scholarly journals Contributions of Electron Microscopy to Understand Secretion of Immune Mediators by Human Eosinophils

2010 ◽  
Vol 16 (6) ◽  
pp. 653-660 ◽  
Author(s):  
Rossana C.N. Melo ◽  
Ann M. Dvorak ◽  
Peter F. Weller
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Immune Responses ◽  
Innate Immune System ◽  
Innate Immune ◽  
Cell Secretion ◽  
The Past ◽  
Functional Capabilities ◽  
Immune Mediators ◽  
Transmission Electron

AbstractMechanisms governing secretion of proteins underlie the biologic activities and functions of human eosinophils, leukocytes of the innate immune system, involved in allergic, inflammatory, and immunoregulatory responses. In response to varied stimuli, eosinophils are recruited from the circulation into inflammatory foci, where they modulate immune responses through the release of granule-derived products. Transmission electron microscopy (TEM) is the only technique that can clearly identify and distinguish between different modes of cell secretion. In this review, we highlight the advances in understanding mechanisms of eosinophil secretion, based on TEM findings, that have been made over the past years and that have provided unprecedented insights into the functional capabilities of these cells.

On Future Directions in Pathology

1982 ◽  
Vol 40 ◽  
pp. 274-277
Author(s):  
Benjamin F. Trump ◽  
Irene K. Berezesky ◽  
Raymond T. Jones
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Clinical Pathology ◽  
Future Directions ◽  
Diagnostic Pathology ◽  
The Past ◽  
Transmission Electron ◽  
Organ Systems ◽  
The Many

The role of electron microscopy and associated techniques is assured in diagnostic pathology. At the present time, most of the progress has been made on tissues examined by transmission electron microscopy (TEM) and correlated with light microscopy (LM) and by cytochemistry using both plastic and paraffin-embedded materials. As mentioned elsewhere in this symposium, this has revolutionized many fields of pathology including diagnostic, anatomic and clinical pathology. It began with the kidney; however, it has now been extended to most other organ systems and to tumor diagnosis in general. The results of the past few years tend to indicate the future directions and needs of this expanding field. Now, in addition to routine EM, pathologists have access to the many newly developed methods and instruments mentioned below which should aid considerably not only in diagnostic pathology but in investigative pathology as well.

The Dislocation Patterns in Deformed Metals: Dislocation Densities, Distributions and Related Misorientations

2007 ◽  
Vol 550 ◽  
pp. 193-198
Author(s):  
Edgar F. Rauch ◽  
G. Shigesato
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Transmission Electron Microscopy ◽  
Dislocation Substructure ◽  
Metals And Alloys ◽  
The Past ◽  
Transmission Electron ◽  
Dislocation Densities ◽  
Broad Variety ◽  
The Relationship

The dislocation substructure that appears in deformed metals and alloys have been extensively investigated in the past by transmission electron microscopy (TEM). They are known to form a broad variety of microstructures. These substructures are characterized by three main parameters, namely the density of the dislocations that are trapped in the tangles, their degree of patterning and the misorientation between the cells. The aim of the present work is to investigate the relationship between these features and the mechanical properties of the material.

Polyhydroxyalkanoates production by actinobacteria isolated from soil

2009 ◽  
Vol 55 (7) ◽  
pp. 790-800 ◽  
Author(s):  
Fernanda Matias ◽  
Diego Bonatto ◽  
Gabriel Padilla ◽  
Maria Filomena de Andrade Rodrigues ◽  
João Antonio Pêgas Henriques
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Carbon Source ◽  
Streptomyces Species ◽  
The Past ◽  
Medium Chain Length ◽  
Transmission Electron ◽  
Rhodococcus Species ◽  
Wide Range ◽  
Bacterial Groups

Polyhydroxyalkanoates (PHAs) are biodegradable and renewable polymers produced by a wide range of bacterial groups. New microbial bioprospection approaches have become an important way to find new PHA producers and new synthesized polymers. Over the past years, bacteria belonging to actinomycetes group have become known as PHA producers, such as Nocardia and Rhodococcus species, Kineosphaera limosa Liu et al. 2002, and, more recently, Streptomyces species. In this paper, we disclose that there are more actinobacteria PHA producers in addition to the genera cited. Some unusual genera, such as Streptoalloteichus , and some genera frequently present in soil, such as Streptacidiphilus , have been found. Thirty-four isolates were able to accumulate poly(3-hydroxybutyrate) and a number of these have traces of poly(3-hydroxyvalerate) when cultivated on glucose or glucose and casein as carbon source. Furthermore, some strains showed traces of medium chain length PHA. Transmission electron microscopy demonstrated that the PHA accumulation occurs in hyphae and spores.

