bluuebunny/crossref_metadata_2025 huggingface dataset:
Herpes Simplex Virus Hepatitis in a Healthy Human Adult: Light and Electron Microscopic Features
Authors: Kraft W.J. , Rabin E.R. , Davis G.L. , Gale A.H. , Little J.R. , Reed C.
Published: June 2020

A 25 year old white female developed herpes vaginitis with subsequent dissemination of the virus to the liver. The purpose of the present report is to describe the light and electron microscopic characteristics of herpes simplex hepatitis in a liver biopsy obtained during the patient's hospitalization. Herpes simplex virus was isolated in cell culture from the liver biopsy and skin vesicle during life and from the liver at autopsy. Although we have no direct evidence for underlying immunodeficiency, two of the patient's siblings died at about 1 year of age with apparent infectious diseases, one with varicella and the other with infantile diarrhea. The patient had a normal childhood course of infectious diseases; she was otherwise healthy until dissemination of herpesvirus from the vaginal infection. There was no evidence at autopsy of an underlying disease.
An Immunoelectron Microscopic Study of Type C Virus Particles in Feline Sarcoma Virus-Induced Rat Tumors
Authors: Maruyama K. , Miller M. F. , Wagner S. H. , Dmochowski L.
Published: June 2020

Many type C RNA tumor viruses can infect cells of different species. Following cross-species infection, these viruses are known to exhibit some altered properties. In an attempt to investigate host influence on properties of mammalian RNA tumor viruses, neonatal Wistar rats were inoculated with feline sarcoma virus of Snyder-Theilen strain. A transplantable tumor line designated as RT-FeSV was established from one of these induced tumors. Some syngeneic rats inoculated with RT-FeSV tumors which were passaged in rats less than 3 times developed precipitable serum antibodies to feline leukemia virus (FeLV).
Comparative Morphology of Three Strains of Rabies Virions Propagated in the Reptilian Cell Line, VSW
Authors: Lunger Philip D. , Clark H. Fred
Published: June 2020

Cell line VSW, derived from the spleen of a tumor-bearing Asian pit viper, spontaneously produces C-type virions budding from membranes, and similar virions that develop within mitochondria. Rabies virus has been determined to replicate more efficiently in VSW cells than in a variety of other cell types cultivated from reptiles, amphibians or fish. We have compared the morphology of three strains (CVS, ERA and HEP) of fixed BHK/21 cell-adapted rabies virus in VSW cells infected at a cell multiplicity of infection of 20 and incubated at 33&C for 8 days prior to fixation.
The Four Faces of CHO
Authors: Enlander Derek , Scott Thea , Tobey Robert A.
Published: June 2020

Interphase was originally considered a passive stage in the cell cycle. It is now known to be a time of growth and biochemical activity, consisting of three distinct periods: the initial growth (G1) period; the synthetic (S) period during which the actual replication or doubling of the DNA takes place; the second growth (G2) period. The biochemical events that take place during these three periods are essential for the cell to enter the mitotic(M) period.
Neural Fold Fusion in Xenopus Laevis Embryos
Authors: Mak Linda L.
Published: June 2020

A morphological study of neural fold fusion in neurulae of the African Clawed Toad Xenopus laevis was undertaken. Segments of neural folds were dissected from embryos at Nieuwkoop and Faber stages 18 (neural groove), 19 (neural fold fusion) and 20 (neural tube) and fixed for electron microscopy.

Cells from specimens in the prefusion stage exhibited much vesicular activity, especially those lining the neural groove. In certain instances the vesicles were open, extruding organelles and cytoplasm into the neural groove. The membranous projections of these opened vesicles protruded into the extraembryonic space. Vesicles (v, Fig. 1) were arranged in rows below the surfaces of cells lying along the neural groove. Some vesicles appeared to coalesce to form larger ones.
Microsurgical Studies on the Formation of the Golgi Apparatus and Nuclear Envelope in Amebae
Authors: Flickinger C. J.
Published: June 2020

The means of formation of the Golgi apparatus is uncertain. In beginning these studies, it seemed that an important first step was to determine the degree of dependence of the Golgi apparatus on the nucleus. This was investigated in Amoeba proteus because these cells are readily enucleated microsurgically. Normal amebae contained multiple Golgi bodies, which declined in size and number in the absence of the nucleus, indicating that the Golgi apparatus in amebae depends upon the nucleus. The influence of the nucleus on the Golgi apparatus may be mediated through nuclear RNA synthesis and cytoplasmic protein synthesis, since the ultrastructural effects of enucleation were mimicked by treating amebae with actinomycin D to inhibit RNA synthesis and, in part, by treating cells with emetine, which inhibits protein synthesis in amebae.
Fine Structural Localization of Choline Acetylase at the Neuromuscular Junction
Authors: Barrnett Russell J.
Published: June 2020

During the past several years we have investigated a variety of acyI transferases by combining biochemical, cytochemical and electron microscopic techniques. In each case biochemical justification of each of the cytochemical steps was established prior to the application of cytochemistry to electron microscopy to indicate fine structural localization of the enzymatic activity. Among the enzymes studied have been carnitine acetyl transferase, the mono glyceride pathway of synthesis of triglycerides and the alpha-glycerophosphate pathway of phospholipid synthesis in the absorptive cells of the small intestine as well as the alpha-glycerophosphate pathway of synthesis of phospholipid in hepatic cells. Pathways for the synthesis of phospholipids were also used to study several examples of membrane biogenesis.
The Interpretation of Electron Diffraction Patterns of Faulted Structures
Authors: Cowley J. M.
Published: June 2020

