Visualizing the Node and Notochordal Plate In Gastrulating Mouse Embryos Using Scanning Electron Microscopy and Whole Mount Immunofluorescence

The host–predator relationship of the myceliophagous nematode Aphelenchus avenae Bastian and the predaceous hyphomycete Dactylaria Candida (Nees) Sacc. was investigated using scanning electron microscopy of whole-mount preparations and transmission electron microscopy of ultrathin resin (Spurr) sections. Trapping knobs and knobs with associated hyphae were found to be effective nematode-trapping agents. The ultrastructure of the trapping apparatus and of the nematodes and hyphae during the infection process is reported herein, as is the phenomenon of postinfection 'breakout.' Nonconstricting rings were not observed during this study.

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Microscopic observations on the trapping of nematodes by the predaceous fungus Dactylella cionopaga

Canadian Journal of Botany ◽

10.1139/b84-101 ◽

1984 ◽

Vol 62 (4) ◽

pp. 674-679 ◽

Cited By ~ 11

Author(s):

J. A. Dowsett ◽

J. Reid ◽

A. A. Hopkin

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Transmission Electron Microscopy ◽

Morphological Development ◽

Transmission Electron ◽

Whole Mount ◽

Aphelenchus Avenae ◽

The One ◽

Scanning Electron

The host–predator relationship between the predaceous hyphomycete Dactylella cionopaga Drechs. and the myceliophagous parthenogenetic nematode Aphelenchus avenae Bastian was investigated using interference-contrast and scanning electron microscopy of whole-mount preparations and transmission electron microscopy of ultrathin (Spurr) sections. The one-, two-, three-, or more-celled adhesive trapping structures of this fungus were found to be effective predatory mechanisms at all stages of their morphological development. The trapping structures, mode of capture, and penetration by D. cionopaga were compared with the adhesive knobs, constricting rings, and adhesive hyphal networks of Dactylaria species reported on previously.

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Light and scanning electron microscopy of attachment organs of three monogeneans (Monogenoidea: Polyopisthocotylea)

Canadian Journal of Zoology ◽

10.1139/z74-022 ◽

1974 ◽

Vol 52 (2) ◽

pp. 183-187 ◽

Cited By ~ 3

Author(s):

K. A. Wright ◽

A. Dechtiar

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Light Microscopy ◽

Light Microscope ◽

The Body ◽

Single Pair ◽

The Third ◽

Gland Cells ◽

Whole Mount ◽

Scanning Electron

The anterior and posterior attachment organs of three species of monogeneans, Diclybothrium armatum Leuckart, 1835, Neodiscocotyle carpioditis Dechtiar, 1967, and Mazocraeoides olentangiensis Sroufe, 1958, were examined in whole-mount light-microscope preparations, and by scanning electron microscopy (SEM). Bothria with openings of gland cells were identified anterior to the oral opening in D. armatum, but sucker-like units evident in light microscopy were not seen by SEM in N. carpioditis and M. olentangiensis as these are apparently internal developments. Holdfast units of the opisthaptor of the three species are of three distinct forms: spring-like clamps in D. armatum, muscular clamps in M. olentangiensis. and suckers with sclerotized rims in N. carpioditis. Hooks in the opisthaptor appendage of D. armatum all function to form a C-shaped double-pronged hook unit. Two of the three pairs of hooks in the posterior end of M. olentangiensis project slightly from the body, while the third pair in this species and the single pair of hooks in N. carpioditis are entirely internal, probably non-functional and vestigial.

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Pathogenesis of Human Hair Defects

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010005007x ◽

1974 ◽

Vol 32 ◽

pp. 12-13

Author(s):

P.S. Porter ◽

T. Aoyagi ◽

R. Matta

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Human Hair ◽

Standard Techniques ◽

Scanning Electron

Using standard techniques of scanning electron microscopy (SEM), over 1000 human hair defects have been studied. In several of the defects, the pathogenesis of the abnormality has been clarified using these techniques. It is the purpose of this paper to present several distinct morphologic abnormalities of hair and to discuss their pathogenesis as elucidated through techniques of scanning electron microscopy.

