Electron Microscopic Study of a Spontaneous Rat Tumor

1971 ◽  
Vol 29 ◽  
pp. 322-323
Author(s):  
P. W. Cole ◽  
R. M. Jamison
Keyword(s):  
Propylene Oxide ◽  
Uranyl Acetate ◽  
Female Rat ◽  
Lead Citrate ◽  
Sprague Dawley ◽  
Electron Microscopic ◽  
Non Invasive ◽  
Ultrathin Sections ◽  
Glass Knife ◽  
Rat Tumor

A spontaneously occurring, non-invasive mammary tumor was observed in a 7-month-old, non-lactating, random-bred Sprague-Dawley female rat. The tumor was located subcutaneously in the distal mammary line as a firmly encapsulated, lobated growth. The tumor was surgically removed and immersed in Clark's buffer containing 4% glutaraldehyde. (Later conventional histochemical studies revealed this tumor to be a relatively non-differentiated fibro-adenoma.) Exterior and interior portions of the tumor were excised and fixed separately. The tissues were cut into 1 mm cubes and fixed for 4 hours in 4% glutaraldehyde. The specimens were then washed 4 times in buffer and left overnight at 4°C in the buffer. The cubes were postfixed in 2% OsO4 for 2 hours, after which they were dehydrated in a graded series of ethanol. The specimens were then washed with 2 changes of propylene oxide and perfused with a 1:1 mixture of propylene oxide-Epon 812 for 1 hour. Next, the tissue cubes were embedded in a mixture of Epon 812, DDSA, NMA, and DMP 30. Polymerization was allowed to proceed sequentially at 37°C overnight, 45°C for 8 hours, and 60°C for 24 hours. Ultrathin sections were cut with the Porter-Blum MT-2B ultramicrotome equipped with a glass knife. Sections were picked up on copper grids and stained with saturated uranyl acetate and 0.2% lead citrate. Specimens were examined in the Philips 300 electron microscope at instrumental magnifications ranging from 3,000-20,000 times.

The fine structure of ascus development in Lasiobolus monascus (Pezizales)

1978 ◽  
Vol 56 (7) ◽  
pp. 862-872 ◽  
Author(s):  
James W. Kimbrough ◽  
Gerald L. Benny
Keyword(s):  
Fine Structure ◽  
Uranyl Acetate ◽  
Microscopic Level ◽  
Electron Microscopic Level ◽  
Stalk Cell ◽  
Lead Citrate ◽  
Electron Microscopic ◽  
Ultrathin Sections ◽  
Microscopic Inspection ◽  
Physical And Chemical

Ultrastructural and cytochemical studies on the ascus of Lasiobolus monascus are presented. Apothecia in various stages of development were obtained in culture and prepared for both light and electron microscopic observations. Ultrathin sections for electron microscopic inspection were often treated with silver methenamine to enhance wall characteristics. Ascus development was followed from fertilization to maturity.In this species, the ascogonium enlarges after fertilization to become the ascus mother cell. Two pores are present in the young ascus, one connecting it to the antheridium and another between the ascus and stalk cell. The ultrastructural features of these pores in the young and maturing ascus are described. During ascus enlargement, as many as four wall layers are found when poststained with silver methenamine. Only two layers are clearly distinguishable when poststained with uranyl acetate and lead citrate. The apical zone of dehiscence is characterized by a distinct annular swelling which appears during early ascosporogenesis. By spore maturation, this swelling is not evident either at the light or electron microscopic level. Instead, there appear to be both physical and chemical changes in the area of dehiscence. The wall is distinctly thinner and much more electron transparent in the area of dehiscence when treated with silver methanamine.

Electron microscopic study on the phagocytic lining cells in the cavernous body of the lamprey gill

1978 ◽  
Vol 36 (2) ◽  
pp. 448-449
Author(s):  
Kazuhito Yamaguchi ◽  
Kazuhiko Awaya
Keyword(s):  
Electron Microscope ◽  
Uranyl Acetate ◽  
Osmic Acid ◽  
Lead Citrate ◽  
Electron Microscopic ◽  
Embedded Blocks ◽  
Ultrathin Sections ◽  
Branchial Artery ◽  
Scanning Electron ◽  
Cavernous Body

The lining cells in the cavernous body, which is a branch of the afferent branchial artery, of lamprey gills were studied with transmission (TEM) and scanning electron microscope (SEM).Adult and larval lampreys, Lampertra planeri, were used in this study. Lamprey gills removed after perfusion were fixed in 2 % glutaraldehyde/formaldehyde (pH 7. 4) for 1 hour and postfixed in 1 % osmic acid. For TEM, the gills were dehydrated in ethanol and embedded in epon 812. Ultrathin sections were doubly stained with uranyl acetate and lead citrate. For SEM, most of the gills were dehydrated in ethanol and isoamylacetate and cracked in liquid nitrogen. Some of the gills dehydrated were embedded in stylene monomer. Stylene embedded blocks were cracked with a hummer and dissolved in propylene oxide. All the specimens were dried in a critical point dryer and coated 100 Å thickness with gold-paladium.The cavernous body is composed of trabeculae, between which are blood spaces, the lacunae.

