scholarly journals FINE STRUCTURE OF THE CILIARY EPITHELIUM OF THE RABBIT, WITH PARTICULAR REFERENCE TO "INFOLDED MEMBRANES," "VESICLES," AND THE EFFECTS OF DIAMOX

1963 ◽  
Vol 17 (3) ◽  
pp. 641-659 ◽  
Author(s):  
John Mcd. Tormey
Keyword(s):  
Osmium Tetroxide ◽  
Plasma Membranes ◽  
Structural Changes ◽  
Secretory Activity ◽  
Structural Features ◽  
Ciliary Epithelium ◽  
Albino Rabbit ◽  
Serial Sections ◽  
Experimental Conditions ◽  
Tubular Endoplasmic Reticulum

The structure of the ciliary epithelium of the adult albino rabbit has been studied by electron microscopy. Material was fixed in osmium tetroxide and embedded in epoxy resins. Two hitherto unappreciated features of the non-pigmented epithelial layer are described. First, the "infolded plasma membranes" described by previous workers are shown by serial sections to be projections or interdigitations from adjacent cells. Second, the "rows of vesicles" described by previous workers are shown by serial sections to be part of an unusual form of smooth-surfaced tubular endoplasmic reticulum. The tubules are highly convoluted and extensively interconnected. They are arranged in sheets, so that a cross-section through a sheet gives the appearance of a row of vesicles. The other structural features of the ciliary epithelium are also described. Previous workers have reported that Diamox, which inhibits the secretory activity of the epithelium, causes profound structural changes. An effort has been made to confirm these reports under carefully controlled experimental conditions. It was found that secretion could be inhibited by a maximally effective dose of Diamox without the occurrence of any detectable structural changes. The physiological significance of these findings is discussed.

scholarly journals ARTIFACTUAL LOCALIZATION OF FERRITIN IN THE CILIARY EPITHELIUM IN VITRO

1965 ◽  
Vol 25 (2) ◽  
pp. 1-7 ◽  
Author(s):  
John Mcd. Tormey
Keyword(s):  
Electron Microscopy ◽  
Plasma Membrane ◽  
Basement Membrane ◽  
Osmium Tetroxide ◽  
Colloidal Particles ◽  
Ciliary Epithelium ◽  
Albino Rabbit ◽  
Cytoplasmic Matrix ◽  
Tracer Particles

The accumulation of ferritin by the ciliary epithelium of the adult albino rabbit has been studied by electron microscopy. The experiments have been carried out under in vitro conditions, such that any uptake observed should be the result of passive diffusion of the tracerparticles rather than the product of active metabolic processes. The cells were fixed in osmium tetroxide and embedded in Araldite. Ferritin was found localized in three areas: in rows of apparent vesicles, free in the cytoplasmic matrix, and in the basement membrane. Some of the conclusions reached are as follows. The appearance of tracer in rows of vesicles is not in itself an adequate demonstration of pinocytosis. The permeability of the plasma membrane is drastically increased by osmium tetroxide fixation, so that tracer particles are free to diffuse across the membrane and wander through the cytoplasm. These results indicate the serious danger of being misled by artifacts when colloidal particles are used as tracers.

scholarly journals STRUCTURAL CHANGES PRODUCED IN BROWN-PEARCE CARCINOMA CELLS BY MEANS OF A SPECIFIC ANTIBODY AND COMPLEMENT

1953 ◽  
Vol 97 (1) ◽  
pp. 145-162 ◽  
Author(s):  
Bernard Kalfayan ◽  
John G. Kidd
Keyword(s):  
Phase Contrast ◽  
Plasma Membranes ◽  
Structural Changes ◽  
Complete Loss ◽  
Carcinoma Cells ◽  
Rabbit Serum ◽  
Phase Contrast Microscopy ◽  
Rapid Loss ◽  
Experimental Conditions ◽  
Contrast Microscopy

Structural changes were regularly observed in Brown-Pearce rabbit carcinoma cells that had been brought into contact, in the presence of complement, with rabbit serum containing an antibody that reacts specifically with a distinctive sedimentable constituent of the carcinoma cells. The cellular changes appeared rapidly and were accompanied by an equally rapid loss of viability. The structural changes, as disclosed by histological and cytological methods, including phase contrast microscopy, were described in detail and illustrated. Essentially they were characterized by the entrance of considerable quantities of fluid into the cell, together with swelling and disorganization of its cytoplasm, vesiculation and rupture of the bulk of its cytoplasmic particles, and rapid and virtually complete loss of cytoplasmic basophilism. The plasma membranes, though stretched thin about the swollen cytoplasm of the altered cells, and otherwise changed also, remained unruptured during many hours' observation. The nuclei of the altered cells, however, remained relatively un-changed, their membranes persisting unruptured and their sap remaining wholly transparent and undiminished in amount for long periods, while within it the chromatin retained its staining properties, though sometimes becoming clumped and marginated; by contrast, the nucleoli of the treated cells promptly shrank and lost much of their affinity for the basic dyes. The experimental conditions under which the structural changes became manifest were given in detail, together with an analysis of the findings and brief mention of certain of their implications for cytology and immunology.

