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.

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.

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.

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.

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.

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.

scholarly journals Electron microscopic immunoperoxidase staining of insulin using 4-chloro-1-naphthol after osmium fixation.

1982 ◽  
Vol 30 (7) ◽  
pp. 710-712 ◽  
Author(s):  
D G Baskin ◽  
H Mar ◽  
K C Gorray ◽  
W Y Fujimoto
Keyword(s):  
Osmium Tetroxide ◽  
Ultrastructural Localization ◽  
Uranyl Acetate ◽  
Immunoperoxidase Staining ◽  
Lead Citrate ◽  
Electron Microscopic ◽  
Specific Staining ◽  
Fixed Tissue ◽  
Substrate Solution ◽  
Peptide Antigens

Ultrastructural localization of insulin in B cells of guinea pig pancreas was accomplished after osmium fixation with an immunoperoxidase procedure that utilized 4-chloro-1-naphthol (CN) in the substrate solution. The principal features of this protocol were: a) osmium tetroxide postfixation; b) omission of hydrogen peroxide "etching"; c) use of CN instead of diaminobenzidine in the substrate solution; d) elimination of osmium tetroxide after the substrate reaction; e) uranyl acetate and lead citrate counterstaining. This procedure produces intense specific staining with low background using highly dilute antiserum, and appears to be useful for postembedding immunoperoxidase staining of a variety of peptide antigens in osmium-fixed tissue.

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 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.

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