Effects of Glyphosate on Chloroplast Ultrastructure of Quackgrass Mesophyll Cells

Weed Science ◽  
1976 ◽  
Vol 24 (1) ◽  
pp. 22-25 ◽  
Author(s):  
W. F. Campbell ◽  
J. O. Evans ◽  
S. C. Reed
Keyword(s):  
Electron Microscopy ◽  
Endoplasmic Reticulum ◽  
Electron Microscope ◽  
Chloroplast Ultrastructure ◽  
Cellular Damage ◽  
Chloroplast Envelope ◽  
Mesophyll Cells ◽  
Subsequent Formation ◽  
Complete Disruption ◽  
Standard Techniques

Phytotoxicity of glyphosate (N-(phosphonomethyl) glycine), applied at 0, 0.56, 1.12, 1.68, 2.24 and 4.49 kg ai/ha to uniform, naturally growing quackgrass, [Agropyron repens (L.) Beauv.] plants, was studied with the electron microscope. Visible damage (yellowing of the leaves) to the plants was observed at the 2.24 and 4.49 kg ai/ha dosage rates within 72 hr. Similar damage became evident 120 hr after treatment at the 0.56 to 1.68 dosages. Leaf discs (1 mm in diameter) were harvested at 24, 48, 96, and 192 hr and prepared for electron microscopy by standard techniques. Cellular damage could be detected at all dosage rates as early as 24 hr after treatment. The type of damage observed was partial to complete disruption of the chloroplast envelope, and swelling of the rough endoplasmic reticulum (RER) with a subsequent formation of vesicles. With loss of integrity of the envelope, the chloroplast became completely disrupted with increased time. Other organelles within the cell were also destroyed.

Copper Localization in Cirrhotic Rat Liver by Scanning Electron Microscopy

1969 ◽  
Vol 27 ◽  
pp. 38-39 ◽  
Author(s):  
J. C. Russ ◽  
E. McNatt
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Endoplasmic Reticulum ◽  
Electron Microscope ◽  
Copper Acetate ◽  
Lead Citrate ◽  
Dense Bodies ◽  
Transmission Electron ◽  
Electron Mode ◽  
Scanning Electron

In order to study the retention of copper in cirrhotic liver, rats were made cirrhotic by carbon tetrachloride inhalation twice weekly for three months and fed 0.2% copper acetate ad libidum in drinking water for one month. The liver tissue was fixed in osmium, sectioned approximately 2000 Å thick, and stained with lead citrate. The section was examined in a scanning electron microscope (JEOLCO JSM-2) in the transmission electron mode.Figure 1 shows a typical area that includes a red blood cell in a sinusoid, a disse, and a portion of the cytoplasm of a hepatocyte which contains several mitochondria, peribiliary dense bodies, glycogen granules, and endoplasmic reticulum.

scholarly journals ELECTRON MICROSCOPY OF CENTRIFUGED HYPHAE OF NEUROSPORA

1961 ◽  
Vol 9 (3) ◽  
pp. 609-617 ◽  
Author(s):  
M. Zalokar
Keyword(s):  
Electron Microscopy ◽  
Endoplasmic Reticulum ◽  
Electron Microscope ◽  
Optical Microscope ◽  
Granular Structure ◽  
Cell Physiology ◽  
Cell Structures ◽  
Light Area ◽  
Fat Bodies

Normal and centrifuged hyphae of Neurospora were studied with the electron microscope. The following cell structures could be identified: nuclei with nucleoli, mitochondria, endoplasmic reticulum, ribosomes, glycogen, fat bodies, vacuoles, and vesicles with an inner canalicular system, of unknown nature. In centrifuged hyphae, the glycogen layer appeared as a light area, with a slight indication of granular structure. The ribosome layer consisted of densely packed ribosomes without any membranes. The mitochondrial layer contained spaces filled with ribosomes. The nuclei were loosely packed, with endoplasmic reticulum between them. The "enchylema" layer was composed of vesicles belonging to the endoplasmic reticulum. The vacuolar layer was poorly preserved and consisted of double-walled vesicles. Fat appeared as stellate osmiophilic droplets. These observations were compared with previous observations under the optical microscope and their meaning for cell physiology was discussed.

scholarly journals Laminin in cultured mouse C1300 neuroblastoma cells: immunocytochemical localization by pre- and postembedding electron microscope procedures.