In many high resolution electron micrographs of oxides, minerals and other materials, planar faults, often nearly parallel to the electron beam, are visible. When the crystal structure is clearly resolved the nature of the faults may be evident from the images, as in the case of the faults in the periodicities of the block structures of niobium and niobium-titanium oxides (Iijima, 1973; Iijima, Kimura and Goto, 1973), the shear planes (Wadsley defects) occuring in reduced tungsten trioxide (Iijima, in preparation) and the micro-twins occuring in the mineral enstatite (Iijima and Buseck, in preparation).
Resolution Limits Imposed by Specimen-Electron Interactions
Authors: Beck V. , Crewe A. V.
Published: June 2020

In many respects a scanning microscope is like a television tube; both use a beam of electrons focused to a small spot and scanned in a raster to make a picture. The resolution of the television tube is simply the size of the spot appearing on the tube face. Because there are many ways of measuring the size of an arbitrary intensity distribution, it is difficult to give one number which adequately describes the quality of the image. In order to more precisely characterize the quality of television tubes, Schade used the modulation transfer function (MTF)J The MTF is defined as the ratio of the image spatial frequency distribution to the object spatial frequency distribution. One can easily determine the MTF for a television tube in the following way. To display a delta function on a television tube, one would direct the beam to one point on the screen.
An Experimental Study of Deviations from the Linear Transfer Function
Authors: Voter William A. , Erickson Harold P.
Published: June 2020

In a previous experimental study of image formation using a thin (20 nm) negatively stained catalase crystal, it was found that a linear or first order theory of image formation would explain almost entirely the changes in the Fourier transform of the image as a function of defocus. In this case it was concluded that the image is a valid picture of the object density. For thicker, higher contrast objects the first order theory may not be valid. Second order effects could generate false diffraction spots which would lead to spurious and artifactual image details. These second order effects would appear as deviations of the diffraction spot amplitudes from the first order theory. Small deviations were in fact noted in the study of the thin crystals, but there was insufficient data for a quantitative analysis.
Mini-Scanning Electron Miscroscope Concept
Authors: Evins Donald J. , Engle Robert J.
Published: June 2020

The scanning electron microscope has already established itself as one of the most useful instrument developments in recent years. The SEM provides 20 times greater useful magnifications and up to 500 times greater depth of-field than the best optical microscopes. Until the introduction of the Mini-SEM concept, the cost and complexity of SEM's has limited their use primarily to large research oriented laboratories.

Design features, specifications, and operational characteristics will be reviewed. The Mini-Rapid Scan with resolution of 750Å will be described, along with the Mini-SEM with resolution of 150 to 200Å. Both of these are table top scanning electron microscopes. Various specimen stage options will be illustrated. Other accessories extending the SEM's versatility will be described, such as the energy dispersive x-ray system
Development of 100 kV Field Emission Scanning Electron Microscope
Authors: Koike H. , Harada Y. , Goto T. , Y.Kokubo  , Yamada K. , Someya T. , M.Watanabe
Published: June 2020

During the past ten years, the resolution of the CTEM has been improved to a theoretical value determined by spherical and diffraction aberrations. In the scanning electron microscope, however, the resolution is restricted by the signal-to-noise ratio. Crewe et al were the first to increase the resolution by applying a field emission source to a 35 kV scanning electron microscope, resulting in a 5 Å resolution. Owing to its prominent brightness, the feild emission electron gun promises to increase not only the resolution of STEM images, but also to realize an analytical electron microscope which identifies chemical elements, crystalline structures and chemical bonding in specimen microareas in the order of less than 100 Å.
A High Resolution Dual Gun Electron Miscroscope for TEM and SEM
Authors: Ong P. S. , Gold C. L.
Published: June 2020

Transmission electron microscopes (TEM) have the capability of producing an electron spot (probe) with a diameter equal to its resolving power. Inclusion of the required scanning system and the appropriate detectors would therefore easily convert such an instrument into a high resolution scanning electron microscope (SEM). Such an instrument becomes increasingly useful in the transmission mode of operation since it allows the use of samples which are considered too thick for conventional TEM. SEM accessories now available are all based on the use of the prefield of the objective lens to focus the beam. The lens is operated either as a symmetrical Ruska lens or its asymmetrical version. In these approaches, the condensor system of the microscope forms part of the reducing optics and the final spot size is usually larger than 20Å.
A New Image Processing Technique for STEM
Authors: Kokubo Yasushi , Koike Hirotami , Someya Teruo
Published: June 2020

One of the advantages of scanning electron microscopy is the capability for processing the image contrast, i.e., the image processing technique. Crewe et al were the first to apply this technique to a field emission scanning microscope and show images of individual atoms. They obtained a contrast which depended exclusively on the atomic numbers of specimen elements (Zcontrast), by displaying the images treated with the intensity ratio of elastically scattered to inelastically scattered electrons. The elastic scattering electrons were extracted by a solid detector and inelastic scattering electrons by an energy analyzer. We noted, however, that there is a possibility of the same contrast being obtained only by using an annular-type solid detector consisting of multiple concentric detector elements.
Scanning Transmission Energy Analyzing Microscope (“STEAM”)
Authors: Horner Jack A.
Published: June 2020

