Chlorophyll- and anthocyanin-rich cell organelles affect light scattering in apple skin

A study of the molecular–cellular interface in visual photoreceptors by light scattering photometry

Canadian Journal of Chemistry ◽

10.1139/v85-320 ◽

1985 ◽

Vol 63 (7) ◽

pp. 1933-1939 ◽

Cited By ~ 1

Author(s):

T. Borys ◽

S. Deshpande ◽

R. Jones ◽

E. W. Abrahamson

Keyword(s):

Light Scattering ◽

Structural Changes ◽

Time Range ◽

Relaxation Techniques ◽

Cell Organelles ◽

Whole Cells ◽

Cellular Events ◽

Molecular Events ◽

Cytological Changes ◽

Non Destructive

The correlation of molecular events with structural changes within the cell requires a non-destructive relaxation technique that can be adapted to measure such cellular changes in a time range of milliseconds to minutes. Light scattering relaxation techniques have proved useful for such studies as they can often be measured simultaneously or in parallel with absorption or fluorescence spectral changes characterizing molecular or macromolecular processes. Such techniques are proving useful in the study of photobiological processes such as visual photoreception where specific cytological changes produced photochemically can be effected by alternate controlled perturbations such as osmotic shrinking or swelling of cell organelles and (or) whole cells. This paper illustrates how light scattering relaxation spectrophotometry can be applied to the correlation of molecular and cellular events in visual photoreceptors.

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Ultrastructure of Giant Mitochondria and Their Inclusions in Schwann Cells of Bovine Splenic Nerve

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100050986 ◽

1974 ◽

Vol 32 ◽

pp. 194-195

Author(s):

Å. Thureson-Klein

Keyword(s):

Schwann Cells ◽

Cell Organelles ◽

Giant Mitochondria ◽

Matrix Density ◽

Physiological Conditions ◽

Unmyelinated Axons ◽

Internal Structures ◽

Structural Abnormalities ◽

Cytotoxic Compounds ◽

Cell Components

Giant mitochondria of various shapes and with different internal structures and matrix density have been observed in a great number of tissues including nerves. In most instances, the presence of giant mitochondria has been associated with a known disease or with abnormal physiological conditions such as anoxia or exposure to cytotoxic compounds. In these cases degenerative changes occurred in other cell organelles and, therefore the giant mitochondria also were believed to be induced structural abnormalities.Schwann cells ensheating unmyelinated axons of bovine splenic nerve regularly contain giant mitochondria in addition to the conventional smaller type (Fig. 1). These nerves come from healthy inspected animals presumed not to have been exposed to noxious agents. As there are no drastic changes in the small mitochondria and because other cell components also appear reasonably well preserved, it is believed that the giant mitochondria are normally present jin vivo and have not formed as a post-mortem artifact.

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Cell Fine Structure as Revealed in Dessicator-Dried Resinless Sections

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100099532 ◽

1981 ◽

Vol 39 ◽

pp. 622-623

Author(s):

R. P. Becker ◽

J. J. Wolosewick ◽

J. Ross-Stanton

Keyword(s):

Fine Structure ◽

Tannic Acid ◽

Three Dimensional ◽

Albino Rats ◽

Cell Organelles ◽

Vascular Perfusion ◽

Thin Sections ◽

Carbon Coated ◽

Embedding Medium ◽

Polyethylene Glycol 6000

Methodology has been introduced recently which allows transmission and scanning electron microscopy of cell fine structure in semi-thin sections unencumbered by an embedding medium. Images obtained from these “resinless” sections show a three-dimensional lattice of microtrabeculfee contiguous with cytoskeletal structures and membrane-bounded cell organelles. Visualization of these structures, especially of the matiiDra-nous components, can be facilitated by employing tannic acid in the fixation step and dessicator drying, as reported here.Albino rats were fixed by vascular perfusion with 2% glutaraldehyde or 1.5% depolymerized paraformaldehyde plus 2.5% glutaraldehyde in 0.1M sodium cacodylate (pH 7.4). Tissues were removed and minced in the fixative and stored overnight in fixative containing 4% tannic acid. The tissues were rinsed in buffer (0.2M cacodylate), exposed to 1% buffered osmium tetroxide, dehydrated in ethyl alcohol, and embedded in pure polyethylene glycol-6000 (PEG). Sections were cut on glass knives with a Sorvall MT-1 microtome and mounted onto poly-L-lysine, formvar-carbon coated grids while submerged in a solution of 95% ethanol containing 5% PEG.