1983 ◽  
Vol 31 (6) ◽  
pp. 755-764 ◽  
Author(s):  
P Liesi
Keyword(s):  
Electron Microscopy ◽  
Endoplasmic Reticulum ◽  
Electron Microscope ◽  
Plasma Membranes ◽  
Neuroblastoma Cells ◽  
Immunocytochemical Localization ◽  
Adhesion Protein ◽  
Antibody Method ◽  
Ultrathin Sections ◽  
Intercellular Connections

Laminin was localized in cultured mouse C1300 neuroblastoma cells by applying the peroxidase-antiperoxidase technique in preembedding electron microscopy. The results were compared to those obtained by indirect immunofluorescence and by the colloidal gold second antibody method on Epon-embedded ultrathin sections. Laminin was found in the cell membranes and within the rough endoplasmic reticulum as well as in intracytoplasmic vacuoles. Plasma membranes of the neuroblastoma cells showed a patchy localization of laminin that was apparently involved in cell-to-substrate attachment and in gap junction-like intercellular connections. Under normal conditions, the Golgi cisternae contained no laminin. Pretreatment of cells with micromolar concentrations of monensin, however, lead to an accumulation of laminin within the Golgi cisternae. These results support a role for laminin as an adhesion protein in cultured neuroblastoma cells and indicate that laminin is transported through the Golgi complex.

Cytological studies on physodes in the vegetative cells of Cystoseira stricta Sauvageau (Phaeophyta, Fucales)

1980 ◽  
Vol 41 (1) ◽  
pp. 209-231
Author(s):  
L. Pellegrini
Keyword(s):  
Electron Microscopy ◽  
Endoplasmic Reticulum ◽  
Cell Walls ◽  
Higher Plants ◽  
Close Association ◽  
Chloroplast Envelope ◽  
Osmiophilic Granules ◽  
Cytological Changes ◽  
Ultrastructural Characteristics ◽  
Secondary Lysosomes

Physodes have been recognized in meristodermic and promeristematic cells by correlated light- and electron-microscope investigations using different fixation procedures. They are vesicles which contain an osmiophilic material of phenolic nature. Their content changes in appearence according to the fixative used. Osmiophilic deposits are often associated with coiled and disturbed lamellar formations. It has been possible to distinguish several ultrastructural stages which occur during the secretion of the content of the physodes, namely: a chloroplast accumulation and exudation, and a reticular transport to accumulation vacuoles where materials undergo evolution or hydrolysis. Inside plastids, osmiophilic granules are found in close association with thylakoid stacks. They may contain the polyphenolic precursors of physodes, though this has not yet been proved by electron-microscopy procedures. They are expelled from plastids to the chloroplast endoplasmic reticulum. The mechanism of transfer through the chloroplast envelope endoplasmic reticulum. The mechanism of transfer through the chloroplast envelope remains to be elucidated. Lytic activities have been reported inside physodes which might thus act in the same way as the secondary lysosomes of animals and higher plants. Occasionally, the physode content seems to be excreted from the cytoplasm to the cell walls by exocytosis after the probable fusion of plasmalemma and tonoplast. These cytological changes, observed in the vegetative apex of a brown alga, recall some ultrastructural characteristics of the secretory processes described in various glandular tissues of higher plants and which consist of the synthesis, the transport and the elimination of an exudate of flavonic, terpenic or lipophenolic nature.

scholarly journals Electron Microscope Studies on Normal Human Myeloid Elements

Blood ◽  
1964 ◽  
Vol 23 (3) ◽  
pp. 300-320 ◽  
Author(s):  
ROBERT J. CAPONE ◽  
EVA LURIE WEINREB ◽  
GEORGE B. CHAPMAN
Keyword(s):  
Electron Microscopy ◽  
Endoplasmic Reticulum ◽  
Electron Microscope ◽  
Chromatin Condensation ◽  
Light And Electron Microscopy ◽  
Direct Connection ◽  
Granule Formation ◽  
Specific Granules ◽  
Normal Human