The use of electron energy loss analyzers has been rather extensive in recent years. Most analyzers have been designed to discriminate losses in the range 0 < ΔE < 100eV or to reject the inelastically scattered component of transmitted beams for the purpose of contrast and resolution enhancement. More recent interest has been directed towards detection of energy losses associated with inner shell ionizations, simultaneous with characteristic X-ray emission. Such an apparatus has been under development in this laboratory for the past 2½ years. The design and use of this device for elemental analysis in thin sections is described.
S. E. M. Observations of Limestone Pore Space Replicas
Authors: Becher J. W.
Published: June 2020

Pore geometry in carbonate rocks is of interest to petroleum geologists because it reflects the complex diagenetic changes that may create or destroy porosity. The size distribution of pore throats (restrictions in the continuous maze of pore channels) is a major parameter controlling hydrocarbon migration through water-wet rocks.

Pore space replicas (plastic casts of pore space with the mineral material removed) have decided advantages over actual rock material for pore space observations. The replication of a limestone with 10 percent porosity will yield a plastic replica with 90 percent porosity.
The Application of the Scanning Electron Microscope—Microprobe System in the Construction of Paragenetic Sequences
Authors: Klasik John A.
Published: June 2020

In the geological sciences a paragenetic sequence may be defined as the ordering of diagenetic steps a rock or sediment has undergone since its deposition. For numerous years this analysis of relationships between sediment constituents and binding agents has been evaluated by means of the light microscope and thin sections. This method is quite valuable for sediment coarser than medium silt (40 microns). Material finer than this must be dealt with in bulk. This present study utilizes the SEM-Microprobe system to construct a paragenetic sequence for a Middle Eocene chert collected from the Central Pacific by the Deep Sea Drilling Project.
Microstructure of Oxidized Silicon Nitride
Authors: Tighe Nancy
Published: June 2020

Hot-pressed silicon nitride, Si3N4, is a candidate material for gas turbine components. Service temperatures in these engines are as high as 1400°C and it is necessary therefore to consider the effect of oxidation on the components' lifetime. Strength of reaction sintered silicon nitride increased slightly after oxidation at 1000°C to 1200°C and it was considered therefore that the oxide layer, which was identified as cristobalite by X-ray diffraction, was protective. The present electron microscopic investigations were made to determine the oxide microstructure and the nature of the oxide-silicon nitride interface.
TEM of Pyrolytic Al2O3 and Ta-Al2O3 Thin Films on Silicon
Authors: Anderson R. M.
Published: June 2020

Pyrolytically deposited Al2O3, thin films are employed as dielectrics in metal-insulator-semiconductor structures used for insulated-gate field-effect transistors. Ideally, very thin Al2O3 films should have smooth surfaces, uniform cross-sections and high electrical resistivity. These requirements are best met by amorphous Al2O3, film microstructures. Pyrolysis of amorphous Al2O3 films must be undertaken at temperatures lower than 700°C with a concomitant low deposition rate. The incorporation of Ta in the Al2O3 yields amorphous structures at deposition tempera tures of about 800-900°C with substantially higher deposition rates.
Electron Beam Induced Thermal Effects in Amorphous Se64As16Au20 Thin Films
Authors: Mee P. B.
Published: June 2020

It is the purpose of this paper to describe some preliminary observations on the thermal stability of Se64As16Au20 alloy thin films and to relate crystallization, melting, vaporization, etc., to the input electron beam flux and estimated maximum temperature rise. Thin films were produced from 80:20 arsenic modified selenium glass and gold for this study. Co-deposition was carried out on 600Å thick carbon films (at 25°C) supported on 200 mesh copper electron microscope grids(≈10−6 Torr)
Effect of Shock Loading on the Microstructure of Uniloy 326
Authors: Staudhammer K. P. , Murr L. E.
Published: June 2020

The effect of shock loading on a variety of steels has been reviewed recently by Leslie. It is generally observed that significant changes in microstructure and microhardness are produced by explosive shock deformation. While the effect of shock loading on austenitic, ferritic, martensitic, and pearlitic structures has been investigated, there have been no systematic studies of the shock-loading of microduplex structures.

In the current investigation, the shock-loading response of millrolled and heat-treated Uniloy 326 (thickness 60 mil) having a residual grain size of 1 to 2μ before shock loading was studied. Uniloy 326 is a two phase (microduplex) alloy consisting of 30% austenite (γ) in a ferrite (α) matrix; with the composition.3% Ti, 1% Mn, .6% Si,.05% C, 6% Ni, 26% Cr, balance Fe.
Observations of the Microstructure of WC-Co Cemented Carbides
Authors: Kimmel E. R. , Scheithauer W.
Published: June 2020

Cemented carbides (hard metals) of the WC-Co type generally consist of two phases: WC, the major phase, and a Co-rich binder phase. The two alloys studied in this investigation were WC-6w/OCo and WC-13w/OCo. In production of these alloys, a ball milled mixture of WC powder and Co powder is die compacted and subsequently sintered at about 1400°C. This condition constitutes liquid phase sintering and results in a fully densified material.