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Drug Induced Changes in Cell Organelles

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100100299 ◽

1968 ◽

Vol 26 ◽

pp. 110-111

Author(s):

Sarah A. Luse

Keyword(s):

Clinical Medicine ◽

Cell Organelles ◽

Riboflavin Deficiency ◽

Drug Induced ◽

New Era ◽

Health And Disease ◽

In The Beginning ◽

Cellular Pathology ◽

Induced Changes ◽

The Impact

In the mid-nineteenth century Virchow revolutionized pathology by introduction of the concept of “cellular pathology”. Today, a century later, this term has increasing significance in health and disease. We now are in the beginning of a new era in pathology, one which might well be termed “organelle pathology” or “subcellular pathology”. The impact of lysosomal diseases on clinical medicine exemplifies this role of pathology of organelles in elucidation of disease today.Another aspect of cell organelles of prime importance is their pathologic alteration by drugs, toxins, hormones and malnutrition. The sensitivity of cell organelles to minute alterations in their environment offers an accurate evaluation of the site of action of drugs in the study of both function and toxicity. Examples of mitochondrial lesions include the effect of DDD on the adrenal cortex, riboflavin deficiency on liver cells, elevated blood ammonia on the neuron and some 8-aminoquinolines on myocardium.

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Ultrastructural Changes in the Root Meristem Cells of Rubus Chamaemorus L. (Cloudberry)

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100116437 ◽

1975 ◽

Vol 33 ◽

pp. 562-563

Author(s):

Arya K. Bal

Keyword(s):

Root Meristem ◽

Uranyl Acetate ◽

Particulate Material ◽

Ultrastructural Changes ◽

Cell Organelles ◽

Cytoplasmic Matrix ◽

Golgi Membranes ◽

Rubus Chamaemorus ◽

Dense Substance ◽

Ultrathin Sections

In the course of studies in the root meristem tissue of Rubus chamaemorus L. some important changes in the ultrastructural morphology were observed during the initiation of senescence at the end of the growing season.Root meristems were collected from naturally growing healthy populations of Cloudberry plants, and fixed in Karnovsky's mixture or in 2.5% glutaraldehyde in phosphate buffer. The samples were osmicated, dehydrated following usual methods and embedded in Epon. Ultrathin sections were stained in uranyl acetate and lead citrate.Figure 1 shows part of a dense cell in the meristem. The electron density of these cells is due to large amounts of a particulate material in the cytoplasmic matrix. The smallest particle seen in electron micrographs is about 40 A, although larger aggregates are also found, which remain randomly distributed in association with various cell organelles. Dense substance has been found associated with golgi membranes, proplastids, vacuoles and microtubules (Fig. 2).

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Actin and α-tubulin immuno-EM labelings reveal differences in intra versus interphotoreceptor matrix

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100159874 ◽

1990 ◽

Vol 48 (3) ◽

pp. 466-467

Author(s):

Matti Järvilehto ◽

Riitta Harjula

Keyword(s):

Compound Eye ◽

Frozen Section ◽

Smooth Muscle Actin ◽

Photoreceptor Cells ◽

Immune Serum ◽

Cell Organelles ◽

Calliphora Erythrocephala ◽

Optical Axes ◽

Interphotoreceptor Matrix ◽

Similar Kind

The photoreceptor cells in the compound eyes of higher diptera are clustered in groups (ommatidia) of eight receptor cells. The cells from six adjacent ommatidia are organized into optical units, neuro-ommatia sharing the same visual field. In those ommatidia the optical axes of the photopigment containing structures (rhabdomeres) are parallel. The rhabdomeres of the photoreceptor cells are separated from each other by an interstitial i.e innerommatidial space (IOS). In the photoreceptor cell body, besides of the normal cell organelles, a cellular matrix is a structurally apparent component. Similar kind of reticular formation is also found in the IOS containing some unidentified filamentary substance, of which composition and functional significance for optical properties of vision is the aim of this report.The prefixed (2% PA + 0.2% GA in 0.1-n phosphate buffer, pH 7.4, for 1h), frozen section blocks of the compound eye of the blowfly (Calliphora erythrocephala) were prepared by immuno-cryo-techniques. The ultrathin cryosections were incubated with antibodies of monoclonal α-tubulin and polyclonal smooth muscle actin. Control labelings of excess of antigen, non-immune serum and non-present antibody were perforated.

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