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At least 19 recordsLinked to original sources
PubMed1979

Virus-cell interactions as seen by scanning electron microscopy.

Scanning electron microscopy (SEM) has been used during the past few years to determine surface alterations of cells infected with a variety of RNA and DNA viruses. Infection of different cultured cells by RNA and DNA viruses usually revealed dramatic shape changes with surface alterations. The most frequent changes seen were "rounding up" of cells and the development of surface microprojections such as ruffles and microvilli. In the light of available knowledge, suggestions are made in this review for future SEM studies in this field with more sensitive methodologies, which will enable even better characterization of virus-induced cell surface changes.

Animals↗
PubMed1979

A study of arterial prostheses by scanning electron microscopy.

Scanning electron micrographs were taken of ten different vascular prostheses. The micrographs showed that some prostheses were damaged and some had traces of chemicals on their surface. The application of standard vascular clamps damaged most grafts and some showed remarkable changes on resterilization.

Arteries↗
PubMedDate not supplied

Scanning electron microscopy in the study of lung cancer. New technique of comparative studies on the same lung cancer cells by light microscopy and scanning electron microscopy.

A new technique for observing the same lung cancer cells by light microscope and SEM was developed. By this technique it was clarified that the surface ultrastructures of epidermoid carcinoma, adenocarcinoma and oat-cell carcinoma cells are different from each other. Those of adenocarcinoma and mesothelial cells were quite different. This technique might be of use, adding new information into the ordinary cytologic diagnosis of cancer cells.

Adenocarcinoma↗
PubMed1979

Hormonal influences on the dog prostate--a correlation study with light microscopy, transmission and scanning electron microscopy.

Dog prostates under defined hormonal influences were investigated by light microscopy (LM), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The normal acinar cell apices exhibited well-developed, densely packed microvilli. TEM demonstrated numerous secretory granules, indicating a high secretory activity. Following castration, the acinar cells of the dog prostate showed rounded apices. Most of the microvilli disappeared and only knob-like protrusions were seen. Castrated dogs following administration of 3 alpha-androstandiol showed fewer microvilli than the controls; however, a well-developed undulating surface could be observed. Castrated dogs given 3 alpha-androstandiol and cyproterone acetate showed almost completely atrophic glandular cells. Prostates of dogs with spontaneous benign prostatic hyperplasia (BPH) were characterized by pleomorphism of cell shapes and surfaces. The different hormonal influences induced changes of the prostatic surface structures and secretory activity.

Androstanols↗
PubMedDate not supplied

[Isolation of erythroblastic islands. Study by optical and scanning electron microscopy (author's transl)].

1. A simple technique is described for isolation and estimation of number of erythroblastic islands (EBI) in rat bone marrow. The number of EBI decreases during hypertransfusion polycythemia, and increases during experimentally-induced hemolytic anemia. It has also been possible to maintain EBI in vitro, under culture conditions, for up to 36 hours. 2. Each EBI contains a central cell having the character of a macrophage-histiocyte which adheres to glass and spreads, while still retaining its connections with the erythroblasts. 3. In an EBI the erythroblasts are arranged in the form of concentric rings, with the outer cells being more mature than the inner. The outermost layer is frequently made up of reticulocytes even in the isolated island. The erythroblasts of a single ring appear to be at the same stage of maturation which suggests that they are derived from the same stem cell. 4. Using a coordinate reference system, studies of nuclear expulsion were made, by both optical microscopy and scanning electron microscopy.

Animals↗
PubMed1977

X-ray diffraction and scanning electron microscopy of bovine media aortic wall.

Scanning electron microscopy and high angle X-ray diffraction were used to define the relationship between collagen and elastin of bovine aortic wall. The diffraction pattern shows on one hand that the broad rings at 4.5 A and 9 A, due to elastin, do not orient on stretching and on the other hand, that the collagen rings at 11 A and 2.9 A start to orient at low elongations. These data together with scanning electron microscopy suggest a tight structural relationship between collagen and elastin that should influence the mechanics of deformation at all degrees of elongation.

Animals↗
PubMed1979

An unlabeled antibody macromolecule technique using hemocyanin for the identification of type B and type C retrovirus envelope and cell surface antigens by correlative fluorescence, transmission electron, and scanning electron microscopy.