Ultrastructure of the Ascospores and Conidia of Venturia Inaequalis

1973 ◽  
Vol 31 ◽  
pp. 466-467
Author(s):  
A. L. Granett
Keyword(s):  
Osmium Tetroxide ◽  
Venturia Inaequalis ◽  
Uranyl Acetate ◽  
Distilled Water ◽  
Lead Citrate ◽  
Electron Microscopic ◽  
Apple Leaves ◽  
Ultrathin Sections ◽  
Ultrastructural Characteristics ◽  
Microscopic Investigations

Venturia inaequalis (Cke.) Wint. is the causal agent of scab,a worldwide disease of apples. There have been few electron microscopic investigations on any phase of this fungus. The studies reported herein were initiated to clarify some ultrastructural characteristics of ascospores and conidia.In the spring ascospores develop within perithecia on decaying apple leaves from the previous year. Either whole perithecia were teased from leaves, or ascospores were isolated from leaves in an air tunnel device. Conidia develop on living leaves, blossoms, and fruits. Infected leaves were sprayed with distilled water and these spores were collected and concentrated into a pellet by low speed centrifugation. Perithecia, ascospores, and conidia were fixed in glutaraldehyde and osmium tetroxide; ultrathin sections were stained with uranyl acetate and lead citrate.

Ultrastructural characteristics on capillary of giant panda

1990 ◽  
Vol 48 (3) ◽  
pp. 491-491
Author(s):  
Zeng Xiang-Yuan ◽  
Chong Hang ◽  
Lian Wei ◽  
Zhang Ke-juing
Keyword(s):  
Microscopic Observation ◽  
Giant Panda ◽  
Electron Microscopic Observation ◽  
Uranyl Acetate ◽  
Osmic Acid ◽  
Lead Citrate ◽  
Capillary Diameter ◽  
Electron Microscopic ◽  
Ultrathin Sections ◽  
Ultrastructural Characteristics

Electron microscopic observation on ultrastructural characteristics of the capillary ofgiant panda was presented. The samples were taken from mesentery and another samples were taken from mucosa of intestine. They were fixed in 2.5% phosphatebuffered glutaraldehyde and 1% osmic acid, and dehydrated by graded series of acetone. Then they were embedded with Epon 812. For orientation under phasecontrast microscope, 0.5--1.0 u thick sections were prepared from the epoxyembedded material. After that, ultrathin sections (30-50) were taken with ultramicrotome LKB-V type and stained by uranyl acetate and lead citrate and examined under DXB2-12 Electron Microscope.Electron microscopic observation showed the capillary diameter in the mesentery microcirculation is larger and capillary wall is thin. The nucleus in endothelium was large and wasn't regular in the shape. Chromatin was loose in the nucleus. There was little plasma inthe endothelium and it looked loose. Organelles in the cytoplasm were little and vacuoles were more in endothelium. The distribution of plasma in the endothelium was different with endothelium of human body.

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.

Electron Microscopic Examination of a Transplantable Rat Mammary Carcinoma

1968 ◽  
Vol 26 ◽  
pp. 20-21
Author(s):  
S. Shirahama ◽  
G. C. Engle ◽  
R. M. Dutcher
Keyword(s):  
Electron Microscope ◽  
Osmium Tetroxide ◽  
Electron Microscopic Examination ◽  
Undifferentiated Carcinoma ◽  
Uranyl Acetate ◽  
Sprague Dawley ◽  
Electron Microscopic ◽  
North West ◽  
X Irradiation ◽  
Tissue Specimens

A transplantable carcinoma was established in North West Sprague Dawley (NWSD) rats by use of X-irradiation by Engle and Spencer. The tumor was passaged through 63 generations over a period of 32 months. The original tumor, an adenocarcinoma, changed into an undifferentiated carcinoma following the 19th transplant. The tumor grew well in NWSD rats of either sex at various ages. It was invariably fatal, causing death of the host within 15 to 35 days following transplantation.Tumor, thymus, spleen, and plasma from 7 rats receiving transplants of tumor at 3 to 9 weeks of age were examined with an electron microscope at intervals of 8, 15, 22 and 30 days after transplantation. Four normal control rats of the same age were also examined. The tissues were fixed in glutaraldehyde, postfixed in osmium tetroxide and embedded in Epon. The plasma was separated from heparanized blood and processed as previously described for the tissue specimens. Sections were stained with uranyl acetate followed by lead citrate and examined with an RCA EMU-3G electron microscope.

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.