Abstract The development of representative myeloid elements is traced by correlated light and electron microscopy. Cytoplasmic changes during maturation of granulocytes from the myeloblast include loss of basophilia, development of the endoplasmic reticulum complex, decrease in number of mitochondria, and granule formation. The endoplasmic reticulum vesicles increase in size and number during the promyelocyte and myelocyte stages, accompanied by the appearance of non-specific and specific granules, and decrease again during the cytosomal maturation of the metamyelocyte. A reduction in number of mitochondria is noted through the metamyelocyte stage. The apparent continuity of the limiting membranes of both the granules and mitochondria with those of the cisternae of endoplasmic reticulum suggests a direct connection among cytosomal organelles. The role of the endoplasmic reticulum in granulogenesis is discussed. Maturation of the nucleus involves a loss of nucleolar differentiation by a loosening of the compact fibrillar aggregates, and progressive chromatin condensation.

scholarly journals AN ELECTRON MICROSCOPE STUDY OF THE ENDOPLASMIC RETICULUM IN NEWT NOTOCHORD CELLS AFTER DISTURBANCE WITH ULTRASONIC TREATMENT AND SUBSEQUENT REGENERATION

1964 ◽  
Vol 20 (1) ◽  
pp. 175-183 ◽  
Author(s):  
G. G. Selman ◽  
A. Jurand
Keyword(s):  
Electron Microscopy ◽  
Endoplasmic Reticulum ◽  
Electron Microscope ◽  
Light Microscopy ◽  
Ultrasonic Treatment ◽  
Electron Microscope Study ◽  
Triturus Alpestris ◽  
Notochord Cells ◽  
Parallel Arrays ◽  
Subsequent Regeneration

Ultrasonic treatment of the tails of Triturus alpestris tadpoles, at intensities of 8 to 15 watts/cm2, at 1 megacycle/sec., for 5 minutes, disrupted the epidermis and caused pycnosis in individual cells of the muscle and neural tube, but caused no damage to the notochord that could be detected by light microscopy. Electron microscopy showed that this ultrasonic treatment disordered nearly all the endoplasmic reticulum (ER) of the notochord cells into irregularly rounded vesicles, but within 3 hours after treatment some parallel arrays of normal endoplasmic reticulum were seen near, and continuous with, the outer nuclear membrane. In addition, a re-ordering of the previously disordered ER took place throughout the cytoplasm, in some cases. A classification was made of the state of the ER as shown in electron micrographs of material fixed immediately, 3, and 24 hours after treatment. This showed that more than half the total endoplasmic reticulum in notochord cells was normal again by 24 hours after treatment.

scholarly journals Electron microscope localization of acetylcholinesterase and butyrylcholinesterase in the ciliary ganglion of the cat.

1984 ◽  
Vol 32 (8) ◽  
pp. 849-861 ◽  
Author(s):  
R Davis ◽  
G B Koelle ◽  
U J Sanville
Keyword(s):  
Electron Microscopy ◽  
Endoplasmic Reticulum ◽  
Electron Microscope ◽  
Superior Cervical Ganglion ◽  
Extracellular Space ◽  
Plasma Membranes ◽  
Ganglion Cells ◽  
Ciliary Ganglion ◽  
Cervical Ganglion ◽  
High Concentrations

Ciliary ganglia (CG) of cats were stained for acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) by the bis-(thioacetoxy) aurate (I), or Au(TA)2, method for examination by electron microscopy. Acetylcholinesterase was localized along the axolemmas of the preganglionic fibers and their terminals and on the plasmalemmas of the perikarya and dendrites of the ganglion cells, as in the cat superior cervical ganglion (SCG). In contrast to the SCG, AChE was also found in significant amounts in the rough endoplasmic reticulum of the CG cells and dendrites, and in varying but high concentrations in channels of extracellular space in the complex capsular region surrounding the perikarya and dendrites. Butyrylcholinesterase was confined chiefly to the dendritic and perikaryonal plasma membranes of the ganglion cells, as in the SCG. Lysosomes and mitochondria were stained chiefly for non-cholinesterase enzymes, as indicated by the physostigmine-treated controls. The significance of these distributions is discussed.