The present resolution (75-100 A) of the conventional scanning electron microscope (SEM) and its ability to image the surfaces of large numbers of whole cells in situ permit the approach of problems such as viral and cell surface antigen localization by immunological labeling with visual markers. Identification of virus and cell surface antigens in situ has been accomplished in indirect reactions by unconjugated markers. Hemocyanin (Hcy) from whelk, Busycon canniculatum, has been developed as an immunospecific marker for virion and cell surface labeling in the electron microscope. Its size (30 x 50 nm) and distinct cylindrical shape permit easy visualization in the SEM and the transmission electron microscope (TEM). The Hcy method involves the preparation of antisera to Hcy in appropriate hosts for use in an unlabeled antibody macromolecule procedure based exclusively on antigen-antibody affinity to couple the macromolecule to the antigen site. Further correlative data from fluorescence microscopy can be obtained from similarly labeled samples by binding fluorescein to the bridging antibodies used in the Hcy technique. The usefulness of the Hcy marker system was demonstrated by employing highly specific antisera to the major envelope and cell surface glycoprotein (gp70) of Rauscher murine leukemia virus (R-MuLV), a type C retrovirus. The antiserum was shown to bind to the virion and cell surfaces of virus-infected cells in the homologous virus-infected cell system. It also demonstrated the expression of R-MuLV gp70-related antigens on a murine cell line Mm5mt/c1 which produces mouse mammary tumor virus (MuMTV), a type B retrovirus. Furthermore, when used in the Hcy marker system the anti-gp70 serum was able to distinguish type B from type C budding virus on the same cell. Methods for the preparation of immunoreagents and labeling of cells are discussed.

Animals↗
PubMed1979

The influence of the buffer on maintenance of tissue lipid in specimens for scanning electron microscopy.

Preparations of tissues and cells for scanning electron microscopy (SEM) fixed with glutaraldehyde (G CHO) buffered in either Na-cacodylate or Piperazine-N-N' bis (20-ethanol sulfonic acid) (PIPES) differ in their morphology. The influence of the nature of these buffers in the tissue fixing and washing solutions on appearance in scanning electron microscopy is described. Biochemical determinations of lipid retention were performed on frog and chick embryos fixed for 24 hours with 3% G CHO in either 0.03 and 0.1 M PIPES (ph. 7.3) or 0.1 M Na-cacodylate (ph. 7.3). Embryonic tissue was chosen for its relatively high lipid content and delicacy which may be expected to enhance the sensitivity at which buffer effects become apparent. The comparable small and uniform sizes of the embryos minimize differences in fixation quality due to penetration. Lipid, recovered from homogenized tissue after treatment with chloroform/methanol/water (1:2.1:1, v/v) was considered as retained. The extraction results, which showed a significant reduction of lipid losses when PIPES buffer was used, are taken to account for the morphological differences observed in SEM and transmission electron microscopy (TEM).

Animals↗
PubMed1976

T cells, B cells and intermediate forms in the newborn studied by scanning electron microscopy and phosphatase marker.

Scanning electron microscopic studies of peripheral blood lymphocytes showed that percentage of T cells was lower in four cases of premature infants born between 30th and 34th week of gestation when compared with that in four cases of term infants (18.6% and 39.9% counted from 956 and 1,379 lymphocytes, respectively). The occurence of lymphocytes with intermediate patterns of surface morphology (I cells) was noted in both groups studied. Percentages of B and I cells were higher in the premature than in the term infant (26.3% and 55.1% and 20.0% and 39.1%, respectively). Analogous tendency in the T cell occurence in the premature and the term infant was demonstrated with acid phosphatase as T cell marker.

Acid Phosphatase↗
PubMed1977

[Use of a new process of metallic shadowing by cathodic vaporization for scanning electron microscopy of tegumental products of insects].

In scanning electron microscopy, the recent process, not yet much used, of coating subjects with gold by cathodic sputtering, allows one in biology and especially in entomology, to visualize microreliefs, habitually masked, when the old technique called evaporating technique, was used. This process effectively allows one to deposit a very much thinner layer of metal and, because it is performed at room temperature, prevents artifacts caused by the high temperature necessitated by the other technique, whose previous results nevertheless remain generally correct.

Animals↗
PubMed1977

Morphology of human cells, carrier of measles virus, using nomarski optics and scanning electron microscopy.

A human cell line (Lu106) carrier of measles virus was studied in a Nomarski interference-contrast microscope (NICM) and a scanning electron microscope (SEM). The results from this were correlated with fine structure findings obtained from analyses made in the transmission electron microscope (TEM). In both the NICM and SEM it was possible to identify intracellular perinuclear structures, which most likely represent aggregates of measles nucleocapsids. These structures appeared in the NICM as opaque vesicles and in the SEM as bulges in the flattened cells. The SEM also proved to be used for determining cell surface characteristics specific for the carrier culture, which were lacking in uninfected Lu106 cells. In the carrier culture, there were vesiculated cells with bled-like polymorphic and ridged projections, and cells with webbed cytoplasmic extensions. Ridges and transverse striations observed on these cellular protrusions and on microvilli possibly denote oriented viral nucleocapsids at the cell membrane. Furthermore in the carrier cells, the microvilli were more heterogenous in length and diameter and were more frequently branched or fused together when compared to microvilli in uninfected cells. The results are discussed in view of the available information on the appearance of virus-infected or virus-transformed cells in the SEM, also inregard to the various factors, other than virus infection, which play a role in determining the surface features of monolayer cells.