Fine structural morphology of immunocytes of some molluscs and insects

1990 ◽  
Vol 48 (3) ◽  
pp. 386-387
Author(s):  
S.G. Pal ◽  
G. Baur ◽  
B. Ghosh ◽  
S. Palit ◽  
S. Modak ◽  
...  
Keyword(s):  
Blood Cells ◽  
Phosphate Buffer ◽  
Room Temperature ◽  
Structural Information ◽  
Uranyl Acetate ◽  
Meretrix Meretrix ◽  
Lead Citrate ◽  
Bivalve Molluscs ◽  
Structural Morphology ◽  
Ultrathin Sections

In recent years some of the blood cells of several molluscs and insects are characterised as immunocytes. Similar cells from a few invertebrates from India have been looked into under conventional TEM to register the ultrastructural features. This type of study is first of its kind in the subcontinent. Immunocytes from bivalve molluscs Meretrix meretrix, Laroellidens marqinalis and two insect species, apterygote Ctenolepism a longicaudata and pterygote Gesonula punctifrons provide a new set of fine structural information which forms a basis of comparison with those studied earlier.Immunocytes have been collected from the fresh live species of bivalve molluscs and insects obtained locally at Calcutta. These were fixed in icecold 2% glutaraldehyde in 0.1M phosphate buffer (pH 7.2-7.4) for 1-2 hours at 4-5°C. Subseguently pellets were post-osmicated in 1% OsO4 at room temperature for 1-2 hours. Following dehydration these were embedded in Araldite mixture in plastic capsules and polymerization was effected for 2 days at 60°C. Ultrathin sections were cut in a ultrotome and sections were double stained with Uranyl acetate and lead citrate. These were viewed in a TEM.

Immunohistochemical Identification and Electron Microscopic Study on Early Migrating Neural Crest Cells in the Chick Embryo

1997 ◽  
Vol 3 (S2) ◽  
pp. 177-178
Author(s):  
M. Monteagudo de la Rosa ◽  
M. González-Santander Martínez ◽  
G. Martinez Cuadrado ◽  
R. González Santander
Keyword(s):  
Neural Crest ◽  
Neural Tube ◽  
Early Stage ◽  
Neural Crest Cells ◽  
Uranyl Acetate ◽  
Electron Microscopic ◽  
Approaches To Study ◽  
Ultrathin Sections ◽  
Transient Structure ◽  
Immunohistochemical Identification

Just after neural fold fusion to form the neural tube, neural crest cells detach from the neural crest, a transient structure located in the dorsal region of the neural tube. Neural crest cells migrate and differentiate into many structures and cells. But the underlying controls of this detachment and initiation of emigration are unknown. Neural crest cells are usually not morphologically distinct from the adjacent neural epithelium (neural tube) and epidermal ectoderm (epiblast) flanking them. We are combining morphological and immunohistochemical approaches to study neural crest cells in their early stage of detachment from the neural crest.Hamburger and Hamilton (1951) stages 9 to 12 White Leghorn chick embryos. Fixation in 2.5% glutaraldehyde - 0.5% tanic acid and postfixation in 1% osmium tetroxide. Embryos contrasted in bloc using uranyl acetate and embedded in araldite. Semithin transversal sections stained with toluidine blue for light microscopy. Ultrathin sections contrasted with lead citrate.

An Electron Microscopic Investigation of the Pathogenesis of Hemorrhage Induced by Rattlesnake Venom

1974 ◽  
Vol 32 ◽  
pp. 56-57
Author(s):  
Charlotte L. Ownby ◽  
Robert A. Kainer ◽  
Anthony T. Tu
Keyword(s):  
Phosphate Buffer ◽  
Osmium Tetroxide ◽  
Microscopic Investigation ◽  
Uranyl Acetate ◽  
Electron Microscopic Investigation ◽  
Lead Citrate ◽  
Electron Microscopic ◽  
Thin Sections ◽  
Rattlesnake Venom ◽  
Diamondback Rattlesnake

One of the significant changes induced by the injection of rattlesnake (Crotalidae) venom is hemorrhage. Since crotaline antivenin does not prevent such local tissue damage, a more effective treatment of snakebite is needed. To aid in the development of such a treatment the pathogenesis of venom-induced hemorrhae was investigated.Swiss-Webster white mice were injected intramuscularly with Western diamondback rattlesnake (Crotalus atrox) venom. Two minutes after the injection, muscle tissue was obtained by bioosy from the thigh and fixed in 6% glutaraldehyde in Milloniq's phosphate buffer (DH 7.4, 2 hrs., 4°C). After post-fixation in 2% osmium tetroxide in Milloniq's phosphate buffer (pH 7.4, 1hr., 4°C) the tissue was dehydrated routinely in ethanol and embedded in Epon 812. The thin sections were stained with uranyl acetate in methanol and lead citrate then observed with either a Zeiss EM 9A or an Hitachi HS-8 electron microscope.

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