Time-lapse photomicrography and electron microscopy on initiation of infection of nematodes by Dactylella ellipsospora

Mycoscience ◽  
2002 ◽  
Vol 43 (4) ◽  
pp. 299-305 ◽  
Author(s):  
Ebuna Kojima ◽  
Masatoshi Saikawa
Keyword(s):  
Electron Microscopy ◽  
Time Lapse ◽  
Time Lapse Photomicrography

High-voltage Electron Microscopy of astroglial cell whole mounts

1986 ◽  
Vol 44 ◽  
pp. 316-317
Author(s):  
J.N. Turner ◽  
W.G. Shain ◽  
V. Madelian ◽  
R.A. Grassucci ◽  
D.L. Forman
Keyword(s):  
Electron Microscopy ◽  
High Voltage ◽  
Time Lapse ◽  
Astroglial Cells ◽  
High Voltage Electron Microscopy ◽  
Rat Glioma ◽  
Voltage Electron ◽  
High Voltage Electron ◽  
Nervous System Function ◽  
Beta Adrenergic Agonist

Homogeneous cultures of astroglial cells have proved useful for studying biochemical, pharmacological, and toxicological responses of astrocytes to effectors of central nervous system function. LRM 55 astroglial cells, which were derived from a rat glioma and maintained in continuous culture, exhibit a number of astrocyte properties (1-3). Stimulation of LRM 55s and astrocytes in primary cell cultures with the beta-adrenergic agonist isoproterenol results in rapid changes of morphology. Studies with time lapse video light microscopy (VLM) and high-voltage electron microscopy (HVEM) have been correlated to changes in intracellular levels of c-AMP. This report emphasizes the HVEM results.

Conidium ontogeny in hyphomycetes. The meristem arthrospores of Wallemia sebi

1973 ◽  
Vol 51 (9) ◽  
pp. 1669-1671 ◽  
Author(s):  
M. H. Hashmi ◽  
G. Morgan-Jones
Keyword(s):  
Time Lapse ◽  
Unique Type ◽  
Nuclear Distribution ◽  
Wallemia Sebi ◽  
Time Lapse Photomicrography

Conidium ontogeny in Wallemia sebi (Fr.) v. Arx is analyzed and illustrated by time-lapse photomicrography. The nuclear configurations occurring during conidiogenesis are described and subsequent nuclear distribution reported. The conidia are considered to be meristem arthrospores of a unique type.

Visual identification of synaptic boutons on living ganglion cells and of varicosities in postganglionic axons in the heart of the frog

1971 ◽  
Vol 177 (1049) ◽  
pp. 485-508 ◽  
Keyword(s):  
Electron Microscopy ◽  
Cell Body ◽  
Ganglion Cells ◽  
Surface Membrane ◽  
Time Lapse ◽  
Interatrial Septum ◽  
Optical Systems ◽  
Muscle Fibres ◽  
Electron Microscopic ◽  
Synaptic Boutons

