Studies on Leukemogenic and Sarcomagenic Viruses

1970 ◽  
Vol 28 ◽  
pp. 156-157
Author(s):  
Leon Dmochowski
Keyword(s):  
Electron Microscopy ◽  
Electron Microscope ◽  
Morphological Properties ◽  
Mode Of Development ◽  
Relationship Of ◽  
The Relationship

Electron microscopy has proved to be an invaluable discipline in studies on the relationship of viruses to the origin of leukemia, sarcoma, and other types of tumors in animals and man. The successful cell-free transmission of leukemia and sarcoma in mice, rats, hamsters, and cats, interpreted as due to a virus or viruses, was proved to be due to a virus on the basis of electron microscope studies. These studies demonstrated that all the types of neoplasia in animals of the species examined are produced by a virus of certain characteristic morphological properties similar, if not identical, in the mode of development in all types of neoplasia in animals, as shown in Fig. 1.

scholarly journals DNA AND THE FINE STRUCTURE OF SYNAPTIC CHROMOSOMES IN THE DOMESTIC ROOSTER (GALLUS DOMESTICUS)

1964 ◽  
Vol 23 (1) ◽  
pp. 63-78 ◽  
Author(s):  
James R. Coleman ◽  
Montrose J. Moses
Keyword(s):  
Electron Microscopy ◽  
Heavy Metal ◽  
Fine Structure ◽  
Electron Microscope ◽  
Meiotic Prophase ◽  
Gallus Domesticus ◽  
Feulgen Staining ◽  
Synaptinemal Complex ◽  
Relationship Of ◽  
The Relationship

The indium trichloride method of Watson and Aldridge (38) for staining nucleic acids for electron microscopy was employed to study the relationship of DNA to the structure of the synaptinemal complex in meiotic prophase chromosomes of the domestic rooster. The selectivity of the method was demonstrated in untreated and DNase-digested testis material by comparing the distribution of indium staining in the electron microscope to Feulgen staining and ultraviolet absorption in thicker sections seen with the light microscope. Following staining by indium, DNA was found mainly in the microfibril component of the synaptinemal complex. When DNA was known to have been removed from aldehyde-fixed material by digestion with DNase, indium stainability was also lost. However, staining of the digested material with non-selective heavy metal techniques demonstrated the presence of material other than DNA in the microfibrils and showed that little alteration in appearance of the chromosome resulted from DNA removal. The two dense lateral axial elements of the synaptinemal complex, but not the central one to any extent, also contained DNA, together with non-DNA material.

Binding of Tetrahymena dynein to axonemes of Marsilea vestita lacking the outer dynein arm

1985 ◽  
Vol 73 (1) ◽  
pp. 299-310
Author(s):  
J.S. Hyams
Keyword(s):  
Electron Microscopy ◽  
Polyacrylamide Gel Electrophoresis ◽  
Valuable Insight ◽  
Marsilea Vestita ◽  
Thin Section Electron Microscopy ◽  
Section Electron ◽  
And Function ◽  
Relationship Of ◽  
The Relationship ◽  
Insight Into

Axonemes from the heterosporous water fern Marsilea vestita were fixed in the presence of tannic acid and examined by thin-section electron microscopy. Transverse sections revealed the normal 9+2 configuration except for the absence of the outer of the two dynein arms. Both arms were normally preserved in parallel preparations of Chlamydomonas axonemes. Isolated dynein from the ciliated protozoon Tetrahymena bound to Marsilea axonemes at the site normally occupied by the outer arm. Dynein binding was partially reversed by ATP as judged by both electron microscopy and polyacrylamide gel electrophoresis. This system should provide a valuable insight into the biochemistry and function of the inner dynein arm and the relationship of the two arms to motility in more conventionally equipped axonemes.

scholarly journals The Relationship of Bartonella Bacilliformis to the Red Blood Cell as Revealed by Electron Microscopy

Blood ◽  
1969 ◽  
Vol 33 (5) ◽  
pp. 708-716 ◽  
Author(s):  
MANUEL CUADRA ◽  
JUAN TAKANO
Keyword(s):  
Electron Microscopy ◽  
Blood Cell ◽  
Red Cells ◽  
Red Cell ◽  
Bartonella Bacilliformis ◽  
Coccoid Form ◽  
Blood Smears ◽  
Ultrathin Sections ◽  
Relationship Of ◽  
The Relationship

