Light and electron microscopic studies on Myxobolus egyptica sp. nov. (Myxozoa, Myxosporea), infecting the hornlip mullet Oedalechilus labiosus from the Red Sea

2011 ◽  
Vol 56 (3) ◽  
Author(s):  
Abdel-Azeem Abdel-Baki
Keyword(s):  
Electron Microscopy ◽  
Red Sea ◽  
Direct Contact ◽  
Developmental Stages ◽  
Mature Spore ◽  
Host Cells ◽  
Electron Microscopic ◽  
Transmission Electron ◽  
Microscopic Studies ◽  
Gill Lamellae

AbstractA new myxosporean, Myxobolus egyptica sp. nov., was described from the gills of the hornlip mullet Oedalechilus labiosus, collected from the Red Sea at Al-Quseir city, Egypt. The prevalence of infection was 12/72 (16.66%). Myxobolus egyptica was identified on the basis of spore morphometry, histology and transmission electron microscopy. It was distinguished from all previously reported Myxobolus spp. by its shape, dimensions of the mature spore 10.0 ± 0.6 (9.5–10.5) μm in length, 8.5 ± 0.4 (8.0–9.0) μm in width and 8.7 ± 0.5 (8.4–9.2) μm in thickness, polar capsules, locality and host. The parasite formed intrafilamental cyst-like plasmodia. These plasmodia caused curling and atrophy of the gill lamellae. The ultrastructural analysis revealed a double-unit plasmodial membrane which was in direct contact with the host cells and had numerous vesicles. Some mitochondria were found below this membrane. The disporic pansporoblast was earliest recognizable stage of sporogenesis. Advanced developmental stages of spores and mature spores were reported.

Structure and host–actinomycete interactions in developing root nodules of Comptonia peregrina

1978 ◽  
Vol 56 (5) ◽  
pp. 502-531 ◽  
Author(s):  
William Newcomb ◽  
R. L. Peterson ◽  
Dale Callaham ◽  
John G. Torrey
Keyword(s):  
Host Cell ◽  
Root Nodules ◽  
Host Cells ◽  
Electron Microscopic ◽  
Cortical Cells ◽  
Host Cytoplasm ◽  
Transmission Electron ◽  
Microscopic Studies ◽  
Host Plasma Membrane ◽  
Soil Actinomycete

Correlated fluorescence, bright-field, transmission electron, and scanning electron microscopic studies were made on developing root nodules of Comptonia peregrina (L.) Coult. (Myricaceae) produced by a soil actinomycete which invades the root and establishes a symbiosis leading to fixation of atmospheric dinitrogen. After entering the host via a root hair infection, the hyphae of the endophyte perforate root cortical cells by local degradation of host cell walls and penetration of the host cytoplasm. The intracellular hyphae are always surrounded by host plasma membrane and a thick polysaccharide material termed the capsule. (For convenience, term intracellular refers to the endophyte being inside a Comptonia cell as distinguished from being intercellular, i.e.. between host cells, even though the former is actually extracellular as the endophyte is separated from the host cytoplasm by the host plasmalemma.) Numerous profiles of vesiculate rough endoplasmic reticulum (RER) occur near the growing hyphae. Although the capsule shows a positive Thiery reaction indicating its polysaccharide nature, the fibrillar contents of the RER do not, leaving uncertain whether the capsule results from polymers derived from the RER. Amyloplasts of the cortical cells lose their starch deposits during hyphal proliferation. The hyphae branch extensively in specific layers of the cortex, penetrating much of the host cytoplasm. At this stage, hyphal ends become swollen and form septate club-shaped vesicles within the periphery of the host cells. Lipid-like inclusions and Thiery-positive particles, possibly glycogen, are observed in the hyphae at this time. Associated with hyphal development is an increase in average host cell volume, although nuclear volume appears to remain constant. Concomitant with vesicle maturation, the mitochondrial population increases sharply, suggesting a possible relationship to vesicle function. The intimate interactions between host and endophyte during development of the symbiotic relationship are emphasized throughout.