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Ultrastructural Analysis of the Salivary Glands of Gromphadorhina Portentosa (Schaum)

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100080614 ◽

1977 ◽

Vol 35 ◽

pp. 638-639

Author(s):

P.J. Dailey

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Salivary Glands ◽

Secretory Vesicles ◽

The Past ◽

Transmission Electron ◽

Means Of Transmission ◽

Gromphadorhina Portentosa ◽

Scanning Electron ◽

Topographical Relief

The structure of insect salivary glands has been extensively investigated during the past decade; however, none have attempted scanning electron microscopy (SEM) in ultrastructural examinations of these secretory organs. This study correlates fine structure by means of SEM cryofractography with that of thin-sectioned epoxy embedded material observed by means of transmission electron microscopy (TEM).Salivary glands of Gromphadorhina portentosa were excised and immediately submerged in cold (4°C) paraformaldehyde-glutaraldehyde fixative1 for 2 hr, washed and post-fixed in 1 per cent 0s04 in phosphosphate buffer (4°C for 2 hr). After ethanolic dehydration half of the samples were embedded in Epon 812 for TEM and half cryofractured and subsequently critical point dried for SEM. Dried specimens were mounted on aluminum stubs and coated with approximately 150 Å of gold in a cold sputtering apparatus.Figure 1 shows a cryofractured plane through a salivary acinus revealing topographical relief of secretory vesicles.

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Two- or three-way observations of the identical cell elements within the same sections by LM, TEM and/or SEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100081279 ◽

1978 ◽

Vol 36 (2) ◽

pp. 82-83 ◽

Cited By ~ 1

Author(s):

Nakazo Watari ◽

Yasuaki Hotta ◽

Yoshio Mabuchi

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Transmission Electron Microscopy ◽

Fine Structure ◽

Light Microscopy ◽

Thin Sections ◽

Transmission Electron ◽

Identical Cell ◽

Electron Microscopes ◽

Scanning Electron

It is very useful if we can observe the identical cell elements within the same sections by light microscopy (LM), transmission electron microscopy (TEM) and/or scanning electron microscopy (SEM) sequentially, because, the cell fine structure can not be indicated by LM, while the color is; on the other hand, the cell fine structure can be very easily observed by EM, although its color properties may not. However, there is one problem in that LM requires thick sections of over 1 μm, while EM needs very thin sections of under 100 nm. Recently, we have developed a new method to observe the same cell elements within the same plastic sections using both light and transmission (conventional or high-voltage) electron microscopes.In this paper, we have developed two new observation methods for the identical cell elements within the same sections, both plastic-embedded and paraffin-embedded, using light microscopy, transmission electron microscopy and/or scanning electron microscopy (Fig. 1).

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Spontaneous Cataract in Nude Athymic Mice

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100079991 ◽

1977 ◽

Vol 35 ◽

pp. 512-513

Author(s):

Ronald H. Bradley ◽

R. S. Berk ◽

L. D. Hazlett

Keyword(s):

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Nude Mouse ◽

Cellular Immunity ◽

Phosphate Buffer ◽

Osmium Tetroxide ◽

Athymic Mice ◽

Transmission Microscopy ◽

Mouse Lens ◽

Scanning Electron

The nude mouse is a hairless mutant (homozygous for the mutation nude, nu/nu), which is born lacking a thymus and possesses a severe defect in cellular immunity. Spontaneous unilateral cataractous lesions were noted (during ocular examination using a stereomicroscope at 40X) in 14 of a series of 60 animals (20%). This transmission and scanning microscopic study characterizes the morphology of this cataract and contrasts these data with normal nude mouse lens.All animals were sacrificed by an ether overdose. Eyes were enucleated and immersed in a mixed fixative (1% osmium tetroxide and 6% glutaraldehyde in Sorenson's phosphate buffer pH 7.4 at 0-4°C) for 3 hours, dehydrated in graded ethanols and embedded in Epon-Araldite for transmission microscopy. Specimens for scanning electron microscopy were fixed similarly, dehydrated in graded ethanols, then to graded changes of Freon 113 and ethanol to 100% Freon 113 and critically point dried in a Bomar critical point dryer using Freon 13 as the transition fluid.

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