scholarly journals Ultrastructure and Glycoconjugate Pattern of the Foot Epithelium of the AbaloneHaliotis tuberculata(Linnaeus, 1758) (Gastropoda, Haliotidae)

2012 ◽  
Vol 2012 ◽  
pp. 1-12 ◽  
Author(s):  
I. Bravo Portela ◽  
V. S. Martinez-Zorzano ◽  
I. Molist- Perez ◽  
P. Molist García
Keyword(s):  
Electron Microscopy ◽  
External Surface ◽  
Light And Electron Microscopy ◽  
Lectin Histochemistry ◽  
Secretory Cells ◽  
High Electron ◽  
Ultrastructural Examination ◽  
Transmission Electron ◽  
Haliotis Tuberculata ◽  
Scanning Electron

The foot epithelium of the gastropodHaliotis tuberculatais studied by light and electron microscopy in order to contribute to the understanding of the anatomy and functional morphology of the mollusks integument. Study of the external surface by scanning electron microscopy reveals that the side foot epithelium is characterized by a microvillus border with a very scant presence of small ciliary tufts, but the sole foot epithelium bears a dense field of long cilia. Ultrastructural examination by transmission electron microscopy of the side epithelial cells shows deeply pigmented cells with high electron-dense granular content which are not observed in the epithelial sole cells. Along the pedal epithelium, seven types of secretory cells are present; furthermore, two types of subepithelial glands are located just in the sole foot. The presence and composition of glycoconjugates in the secretory cells and subepithelial glands are analyzed by conventional and lectin histochemistry. Subepithelial glands contain mainly N-glycoproteins rich in fucose and mannose whereas secretory cells present mostly acidic sulphated glycoconjugates such as glycosaminoglycans and mucins, which are rich in galactose, N-acetyl-galactosamine, and N-acetyl-glucosamine. No sialic acid is present in the foot epithelium.

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

1971 ◽  
Vol 29 ◽  
pp. 410-411 ◽  
Author(s):  
Jane A. Westfall ◽  
S. Yamataka ◽  
Paul D. Enos
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Osmium Tetroxide ◽  
External Surface ◽  
Three Dimensional ◽  
Surface Structures ◽  
Transmission Microscopy ◽  
Transmission Electron ◽  
Freeze Dried ◽  
Scanning Electron

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).

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

1996 ◽  
Vol 74 (5) ◽  
pp. 809-815 ◽  
Author(s):  
G. K. Walker ◽  
C. A. Edwards ◽  
M. G. Black
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Dreissena Polymorpha ◽  
Osmium Tetroxide ◽  
Light And Electron Microscopy ◽  
Comparative Morphology ◽  
Dreissena Bugensis ◽  
Transmission Electron ◽  
Contrast Microscopy ◽  
Scanning Electron

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.

scholarly journals Micromorphology, Ultrastructure and Histochemistry of Commelina benghalensis L. Leaves and Stems

Plants ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 512
Author(s):  
Kareshma Doolabh ◽  
Yougasphree Naidoo ◽  
Yaser Hassan Dewir ◽  
Nasser Al-Suhaibani
Keyword(s):  
Electron Microscopy ◽  
Glandular Trichomes ◽  
Light And Electron Microscopy ◽  
Trichome Density ◽  
Histochemical Analysis ◽  
Leaf Section ◽  
Commelina Benghalensis ◽  
Transmission Electron ◽  
Important Medicinal Plant ◽  
Scanning Electron

Commelina benghalensis L. is used as a traditional medicine in treating numerous ailments and diseases such as infertility in women, conjunctivitis, gonorrhea, and jaundice. This study used light and electron microscopy coupled with histochemistry to investigate the micromorphology, ultrastructure and histochemical properties of C. benghalensis leaves and stems. Stereo and scanning electron microscopy revealed dense non-glandular trichomes on the leaves and stems and trichome density was greater in emergent leaves than in the young and mature. Three morphologically different non-glandular trichomes were observed including simple multicellular, simple bicellular and simple multicellular hooked. The simple bicellular trichomes were less common than the multicellular and hooked. Transmission electron micrographs showed mitochondria, vesicles and vacuoles in the trichome. The leaf section contained chloroplasts with plastoglobuli and starch grains. Histochemical analysis revealed various pharmacologically important compounds such as phenols, alkaloids, proteins and polysaccharides. The micromorphological and ultrastructural investigations suggest that Commelina benghalensis L. is an economically important medicinal plant due to bioactive compounds present in the leaves and stems.

