scholarly journals Variable opacity of glycogen in routine electron micrographs.

1977 ◽  
Vol 25 (9) ◽  
pp. 1069-1073 ◽  
Author(s):  
L E Thornell ◽  
M Sjöström ◽  
U Karlsson ◽  
E Cedergren
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Electron Micrographs ◽  
Periodic Acid ◽  
Frog Muscle ◽  
Nerve Terminals ◽  
Lead Citrate ◽  
Serial Sections ◽  
Transmission Electron ◽  
Reticular Zone

Glycogen in nerve terminals from the reticular zone of frog muscle was identified by transmission electron microscopy of both periodic acid-thiosemicarbazide-silverproteinate treated and UAc-PbCi-stained serial sections. A variable appearance of glycogen in the uranylacetate-lead citrate-stained nerve terminals was seen and is related to the preparative procedure. The study indicates the necessity of cytochemical identification for the assessment of glycogen organization in cells.

scholarly journals Method for Combined Observation of Serial Sections of Stented Arteries Embedded in Resin by Light Microscopy and Transmission Electron Microscopy

2018 ◽  
Vol 47 (3) ◽  
pp. 401-407 ◽  
Author(s):  
Atsushi Isobe ◽  
Kouichi Iwatani ◽  
Junko Souba ◽  
Hisako Terao ◽  
Hitomi Hagiwara ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Light Microscopy ◽  
Periodic Acid ◽  
Cell Junctions ◽  
Mixed Solution ◽  
Serial Sections ◽  
Thin Sections ◽  
Transmission Electron ◽  
Ultrathin Sections

We have developed a new method for obtaining information on whole tissues by light microscopy (LM) and ultrastructural features by transmission electron microscopy (TEM). This method uses serial sections of a stented artery embedded in resin. Stents were implanted in porcine coronary arteries in this study. The heart was perfusion fixed in a 2% paraformaldehyde and 1.25% glutaraldehyde mixed solution. The stented artery was then removed, fixed in 1% osmium, embedded in Quetol 651 resin, and sectioned serially. For LM, the black color of osmium was removed from the section by immersion in periodic acid and hydrogen peroxide after deplasticization. These sections were stained with hematoxylin and eosin and Elastica–Masson trichrome stain. For TEM, thin sections were re-embedded in Quetol 812 resin by the resupinate method and cut into ultrathin sections. A clear, fine structure was obtained, and organelles, microvilli, and cell junctions in the endothelium were easily observed. The combined observation of adjacent specimens by LM and TEM enabled us to relate histopathological changes in the millimeter scale to those in the nanometer scale.

Systemic Mastocytosis in a Goat

1995 ◽  
Vol 32 (6) ◽  
pp. 719-721 ◽  
Author(s):  
K. N. M. Khan ◽  
J. E. Sagartz ◽  
G. Koenig ◽  
K. Tanaka
Keyword(s):  
Electron Microscopy ◽  
Bone Marrow ◽  
Transmission Electron Microscopy ◽  
Mast Cells ◽  
Systemic Mastocytosis ◽  
Periodic Acid ◽  
Hypochromic Anemia ◽  
Postmortem Examination ◽  
Periodic Acid Schiff ◽  
Transmission Electron

Systemic mastocytosis was diagnosed in a 4-year-old, female Nubian goat. Clinically, the animal was depressed and had severe macrocytic hypochromic anemia and leukopenia. Postmortem examination revealed neoplastic mast cells invading the heart, lung, liver, spleen, lymph nodes, and bone marrow. Eosinophils were frequently admixed with infiltrating mast cells in all organs. Using routine light microscopy, histochemistry, and transmission electron microscopy, metachromatic and periodic acid—Schiff–positive granules were identified within the cytoplasm of neoplastic mast cells. Erythrophagocytosis was observed in some neoplastic cells, although its contribution to the anemia was not clear. This report represents the first description of mast cell neoplasia in the goat.

scholarly journals A modified periodic acid-thiocarbohydrazide-silver proteinate staining sequence for enhanced contrast and resolution of glycogen depositions by transmission electron microscopy.