scholarly journals FINE STRUCTURAL CHANGES IN THE FLAGELLUM OF THE SPERMATID IN EXPERIMENTAL CRYPTORCHIDISM OF THE RAT

1963 ◽  
Vol 18 (2) ◽  
pp. 337-344 ◽  
Author(s):  
Toshio Nagano
Keyword(s):  
Electron Microscope ◽  
Cross Sections ◽  
Osmium Tetroxide ◽  
Structural Changes ◽  
Abdominal Cavity ◽  
Main Axis ◽  
The Other ◽  
Experimental Conditions ◽  
Fibrous Sheath ◽  
Axial Filament

Rat testes were confined to the abdominal cavity by operation. After 1 to 26 days they were excised, fixed with osmium tetroxide, sectioned, and examined with the electron microscope. Changes in the axial filament complex of the spermatid flagellum appeared 2 days after operation, and the arrangement of filaments in the middle- and main pieces of some spermatid tails was disordered as compared to the 9 + 2 filament arrangement in the tails of the control spermatids and in other flagella and cilia. In cross-sections, the filaments in the experimental material were nine or less in number, and each of them was single and dense. Occasionally some were double, and in those instances one filament was dense and the other was light and tubular. The central filaments were obscure. In longitudinal sections,the filaments were not parallel to the main axis of the flagella or to each other. It was assumed that the central filaments were more sensitive to the experimental conditions than the peripheral pairs of filaments. Furthermore, the light filaments of the peripheral pairs were more sensitive than the dense filaments. Besides the axial filament complex, the fibrous sheath which surrounds it in the main piece was also changed. The plasma membrane of the changed flagella disappeared or became fragmented.

Application of stereological analysis of cell volume to isolated myocytes in culture with and without adrenergic innervation

1990 ◽  
Vol 48 (3) ◽  
pp. 416-417
Author(s):  
Jane K. Rosenthal ◽  
Dianne L. Atkins ◽  
William J. Marvin ◽  
Penny A. Krumm
Keyword(s):  
Cardiac Myocytes ◽  
Structural Changes ◽  
Three Dimensional ◽  
Adrenergic Innervation ◽  
Culture Cell ◽  
Serial Sections ◽  
Newborn Rats ◽  
Primary Culture Cell ◽  
Biological Studies ◽  
Cell Volumes

To comprehend structural changes in cardiac myocytes accompanying adrenergic innervation, it is essential that a three dimensional analysis be performed. To date, biological studies which utilize stereological methods have been limited to cells in tissue and in organs. Our laboratory has utilized current stereological techniques for measuring absolute volumes of individual myocytes in primary culture. Cell volumes are calculated for two distinct groups of cells at 96 hours in culture: isolated myocytes and myocytes innervated with adrenergic neurons (Figure 1).Cardiac myocytes are cultured from the ventricular apices of newborn rats. Cells are plated directly onto tissue culture dishes with or without preplated explants from the paravertebral thoracolumbar sympathetic chain. On day four cultures are photographed and marked for one-to-one cell location. Following conventional fixation and embeddment in eponate-12, the cells are relocated and mounted for microtomy. The cells are completely sectioned at 120nm in their parallel orientation to the surface of the dish (Figure 2). Serial sections are collected on formvar coated slotted grids and are recorded in sequence.

scholarly journals Unusual Structural Features in the Adduct of Dirhodium Tetraacetate with Lysozyme

2021 ◽  
Vol 22 (3) ◽  
pp. 1496
Author(s):  
Domenico Loreto ◽  
Giarita Ferraro ◽  
Antonello Merlino
Keyword(s):  
Anticancer Agents ◽  
Structural Features ◽  
Side Chain ◽  
Side Chains ◽  
Valuable Insight ◽  
Experimental Conditions ◽  
Egg White Lysozyme ◽  
Potential Applications ◽  
Model Protein ◽  
Hen Egg White