1. Parasympathetic neurons were studied in the transparent interatrial septum of the frog ( Rana pipiens ) with light- and electron-microscopic techniques. The aim was to identify visually cellular and subcellular details in a living preparation, especially synaptic boutons on ganglion cells and the varicosities in postganglionic axons supplying the muscles of the heart. 2. The interatrial septum contains the following nervous elements: unipolar parasympathetic ganglion cells, their preganglionic vagal innervation, postganglionic sympathetic axons and sensory fibres. These structures and the nuclei of their related Schwann cells can be viewed with various optical systems, especially differential interference contrast optics. The same neural elements identified in the live preparation can be sectioned for electron microscopy. 3. Most ganglion cells are innervated by a single presynaptic axon, terminating in up to 27 synaptic boutons which on the average cover about 3.0 % of the surface of nerve cell bodies. A few scattered boutons also occur on the initial axonal portion of the ganglion cells. 4. Synaptic boutons on ganglion cells were recognized in the living unstained preparation. Their identity was confirmed by electron microscopy and by light microscopy combined with methylene blue, zinc iodide and osmium, and cholinesterase staining methods. 5. The terminal branches of postganglionic axons have numerous varicosities along their course. Some are as close as a few hundred angstroms (10 Å = 1 nm) to muscle fibres, others are many pm away. There are two types of varicosities: (i) those which contain predominantly granular vesicles characteristic of neurons releasing catecholamines, and (ii) those with predominantly agranular vesicles which belong to the cholinergic axons of septal ganglion cells. Regardless of their distance from muscle fibres, the cholinergic varicosities have the same fine structural features, including membrane thickenings, as synaptic boutons on the ganglion cells. These findings support earlier suggestions that the varicosities along postganglionic axons are a series of transmitter release sites. 6. Varicosities were observed in the live septum; their identity was confirmed by subsequent electron microscopy. Many live varicose axons were traced back to the vicinity of individual septal ganglion cells. Additional evidence that they belonged to a particular ganglion cell, and were therefore cholinergic, was obtained by injecting Procion yellow into the cell body and observing the neuron with a fluorescence microscope after the dye had spread into the axonal processes. Time lapse photography of up to 24 h showed no ‘ peristaltic ’ movement of varicosities. 7. Granular or agranular vesicles also occur along cylindrical axons within nerve bundles many pm away from muscle fibres. Like the vesicles in varicosities, they are clustered close to ‘thickenings’ in the surface membrane and belong to postganglionic nerve fibres. 8. Ganglion cells in isolated septa survive for 2 weeks or longer, still giving membrane potentials and impulses. Time lapse cinematography for up to 2 weeks after removing the septum showed that the organelles within the neurons were in motion and that a two-way traffic takes place between the cell body and axon, as commonly found in cultured neurons.

Low-magnification time lapse photomicrography

1975 ◽  
Vol 1 (2) ◽  
pp. 97-98
Author(s):  
Y. T. Chang
Keyword(s):  
Time Lapse ◽  
Time Lapse Photomicrography

Vacuolation in the human amnion cell studied by time-lapse photography and electron microscopy

1968 ◽  
Vol 102 (7) ◽  
pp. 932-948 ◽  
Author(s):  
W.D. Armstrong ◽  
J.G. Wilt ◽  
E.T. Pritchard
Keyword(s):  
Electron Microscopy ◽  
Time Lapse ◽  
Human Amnion ◽  
Amnion Cell ◽  
Time Lapse Photography

Conidium ontogeny in hyphomycetes. The genera Torulomyces Delitsch and Monocillium Saksena

1972 ◽  
Vol 50 (7) ◽  
pp. 1461-1463 ◽  
Author(s):  
M. H. Hashmi ◽  
Bryce Kendrick ◽  
G. Morgan-Jones
Keyword(s):  
Type Species ◽  
Time Lapse ◽  
Time Lapse Photomicrography

Conidium ontogeny in Torulomyces lagena Delitsch and Monocillium indicum Saksena, the type species of Torulotnyces and Monocillium respectively, is analyzed by time-lapse photomicrography. The nuclear configurations occurring during conidiogenesis are also described. Since their development and karyology are essentially identical and their morphology closely similar, we consider them congeneric. Monocillium indicum is accordingly transferred to Torulomyces.

scholarly journals Morphology of astroglial cells is controlled by beta-adrenergic receptors.

1987 ◽  
Vol 105 (5) ◽  
pp. 2307-2314 ◽  
Author(s):  
W Shain ◽  
D S Forman ◽  
V Madelian ◽  
J N Turner
Keyword(s):  
Electron Microscopy ◽  
High Voltage ◽  
Time Lapse ◽  
Receptor Activation ◽  
Intracellular Camp ◽  
Astroglial Cells ◽  
Beta Adrenergic ◽  
High Voltage Electron Microscopy ◽  
Voltage Electron ◽  
High Voltage Electron

