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.

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.

scholarly journals AN ELECTRON MICROSCOPIC STUDY OF NUCLEAR ELIMINATION FROM THE LATE ERYTHROBLAST

1967 ◽  
Vol 33 (3) ◽  
pp. 625-635 ◽  
Author(s):  
Ehud Skutelsky ◽  
David Danon
Keyword(s):  
Bone Marrow ◽  
Osmium Tetroxide ◽  
Mitotic Division ◽  
Uranyl Acetate ◽  
Lead Citrate ◽  
Electron Microscopic ◽  
Thin Sections ◽  
Whole Process ◽  
Narrow Passage ◽  
Rounded Form

The process of expulsion of the nucleus during the transformation of the late erythroblast to reticulocyte is described. Erythroid clones taken from the spleen of lethally irradiated mice transplanted with syngeneic bone marrow were used. 10–12-day old isolated clones were fixed in glutaraldehyde, then in osmium tetroxide. Ultra-thin sections were stained with uranyl acetate and/or lead citrate before examination. Late (orthochromatic) erythroblasts develop pseudopod-like cytoplasmic protrusions into one of which the nucleus gradually penetrates, being deformed by the extrusion through the relatively narrow passage. During the whole process, mitochondria and vesicular and membranous elements are concentrated in the cytoplasm. Once outside the cell, the nucleus reassumes its rounded form. It is surrounded by a narrow rim of cytoplasm and structurally altered plasma membrane and is connected to the rest of the cell by a bridge. Elongated vacuoles appear within this bridge, with a resulting release of the enveloped nucleus which is soon phagocytized by macrophages; this leaves behind the newly formed reticulocyte. During this process, the cytoplasmic protrusions, the agglomeration of mitochondria, and the mode of separation of the nucleus from the rest of the cell are similar to those occurring in mitotic division.

scholarly journals An Electron Microscopic Investigation into the Effect of EDTA on Plant Cell Wall

1960 ◽  
Vol 7 (2) ◽  
pp. 335-338 ◽  
Author(s):  
Shimon Klein ◽  
B. Ginzburg
Keyword(s):  
Cell Wall ◽  
Plant Cell Wall ◽  
Microscopic Investigation ◽  
Uranyl Acetate ◽  
Electron Microscopic Investigation ◽  
Wall Structure ◽  
Acetate Solution ◽  
Root Tips ◽  
Electron Microscopic ◽  
Thin Sections

To study the effect of EDTA on cell wall structure and the reversal of this effect by uranyl ion, thin sections of pea root tips were examined in the electron microscope. EDTA is known to facilitate separation of the cells in root tips. When sections of fixed and embedded EDTA-treated roots are floated on a uranyl-acetate solution, a loose network is revealed that would seem to be cellulose. Incorporation of uranyl into the roots, if it occurs prior to fixation, brings about recementation of the cells. After such treatment, a marginal darker area and a median brighter one can be observed in the wall, and the whole structure appears more compact again. Comparison of the results of the various treatments suggests that cellulose-cementing material is dispersed throughout the entire wall, and that its distribution parallels that of cellulose.

Membranous alterations in the cytoplasm and nucleus in a primitive neuroectodermal tumor of the brain

1978 ◽  
Vol 36 (2) ◽  
pp. 628-629
Author(s):  
C. N. Sun ◽  
C. Araoz ◽  
H. J. White
Keyword(s):  
Nuclear Envelope ◽  
Tumor Cells ◽  
Osmium Tetroxide ◽  
Primitive Neuroectodermal Tumor ◽  
Uranyl Acetate ◽  
Neuroectodermal Tumor ◽  
Annulate Lamellae ◽  
Lead Citrate ◽  
Thin Sections ◽  
The Brain

The ultrastructure of a cerebral primitive neuroectodermal tumor has been reported previously. In the present case, we will present some unusual previously unreported membranous structures and alterations in the cytoplasm and nucleus of the tumor cells.Specimens were cut into small pieces about 1 mm3 and immediately fixed in 4% glutaraldehyde in phosphate buffer for two hours, then post-fixed in 1% buffered osmium tetroxide for one hour. After dehydration, tissues were embedded in Epon 812. Thin sections were stained with uranyl acetate and lead citrate.In the cytoplasm of the tumor cells, we found paired cisternae (Fig. 1) and annulate lamellae (Fig. 2) noting that the annulate lamellae were sometimes associated with the outer nuclear envelope (Fig. 3). These membranous structures have been reported in other tumor cells. In our case, mitochondrial to nuclear envelope fusions were often noted (Fig. 4). Although this phenomenon was reported in an oncocytoma, their frequency in the present study is quite striking.

Fine Structural Classification of Chromophobe Adenomas of the Human Pituitary Gland

1975 ◽  
Vol 33 ◽  
pp. 378-379
Author(s):  
K. Kovacs ◽  
E. Horvath
Keyword(s):  
Pituitary Adenomas ◽  
Secretory Activity ◽  
Microscopic Investigation ◽  
Uranyl Acetate ◽  
Electron Microscopic Investigation ◽  
Electron Microscopic ◽  
Human Pituitary ◽  
Cytoplasmic Staining ◽  
Human Pituitary Gland ◽  
Microscopic Features

Chromophobe pituitary adenomas arise from adenohypophysial cells and fail to exhibit cytoplasmic staining with conventional acid or basic dyes by light microscopy. The aim of the present work was to study the electron microscopic features of these tumors, to separate them into distinct entities and to correlate their fine structural appearances with secretory activity.Among 48 surgically removed various pituitary adenomas 30 tumors were found which, based on the tinctorial characteristics of the cytoplasm, corresponded to chromophobe adenomas. For electron microscopic investigation pieces of these tumors were fixed in 2.5 per cent glutaraldehyde in Sorensen's buffer, post fixed in 1 per cent osmium tetroxide in Millonig's buffer, dehydrated in graded ethanol and embedded in Epon 812. Ultrathin sections were stained with uranyl acetate and lead citrate.By electron microscopy it was possible to separate chromophobe adenomas into 3 distinct entities: 1) adenomas consisting of sparsely granulated growth hormone cells (7 cases).

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.

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.

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.

Electron microscopic evidence for a double hair-like nap appearing at low frequency on Bacillus anthracis Sterne spores

1969 ◽  
Vol 15 (10) ◽  
pp. 1247-1248 ◽  
Author(s):  
M. J. Kramer ◽  
Ivan L. Roth
Keyword(s):  
Bacillus Anthracis ◽  
Microscopic Examination ◽  
Low Frequency ◽  
Electron Microscopic Examination ◽  
Uranyl Acetate ◽  
Spore Coat ◽  
Lead Citrate ◽  
Electron Microscopic ◽  
Thin Sections ◽  
Very Low Frequency

Electron microscopic examination of thin sections of Bacillus anthracis Sterne spores triply poststained with KMnO4, uranyl acetate, and lead citrate has indicated an unusual morphological variant. These spores are seen at very low frequency and have, in addition to the hair-like nap normally associated with the exosporium a second hairy layer which appears to originate in the spore coat complex.

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