Abstract Ultrathin sections of erythrocytosis parasitized by B. bacilliformis have been examined by electron microscopy. The study concerns three Oroya Fever patients whose blood smears showed B. bacilliformis predominantly in its coccoid form as parastizing over 70 per cent of the red cells. B. bacilliformis is termed as a bacterium in its structure and appears to lie not only on the host red cells but predominantly within them. Therefore, this organism might have the capacity to penetrate into the red cell. This finding does not change the basic concept regarding the mechanism of the anemia of Oroya Fever.

scholarly journals THE EFFECT OF INSULIN, ALLOXAN DIABETES, AND ANOXIA ON THE ULTRASTRUCTURE OF THE RAT HEART

1962 ◽  
Vol 15 (3) ◽  
pp. 509-523 ◽  
Author(s):  
David N. Orth ◽  
Howard E. Morgan
Keyword(s):  
Electron Microscopy ◽  
Glucose Transport ◽  
Alloxan Diabetes ◽  
Diabetic Rats ◽  
Cytoplasmic Vesicles ◽  
Lipid Inclusions ◽  
Line Level ◽  
Relationship Of ◽  
The Relationship

Hearts from normal and alloxan diabetic rats were perfused in vitro with a bicarbonate-buffered medium containing glucose. Transport of glucose through the cell membrane was stimulated with insulin or by induction of anaerobiosis. The organs were rapidly fixed and examined by electron microscopy. Transport stimulation was not associated with any increase in the number of sarcolemmal invaginations or subsarcolemmal cytoplasmic vesicles. It was concluded that glucose transport and the effects of insulin or anoxia do not involve pinocytosis. The relationship of pinocytosis to glucose transport is discussed. The appearance of numerous lipid inclusions at the Z line level of the sarcomeres in the diabetic and anoxic myocardia is described.

scholarly journals CENTROSOMES AND MICROTUBULES DURING MEIOSIS IN THE MUSHROOM BOLETUS RUBINELLUS

1971 ◽  
Vol 50 (3) ◽  
pp. 737-745 ◽  
Author(s):  
David J. McLaughlin
Keyword(s):  
Electron Microscope ◽  
Longitudinal Axis ◽  
Spindle Pole ◽  
Middle Part ◽  
Prophase I ◽  
Cytoplasmic Microtubules ◽  
Oriented Parallel ◽  
Relationship Of ◽  
The Relationship

The double centrosome in the basidium of Boletus rubinellus has been observed in three planes with the electron microscope at interphase preceding nuclear fusion, at prophase I, and at interphase I. It is composed of two components connected by a band-shaped middle part. At anaphase I a single, enlarged centrosome is found at the spindle pole, which is attached to the cell membrane. Microtubules mainly oriented parallel to the longitudinal axis of the basidium are present at prefusion, prophase I and interphase I. Cytoplasmic microtubules are absent when the spindle is present. The relationship of the centrosome in B. rubinellus to that in other organisms and the role of the cytoplasmic microtubules are discussed.

scholarly journals THE FINE STRUCTURAL LOCALIZATION OF ACETYLCHOLINESTERASE AT THE MYONEURAL JUNCTION

1962 ◽  
Vol 12 (2) ◽  
pp. 247-262 ◽  
Author(s):  
Russell J. Barrnett
Keyword(s):  
Electron Microscopy ◽  
Plasma Membrane ◽  
Axon Terminal ◽  
Myoneural Junction ◽  
Cytochemical Localization ◽  
Structural Localization ◽  
Terminal Axon ◽  
Esterolytic Activity ◽  
Relationship Of ◽  
The Relationship

A study of the cytochemical localization of acetylcholiriesterase activity, combining histochemistry with electron microscopy, showed that the final product of the reaction, which was deposited at or near enzyme sites, occurred at four places in the myoneural junction. These included: plasma membrane of the muscle covering the junctional folds, the primary and secondary synaptic clefts, parts of the plasma membrane covering the axon terminal, and vesicular structures in the terminal axoplasm. No reaction occurred in the presence of 10-4 eserine or DFP, whereas 10-5 DFP inhibited the reaction at all sites except in the vesicles of the terminal axon. These findings are discussed with reference to the histochemical method used and to the occurrence of esterolytic activity in the vesicles, as well as to some of the current hypotheses concerning the relationship of the site of acetylcholinesterase and synaptic transmission.