The work was undertaken to determine the feasibility of studying microstructures of hard metals using thin foils prepared by ion-beam thinning. Attempts at producing thin foils by electrolytic thinning have met with limited success due to non uniform thinning of the two phases. In contrast, we found that ion-beam thinning easily produced thin foils having relatively large and uniformly thin areas.
Quantitative Analysis of Asbestos Minerals in Air and Water
Authors: Chatfield E. J.
Published: June 2020

The effects of inhalation of asbestos particles are well known. However, although the significance of asbestos particles when ingested is not fully understood, there is some evidence of increased incidence of gastrointestinal carcinoma where individuals have been exposed to the material over a long period. Methods are therefore required by which trace concentrations of asbestos minerals in both air and ingestibles can be monitored.
Pollutant Identification by Selected Area Electron Diffraction. II. The Limitations
Authors: Ferrell R. E. , Paulson G. G. , Walker C. W.
Published: June 2020

Single crystal electron diffraction patterns can be interpreted in a fairly straightforward manner because with a little knowledge of crystallography one can predict the kind of image to be formed by certain minerals. Close agreement between observed and theoretical patterns identifies the particles. However, in practice, electron diffraction patterns can be rather ambiguous or difficult to unravel. Most of the errors are inherent characteristics of certain samples and cannot be corrected easily. The most common of these are the subject of this discussion.
Comparative Microstructures of Ion Milled and Electrochemically Thinned Composite Materials
Authors: Russell R.R.
Published: June 2020

Transmission electron microscopy of metallic/intermetallic composite materials is most challenging since the microscopist typically has great difficulty preparing specimens with uniform electron thin areas in adjacent phases. The application of ion milling for thinning foils from such materials has been quite effective. Although composite specimens prepared by ion milling have yielded much microstructural information, this technique has some inherent drawbacks such as the possible generation of ion damage near sample surfaces.
Inhibition of Viral Glycoprotein Transport in MDCK Cells
Authors: Alonso F. V. , Roth M. G. , Melsen L. R. , Srinivas R. V. , Compans R. W.
Published: June 2020

Our laboratory has been investigating the cellular pathways involved in the transport of viral giycoproteins to distinct membrane domains in the MDCK line of canine kidney cells. These cells form junctional complexes which divide the plasma membrane into two domains: the apical surface from which influenza (Figs, la & lb) and parainfluenza viruses bud and the basolateral membrane where assembly of vesicular stomatitis virus (VSV) (Figs. 2a & 2b) and retroviruses take place. Our previous results on virusinfected MDCK cells include the following: (1) Although the site of virus maturation is probably determined by the site of membrane insertion of viral giycoproteins, the information for the directional transport of giycoproteins resides in the polypeptide backbone, and not in the carbohydrate portion, since polarized maturation is maintained even under conditions where glycosylation is completely blocked by tunicamycin, an inhibitor of asparagine-linked oligosaccharide biosynthesis. (2) In doubly-infected cells, polarized maturation of viruses at opposite membranes is observed, indicating that the sorting mechanisms responsible for directing the giycoproteins of VSV and influenza virus to separate surface domains continue to operate. (3) No correlation can be made between the viral maturation site and the presence or absence of sialic acid in viral giycoproteins, since influenza C virions, which contain sialic acid, bud at the apical surface like influenza A virus, which lacks this terminal sugar.
Hepatocyte Alterations in Guinea Pigs FED Polychlorinated Biphenyls (PCBs), Dibenzodioxins (PCDD), AND DIBENZOFURANS (PCDF)
Authors: Turner J. N. , Collins D. N.
Published: June 2020

A fire involving an electric service transformer and its cooling fluid, a mixture of PCBs and chlorinated benzenes, contaminated an office building with a fine soot. Chemical analysis showed PCDDs and PCDFs including the highly toxic tetra isomers. Guinea pigs were chosen as an experimental animal to test the soot's toxicity because of their sensitivity to these compounds, and the liver was examined because it is a target organ. The soot was suspended in 0.75% methyl cellulose and administered in a single dose by gavage at levels of 1,10,100, and 500mgm soot/kgm body weight. Each dose group was composed of 6 males and 6 females. Control groups included 12 (6 male, 6 female) animals fed activated carbon in methyl cellulose, 6 males fed methyl cellulose, and 16 males and 10 females untreated. The guinea pigs were sacrificed at 42 days by suffocation in CO2. Liver samples were immediately immersed and minced in 2% gluteraldehyde in cacadylate buffer at pH 7.4 and 4°C. After overnight fixation, samples were postfixed in 1% OsO4 in cacodylate for 1 hr at room temperature, embedded in epon, sectioned and stained with uranyl acetate and lead citrate.
Difference Fourier Analysis of Glucose Embedded and Frozen Hydrated Purple Membrane
Authors: Jaffe Jules S. , Glaeser Robert M.
Published: June 2020

Although difference Fourier techniques are standard in X-ray crystallography it has only been very recently that electron crystallographers have been able to take advantage of this method. We have combined a high resolution data set for frozen glucose embedded Purple Membrane (PM) with a data set collected from PM prepared in the frozen hydrated state in order to visualize any differences in structure due to the different methods of preparation. The increased contrast between protein-ice versus protein-glucose may prove to be an advantage of the frozen hydrated technique for visualizing those parts of bacteriorhodopsin that are embedded in glucose. In addition, surface groups of the protein may be disordered in glucose and ordered in the frozen state. The sensitivity of the difference Fourier technique to small changes in structure provides an ideal method for testing this hypothesis.
Electron Microscopy of Unstained, Hydrated Protein Crystal at 4 K
Authors: Jeng T.W. , Chiu W. , Brakmo L. , Müller K.H. , Knapek E. , Stemmer A. , Zeitler E
Published: June 2020

