Temporal and spatial interrelationships of confronting cisternae to nuclear envelope

1992 ◽  
Vol 50 (1) ◽  
pp. 930-931
Author(s):  
John R. Palisano
Keyword(s):  
Endoplasmic Reticulum ◽  
Nuclear Envelope ◽  
Tumor Cells ◽  
Hela Cells ◽  
Microscopic Investigation ◽  
Electron Microscopic Investigation ◽  
Serial Sections ◽  
Electron Microscopic ◽  
Fetal Rat ◽  
Temporal And Spatial

Although confronting cistemae (CC) have been observed in a variety of tumor cells and normal fetal rat, mouse, and human epithelial tissues, little is known about their origin or role in mitotic cells. While several investigators have suggested that CC arise from nuclear envelope (NE) folding back on itself during prophase, others have suggested that CC arise when fragments of NE pair with endoplasmic reticulum. An electron microscopic investigation of 0.25 um thick serial sections was undertaken to examine the origin of CC in HeLa cells.

Membrane biogenesis on isolated protoplasma surface

1978 ◽  
Vol 36 (2) ◽  
pp. 414-415
Author(s):  
R. K. Salyaev ◽  
V. I. Chernyshov ◽  
V. Ya. Kuzevanov
Keyword(s):  
Endoplasmic Reticulum ◽  
Epoxy Resins ◽  
Turgor Pressure ◽  
Microscopic Investigation ◽  
Electron Microscopic Investigation ◽  
Membrane Biogenesis ◽  
Electron Microscopic ◽  
Bivalent Cations ◽  
Pressure Compensation ◽  
Made In

A number of papers show the formation of a new membrane on the surface of protoplasm run out after cutting of Characeae alga cells in a medium containing bivalent cations.The drops of isolated protoplasm were prepared by cutting of Nitella cells in a special decompression chamber under the conditions of turgor pressure compensation. The drops were transferred into agar microcapsules (Fig. 1), the preparation of which was described in detail earlier (Salyaev, 1968). The walls of agar microcapsule were transparrent therefore protoplasm drops were clearly observed in a light microscope (Fig. II). All other operations such as fixation, dehydratation and embedding in epoxy resins were made in agar microcapsule.Electron microscopic investigation revealed that the method of a drop preparation preserved all components of a protoplasmic ultrastructure: endoplasmic reticulum, ribosomes, mitochondria etc., the hyaloplasm being rather hydrated (Fig. III). The surface of isolated protoplasmic drop was shown to be a typical membrane 80-90Åthick (Fig. IV).

scholarly journals Immunocytochemical localization of casein kinase II during interphase and mitosis.

1991 ◽  
Vol 114 (6) ◽  
pp. 1217-1232 ◽  
Author(s):  
I J Yu ◽  
D L Spector ◽  
Y S Bae ◽  
D R Marshak
Keyword(s):  
Hela Cells ◽  
Casein Kinase Ii ◽  
Microscopic Investigation ◽  
Electron Microscopic Investigation ◽  
Casein Kinase ◽  
Alpha Subunit ◽  
Electron Microscopic ◽  
Peptide Antigens ◽  
Hydroxyurea Treatment ◽  
The Individual

We have developed specific antibodies to synthetic peptide antigens that react with the individual subunits of casein kinase II (CKII). Using these antibodies, we studied the localization of CKII in asynchronous HeLa cells by immunofluorescence and immunoelectron microscopy. Further studies were done on HeLa cells arrested at the G1/S transition by hydroxyurea treatment. Our results indicate that the CKII alpha and beta subunits are localized in the cytoplasm during interphase and are distributed throughout the cell during mitosis. Further electron microscopic investigation revealed that CKII alpha subunit is associated with spindle fibers during metaphase and anaphase. In contrast, the CKII alpha' subunit is localized in the nucleus during G1 and in the cytoplasm during S. Taken together, our results suggest that CKII may play significant roles in cell division control by shifting its localization between the cytoplasm and nucleus.

Observations on healing tissue: A combined light and electron microscopic investigation

1963 ◽  
Vol 246 (733) ◽  
pp. 305-325 ◽  
Keyword(s):  
Endoplasmic Reticulum ◽  
Fine Structure ◽  
Light Microscopy ◽  
Secretory Activity ◽  
Microscopic Investigation ◽  
Electron Microscopic Investigation ◽  
Foreign Body Giant Cell ◽  
Electron Microscopic ◽  
Adventitial Cells