1987 ◽  
Vol 35 (3) ◽  
pp. 393-399 ◽  
Author(s):  
H K Lo ◽  
T I Malinin ◽  
G I Malinin
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Acetic Acid ◽  
Periodic Acid ◽  
Transmission Electron ◽  
Proposed Modification ◽  
Subsequent Staining

Oxidation of araldite-embedded liver sections by 1% w/v aqueous H5IO6 for 15 min and a 5-min reaction of carbonyls with 1% w/v thiocarbohydrazide in 10% v/v acetic acid was employed for subsequent staining of glycogen with silver-proteinate (S-P). The network of branching intracellular glycogen aggregates was revealed by 15-min staining with S-P, whereas 24 hr incubation in S-P was necessary to enhance the contrast of glycogen inclusions. We conclude that the proposed modification of glycogen staining readily affords the means for its localization at a desired level of contrast and resolution.

scholarly journals The Depolarization-Evoked, Ca2+-Dependent Release of Exosomes From Mouse Cortical Nerve Endings: New Insights Into Synaptic Transmission

2021 ◽  
Vol 12 ◽  
Author(s):  
Guendalina Olivero ◽  
Francesca Cisani ◽  
Danilo Marimpietri ◽  
Daniela Di Paolo ◽  
Maria Cristina Gagliani ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Flow Cytometry ◽  
Light Scattering ◽  
Biochemical Analysis ◽  
Nerve Terminals ◽  
Transmission Electron ◽  
Presynaptic Release ◽  
Presynaptic Nerve Terminals ◽  
Active Release

Whether exosomes can be actively released from presynaptic nerve terminals is a matter of debate. To address the point, mouse cortical synaptosomes were incubated under basal and depolarizing (25 mM KCl-enriched medium) conditions, and extracellular vesicles were isolated from the synaptosomal supernatants to be characterized by dynamic light scattering, transmission electron microscopy, Western blot, and flow cytometry analyses. The structural and biochemical analysis unveiled that supernatants contain vesicles that have the size and the shape of exosomes, which were immunopositive for the exosomal markers TSG101, flotillin-1, CD63, and CD9. The marker content increased upon the exposure of nerve terminals to the high-KCl stimulus, consistent with an active release of the exosomes from the depolarized synaptosomes. High KCl-induced depolarization elicits the Ca2+-dependent exocytosis of glutamate. Interestingly, the depolarization-evoked release of exosomes from cortical synaptosomes also occurred in a Ca2+-dependent fashion, since the TSG101, CD63, and CD9 contents in the exosomal fraction isolated from supernatants of depolarized synaptosomes were significantly reduced when omitting external Ca2+ ions. Differently, (±)-baclofen (10 µM), which significantly reduced the glutamate exocytosis, did not affect the amount of exosomal markers, suggesting that the GABAB-mediated mechanism does not control the exosome release. Our findings suggest that the exposure of synaptosomes to a depolarizing stimulus elicits a presynaptic release of exosomes that occurs in a Ca2+-dependent fashion. The insensitivity to the presynaptic GABAB receptors, however, leaves open the question on whether the release of exosomes could be a druggable target for new therapeutic intervention for the cure of synaptopathies.

Scanning and Transmission Electron Microscopy of Human Lung in a Patient with Sarcoid-like Reaction

1974 ◽  
Vol 32 ◽  
pp. 14-15
Author(s):  
John H. L. Watson ◽  
Jessica Goodwin ◽  
E. Osborne Coates
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Hypersensitivity Reaction ◽  
Light Microscopy ◽  
Critical Point ◽  
Clinical Evidence ◽  
Human Lung ◽  
Uranyl Acetate ◽  
Lead Citrate ◽  
Transmission Electron

Biopsies of lung were taken at operation from a patient with semi-acute diffuse pulmonary infiltrates for study by TEM and SEM. Tissue by light microscopy showed non-caseating granulomas consistent with sarcoidosis. Clinical evidence suggested a hypersensitivity reaction related to inhalation of substance of undetermined nature. Samples were fixed in glutaraldehyde, cacodylate-buffered. They were critical point dried and coated with Au-Pd for SEM, and were handled appropriately for TEM in Araldite. Sections were contrasted with uranyl acetate and lead citrate.

scholarly journals Same Serial Section Correlative Light and Energy-filtered Transmission Electron Microscopy

2003 ◽  
Vol 51 (5) ◽  
pp. 605-612 ◽  
Author(s):  
Ying Ren ◽  
Michael J. Kruhlak ◽  
David P. Bazett-Jones
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Light Microscope ◽  
High Rate ◽  
Specific Cell ◽  
3D Analysis ◽  
Serial Sections ◽  
Correlative Imaging ◽  
Transmission Electron ◽  
Rate Of Success

Correlative imaging of a specific cell with both the light microscope and the electron microscope has proved to be a difficult task, requiring enormous amounts of patience and technical skill. We describe a technique with a high rate of success, which can be used to identify a particular cell in the light microscope and then to embed and thin-section it for electron microscopy. The technique also includes a method to obtain many uninterrupted, thin serial sections for imaging by conventional or energy-filtered transmission electron microscopy, to obtain images for 3D analysis of detail at the suborganelle level.