Electron radiation damage is the most fundamental problem in studying biological specimen at high resolution. Knapek and Dubochet have reported a factor of 30-300 in reducing the damage of small organic crystals at 4 K compared to 300 K. Chiu and co-workers have made a preliminary report that there was a factor of 10 in reducing the damage of structural details between 4 to 6 Å in a hydrated, unstained protein crystal with the Munich superconducting lens microscope. This paper presents our current data on the damage study of glucose embedded crotoxin complex with the Berlin superconducting lens microscope operated at 100 keV and our preliminary result on imaging this protein crystal to 9.5 Å resolution in a medium dose condition.
Isolation of the Crystalline Arrays from the Yeast Plasma Membrane
Authors: Sosinsky Gina , Glaeser Robert M.
Published: June 2020

Crystalline arrays of particles found in freeze-fracture replicas of the yeast plasma membrane have been used extensively as a test specimen for investigating artifacts that can occur during the freeze fracture process. No information has yet been obtained about the particles themselves from electron microscopic techniques other than freeze fracture. The current model of the paracrystals consists of three intramembranous particles arranged in a hexagonal lattice: 1) a large 100 K particle on the PF, which has a “volcano” appearance in replicas that are uncontaminated by water vapor, 2) a smaller EF particle at the threefold axis of the hexagonal lattice, and 3) an even smaller EF particle which fits into the crater of the PF volcano particle. We have now isolated the crystalline arrays of the yeast plasma membrane for further structural studies by freeze fracture, surface replication, and negative staining, in order to test this current model.
Cation Transport and the Initiation of Mel Cell Differentiation
Authors: Levenson R. , Housman D.
Published: June 2020

The murine erythroleukemia (MEL) cell system has served as an important in vitro model for the process of erythroid differentiation for the past decade. Under a controlled set of experimental conditions, MEL cells can be induced to undergo a program of terminal erythroid differentiation which closely resembles the process of normal murine erythropoiesis. MEL cells were originally derived from the spleens of mice infected with Friend virus complex. These virally transformed cells can be grown indefinitely by serial passage in tissue culture medium, but become committed to undergo a program of terminal erythroid differentiation when challenged with dimethylsuIfoxide (DMSO) or a wide variety of other agents.
Electron and Immunoelectron Microscopical Studies on the Extracellular Protease (Keratinase) of Dermatophytes
Authors: Sei Y. , Takiuchi I. , Masutani M.
Published: June 2020

Dermatophytes, known to contain the proteolytic enzyme keratinase can grow in keratinized structures. Here we describe the digestion of the horny layer and the first localization of the enzyme by immunoelectronmicroscopy. Microsporum canis isolated from an outpatient was cultured in a medium of: human hair, 2.9g; glucose, 0.5g; MgSO4-7H2O, 0.06 g; thiamine 0.01g; pyridoxine 0.01 g; and inositol 0.05 g in one liter of 0.028 M phosphate buffer (pH 7.8). The enzyme was isolated from the medium and purified by chromatography. Human skin was incubated with the purified protease (2mg/ml) for 12 hrs at 37° C, and then processed for electron microscopy. Controls were incubated without enzyme. Using rabbit IgG antibody against the purified enzyme the IgG-Fab'-peroxidase complex was synthesized according to the method of Nakane and Kawaoi. That complex gave a single band in double immunodiffusion against purified protease and in immunoelectrophoresis at pH 4.0 and 9.3. Human hairs with fungi were removed from the keratin medium on the 12th day, fixed with periodate-lysin-paraformaldehyde for 24 hrs at 4°C. They were again washed in PBS, preincubated in 3,3'-diaminobenzidine (DAB) for 30 min at room temp., put in a Graham and Karnovsky medium containing DAB and H2 O2 as a substrate for 5 min at room temp., postfixed in 1% OSO4 in PBS for 1 hr at 4°C., and embedded in Epon.
Biological Acoustic Microscopy - Living Cells at 37°C and Fixed Cells in Cryogenic Liquids
Authors: Hildebrand J.A. , Rugar D. , Quate C.F.
Published: June 2020

The scanning reflection acoustic microscope uses high frequency sound to create images with sub-micron resolution. A single-element sapphire lens focuses sound to a diffraction-limited spot in a liquid coupling medium. With the object placed near the focus, the spot of sound is mechanically scanned while the magnitude of the acoustic reflection is recorded for each point on the object. The resulting acoustic image is bright in areas of large acoustic reflection and dark in areas of small acoustic reflection. Acoustic images of biological cells contain information on cellular viscous, elastic and topographic properties. This paper presents acoustic images of living and fixed chick heart fibroblasts grown on glass substrates.
Ultrastructural Features of Leydig Cell Hyperplasia Due to an hCG-Producing Testicular Tumor
Authors: Asa S. L. , Bayley T. A. , Horvath E. , Kovacs K.
Published: June 2020

Leydig cell clusters in the adult human testis are known to enlarge during chronic stimulation with excess LH as in Klinefelter's syndrome or following administration of exogenous human chorionic gonadotropin (hCG). However, the ultrastructural features of this hyperplasia, to our knowledge, have not been reported in association with testicular neoplasms producing hCG.