The structures of the adducts formed upon reaction of the cytotoxic paddlewheel dirhodium complex [Rh2(μ-O2CCH3)4] with the model protein hen egg white lysozyme (HEWL) under different experimental conditions are reported. Results indicate that [Rh2(μ-O2CCH3)4] extensively reacts with HEWL:it in part breaks down, at variance with what happens in reactions with other proteins. A Rh center coordinates the side chains of Arg14 and His15. Dimeric Rh–Rh units with Rh–Rh distances between 2.3 and 2.5 Å are bound to the side chains of Asp18, Asp101, Asn93, and Lys96, while a dirhodium unit with a Rh–Rh distance of 3.2–3.4 Å binds the C-terminal carboxylate and the side chain of Lys13 at the interface between two symmetry-related molecules. An additional monometallic fragment binds the side chain of Lys33. These data, which are supported by replicated structural determinations, shed light on the reactivity of dirhodium tetracarboxylates with proteins, providing useful information for the design of new Rh-containing biomaterials with an array of potential applications in the field of catalysis or of medicinal chemistry and valuable insight into the mechanism of action of these potential anticancer agents.

scholarly journals Interaction of Lactoferrin with Unsaturated Fatty Acids: In Vitro and In Vivo Study of Human Lactoferrin/Oleic Acid Complex Cytotoxicity

Materials ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1602
Author(s):  
Anna Elizarova ◽  
Alexey Sokolov ◽  
Valeria Kostevich ◽  
Ekaterina Kisseleva ◽  
Evgeny Zelenskiy ◽  
...  
Keyword(s):  
Oleic Acid ◽  
Structural Changes ◽  
Unsaturated Fatty Acids ◽  
Structural Features ◽  
Control Group ◽  
Acid Complex ◽  
Hepatoma 22A ◽  
Constitutive Parameters

As shown recently, oleic acid (OA) in complex with lactoferrin (LF) causes the death of cancer cells, but no mechanism(s) of that toxicity have been disclosed. In this study, constitutive parameters of the antitumor effect of LF/OA complex were explored. Complex LF/OA was prepared by titrating recombinant human LF with OA. Spectral analysis was used to assess possible structural changes of LF within its complex with OA. Structural features of apo-LF did not change within the complex LF:OA = 1:8, which was toxic for hepatoma 22a cells. Cytotoxicity of the complex LF:OA = 1:8 was tested in cultured hepatoma 22a cells and in fresh erythrocytes. Its anticancer activity was tested in mice carrying hepatoma 22a. In mice injected daily with LF-8OA, the same tumor grew significantly slower. In 20% of animals, the tumors completely resolved. LF alone was less efficient, i.e., the tumor growth index was 0.14 for LF-8OA and 0.63 for LF as compared with 1.0 in the control animals. The results of testing from 48 days after the tumor inoculation showed that the survival rate among LF-8OA-treated animals was 70%, contrary to 0% rate in the control group and among the LF-treated mice. Our data allow us to regard the complex of LF and OA as a promising tool for cancer treatment.

scholarly journals Post-operative rehabilitation and nutrition in osteoarthritis

F1000Research ◽  
2016 ◽  
Vol 3 ◽  
pp. 116 ◽  
Author(s):  
Giuseppe Musumeci ◽  
Ali Mobasheri ◽  
Francesca Maria Trovato ◽  
Marta Anna Szychlinska ◽  
Rosa Imbesi ◽  
...  
Keyword(s):  
Articular Cartilage ◽  
Physical Exercise ◽  
Structural Changes ◽  
Exercise Program ◽  
Structural Features ◽  
Synovial Joint ◽  
Comprehensive Overview ◽  
Postoperative Rehabilitation ◽  
Keywords Osteoarthritis ◽  
Rehabilitation Exercise

Osteoarthritis (OA) is a degenerative process involving the progressive loss of articular cartilage, synovial inflammation and structural changes in subchondral bone that lead to loss of synovial joint structural features and functionality of articular cartilage. OA represents one of the most common causes of physical disability in the world. Different OA treatments are usually considered in relation to the stage of the disease. In the early stages, it is possible to recommend physical activity programs that can maintain joint health and keep the patient mobile, as recommended by OA Research Society International (OARSI) and European League Against Rheumatism (EULAR). In the most severe and advanced cases of OA, surgical intervention is necessary. After, in early postoperative stages, it is essential to include a rehabilitation exercise program in order to restore the full function of the involved joint. Physical therapy is crucial for the success of any surgical procedure and can promote recovery of muscle strength, range of motion, coordinated walking, proprioception and mitigate joint pain. Furthermore, after discharge from the hospital, patients should continue the rehabilitation exercise program at home associated to an appropriate diet. In this review, we analyze manuscripts from the most recent literature and provide a balanced and comprehensive overview of the latest developments on the effect of physical exercise on postoperative rehabilitation in OA. The literature search was conducted using PubMed, Scopus, Web of Science and Google Scholar, using the keywords ‘osteoarthritis’, ‘rehabilitation’, ‘exercise’ and ‘nutrition’. The available data suggest that physical exercise is an effective, economical and accessible to everyone practice, and it is one of the most important components of postoperative rehabilitation for OA.