1. The process of healing in the rabbit ear chamber has been investigated in detail by correlating light microscopy, mainly in vivo , and electron microscopy. 2. During healing new vessels are formed from existing vessels by a process of sprouting and anastomosis, with subsequent remodelling of the loops so formed. 3. The fundamental process in the formation of vessels by sprouting is the mitotic division of existing endothelium, during which it retains its characteristic properties. 4. Blood vessel sprouts are composed of strands of tightly apposed cells formed in continuity with the walls of existing vessels. The subsequent canalization of such strands takes place extra-cellularly by a series of events largely as described by Billroth (1856). 5. The endothelium of recently formed vessels has a fine structure which distinguishes it clearly from that of more mature vessels. Certain features of this structure are compatible with a secretory activity by the endothelium during the formation of new vessels. 6. Evidence was obtained that in the course of differentiation of recently formed vessels fibroblast-like cells are incorporated into vessel walls to become adventitial cells, and that adventitial cells may undergo conversion to vascular smooth muscle cells. 7. Lymphatic endothelium exhibits properties during regeneration that confirm the specificity of this form of endothelium. 8. Cells with the characteristic fine structure of fibroblasts were frequently found in mitosis. The fibroblasts in the regions of active fibrogenesis had a highly developed cisternal form of endoplasmic reticulum. Vesicles and corresponding caveolae identifiable in such fibroblasts may provide a communication between the endoplasmic reticulum and the sites of fibrogenesis at the external surfaces of the cells. 9. Cells sharing characteristic features of fine structure formed a series which grouped together the monocyte, macrophage and foreign body giant cell. 10. Highly fibrillary intracytoplasmic tracts were found in both fibroblasts and macrophages. These tracts were equated with the fibroglial fibres of light microscopy. 11. ‘ Clear spaces ’ in advance of the growing fringe of blood vessels were temporary structures lined by a pavement of mesothelium-like cells. 12. No evidence was found of the formation of primitive mesenchymal tissue during healing in the mammal.

Fine-Structural Studies on Spontaneous and Induced Fusion of Higher Plant Protoplasts

1972 ◽  
Vol 11 (1) ◽  
pp. 59-75
Author(s):  
LYNDSEY A. WITHERS ◽  
E. C. COCKING
Keyword(s):  
Endoplasmic Reticulum ◽  
Membrane Fusion ◽  
Animal Cell ◽  
Microscopic Investigation ◽  
Electron Microscopic Investigation ◽  
Plant Tissues ◽  
Cell Wall Degrading Enzymes ◽  
Higher Plant ◽  
Electron Microscopic ◽  
Root Tissues

During the treatment of some plant tissues with cell-wall-degrading enzymes adjacent cells within the tissue fuse forming large multinucleate protoplasts. These have been termed spontaneous fusion bodies. The symplastic nature of plant tissues suggests that the retention of plasmodesmatal connexions might facilitate such spontaneous fusion. An electron-microscopic investigation of spontaneous fusion in tobacco-leaf and oat-root tissues has confirmed this suggestion. Enzymic degradation of the walls removes constrictions on the plasmodesmata, permitting their expansion, and as a result mixing of the cytoplasms of the fusing protoplasts can then occur. The fine structure of plasmodesmata and their relationship to the endoplasmic reticulum can be more easily studied in plasmodesmata which are undergoing expansion. It has been observed that the tubule which passes through the plasmodesma is in continuity with the endoplasmic reticulum membranes at either end. Models for plasmodesmatal structure are discussed in the light of this observation. The induced fusion of freely isolated protoplasts by sodium salts has been previously studied using the light microscope. Since it is difficult to follow the detailed mechanisms involved in the process, electron-microscopic methods have been employed in the present investigation. It appears that sodium nitrate first induces protoplast adhesion. This occasionally involves protrusions from the plasmalemma, not unlike microvilli. Following adhesion membrane fusion occurs, initially in localized regions, and then more generally. Eventually vacuolar fusion occurs facilitating complete cytoplasmic mixing. These findings are compared with events occurring during animal cell fusion and are discussed in relationship to a recent theoretical model for membrane fusion.

Experimental elimination of confronting cisternae in HeLa cells

1991 ◽  
Vol 49 ◽  
pp. 244-245
Author(s):  
J. R. Palisano
Keyword(s):  
Hela Cell ◽  
Nuclear Envelope ◽  
Tumor Cells ◽  
Hela Cells ◽  
Rapid Progress ◽  
Cell Synchronization ◽  
Epithelial Tissues ◽  
Fetal Rat ◽  
Mitotic Cells

Although confronting cisternae (CC) were described in 1955, very little is known about their origin or function. CC have been observed in a variety of tumor cells and normal fetal rat, mouse, and human epithelial tissues. While some evidence suggests that CC arise from the nuclear envelope (NE) folding back on itself during prophase, the question remains why are CC not seen in all mitotic cells or in all tumor cells instead of selected tumor cells. These seemingly inconsistent observations have led investigators to suggest that the occurrence of CC is a phenomenon resulting from the cells rapid progress through mitosis. This hypothesis was tested during HeLa cell synchronization studies which enabled the investigator to control the movement of the cells through mitosis.