We report the case of a 21-year-old man who sought medical attention because of gynecomastia. Laboratory investigation revealed a marked increase in serum hCG and elevated a-fetoprotein. A testicular mass was palpable on examination and the patient underwent orchiectomy.
Selective Destruction of Mitochondria by Aziridinylbenzoquinone (AZQ)
Authors: Greenwood M.A. , Smith B.H. , Cooke C. , Robinson A. , Komblith P.L. , Cummins C.
Published: June 2020

Aziridinylbenzoquinone (AZQ or 2, 4-diaziridinyl-3, 6-bis-carboethoxyamino-1, 4-benzoquinone, NSC No. 182986) is a new chemotherapy agent characterized by lipid solubility, high cerebrospinal fluid penetrance and potential as an antiglioma agent.

In our laboratory the effects of AZO on 20 human central nervous system glioma-derived tumor cell lines in culture have been studied utilizing both in vitro solid phase and aqueous microcytotoxicity assays. In these in vitro assays a test concentration range over 3 log units (0.1 to 100 μg/ml AZQ) has indicated varying sensitivity of glioma-derived tumor cell lines. Concentrations sufficient to produce greater than 30 percent cytotoxicity ranged from 1.0 yg/ml to 50 yg/ml, being different for each tumor line tested.
A Scanning Electron Microscopic Study on the Initial Invasion of Ehrlich Ascites (EA) Tumor Cells in Peritoneal Layer
Authors: Chew E.C. , Ooi E.C.V. , Lam O.W. , Kwan S.M.
Published: June 2020

Several investigators have reported the invasive processes of tumor cells on the exposed basement membrane or injured peritoneum, however the detail of how the tumor cells adhere to the mesothelium and basement membrane has not been demonstrated. The present communication reveals the detailed process of the adhesion of EA tumor cells in the peritoneal layer by scanning electron microscopy.
Granular Cell Tumor (Myoblastoma) of RAT Brain
Authors: White Yvonne , Sheldon Winslow , Hoage Terrell , West Robert
Published: June 2020

Granular cell myoblastoma is a rare tumor of which the nature and origin has been controversial. The cytogenesis of this tumor has been suggested as a neoplastic derivation from adult or embryonic muscle tissue, a histiocytic storage phenomenon, of neural origin and as a neoplasm derived from Schwann cells.

This report presents the ultrastructure of a spontaneously occurring granular cell tumor from the brain of a 22 month old female Sprague- Dawley rat. Gross examination revealed an oval, gray external mass 3x4 mm in size and located on the cerebellar dorsal surface. This tumor was connected by a narrow stalk to a tumor mass located in the molecular layer of the cerebellum. The external tumor and the stalk were excised for electron microscopy (EM) and the remaining tumor mass, brain, and stalk were processed for light microscopy (LM).
Characterization of Prostatic Epithelial Cells in Organotypic Culture
Authors: Terracio Louis , Douglas William H.J.
Published: June 2020

Cell cultures of prostatic epithelial tissue provide a model allowing the study of a single factor on prostatic epithelium without the complicating influences of the stroma. Investigators have developed methods of establishing prostatic epithelium in monolayer culture that maintain good differentiated structure and function, however, even these systems do not maintain the histological organization or columnar polarity of the epithelial cells and thus leave something to be desired. Work by Moscona and Douglas et al., have shown that epithelial cells cultured on a 3-dimensional collagen sponge matrix (GELFOAM, UPJOHN CO.) are capable of reaggregating to form histological structures similar to those found in the intact organ (e.g. alveolar-like structures in the lung, thus they are called organotypic cultures). Engle jat ell., have shown that this superior morphology is also reflected in an increased response of these cells to hormones ini vitro and thus reflects an increase in the retention of differentiated function.
Ruthenium Red Staining of Human Hard Keratin Fibers
Authors: Buhrer M. C. , Mathews R. A.
Published: June 2020

Ruthenium red has been used as a stain to demonstrate a variety of extracellular materials, especially acid mucopolysaccharides. It also reacts with certain intracellular and extracellular lipids. Since biochemical studies in our laboratory demonstrated the presence of a variety of monosaccharides in human hair ruthenium red staining procedures were adopted in order to evaluate the presence and morphological location of acid oligosaccharides in the keratinized aspect of hair.
Selective Contrasting of Cell Surface Material inAllogromia Sp. with Alcian Blue
Authors: Bowser Samuel S.
Published: June 2020

Bidirectional transport of 1μm latex particles occurs on the outer reticulopodial surfaces ofAllogromia. We are currently studying the ultrastructure of the pseudopodial surface in d e tail to help formulate models which explain the observed activities of particles. Thin sections prepared by conventional methods showed, essentially, a featureless surface. Studies of shadowed whole mounts suggested the presence of cell coat and substrate-associated material. Therefore, we sought to o b tain selective contrasting of cell coat material in sectioned specimens. Alcian blue/glutaraldehyde fixation visualizes cell coat material successfully on both reticulopods and cell body surface below the theca. New features of the theca have also been identified.
Morphogenesis of the Murine Mammary Tumor Virus in Cells Treated with Inhibitors of Protein Glycosylation
Authors: Sarkar Nurul H.
Published: June 2020