Cell Line↗
PubMed1979

Scanning electron microscopy of the infective eggs of Hydatigera taeniaeformis.

Scanning electron microscopy of the outer surface coat of the infective eggs of Hydatigera taeniaeformis examined at high magnifications revealed the presence of scale-like features. At low magnifications the surface of eggs appeared smooth. Eggs that were fractured showed a thick inner surface layer of ridges and striations. A second layer characterized by a smooth membrane surface presumably the basement membrane was observed beneath the innermost surface layer. When the eggs were treated with 0.02 M of EDTA the outer surface coat became distorted and the emerging hooks of the embryo could be seen. Small, spherical bosses were observed on the surface of some eggs. Other eggs possibly at an earlier stage of development contained pit-like depressions.

Animals↗
PubMed1979

A simplified technique to prepare fungal specimens for scanning electron microscopy.

A simplified technique to prepare fungal specimens for scanning electron microscopy is described and discussed. Fixation in either 6% glutaraldehyde or 2% Os04 (both unbuffered aqueous solutions), yielded good results. The minimum fixation time in OSO4 was 2 h, in glutaraldehyde 4 to 5 h. Chemical dehydration with 2-methoxyethanol or 2,2-dimethoxypropane proved to be useful since it considerably reduced the preparation time. Because of the relatively few changes of reagent solutions during the whole process, the fungal specimens were less disturbed without much loss of material. The preparation technique described has been applied to specimens of various fungal groups with good results.

Fixatives↗
PubMedDate not supplied

Scanning electron microscopy of euthyroid goiter and Graves's disease.

The scanning electron microscopy of 5 euthyroid polynodular goiters and 5 cases of Grave's disease was studied. In the polynodular goiter most of the follicular cells were flattened. Small, coarse, irregular microvilli were noticed. In the Grave's disease cases the follicular cells were columnar, covered with long microvilli. Marked epithelial infoldings were found. Thick bundles of collagen surrounded the follicles, especially in the polynodular goiter.

Adult↗
PubMed1977

Scanning electron microscopy of human female reproductive tract and amniotic fluid cells.

Scanning electron microscopy was used to examine surface ultrastructural characteristics of cells of the epithelium of female reproductive tract, cervical mucus, and amniotic fluid cells. The female epithelium undergoes hormone-dependent cyclical morphological alterations in cell shape, apical microvilli, ciliation, and secretory patterns. The frequency distribution of ciliated cells varies in different parts of the female reproductive tract and different segments of the same organ. In the endocervix, a few ciliated cells are randomly distributed. The density of ciliated cells is variable in several areas of the endometrium. The sparse distribution of ciliated cells in the central portion of the uterine wall may indicate a possible implantation site. According to surface ultrastructure of cells, three segments are noted in the uterotubal junction: cornual endometrium, interstitial tubal epithelium, and transitional area. The vaginal epithelium is made of flat polygonal cells with interdigitating borders and a fine interlacing network of microridges. After the menopause, the microridge pattern and distinct cell borders are lost or severely modified. Two types of fibrous structures can be found in cervical mucus: a) microfibrils that vary in diameter from 500 to 1,500 A and from bundles or networks, and b) long, thick fibers that vary in diameter from 0.5 to 5 micrometer run parallel to each other, and appear to be made up of microfibrils. Amniotic fluid cells, derived from amniotic epithelium and fetal ectoderm, consist of non-nucleated and nucleated cells with extensive microplicae.

Amniotic Fluid↗
PubMed1975

Histochemistry and scanning electron microscopy of tooth integumental material in humans.

Plaque material on human teeth was investigated using histochemical techniques and scanning electron microscopy. A positive reaction for protein, cargohydrate, and lipids was seen around the fissures and in a well-defined band around the sides of the tooth corresponding to the highest contour. These regions are the location of dense aggregates of bacteria as seen with scanning electron microscopy. This study emphasizes the fact that considerable attention should be given to the cleaning of not only the occlusal surfaces but also the highest contour of the tooth.

Adolescent↗
PubMed1978

[Observation of Schistosoma mansoni by scanning electron microscopy].

The integumental surface of adult Schistosoma mansoni was studied by scanning electron microscopy (SEM) at 220 to 10,000 magnifications. SEM shows certain basic features such as spines in the oral sucker and the acetabulum which may facilitate rasping and attachment of the parasite to stay in the bloodstream of the definitive host. It seems likely that SEM visualization will be a means for differentiation some species of the genus Schistosoma.

Animals↗