Visualization of the Structure of the Rat Oocyte by Scanning Electron Microscopy

Osmium Tetroxide ◽

Transmission Electron ◽

Electron Microscopes ◽

Preparation Techniques ◽

Scanning Electron ◽

Single Ovary ◽

Sem Studies

Mammalian oocytes have been well studied with the light and the transmission electron microscopes(1,2). Glutaraldehyde and osmium tetroxide, which offer excellent fixation have certain limitations when used for SEM studies of rat ovaries. These fixatives require very small specimens for penetration, but such small specimens provide only a few intact oocytes for SEM observations. However, for meaningful observation of the changes brought about by various hormone treatments on the oocytes, a maximum number of oocytes must be available frcm a single ovary. Also, aldehyde and OSO4 fixed tissues are not easy to cut into smooth halves. This report cctnmuni- cates preparation techniques that yield useful SEM of the oocyte and associated structures of rat ovaries.Rat ovaries were dissected out and immediately placed in Bouin's fluid for 24 hours at rocm temperature. After fixation each ovary was cut into two halves with a sharp blade and kept in 70% alcohol overnight.

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 ◽

Transmission Electron Microscopy ◽

Fine Structure ◽

Light Microscopy ◽

Thin Sections ◽

Transmission Electron ◽

Identical Cell ◽

Electron Microscopes ◽

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).

Scanning and Transmission Microscopy of Nematocyst Batteries in Epitheliomuscular Cells of Hydra

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100066097 ◽

1971 ◽

Vol 29 ◽

pp. 410-411 ◽

Cited By ~ 1

Author(s):

Jane A. Westfall ◽

S. Yamataka ◽

Paul D. Enos

Keyword(s):

Electron Microscopy ◽

Osmium Tetroxide ◽

External Surface ◽

Three Dimensional ◽

Surface Structures ◽

Transmission Microscopy ◽

Transmission Electron ◽

Freeze Dried ◽

Scanning electron microscopy (SEM) provides three dimensional details of external surface structures and supplements ultrastructural information provided by transmission electron microscopy (TEM). Animals composed of watery jellylike tissues such as hydras and other coelenterates have not been considered suitable for SEM studies because of the difficulty in preserving such organisms in a normal state. This study demonstrates 1) the successful use of SEM on such tissue, and 2) the unique arrangement of batteries of nematocysts within large epitheliomuscular cells on tentacles of Hydra littoralis.Whole specimens of Hydra were prepared for SEM (Figs. 1 and 2) by the fix, freeze-dry, coat technique of Small and Màrszalek. The specimens were fixed in osmium tetroxide and mercuric chloride, freeze-dried in vacuo on a prechilled 1 Kg brass block, and coated with gold-palladium. Tissues for TEM (Figs. 3 and 4) were fixed in glutaraldehyde followed by osmium tetroxide. Scanning micrographs were taken on a Cambridge Stereoscan Mark II A microscope at 10 KV and transmission micrographs were taken on an RCA EMU 3G microscope (Fig. 3) or on a Hitachi HU 11B microscope (Fig. 4).

Microstructure of Polycrystalline Sic Containing Excess Si after Neutron Irradiation

MRS Proceedings ◽

10.1557/proc-2-527 ◽

1980 ◽

Vol 2 ◽

Author(s):

S.D. Harrison ◽

J.C. Corelli

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Grain Boundaries ◽

Neutron Irradiation ◽

Black Spot ◽

Excess Silicon ◽

Transmission Electron ◽

Scanning Electron ◽

Sem Studies

ABSTRACTThe microstructure of commercially available reactionbonded polycrystalline SiC containing 8–10 wt% excess silicon was studied after irradiation by reactor neutrons uitlizing transmission electron microscopy (TEM) and scanning electron microscopy (SEM). For TEM studies on samples irradiated below 473°K we observe dislocation tangles near grain boundaries or impurities plus isolated dislocations throughout the remainder of the grain, whereas for irradiation temperatures of ≈3730°K the material exhibits copious quantities of “black spot” defects (2–5nm size) and a lower concentration of tangles than 473°K irradiation. The SEM studies of surfaces of samples fractured at 1473°K indicate that the mode of fracture is predominantly transgranular.

Comparative morphology of zebra (Dreissena polymorpha) and quagga (Dreissena bugensis) mussel sperm: light and electron microscopy

Canadian Journal of Zoology ◽

10.1139/z96-093 ◽

1996 ◽

Vol 74 (5) ◽

pp. 809-815 ◽

Cited By ~ 11

Author(s):

G. K. Walker ◽

C. A. Edwards ◽

M. G. Black

Keyword(s):

Electron Microscopy ◽

Dreissena Polymorpha ◽

Osmium Tetroxide ◽

Light And Electron Microscopy ◽

Comparative Morphology ◽

Dreissena Bugensis ◽

Transmission Electron ◽

Contrast Microscopy ◽

Adult zebra (Dreissena polymorpha) and quagga (Dreissena bugensis) mussels were induced to release large quantities of live spermatozoa by the administration of 5-hydroxytryptamine (serotonin). Sperm were photographed alive using phase-contrast microscopy and were fixed subsequently with glutaraldehyde followed by osmium tetroxide for eventual examination by transmission or scanning electron microscopy. The sperm of both genera are of the ect-aquasperm type. Their overall dimensions and shape allow for easy discrimination at the light and scanning electron microscopy level. Transmission electron microscopy of the cells reveals a barrel-shaped nucleus in zebra mussel sperm and an elongated nucleus in quagga mussel sperm. In both species, an acrosome is cradled in a nuclear fossa. The ultrastructure of the acrosome and axial body, however, is distinctive for each species. The structures of the midpiece are shown, including a unique mitochondrial "skirt" that includes densely packed parallel cristae and extends in a narrow sheet from the mitochondria.