Tunicamycin (TM) and 2-deoxyglucose (2-DG) have been shown to inhibit the glycosylation of the polypeptides of many enveloped viruses, including retroviruses. The production of the two retroviruses that have been studied to date, the murine leukemia and Rous sarcoma viruses, is significantly inhibited by TM and 2-DG. Moreover, the viruses that are released from the treated cells lack their envelope glycoproteins and are noninfectious. In order to determine if TM and 2-DG have a similar effect on the murine mammary tumor virus (MuMTV) we examined the morphogenesis of MuMTV in TM and 2-DG treated and non-treated MuMTV producing tissue culture cells.
Electron Microscopic Detection and Characterization of Nonhuman Primate Enteric Viruses
Authors: Smith G. C. , Heberling R. L. , Kalter S. S.
Published: June 2020

A number of viral agents are recognized as and suspected of causing the clinical condition “gastroenteritis.” In our attempts to establish an animal model for studies of this entity, we have been examining the nonhuman primate to ascertain what viruses may be found in the intestinal tract of “normal” animals as well as animals with diarrhea. Several virus types including coronavirus, adenovirus, herpesvirus, and picornavirus (Table I) were detected in our colony; however, rotavirus, astrovirus, and calicivirus have not yet been observed. Fecal specimens were prepared for electron microscopy by procedures reported previously.
Qualitative and Quantitative Characteristics of Rat Aortic Intimal Response to Endothelial Cell Injury
Authors: Visscher G. E. , Robison R. L. , Billings C. W.
Published: June 2020

It was our goal to characterize, qualitatively and quantitatively, the changes associated with arterial intimal proliferation after endothelial cell injury in rats. The work which is presented here was performed to establish semi-automated morphometric methods and baseline data for this animal model upon which further experiments could be based.
Use of Protein a Conjugated to Peroxidase to Localize Immunoglobulin G in SSPE Ferret Brain
Authors: Brown Hannah R. , Nostro Anthony F. , Thormar Halldor
Published: June 2020

Subacute sclerosing panencephalitis (SSPE) is a slowly progressing disease of the CNS in children which is caused by measles virus. Ferrets immunized with measles virus prior to inoculation with the cell associated, syncytiogenic D.R. strain of SSPE virus exhibit characteristics very similar to the human disease. Measles virus nucleocapsids are present, high measles antibody titers are found in the sera and inflammatory lesions are prominent in the brains. Measles virus specific immunoglobulin G (IgG) is present in the brain,and IgG/ albumin ratios indicate that the antibodies are synthesized within the CNS.
Clusters: The New Markers
Authors: Hainfeld J. F. , Wall J. S.
Published: June 2020

For several years high resolution STEMS have easily visualized single heavy atoms. Attempts to mark biomolecules by covalently linking reactive heavy atom compounds have not been totally successful due to: 1) high dose - 100-3000 electrons/Å2 are necessary to see a single heavy atom, causing much damage to the biomolecule, 2) atom motion - beam energy is high enough to break bonds and form ions, thus allowing the atoms to hop away from their native positions, 3) background heavy atoms confuse the interpretation, 4) single heavy atoms on top of a protein mass have reduced contrast and are often not clearly visible. Although image enhancement procedures and averaging of periodic structures may help, some of the above problems usually remain.
Paracrystalline Arrays of Horse Spleen Ferritin
Authors: Massover William H.
Published: June 2020

Each molecule of the major iron-storage protein, ferritin, has a well-known architecture, with a 24-subunit protein shell (d=130 Å) surrounding a central cavity (d=75Å) that can be filled with a variable amount of mineralized ferric iron. By manipulating the salt composition and amount, horse spleen ferritin can be induced to form large cubic or tetragonal crystals usable for structure analysis by x-ray diffraction. Despite the success of the x-ray diffraction approach, further procedures must be developed for use with structural studies of the many ferritins that resist ready crystallization (i.e., those from neoplastic cells). Ultrastructural analysis of biomacromolecules is greatly facilitated if they can be prepared in the form of thin crystalline or paracrystal l ine layers (e.g., 2). Although ferritin mixed with certain lipids has been shown to organize into ordered planar arrays, there have been no reports about the preparation and electron microscope study of thin microcrystals of this metalloprotein. The present report describes our initial results with electron microscopy of ordered thin arrays of horse spleen ferritin.
Correlative Electron, Ion and Laser microprobe Analysis of Particle-Laden Alveolar Macrophages
Authors: Linton R. W. , Shelburne J. D. , Simons D. S. , Ingram P.
Published: June 2020

The use of microanalytical techniques for the subcellular localization of chemical components, both physiologic and xenobiotic, is indicated to better characterize the pathophysiology of alveolar macrophage (AM) interactions with respirable particles. This study correlates conventional SEM/energy dispersive X-ray microanalysis (EDX) with ion microprobe (Cameca IMS-3f) and laser microprobe (Leybold-Heraeus LAMMA 500) mass spectrometry of AMs.
Laser Annealing - Crystal Growth at High Velocities
Authors: Poate J. M.
Published: June 2020

There has been remarkable interest over the past five years in the laser annealing of semiconductors. The initial Russian and Italian studies showed that ion implantation damage in semiconductors could be removed by pulsed or continuous wave laser irradiation and the term laser annealing was coined. It is now generically applied to a much broader class of phenomena ranging from crystal growth to alloying. Lasers and other directed energy sources, such as electron or even ion beams, offer the possibility of heating the surface layers of solids in a unique spatial and temporal fashion. For example, surface layers can be melted and solidified in times as shgrt as nanoseconds. These resolidified layers are typically 1000A thick and most structural analysis has come from Rutherford backscattering and channeling, and transmission electron microscopy techniques.
Electron Diffraction Analysis of Microtwin Structures in Regrown (III) Silicon
Authors: Ling P. , Gronsky R. , Washburn J.
Published: June 2020