Morphological effects of Epiccocum nigrum and its antibiotic flavipin on Monilinia laxa

1995 ◽  
Vol 73 (3) ◽  
pp. 425-431 ◽  
Author(s):  
Carlos Madrigal ◽  
Paloma Melgarejo
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Light And Electron Microscopy ◽  
Lipid Bodies ◽  
Monilinia Laxa ◽  
Epicoccum Nigrum ◽  
Transmission Electron ◽  
Germ Tubes ◽  
Scanning Electron

The influence of an isolate of Epicoccum nigrum and one of its antibiotics, flavipin, on the spores, mycelium, and germ tubes of Monilinia laxa in culture was studied using light and electron microscopy. Epicoccum nigrum and flavipin induced the development of stromata in cultures. Abundant clusters of microconidia of M. laxa were produced on the induced stromata exposed to E. nigrum and flavipin. Deformation of hyphae and germ tubes such as swellings, coilings, and abnormal ramifications were also noticeable under light and scanning electron microscopy after treatment with E. nigrum or flavipin. Transmission electron microscopy revealed cytoplasmic coagulation of the cells and abundant vacuoles and lipid bodies associated with membranes. In some cases alteration and disorganization of membranes was also apparent. Key words: antagonism, antibiosis, flavipin, biological control.

Ultrastructural Observations on the Ovary and Eggs, and the Development of Egg Adhesion in Pacific Herring (Clupea harengus pallasi)

1990 ◽  
Vol 47 (8) ◽  
pp. 1495-1504 ◽  
Author(s):  
D. J. Gillis ◽  
B. A. McKeown ◽  
D. E. Hay
Keyword(s):  
Electron Microscopy ◽  
External Surface ◽  
Clupea Harengus ◽  
Dense Layer ◽  
Pacific Herring ◽  
Transmission Electron ◽  
Clupea Harengus Pallasi ◽  
Egg Membrane ◽  
Thin Electron ◽  
Scanning Electron

Changes in Pacific herring ovarian tissues and eggs during the four stages, late vitellogenic, ovulating, ovulated, and fertilized, were investigated by transmission and scanning electron microscopy. During the late vitellogenic and transitional stages the egg membranes consisted of five layers: the externus, distal inter-layer, internus, proximal inter-layer, and the sub-internus. The proximal and distal inter-layers do not appear to have been described elsewhere. A class of small, non-vitellogenic oocytes which were observed in late vitellogenic and ovulating ovaries, but not in ovulated ones or spawned eggs, are tentatively described as 'pre-ovulatory atretic oocytes'. Transmission electron microscopy (TEM) results demonstrated a collapse of the pores in the internus which may serve as a mechanical means of achieving egg membrane semipermeability during the first, or ovulation hydration. A thin, electron-dense layer was deposited on the external surface of the externus during ovulation. This epi-layer expanded on contact with seawater and became strongly adhesive. The results of the analyses are discussed in relation to an industrial roe-product quality problem called 'fragile roe' — an expression which describes a condition of reduced adhesion of eggs.

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

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.

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

1978 ◽  
Vol 36 (2) ◽  
pp. 82-83 ◽  
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).

Application of Scanning Electron Microscopy to Medical Research

1969 ◽  
Vol 27 ◽  
pp. 12-13
Author(s):  
J. D. Hutchison
Keyword(s):  
Electron Microscopy ◽  
Electron Microscope ◽  
Medical Research ◽  
Prosthetic Heart Valve ◽  
School Of Medicine ◽  
Transmission Electron ◽  
Definition Of ◽  
Mechanism Of Failure ◽  
The Brain ◽  
Scanning Electron

When the transmission electron microscope was commercially introduced a few years ago, it was heralded as one of the most significant aids to medical research of the century. It continues to occupy that niche; however, the scanning electron microscope is gaining rapidly in relative importance as it fills the gap between conventional optical microscopy and transmission electron microscopy.IBM Boulder is conducting three major programs in cooperation with the Colorado School of Medicine. These are the study of the mechanism of failure of the prosthetic heart valve, the study of the ultrastructure of lung tissue, and the definition of the function of the cilia of the ventricular ependyma of the brain.

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.

Scanning and Transmission Electron Microscopy of Human Red Blood Cells

1969 ◽  
Vol 27 ◽  
pp. 44-45
Author(s):  
A.J. Tousimis ◽  
T.R. Padden
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Blood Cells ◽  
Room Temperature ◽  
Type Specimen ◽  
New Combination ◽  
Human Red Blood Cells ◽  
Transmission Electron ◽  
Microscope Slides ◽  
Scanning Electron

The size, shape and surface morphology of human erythrocytes (RBC) were examined by scanning electron microscopy (SEM), of the fixed material directly and by transmission electron microscopy (TEM) of surface replicas to compare the relative merits of these two observational procedures for this type specimen.A sample of human blood was fixed in glutaraldehyde and washed in distilled water by centrifugation. The washed RBC's were spread on freshly cleaved mica and on aluminum coated microscope slides and then air dried at room temperature. The SEM specimens were rotary coated with 150Å of 60:40- gold:palladium alloy in a vacuum evaporator using a new combination spinning and tilting device. The TEM specimens were preshadowed with platinum and then rotary coated with carbon in the same device. After stripping the RBC-Pt-C composite film, the RBC's were dissolved in 2.5N HNO3 followed by 0.2N NaOH leaving the preshadowed surface replicas showing positive topography.

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