scholarly journals Century-Long Dynamics of the Land Use Structure in the United States

2020 ◽  
pp. 220-231
Author(s):  
Valerij Minat
Keyword(s):  
United States ◽  
Land Use ◽  
Structural Changes ◽  
The United States ◽  
Structural Features ◽  
Summary Table ◽  
Land Use Structure ◽  
Periodic Dynamics ◽  
Space Dynamics ◽  
American Society

The paper studies the experience of American land use in the twentieth century on the territory of 48 contiguous continental states. Changes in time and space (dynamics) of the main indicators of distribution and use of land resources that form the structural appearance of the U.S. land fund are shown. Based on the analysis of the countrys land use structure, the resulting part of which is a summary table, the periodic dynamics of the land use structure (in twenty-year time intervals) is considered, and the dependence of structural changes in land use on the level and nature of the socio-economic development of American society is shown. The study of the age-old dynamics of structural features of American land use conducted on the basis of scientific materials of American scientists and data from official American statistics makes it possible to draw generalizing conclusions about the nature of land use in the United States, both in the whole country and in the regional aspect. As a result, the author has obtained a generalized scientific picture of how the structure of land use in the continental part of the country (without Alaska) has changed over the course of a century in the direction from maximum to optimal use of natural resources.

scholarly journals Histological changes of the sciatic nerve in dogs after intraneural application of lidocaine--relation to the established application pressure

2005 ◽  
Vol 5 (1) ◽  
pp. 8-13 ◽  
Author(s):  
Zakira Mornjaković ◽  
Faruk Dilberović ◽  
Esad Ćosović ◽  
Kučuk-Alija Divanović ◽  
Asja Začiragić ◽  
...  
Keyword(s):  
Individual Differences ◽  
Sciatic Nerve ◽  
Inflammatory Process ◽  
Structural Changes ◽  
Proximal Part ◽  
Serial Sections ◽  
Single Application ◽  
Histological Changes ◽  
Average Value ◽  
Covering System

Histological changes of sciatic nerve in adult dogs 7 days after single application of 2% lido-caine (4 ml dose, speed of injection 3 ml/min) and measurement of the application pressure was studied, with a goal to investigate structural changes of the nerve in relation to the established pressure values. The application pressure was determined by using Bio Bench software. In intrafascicular puncture an average application pressure of 198.23 ± 52 kPa was found, and in interfascicular puncture its average value was 53.3 ± 17.9 kPa, with a note that individual differences are regularly present. Seven days after the injection, a nerve dissection was performed and serial sections covering the region of injection’s puncture and bordering proximal and distal zones, in the total length of 3 cm, were prepared. The found changed show the presence of nerves’ fibers lesions with a strong reactivity of Schwann’s cell, as well as the change of interstitial structure concerning hypercellularity and occurrence of cellular extravasation. The covering system of the nerve in the zone of epineurium manifests changes of inflammatory process and in perineurium a decomposition of lamella layers and the alteration of their tinctorial properties were noticed. A comparison of the found nerve reactivities in intra- and interfascicular application showed their one-way alteration, although the lesions were more noticeable in the conditions of intrafascicular application. The damages were mostly expressed in the zone of local application of anesthetic, than distally from it, while the damage to the structure in the proximal part is of the smallest degree.

scholarly journals ULTRASTRUCTURAL INTERRELATIONSHIPS OF NERVE PROCESSES AND SMOOTH MUSCLE CELLS IN THREE DIMENSIONS

1966 ◽  
Vol 28 (1) ◽  
pp. 37-49 ◽  
Author(s):  
J. C. Thaemert
Keyword(s):  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Osmium Tetroxide ◽  
Three Dimensional ◽  
Muscle Cells ◽  
Uranyl Acetate ◽  
Intestinal Wall ◽  
Three Dimensions ◽  
Serial Sections ◽  
Muscularis Externa

The muscularis externa of the intestinal wall of frogs was fixed in osmium tetroxide, embedded in Vestopal-W, serially sectioned for electron microscopy, and stained with uranyl acetate. A method to obtain individually mounted and properly positioned serial sections is described. The three-dimensional techniques used during the course of this investigation demonstrate that it is possible to examine carefully relatively large areas of tissue on individual serial sections with the electron microscope and subsequently to construct montages of electron micrographs of pertinent areas from each section. Several carefully rendered interrelationships of nerve processes and smooth muscle cells in three dimensions are exhibited and described. Recent studies of other neuro-effector relationships are discussed in relation to the present status of the nature and organization of the autonomic nervous system in visceral organs.

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