The defect microstructures of Si arising from ion implantation and subsequent regrowth for a (111) substrate have been found to be dominated by microtwins. Figure 1(a) is a typical diffraction pattern of annealed ion-implanted (111) Si showing two groups of extra diffraction spots; one at positions (m, n integers), the other at adjacent positions between <000> and <220>. The object of the present paper is to show that these extra reflections are a direct consequence of the microtwins in the material.
Formation of Persistent Slip Band in Fatigued Copper Single Crystals
Authors: Jin N. Y.
Published: June 2020

Localised plastic deformation in Persistent Slip Bands(PSBs) is a characteristic feature of fatigue in many materials. The dislocation structure in the PSBs contains regularly spaced dislocation dipole walls occupying a volume fraction of around 10%. The remainder of the specimen, the inactive "matrix", contains dislocation veins at a volume fraction of 50% or more. Walls and veins are both separated by regions in which the dislocation density is lower by some orders of magnitude. Since the PSBs offer favorable sites for the initiation of fatigue cracks, the formation of the PSB wall structure is of great interest. Winter has proposed that PSBs form as the result of a transformation of the matrix structure to a regular wall structure, and that the instability occurs among the broad dipoles near the center of a vein rather than in the hard shell surounding the vein as argued by Kulmann-Wilsdorf.
Tem Studies of Dislocations Generated at Crack Tips
Authors: Horton J. A. , Ohr S. M.
Published: June 2020

Observations of the dislocation structure near the tips of propagating cracks are important in understanding metal fracture. Past TEM observations have shown screw dislocation pileups emitted from Mode I.II cracks. Dislocation theory has been applied to explain these observed pileups. From this analysis, fracture mechanics parameters such as stress intensity factors have been calculated.
Microstructures in Explosively Consolidated Molybdenum Powder: A Tem Study
Authors: Murr L.E.
Published: June 2020

Dynamic compaction of metal and alloy powders has been recognized as a technique capable of producing consolidated materials possessing unique mechanical properties. In the present work molybdenum powder has been consolidated by explosives to produce a residual hardness which exceeds that of conventionally processed molybdenum bars by 55 percent, and unsintered molybdenum powder extrusions by 45 percent. This high hardness has been observed only in shock-loaded molybdenum sheet. A comparison of the microstructures in explosively consolidated molybdenum powder and shockloaded molybdenum sheet materials shows a very clear distinction between them. This is illustrated in Fig. 1(a) and (b). Figure 1(a) shows the asconsolidated molybdenum powder material to be characterized by fine subgrains having an average boundary misorientation of 6°. Dark patches of dislocation tangles also occupy many of the subgrains.
Secondary Fluorescence Corrections in thin Film Microanalysis
Authors: Bourdillon A. J.
Published: June 2020

Though secondary fluorescence corrections in thin film analysis are generally negligible, there are instances where they are needed. These include cases of certain dilute species in certain matrices, and the measurement of foil thickness by K/L emission ratios of given species which depend on absorption processes.
Loss of Coherency of Precipitates in Al-Si: An Hvem Study
Authors: Westmacott K. H. , Dahmen U.
Published: June 2020

Recent studies have shown that lattice defects often play an indispensable role in precipitation reactions. For many plate-shaped precipitates the incorporation of a vacancy loop in the habit plane facilitates formation of the new phase. In some cases the precipitates nucleate semi coherently when vacancies and solute atoms coprecipitate (e.g. P t-C); in others the initially coherent precipitates acquire vacancies and lose coherency later in the precipitation sequence (e.g. Al-Cu).
Interfacial Reactions of Nickel and Cobalt thin Films on Silicon
Authors: Chena L.J. , Hou C.Y. , Chang T.T.
Published: June 2020

The interactions of metal thin films with silicon has been of great interest for its practical applications as means of forming metal silicide contacts in microelectronic industry. Nickel and cobalt thin films on silicon share many important similarities. Firstly, both Ni and Co are transition metals. Secondly, both Ni and Co atoms are found to be dominant moving species during thin film reactions. Thirdly, the formation of silicides follows the sequence of Ni2 (Co2 )Si, Ni(Co)Si and Ni(Co)Si2 with increasing annealing temperatures. Fourthly, both Nisi2 and CoSi2 have a CaF2 structure with small lattice mismatch (< 1.1 %) with silicon and are known to grow epitaxially on low index planes of Si. In this study, we report the results of our study on the factors influencing the formation and growth of nickel and cobalt silicides on silicon.
Catalyst Studies Under Reactor-Realistic Conditions
Authors: Nicholls R. D. , Nicholson E. D. , Toran J. R. , Kelley M. J.
Published: June 2020

The use of controlled atmosphere stages to study chemically sensitive specimens such as catalysts is well established and has been recently reviewed. The effectiveness of CAEM cells for catalyst studies is limited by the difference between their pressure and flow rate regime versus that of chemical reactors, and their lack of analytical spectroscopy. To meet this need, we have modified a commercial TEM (Philips EM-400) by addition of specially constructed accessories.