FINE STRUCTURE IN DETACHED, SENESCING WHEAT LEAVES

1965 ◽  
Vol 43 (6) ◽  
pp. 747-755 ◽  
Author(s):  
Michael Shaw ◽  
M. S. Manocha
Keyword(s):  
Electron Microscopy ◽  
Endoplasmic Reticulum ◽  
Fine Structure ◽  
Osmium Tetroxide ◽  
Mesophyll Cells ◽  
Laboratory Bench ◽  
Detached Leaves ◽  
Petri Dishes ◽  
Wheat Leaves ◽  
Cytoplasmic Ribosomes

Detached leaves of Little Club wheat were allowed to senesce on water or on kinetin (10 mg/l.) in petri dishes on the laboratory bench. Samples taken at intervals of 24 to 48 hours for 8 to 10 days were fixed in permanganate or osmium tetroxide, embedded, usually in araldite or epon, and examined by electron microscopy. Abnormalities were noted in the endoplasmic reticulum (ER) of the mesophyll cells 2 days after the leaves were detached; ER and cytoplasmic ribosomes were not present after 4 or 5 days. Swelling of the mitochondria and degeneration of the cristae, collapse of the chloroplast grana, and abnormalities in nuclear structure were noted after 3 days. Vacuolar contraction occurred in some cells after 4 days but the plasma membrane usually remained unbroken until the seventh or eighth day, by which time the mitochondria were no longer recognizable and most of the chloroplasts and nuclei had also disintegrated.Kinetin induced an increase in the amount of ER and ribosomes and markedly delayed the degeneration of cellular fine structure.

Electron Microscopy Observations on a Spontaneous Mastocytoma in a Dog

1964 ◽  
Vol 50 (5) ◽  
pp. 375-402 ◽  
Author(s):  
Natale Pennelli ◽  
Luigi Mazzarella ◽  
Wim Misdorp
Keyword(s):  
Electron Microscopy ◽  
Endoplasmic Reticulum ◽  
Plasma Membrane ◽  
Electron Microscope ◽  
Methyl Methacrylate ◽  
Toluidine Blue ◽  
Golgi Region ◽  
Specific Granules ◽  
Different Types ◽  
Ultrastructural Characteristics

The ultrastructure of a dog mastocytoma examined with the electron microscope after fixation in glutaraldehyde, post-fixation in osmiumtetroxide and butyl-methyl methacrylate embedding is described. The ultrastructural characteristics with particular regard to the submicroscopic morphology of specific granules were studied in details, also with the aid of comparative observations on thick sections stained by Giemsa and toluidine blue. On the basis of their observations, the authors describe the following characteristics of neoplastic mastcells: microvilli, a well-developed Golgi region, centrioles, mithocondria, ribosomes, endoplasmic reticulum and 4 different types of granules. Other mastcells, with various degree of regressive phoenomena, had almost no microvilli, multiple interruptions of plasma membrane, mithocondrial swelling as well as vacuolar and fibrillar aspect of the cytoplasm. The morphology of different types of intracytoplasmic granules is discussed also in the light of parallel observations made by other authors. Expulsions of granules were not observed. The hypothesis of the phospholipidic nature of the lamellar component of granules is suggested.

ELECTRON MICROSCOPY OF ISOLATED PLANT MITOCHONDRIA AND PLASTIDS USING BOTH THE THIN-SECTION AND NEGATIVE-STAINING TECHNIQUES

1965 ◽  
Vol 43 (6) ◽  
pp. 647-655 ◽  
Author(s):  
D. F. Parsons ◽  
W. D. Bonner Jr. ◽  
J. G. Verboon
Keyword(s):  
Electron Microscopy ◽  
Endoplasmic Reticulum ◽  
Electron Microscope ◽  
Thin Section ◽  
Insect Cell ◽  
Preliminary Report ◽  
Animal Cell ◽  
Plant Mitochondria ◽  
Negative Staining ◽  
Staining Techniques

Six types of plant mitochondria have been isolated by improved techniques and examined with the electron microscope by the thin-section and negative-staining techniques. In general, the mitochondria appeared well preserved. There was minimal contamination by endoplasmic reticulum but some plastids were present. The morphology of the plant mitochondria is compared with that of animal cell mitochondria. Negative staining showed that the inner membranes were covered with projecting knob-like subunits, as previously described for animal and insect cell mitochondria. The outer membrane showed a characteristic pitted appearance that was apparently due to 28 Å holes in the membrane. A preliminary report is also given of the appearance of negatively stained membranes of chloroplasts.

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