Fleischer have studied aorta of mice with metalloporphyrins imparting conspicuous electron density to the elastic tissue. We are reporting here a modified method of electron microscopic (EM) study of the elastic tissue using metalloporhyrin, silver tetraphenyl porphyrin sulfonate (STPPS).We have studied the renal arterioles of rats and human in normal and diseased states. Elastic tissue of the aorta from young normal rat served as control for this study. Renal and aortic tissues were fixed in 4 percent glutaraldehyde, post fixed in 1 percent osmium tetroxide and embedded in spurr (blocks). From the blocks of renal tissue, 0.5 μ sections were cut, stained with methylene blue and azure II and studied by light microscopy.

Uranyl Acetate as a Fixative—from pH 2.0 to 8.0

1971 ◽  
Vol 29 ◽  
pp. 490-491
Author(s):  
V. R. Mumaw ◽  
B. L. Munger
Keyword(s):  
Electron Microscopy ◽  
Oxalic Acid ◽  
Osmium Tetroxide ◽  
Uranyl Acetate ◽  
En Bloc ◽  
Tissue Sections ◽  
Normal Rat ◽  
Lead Hydroxide ◽  
Ultrathin Sections ◽  
Rat Tissue

Numerous applications utilizing uranyl acetate as an electron stain for electron microscopy have been described. Uranyl acetate has become a routine stain used in conjunction with lead hydroxide for staining ultrathin sections. En bloc staining with uranyl acetate following osmium tetroxide post-fixation produces undesirable effects on some cytoplasmic components, especially glycogen. Recent studies using uranyl acetate as a fixative and en bloc stain at pH 7.2 before osmification has shown uranyl acetate to have desirable fixation and staining qualities. Tissues treated with uranyl acetate at a pH of 2.0-8.0 were studied. Normal rat tissue was fixed in Karnovsky's paraformaldehyde-glutaraldehyde fixative. The tissue was post-fixed in 0.5% uranyl acetate in water at pH 2.0 and 0.5% uranyl acetate in 0.1M s-collidine with 0.01M oxalic acid at pH 4, pH 6.0, pH 7.2, and pH 8.0 for 1 hour at 4°C. Following several rinses of 0.1M s-collidine buffer, the tissues were treated with 1.33% osmium tetroxide 1 hour at 4°C followed by rapid dehydration in ethanol and embedded in Durcupan ACM. Tissue sections were stained with lead hydroxide.

The Development of the Outer Plexiform Layer of the Mouse Retina

1972 ◽  
Vol 30 ◽  
pp. 56-57
Author(s):  
Janet C. Blanks ◽  
Anthony M. Adinolfi ◽  
Richard N. Lolley
Keyword(s):  
Electron Microscopy ◽  
Osmium Tetroxide ◽  
Adult Mouse ◽  
Light And Electron Microscopy ◽  
Plexiform Layer ◽  
Uranyl Acetate ◽  
Bipolar Cells ◽  
Outer Plexiform Layer ◽  
Mouse Retina ◽  
Lead Citrate

In the all-rod retina of the adult mouse, synaptic contacts in the outer plexiform layer occur between photoreceptor terminals and dendritic processes of horizontal and bipolar cells. The postnatal development of the outer plexiform layer has been studied by light and electron microscopy. Following decapitation and enucleation of the eyes, samples of retinae from DBA mice (newborn to fourteen days) were removed and fixed by immersion in solutions of buffered glutaraldehyde and paraformaldehyde. The tissue was postfixed in osmium tetroxide, dehydrated and embedded in araldite. Sections were stained with uranyl acetate and lead citrate.With light microscopy, the outer plexiform layer first appears in the central retina as a gap within the neuroblastic layer on the fifth postnatal day. The separation is completed by the seventh postnatal day and appears mature by the fourteenth postnatal day.

scholarly journals EVIDENCE FOR CHANGES IN PROTEIN POLYSACCHARIDE ASSOCIATED WITH THE ONSET OF CALCIFICATION IN CARTILAGE

1968 ◽  
Vol 39 (1) ◽  
pp. 43-48 ◽  
Author(s):  
Victor J. Matukas ◽  
George A. Krikos
Keyword(s):  
Electron Microscopy ◽  
Osmium Tetroxide ◽  
Marked Decrease ◽  
Uranyl Acetate ◽  
Lead Citrate ◽  
Electron Microscopic ◽  
Calcified Cartilage ◽  
The Matrix ◽  
Microscopic Studies ◽  
Matrix Components

Past work has suggested that protein polysaccharide may play a role in the calcification of cartilage. Recent electron microscopic studies on noncalcified cartilage have indicated that protein polysaccharide in cartilage matrix is represented by granules associated with collagen fibers. The present work has been designed for comparison of the matrix of noncalcified cartilage to that of calcified cartilage, with particular reference to these granules. Small blocks of tibia from 16-day embryos were fixed in cacodylate-buffered glutaraldehyde and postfixed in either phosphate- or Veronal-buffered osmium tetroxide. Special care was taken to maintain the pH above 7.0 at all times. For electron microscopy the tissues were dehydrated, embedded in Epon 812, sectioned, and stained with uranyl acetate or lead citrate. A marked decrease in the size of granules in the matrix of calcified cartilage compared to noncalcified cartilage was noted. Associated with the decrease in the size of granules was a condensation of matrix components and the presence of an amorphous electron-opaque material that was not seen in noncalcified areas. These results are interpreted to represent either a drop in concentration or a change in state of protein polysaccharide with the onset of calcification in cartilage.

scholarly journals HYDROXYPROPYL METHACRYLATE, A NEW WATER-MISCIBLE EMBEDDING MEDIUM FOR ELECTRON MICROSCOPY

1965 ◽  
Vol 26 (1) ◽  
pp. 137-155 ◽  
Author(s):  
Elizabeth H. Leduc ◽  
S. J. Holt
Keyword(s):  
Electron Microscopy ◽  
Osmium Tetroxide ◽  
Uranyl Acetate ◽  
Rat Tissues ◽  
Enzymatic Extraction ◽  
Hydroxypropyl Methacrylate ◽  
Ultrathin Sections ◽  
Heat Polymerization ◽  
Embedding Medium ◽  
Fasted Rats

Aldehyde-fixed rat tissues were variously dehydrated and impregnated in water-miscible 2-hydroxypropyl methacrylate (HPMA) containing 3 to 20 per cent water and 0.1 per cent α,α-azobisisobutyronitrile as catalyst for subsequent polymerization with ultraviolet light. Heat polymerization was also effective. Blocks of embedded tissue readily gave ultrathin sections, which required staining by uranyl acetate and/or lead stains to give adequate contrast for electron microscopy. The ultrastructure of pancreas, kidney, muscle, and intestine was well preserved by aldehyde fixation alone. Use of postfixation in osmium tetroxide or direct osmium tetroxide fixation was unsatisfactory. The fine structure of aldehyde-fixed liver from fasted rats was well preserved, whereas that from normal rats showed considerable disorganization and collapse, apparently because of extraction of glycogen during the embedding procedure. Enzymatic extraction of proteins by pepsin and of ribonucleic acid by ribonuclease after either formaldehyde or glutaraldehyde fixation was rapidly effected by direct treatment of ultrathin sections with solutions of the enzymes. In contrast, no digestion of chromatin by deoxyribonuclease could be detected. In spite of this present limitation, HPMA appears to have several advantages over earlier water-miscible embedding media for electron microscopy and to be particularly suitable for ultrastructural cytochemistry.

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