High-Resolution SEM of Colloidal Gold Labels

1988 ◽  
Vol 46 ◽  
pp. 214-217
Author(s):  
Ralph M. Albrecht ◽  
Scott R. Simmons ◽  
James R. Prudent ◽  
Chris M. Erickson
Keyword(s):  
Electron Microscopy ◽  
Colloidal Gold ◽  
Spherical Shape ◽  
Biologically Active ◽  
Electron Microscopic ◽  
Transmission Electron ◽  
Color Density ◽  
Microscopic Studies ◽  
Backscattered Electron ◽  
Electron Imaging

Colloidal gold, conjugated to a number of biologically active molecules, including ligand and antibody, provides a useful label for light microscopy and electron microscopy. This stems, in part, from its color, density, and regular spherical shape although the ability to make the particles in a number of defined sizes, the ease of conjugation to biological material, and the retention of activity of bound molecules are also important factors.Although nearly all sizes of colloidal gold particles, from 2.0 nm on up, can be identified in transmission or high voltage transmission electron microscopy, it has generally been the larger sized particles, 15 nm and up, that have proved useful for scanning electron microscopic studies. This is due principally to the resolution limits of conventional SEMs and the need to employ backscattered electron imaging, BEI, to unambiguously define the gold labels.

Ultrastructural and Scanning Electron Microscopic Studies of Basal Cell Carcinoma

1980 ◽  
Vol 38 ◽  
pp. 728-729
Author(s):  
A. Lupulescu
Keyword(s):  
Electron Microscopy ◽  
Basal Cell Carcinoma ◽  
Cell Carcinoma ◽  
Basal Cell ◽  
Basal Cells ◽  
Electron Microscopic ◽  
Transmission Electron ◽  
Microscopic Studies ◽  
And Migration ◽  
Scanning Electron

Previously it has been shown that long-term topical application of 3-methylcholanthrene (MCA) on the rat skin induced basal cell carcinoma. These tumors are very similar to that occurring in humans and they were studied only by light microscopy.1 Transmission electron microscopy (TEM) and Scanning electron microscopy (SEM) can provide more characteristic details for the neoplastic transformation of basal cells, their cytoarchitecture and migration.

Scanning Electron Microscopy of Murine Oncornavirus Infected Cells

1974 ◽  
Vol 32 ◽  
pp. 252-253 ◽  
Author(s):  
S. Panem ◽  
P.S.D. Lin ◽  
A. V. Crewe ◽  
W. H. Kirsten
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Electron Microscopic ◽  
Viral Budding ◽  
Transmission Electron ◽  
Virion Structure ◽  
Microscopic Studies ◽  
Infected Cells ◽  
Viral Morphogenesis ◽  
Scanning Electron

Although oncornaviruses have been the subject of numerous transmission electron microscopic studies, questions concerning virion structure and the maturation of virus at the infected cell membrane remain unanswered. We have begun to study viral morphogenesis with particular emphasis on the distribution of viral budding sites and the appearance of virus during maturation using scanning electron microscopy.

A myxozoan-like parasite causing xenomas in the brain of the mole, Talpa europaea L., 1758 (Vertebrata, Mammalia)

Parasitology ◽  
2000 ◽  
Vol 121 (5) ◽  
pp. 483-492 ◽  
Author(s):  
C. FRIEDRICH ◽  
E. INGOLIC ◽  
B. FREITAG ◽  
G. KASTBERGER ◽  
V. HOHMANN ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Developmental Stages ◽  
Host Cells ◽  
Brain Capillaries ◽  
Talpa Europaea ◽  
Transmission Electron ◽  
Eukaryotic Organism ◽  
A Cell ◽  
Exact Identification ◽  
The Brain

Light and transmission electron microscopy revealed pericytes of brain capillaries of moles (Talpa europaea L., 1758) as parasitized intracellularly. These host cells were enlarged and of globular or ellipsoid shape, and incorporated a cell-within-cell sequence of primary, secondary and, rarely found, tertiary developmental stages of an eukaryotic organism. Other stages like spores were not discovered either in brain or in other organs. Due to the vertebrate host, and the parasitic cells showing the enveloped state this parasite can be classified as belonging to the Myxozoa rather than Paramyxea. Since spores, which would allow an exact identification of the parasite, could not be detected and mammals are very unusual hosts for Myxozoa, the parasite was designated a myxozoan-like organism.