Morphology of the elongate sensillum placodeum on the antennae of Aphidius smithi (Hymenoptera: Aphidiidae)

1978 ◽  
Vol 56 (4) ◽  
pp. 519-525 ◽  
Author(s):  
J. H. Borden ◽  
A. Rose ◽  
R. J. Chorney
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Host Finding ◽  
Dendritic Branch ◽  
Tormogen Cell ◽  
Dendritic Branches ◽  
Relationship Of ◽  
The Relationship ◽  
Cuticular Surface ◽  
Scanning Electron

Elongate placoid sensilla were present on all 20 flagellar segments in five male Aphidius smithi and all but the basal 1 of 17 segments in five females. They are oriented longitudinally, approximately equidistant around the circumference of a segment. Scanning electron microscopy of the internal cuticular surface disclosed lamellae which divide the sensillum into lateral and median channels. Many transverse ridges are present in the ceiling of the median channel. Unlike other species, there is no cuticular floor of the sensillum. Numerous nerve cell bodies in the subcuticular tissue give rise to dendritic processes, a ciliary region, and a region of dendritic branches which lie parallel to each other within the 1-μm-wide median channel underneath the 0.1- to 0.25-μm-thick dome. Each dendritic branch is composed of a neurotubule surrounded by a plasma membrane. The ascending dendrites are flanked by the microvilli of the trichogen cell. A tormogen cell encloses the trichogen cell and extends into the lateral channels of the sensillum. The relationship of minute pores in the dome with the underlying dendritic branches is unclear. The hypothesis is advanced that the sensilla may be involved in host finding through perception of infrared radiation.

The relationship of larval shell morphology to mode of development in marine prosobranch gastropods

1990 ◽  
Vol 70 (3) ◽  
pp. 611-637 ◽  
Author(s):  
Gail M. Lima ◽  
Richard A. Lutz
Keyword(s):  
Shell Morphology ◽  
Larval Shell ◽  
Crepidula Fornicata ◽  
Busycon Canaliculatum ◽  
Littorina Obtusata ◽  
Urosalpinx Cinerea ◽  
Planktotrophic Larvae ◽  
Mode Of Development ◽  
Relationship Of ◽  
The Relationship

The larval shell of molluscs contains a preserved record of the organism's growth and developmental history. Many investigators have utilized the information recorded in the larval shell morphology to infer mode of development.Marine prosobranch gastropods were collected from intertidal sites from Maine to Florida and were cultured in the laboratory. Scanning electron microscopy was used to document the relationship of larval shell morphology to development. Four species with planktotrophic larvae, Crepidula fornicata, Crepidula plana, Cerithium atratum and Ilyanassa obsoleta, and four species with non-planktotrophic development, Crepidula convexa, Littorina obtusata, Busycon canaliculatum and Urosalpinx cinerea, were successfully reared through metamorphosis.

Zygospores of the Harpellales: an ultrastructural study

1977 ◽  
Vol 55 (24) ◽  
pp. 3099-3110 ◽  
Author(s):  
S. T. Moss ◽  
R. W. Lichtwardt
Keyword(s):  
Electron Microscope ◽  
Transmission Electron Microscope ◽  
Ultrastructural Study ◽  
Storage Materials ◽  
Transmission Electron ◽  
Relationship Of ◽  
The Relationship ◽  
Thickened Wall

Structure of zygospores, their zygosporophores, and conjugants in Harpella melusinae, Trichozygospora chironomidarum, Genistellospora homothallica, and Zygopolaris ephemeridarum is described from light and transmission electron microscope studies. Possession of a thickened wall, presence of storage materials, and formation after hyphal conjugation supports the interpretation of these as zygospores. The relationship of the harpellaceous zygospores to those of other members of the Zygomycotina is discussed.

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