EM Study of Isopod Hemocytes

1998 ◽  
Vol 4 (S2) ◽  
pp. 1138-1139
Author(s):  
G. M. Vernon ◽  
E. J. Rappa ◽  
W. C. Murray ◽  
R. Witkus
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Morphological Analysis ◽  
Standard Technique ◽  
Uranyl Acetate ◽  
Lead Citrate ◽  
Small Granule ◽  
Thin Sections ◽  
Cytoplasmic Granules ◽  
Transmission Electron

Crustacean hemocytes have been characterized on the basis of cell size and nature of cytoplasmic granules. Based on light microscopic morphological analysis and cytochemistry, investigators variously named the hemocyte types (agranular, small-granule, large granule, undifferentiated, hyaline cells, non-explosive, explosive granulocytes, etc.). In his study of the isopod Armadillidium vulgare Faso adopted the terminology of Benjamin and James and referred to the hemocytes as hyaline cells, semi-granulocytes and granulocytes.In the present investigation we have studied the hemocytes of two isopods, Oniscus asellus and Armadillidium nasatum, using transmission electron microscopy. Hemolymph was collected by penetrating the posterior dorsal exoskeleton of 20 animals of each genus with a microcapillary pipette and drawing 3-5μL per isopod. The samples were processed following a standard technique. Thin sections were collected on 300 mesh copper grids, counterstained with 2% aqueous uranyl acetate and lead citrate, and viewed with a JEOL 1010 electron microscope.

Fine structure of Classopollis exines

1986 ◽  
Vol 64 (12) ◽  
pp. 3059-3074 ◽  
Author(s):  
John R. Rowley ◽  
Satish K. Srivastava
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Fine Structure ◽  
Upper Jurassic ◽  
Thin Sheets ◽  
Serial Sections ◽  
Thin Sections ◽  
Band Area ◽  
Transmission Electron ◽  
Oxidative Etching

Serial sections for light microscopy or transmission electron microscopy of two Classopollis pollen tetrads show that the exine structure, except for the nexine, has radially arranged rodlike units interwoven with transverse subunits. The nexine consists of strands or thin sheets except in the equatorial infratectal striate band area, where it is up to ca. 1 μm thick. Nexine is absent in the areas of the distal cryptopore and the subequatorial circumpolar infratectal canal. It is very thin or absent in the tetrad scar. Native contrast and reactivity to stain disappeared on immersion of thin sections in 1 M NaOH or HCl or in water. Reactivity to stains was regained after oxidizing the sections in KMnO4. Reactivity to stains appears to be dependent upon non-sporopollenin molecules embedded within exines. The above immersions remove stain reactive sites. Oxidative etching of sporopollenin exposes new sites. The specimens of Classopollis classoides Pflug studied and illustrated were picked from an Upper Jurassic sample (CRC 31519-2) collected at Osmington Mills locality, Dorset, England.

Centromere structure and chromosome number in mitosis of the colourless phytoflagellate Polytoma papillatum (Chlorophyceae, Volvocales, Chlamydomonadaceae)

Genome ◽  
1995 ◽  
Vol 38 (6) ◽  
pp. 1249-1254 ◽  
Author(s):  
Klaus Werner Wolf
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Chromosome Number ◽  
Higher Plants ◽  
Attachment Site ◽  
Dense Layer ◽  
Mitotic Metaphase ◽  
Serial Sections ◽  
Transmission Electron ◽  
Alternative Approach

Centromere structure is described in mitosis of the unicellular biflagellate alga Polytoma papillatum using transmission electron microscopy. The kinetochores are five-layered elements at the poleward surface of the chromosomes. The five layers consist of three dense plates interspersed by two transparent zones. The polemost dense layer serves as the attachment site for kinetochore microtubules and the innermost dense layer is intimately associated with the chromatin. The five-layered organization of the kinetochore in the alga is unusual. In animals, three-layered kinetochores are the rule. This type has also been found in some algae, while higher plants do not possess striated kinetochores. An attempt was made to determine the chromosome number of P. papillatum. Individual chromosomes could not be recognized with confidence, since there were numerous lateral contacts between the chromosomes throughout mitosis. An alternative approach, however, was successful. Counting the kinetochores in serial sections through mitotic metaphase and anaphase plates revealed a number of 15 chromosomes.Key words: anaphase, kinetochore, metaphase, microtubule.

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