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.

Platinum Compounds as Stains for Electron Microscopy

1974 ◽  
Vol 32 ◽  
pp. 230-231
Author(s):  
S. K. Aggarwal ◽  
P. McAllister ◽  
R. W. Wagner ◽  
B. Rosenberg
Keyword(s):  
Electron Microscopy ◽  
Hela Cells ◽  
Uranyl Acetate ◽  
Sarcoma 180 ◽  
Platinum Compounds ◽  
Kb Cells ◽  
En Bloc ◽  
Human Lymphoma ◽  
Ultrathin Sections ◽  
Blue Coloration

Uranyl acetate has been used as an electron stain for en bloc staining as well as for staining ultrathin sections in conjunction with various lead stains (Fig. 1). Present studies reveal that various platinum compounds also show promise as electron stains. Certain platinum compounds have been shown to be effective anti-tumor agents. Of particular interest are the compounds with either uracil or thymine as one of the ligands (cis-Pt(II)-uracil; cis-Pt(II)-thymine). These compounds are amorphous, highly soluble in water and often exhibit an intense blue coloration. These compounds show enough electron density to be used as stains for electron microscopy. Most of the studies are based on various cell lines (human AV, cells, human lymphoma cells, KB cells, Sarcoma-180 ascites cells, chick fibroblasts and HeLa cells) while studies on tissue blocks are in progress.

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.

Electron Microscopy as an aid to diagnosis in pediatric hematology/oncology

1989 ◽  
Vol 47 ◽  
pp. 1062-1063
Author(s):  
K. L. Saving ◽  
R. C. Caughey
Keyword(s):  
Electron Microscopy ◽  
Phosphate Buffer ◽  
Osmium Tetroxide ◽  
Uranyl Acetate ◽  
En Bloc ◽  
Thin Sections ◽  
Megakaryoblastic Leukemia ◽  
Pediatric Hematology ◽  
Transmission Electron ◽  
Microscopy Techniques

This presentation is designed to demonstrate how scanning and transmission electron microscopy techniques can be utilized to confirm or support a variety of unusual pediatric hematologic/oncologic disorders. Patients with the following diagnoses will be presented: (1) hereditary pyropoikilocytosis, (2) familial erythrophagocytic lymphohistiocytosis, (3) acute megakaryoblastic leukemia, and (4) pseudo-von Willebrand’s disease.All transmission and scanning electron microscopy samples were fixed in 2.5% glutaraldehyde, rinsed in Millonig’s phosphate buffer, and post-fixed with 1% osmium tetroxide. The transmission samples were then en bloc stained with 0.5% uranyl acetate, rinsed with Walpole ’ s non-phosphate buffer, dehydrated with graded series of ethanols and embedded with Epon 812 epoxy resin. Ultramicrotomy thin sections were stained with uranyl acetate and lead citrate and scanned using a JEOL-JEM 100C, The scanning samples were dehydrated with graded series of ethanols, critical point dried with CO2, gold-coated, and scanned using a JEOL-JSM 35. The peroxidase samples were fixed in 3% glutaraldehyde, incubated in diaminobenzidine (DAB), dehydrated with ethanol, embedded with Epon 812, and scanned without post-staining using a JEOL-JEM 100C.

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 .

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.

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.

Cellular Contacts Within the Interhemal Membrane of the Rat Placenta at Term

1974 ◽  
Vol 32 ◽  
pp. 146-147
Author(s):  
William P. Jollie
Keyword(s):  
Osmium Tetroxide ◽  
Uranyl Acetate ◽  
Capillary Endothelium ◽  
En Bloc ◽  
Aldehyde Fixation ◽  
Chorioallantoic Placenta

By routine EM preparative techniques, the tissues which, collectively, separate maternal and fetal bloods in the fully formed chorioallantoic placenta of the rat have been shown to consist of three chorionic layers, or trophoblast, and a layer of allantoic capillary endothelium [Fig. 1]. Relationships between these layers are best demonstrated by special techniques, viz., cacodylate-buffered aldehyde fixation, collidine-buffered osmium tetroxide postfixation, and en bloc staining with uranyl acetate. By using this method on placentas at term, the cells of the outermost chorionic layer (Trophoblast 1) appear to be attached to each other by means of maculae adherentes which sometimes occur in clusters [Fig. 2].

The Ultrastructure of Metastatic Human Mammary Carcinoma After Prolonged Estrogen Therapy

1967 ◽  
Vol 25 ◽  
pp. 180-181
Author(s):  
John H.L. Watson ◽  
John L. Swedo ◽  
R.W. Talley
Keyword(s):  
Mammary Carcinoma ◽  
Osmium Tetroxide ◽  
Estrogen Therapy ◽  
Ultrastructural Level ◽  
Uranyl Acetate ◽  
Human Mammary Carcinoma ◽  
Surgical Biopsy ◽  
Lead Hydroxide ◽  
Preliminary Study ◽  
Hormonal Therapies

A preliminary study of human mammary carcinoma on the ultrastructural level is reported for a metastatic, subcutaneous nodule, obtained as a surgical biopsy. The patient's tumor had responded favorably to a series of hormonal therapies, including androgens, estrogens, progestins, and corticoids for recurring nodules over eight years. The pertinent nodule was removed from the region of the gluteal maximus, two weeks following stilbestrol therapy. It was about 1.5 cms in diameter, and was located within the dermis. Pieces from it were fixed immediately in cold fixatives: phosphate buffered osmium tetroxide, glutaraldehyde, and paraformaldehyde. Embedment in each case was in Vestopal W. Contrasting was done with combinations of uranyl acetate and lead hydroxide.

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