Astroglial cells in vivo and in vitro respond to hormones, growth factors, and neurotransmitters by changing from an epithelial-like to stellate morphology. We have studied the temporal relationship between receptor activation, second messenger mobilization, and morphological changes using LRM55 astroglial cells. Maintenance of an altered morphology required continuous beta-adrenergic receptor activation. These changes appeared to be mediated by cAMP since they were elicited by its analogue, dibutyryl cAMP, and by forskolin, a direct activator of adenylate cyclase. Changes in cell morphology may require a relatively small increase in intracellular cAMP, since receptor-stimulated changes in cAMP levels were transient and peaked approximately 5 min after receptor activation while changes in morphology took at least 30 min to reach a new steady state. Time-lapse videomicroscopy and high voltage electron microscopy indicated that receptor activation resulted in a sequence of morphological events. Time-lapse observations revealed the development and enlargement of openings through the cytoplasm associated with cytoplasmic withdrawal to the perinuclear region and process formation. Higher resolution high voltage electron microscopy indicated that the transition to a stellate morphology was preceded by the appearance of two distinct cytoplasmic domains. One contained an open network of filaments and organelles. The other was characterized by short broad cytoplasmic filaments. The first domain was similar to cytoplasm in control cells while the second was associated with the development and enlargement of openings through the cytoplasm and regions of obvious cytoplasmic withdrawal.

Conidium ontogeny in hyphomycetes. The blastoconidia of Cladosporium herbarum and Torula herbarum

1973 ◽  
Vol 51 (6) ◽  
pp. 1089-1091 ◽  
Author(s):  
M. H. Hashmi ◽  
G. Morgan-Jones ◽  
Bryce Kendrick
Keyword(s):  
Time Lapse ◽  
Cladosporium Herbarum ◽  
Time Lapse Photomicrography

Conidium ontogeny in Cladosporium herbarum (Pers.) Link ex S. F. Gray and Torula herbarum (Pers.) Link ex S. F. Gray is analyzed by time-lapse photomicrography. Both fungi are shown to produce conidia holoblastically in acropetal chains.

scholarly journals Cell division in two large pennate diatoms Hantzschia and Nitzschia III. A new proposal for kinetochore function during prometaphase.

1980 ◽  
Vol 86 (2) ◽  
pp. 402-416 ◽  
Author(s):  
D H Tippit ◽  
J D Pickett-Heaps ◽  
R Leslie
Keyword(s):  
Electron Microscopy ◽  
Leading Edge ◽  
Time Lapse ◽  
Cell Types ◽  
Spindle Pole ◽  
Large Species ◽  
Conventional View ◽  
Chromosome Movements ◽  
Kinetochore Function

Prometaphase in two large species of diatoms is examined, using the following techniques: (a) time-lapse cinematography of chromosome movements in vivo; (b) electron microscopy of corresponding stages: (c) reconstruction of the microtubules (MTs) in the kinetochore fiber of chromosomes attached to the spindle. In vivo, the chromosomes independently commence oscillations back and forth to one pole. The kinetochore is usually at the leading edge of such chromosome movements; a variable time later both kinetochores undergo such oscillations but toward opposite poles and soon stretch poleward to establish stable bipolar attachment. Electron microscopy of early prometaphase shows that the kinetochores usually laterally associate with MTs that have one end attached to the spindle pole. At late prometaphase, most chromosomes are fully attached to the spindle, but the kinetochores on unattached chromosomes are bare of MTs. Reconstruction of the kinetochore fiber demonstrates that most of its MTs (96%) extend past the kinetochore and are thus apparently not nucleated there. At least one MT terminates at each kinetochore analyzed. Our interpretation is that the conventional view of kinetochore function cannot apply to diatoms. The kinetochore fiber in diatoms appears to be primarily composed of MTs from the poles, in contrast to the conventional view that many MTs of the kinetochore fiber are nucleated by the kinetochore. Similarly, chromosomes appear to initially orient their kinetochores to opposite poles by moving along MTs attached to the poles, instead of orientation effected by kinetochore MTs laterally associating with other MTs in the spindle. The function of the kinetochore in diatoms and other cell types is discussed.

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