Use of Uranium-Labeled Antibodies for Electron Microscopic Localization of Various Antigens in Mammalian Cells

1967 ◽  
Vol 25 ◽  
pp. 136-137
Author(s):  
J. P. Petrali ◽  
E. J. Donati ◽  
L. A. Sternberger
Keyword(s):  
Endoplasmic Reticulum ◽  
Hela Cells ◽  
Mammalian Cells ◽  
Specific Antiserum ◽  
Electron Microscopic ◽  
E Coli ◽  
Cytoplasmic Membranes ◽  
Viral Progeny ◽  
Ultrathin Sections ◽  
Electron Microscopic Localization

Specific contrast is conferred to subcellular antigen by applying purified antibodies, exhaustively labeled with uranium under immunospecific protection, to ultrathin sections. Use of Seligman’s principle of bridging osmium to metal via thiocarbohydrazide (TCH) intensifies specific contrast. Ultrathin sections of osmium-fixed materials were stained on the grid by application of 1) thiosemicarbazide (TSC), 2) unlabeled specific antiserum, 3) uranium-labeled anti-antibody and 4) TCH followed by reosmication. Antigens to be localized consisted of vaccinia antigen in infected HeLa cells, lysozyme in monocytes of patients with monocytic or monomyelocytic leukemia, and fibrinogen in the platelets of these leukemic patients. Control sections were stained with non-specific antiserum (E. coli).In the vaccinia-HeLa system, antigen was localized from 1 to 3 hours following infection, and was confined to degrading virus, the inner walls of numerous organelles, and other structures in cytoplasmic foci. Surrounding architecture and cellular mitochondria were unstained. 8 to 14 hours after infection, antigen was localized on the outer walls of the viral progeny, on cytoplasmic membranes, and free in the cytoplasm. Staining of endoplasmic reticulum was intense and focal early, and weak and diffuse late in infection.

Light and electron microscopic investigation of adenohypophyses of germfree, food-restricted, and germfree-food restricted aging, male lobund-wistar rats

1988 ◽  
Vol 46 ◽  
pp. 352-353
Author(s):  
G. Ilse ◽  
K. Kovacs ◽  
N. Ryan ◽  
T. Sano ◽  
L. Stefaneanu ◽  
...  
Keyword(s):  
Wistar Rats ◽  
Microscopic Investigation ◽  
Electron Microscopic Investigation ◽  
Aging Male ◽  
Sprague Dawley ◽  
Electron Microscopic ◽  
Sprague Dawley Rats ◽  
Old Rats ◽  
Ad Libitum ◽  
Microscopic Findings

Germfree state and food restriction have been shown to increase life span and delay tumor occurrence in rats. We report here the histologic, immunocytochemical and electron microscopic findings of adenohypophyses of aging, male Lobund-Wistar rats raised at Lobund Laboratories. In our previous study, the morphologic changes in the adenohypophyses of old rats have been extensively investigated by histology, immunocytochemistry and electron microscopy. Lactotroph adenomas were frequent in Long-Evans and Sprague-Dawley rats, whereas gonadotroph adenomas were frequent in Sprague-Dawley and Wistar rats.Male Lobund-Wistar rats were divided into four groups: 1) conventional, which were raised under normal non-germfree environment and received food ad libitum; 2) germfree-food ad libitum; 3) conventional environment-food restricted and 4) germfree-food restricted. The adenohypophyses were removed from 6-month-, 18-month- and 30-month-old rats. For light microscopy, adenohypophyses were fixed in formalin and embedded in paraffin.

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.

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 Microscopic investigation of crooke’s change in the pituitaries of patients with hypercorticism

1989 ◽  
Vol 47 ◽  
pp. 848-849
Author(s):  
E. Horvath ◽  
K. Kovacs ◽  
L. Stefaneanu ◽  
N. Losinski
Keyword(s):  
Nucleolar Organizer ◽  
Microscopic Investigation ◽  
Electron Microscopic Investigation ◽  
Ectopic Acth Syndrome ◽  
Nucleolar Organizer Regions ◽  
Electron Microscopic ◽  
Human Pituitary ◽  
Ectopic Acth ◽  
Crooke’S Hyalinization

Human pituitary corticotropins have unique morphologic markers: bundles of type-1 filaments, measuring approximately 70 A in width and representing cytokeratin. The extreme ring-like accumulation of type-1 filaments, known as Crooke's hyalinization, signals functional suppression of the corticotropins and occurs in endogenous and exogenous glucocorticoid excess, caused by ACTH-secreting pituitary adenoma, glucocorticoid secreting adrenocortical tumor, ectopic ACTH-syndrome and administration of pharmacologic doses of glucocorticoids. Cells of autonomous corticotroph adenomas usually do not show Crooke's hyalin change. A minority of these tumors, however, retains sensitivity to the negative feed-back effect of elevated blood glucocorticoid levels and display typical Crooke’s change.In the present study pituitary corticotropins in various phases of Crooke's hyalinization were investigated in patients with glucocorticoid excess of various origin, applying histology, immunocytochemistry, count of argyrophilic nucleolar organizer regions (AgNOR), and transmission electron microscopy.

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