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 ◽

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.

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 ◽

Nude Mouse ◽

Cellular Immunity ◽

Phosphate Buffer ◽

Osmium Tetroxide ◽

Athymic Mice ◽

Transmission Microscopy ◽

Mouse Lens ◽

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.

Copper Localization in Cirrhotic Rat Liver by Scanning Electron Microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100062099 ◽

1969 ◽

Vol 27 ◽

pp. 38-39 ◽

Cited By ~ 1

Author(s):

J. C. Russ ◽

E. McNatt

Keyword(s):

Electron Microscopy ◽

Endoplasmic Reticulum ◽

Electron Microscope ◽

Copper Acetate ◽

Lead Citrate ◽

Dense Bodies ◽

Transmission Electron ◽

Electron Mode ◽

In order to study the retention of copper in cirrhotic liver, rats were made cirrhotic by carbon tetrachloride inhalation twice weekly for three months and fed 0.2% copper acetate ad libidum in drinking water for one month. The liver tissue was fixed in osmium, sectioned approximately 2000 Å thick, and stained with lead citrate. The section was examined in a scanning electron microscope (JEOLCO JSM-2) in the transmission electron mode.Figure 1 shows a typical area that includes a red blood cell in a sinusoid, a disse, and a portion of the cytoplasm of a hepatocyte which contains several mitochondria, peribiliary dense bodies, glycogen granules, and endoplasmic reticulum.

Identification of calcium oxalate crystals in dried or fixed tobacco leaf

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100111550 ◽

1984 ◽

Vol 42 ◽

pp. 288-289

Author(s):

Vicki L. Baliga ◽

Mary Ellen Counts

Keyword(s):

Electron Microscopy ◽

Calcium Oxalate ◽

Growth And Development ◽

Polarized Light ◽

Calcium Oxalate Crystals ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Calcium is an important element in the growth and development of plants and one form of calcium is calcium oxalate. Calcium oxalate has been found in leaf seed, stem material plant tissue culture, fungi and lichen using one or more of the following methods—polarized light microscopy (PLM), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and x-ray diffraction.Two methods are presented here for qualitatively estimating calcium oxalate in dried or fixed tobacco (Nicotiana) leaf from different stalk positions using PLM. SEM, coupled with energy dispersive x-ray spectrometry (EDS), and powder x-ray diffraction were used to verify that the crystals observed in the dried leaf with PLM were calcium oxalate.

Comparative Study of the Fine Morphology of Sensory Receptors in Aspidogaster conchicola and Cotylaspis insignis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100094000 ◽

1972 ◽

Vol 30 ◽

pp. 150-151

Author(s):

Venita F. Allison ◽

J. E. Ubelaker ◽

J. H. Martin

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Nervous System ◽

Osmic Acid ◽

Sensory Receptors ◽

Transmission Electron ◽

Sensory Structures ◽

Fine Morphology ◽

It has been suggested that parasitism results in a reduction of sensory structures which concomitantly reflects a reduction in the complexity of the nervous system. The present study tests this hypothesis by examining the fine morphology and the distribution of sensory receptors for two species of aspidogastrid trematodes by transmission and scanning electron microscopy. The species chosen are an ectoparasite, Cotylaspis insignis and an endoparasite, Aspidogaster conchicola.Aspidogaster conchicola and Cotylaspis insignis were obtained from natural infections of clams, Anodonta corpulenta and Proptera purpurata. The specimens were fixed for transmission electron microscopy in phosphate buffered paraformaldehyde followed by osmic acid in the same buffer, dehydrated in an ascending series of ethanol solutions and embedded in Epon 812.

Ultrastructure of the soil fungus, Geomyces pannorus

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100113573 ◽

1984 ◽

Vol 42 ◽

pp. 738-739

Author(s):

J. A. Traquair ◽

E. G. Kokko

Keyword(s):

Electron Microscopy ◽

Fine Structure ◽

Low Temperatures ◽

Soil Fungus ◽

Organic Soils ◽

Anatomical Studies ◽

Transmission Electron ◽

Electron Microscopical ◽

With the advent of improved dehydration techniques, scanning electron microscopy has become routine in anatomical studies of fungi. Fine structure of hyphae and spore surfaces has been illustrated for many hyphomycetes, and yet, the ultrastructure of the ubiquitous soil fungus, Geomyces pannorus (Link) Sigler & Carmichael has been neglected. This presentation shows that scanning and transmission electron microscopical data must be correlated in resolving septal structure and conidial release in G. pannorus.Although it is reported to be cellulolytic but not keratinolytic, G. pannorus is found on human skin, animals, birds, mushrooms, dung, roots, and frozen meat in addition to various organic soils. In fact, it readily adapts to growth at low temperatures.