Electron microscopic studies of macromolecules without appositional contrast

1971 ◽  
Vol 261 (837) ◽  
pp. 143-149 ◽  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Carbon Support ◽  
Biological Macromolecules ◽  
Large Area ◽  
Electron Microscopic ◽  
Conventional Transmission Electron Microscopy ◽  
Transmission Electron ◽  
Protein Monolayers ◽  
Microscopic Studies

Dedicated to the memory of Nicole Granboulan In pursuing electron microscopic studies of individual biomacromolecules without contrast-enhancing stains, conventional transmission electron microscopy was improved by the use of thin, large area carbon support films. Contrast of the bright-held appearance of the unstained macromolecules and complexes was strongly enhanced in a dark held obtained by insertion of a dark-held objective aperture or by tilting the condenser system. The results are exemplified by various biological macromolecules such as DNA-protein monolayers or ferritin molecules.

scholarly journals Transmission electron microscopy enables the reconstruction of the catenane and ring forms of CS2 hydrolase

2014 ◽  
Vol 50 (71) ◽  
pp. 10281-10283 ◽  
Author(s):  
Joseph Che-Yen Wang ◽  
Adam Zlotnick ◽  
Jasmin Mecinović
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Direct Evidence ◽  
Protein Assemblies ◽  
Electron Microscopic ◽  
Transmission Electron ◽  
Transmission Electron Microscopic ◽  
Microscopic Studies ◽  
Good Agreement

Transmission electron microscopic studies on CS2 hydrolase provide direct evidence for the existence of the hexadecameric catenane and octameric ring topologies. Reconstructions of both protein assemblies are in good agreement with crystallographic analyses.

A Comparative Study of Fractographic Replicas

1974 ◽  
Vol 32 ◽  
pp. 566-567
Author(s):  
Loren Anderson ◽  
Pat Pizzo ◽  
Glen Haydon
Keyword(s):  
Electron Microscopy ◽  
Electron Microscopic Examination ◽  
Direct Examination ◽  
Electron Microscopic ◽  
Reliable Technique ◽  
Service Failures ◽  
Transmission Electron ◽  
Mode Of Failure ◽  
Scanning Electron Microscopic ◽  
Scanning Electron

Transmission electron microscopy of replicas has long been used to study the fracture surfaces of components which fail in service. Recently, the scanning electron microscope (SEM) has gained popularity because it allows direct examination of the fracture surface. However, the somewhat lower resolution of the SEM coupled with a restriction on the sample size has served to limit the use of this instrument in investigating in-service failures. It is the intent of this paper to show that scanning electron microscopic examination of conventional negative replicas can be a convenient and reliable technique for determining mode of failure.

Studies of Circular DNA Using a New Electron Microscopic Technique

1973 ◽  
Vol 31 ◽  
pp. 596-597
Author(s):  
C. N. Gordon
Keyword(s):  
Electron Microscopy ◽  
Aqueous Salt Solution ◽  
Contour Length ◽  
Cleavage Surface ◽  
Mica Substrate ◽  
Electron Microscopic ◽  
Replica Technique ◽  
Circular Dna ◽  
Transmission Electron ◽  
Electron Microscopic Technique

Gordon and Kleinschmidt have described a new preparative technique for visualizing DNA by electron microscopy. This procedure, which is a modification of Hall's “mica substrate technique”, consists of the following steps: (a) K+ ions on the cleavage surface of native mica are exchanged for Al3+ ions by ion exchange. (b) The mica, with Al3+ in the exchange sites on the surface, is placed in a dilute aqueous salt solution of DNA for several minutes; during this period DNA becomes adsorbed on the surface. (c) The mica with adsorbed DNA is removed from the DNA solution, rinsed, dried and visualized for transmission electron microscopy by Hall's platinum pre-shadow replica technique.In previous studies of circular DNA by this technique, most of the molecules seen were either broken to linears or extensively tangled; in general, it was not possible to obtain suitably large samples of open extended molecules for contour length measurements.

The blister of porphyria cutanea tarda: A Scanning and Transmission Electron Microscopic study

1986 ◽  
Vol 44 ◽  
pp. 334-335
Author(s):  
Veronika Burmeister ◽  
R. Swaminathan
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Basement Membrane ◽  
Middle Age ◽  
Porphyria Cutanea Tarda ◽  
Minor Trauma ◽  
Electron Microscopic ◽  
Transmission Electron Microscopic Study ◽  
Transmission Electron ◽  
Transmission Electron Microscopic

Porphyria cutanea tarda (PCT) is a disorder of porphyrin metabolism which occurs most often during middle age. The disease is characterized by excessive production of uroporphyrin which causes photosensitivity and skin eruptions on hands and arms, due to minor trauma and exposure to sunlight. The pathology of the blister is well known, being subepidermal with epidermodermal separation, it is not always absolutely clear, whether the basal lamina is attached to the epidermis or the dermis. The purpose of our investigation was to study the attachment of the basement membrane in the blister by comparing scanning with transmission electron microscopy.

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