Electron microscopy of alpha-plutonium

1986 ◽  
Vol 44 ◽  
pp. 564-565
Author(s):  
K. P. Staudhammer ◽  
K. A. Johnson ◽  
M. Stevens ◽  
W. J. Medina
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
World Wide ◽  
The Past ◽  
Thin Foils ◽  
Transmission Electron ◽  
Solid Phases ◽  
Primary Problem

During the past several decades metallurgists world-wide have sought for a reliable and reasonable method to characterize plutonium and its alloys via transmission electron microscopy. Metallurgically, plutonium (Pu) represents one of the most fascinating metals; it has six solid phases and contracts when melted.A number of workers over the years have tried to produce thin foils of plutonium, but the foils were later shown to have been completely converted to oxide. The primary problem has been in the preparation of electron transparent thin foils of a material having one of the highest atomic numbers that is highly oxidation prone, in addition to being radioactive. Advances in Pu metallography in the late 70's and early 80's produced a new series of electro-chemical thinning solutions modified for plutonium.

scholarly journals Identification of Sample Preparation Artifacts in Powder Analysis

2001 ◽  
Vol 9 (2) ◽  
pp. 30-32
Author(s):  
Andreas Taubert
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Inorganic Materials ◽  
Particle Nucleation ◽  
X Ray Diffraction ◽  
X Ray ◽  
The Past ◽  
Transmission Electron ◽  
Powder Analysis ◽  
Particle Shapes

The synthesis of inorganic materials of a specific size and shape is a key aspect in modern powder technology. During the past two decades, solution-based precipitation reactions have been explored for controlled particle formation. A wide variety of particle shapes, sizes, and compositions has been demonstrated. However, several questions, especially concerning particle nucleation, remain. Some of these questions are currently addressed by investigating precipitate (ex situ) at different reaction stages by means of powder x-ray diffraction (PXRD), scanning (SEM) and transmission electron microscopy (TEM).

a Dislocation Loops in MgO

1977 ◽  
Vol 35 ◽  
pp. 306-307
Author(s):  
J. Narayan ◽  
S. M. Ohr
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Thermal Breakdown ◽  
Dislocation Loops ◽  
Electron Micrograph ◽  
Burgers Vector ◽  
Electron Microscope Investigation ◽  
Long Period ◽  
The Past ◽  
Transmission Electron

Dislocation loops having a/2 <110> Burgers vectors on {110} planes introduced by plastic deformation and subsequent annealing of MgO have been studied extensively in the past using transmission electron microscopy.1 Recently it was reported that high temperature electrical conduction for a long period of time (> 100 hours) induced a thermal breakdown2 in MgO crystals. Transmission electron microscope investigation of these samples just before the thermal breakdown, revealed the presence of a type of loop not previously observed in this material with a<100> Burgers vector lying in {100} planes.Figure la-d shows electron micrograph of two of these a<100> type loops for diffraction vectors (ḡ) [200], [020], [220] and [220], These micrographs were taken under kinematical diffraction conditions with the deviation parameter w ∽ 1.0. From stereo microscopy it was determined that the loops labeled α and β lie on (001) and (100) planes respectively.

Morphofunctional state of the peripheral nervous system at the imaginal stage of infection of sheep with fascioliasis

2020 ◽  
Vol 1 (12) ◽  
pp. 22-28
Author(s):  
G. R. Shakirova ◽  
◽  
V. N. Baymatov ◽  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Nervous System ◽  
Peripheral Nervous System ◽  
Structural Changes ◽  
Barrier Properties ◽  
Infected Sheep ◽  
Loose Connective Tissue ◽  
Functional Capabilities ◽  
Transmission Electron

The aim was to compare the features of the structure of the peripheral nervous system in healthy and experimentally infected sheep with fascioliasis on day 142 of the experiment using lightoptical methods, transmission electron microscopy and morphometry. In animals with fascioliasis, destructive changes were found in all the studied structures of the peripheral nervous system. The observed structural changes reduce the functional capabilities of neurons, worsen the trophic and barrier properties of ganglia due to the destruction of blood vessels, extracellular matrix of loose connective tissue, and perineurium.

Preparation of Transmission Electron Microscopy specimens of integrated circuits usinga modified tripod polisher

1994 ◽  
Vol 52 ◽  
pp. 872-873
Author(s):  
Howard Shishido ◽  
David Su
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Integrated Circuits ◽  
Integrated Circuit ◽  
Specific Area ◽  
Specimen Preparation ◽  
Critical Dimensions ◽  
The Past ◽  
Transmission Electron ◽  
Short Period

With the continuous decrease in the critical dimensions of integrated circuit (IC) devices, transmission electron microscopy (TEM) has become an important tool for the study of these devices. Two reasons account for the new emphasis in TEM - small fabrication imperfections that did not affect the performance of devices in the past can no longer be ignored and thus need to be addressed, the dimensions of some features, such as gate oxide thicknesses, have become so small that only TEM can be used reliably to study them. However, as the need for TEM increases, the requirements for specimen preparation also has become more stringent. No longer is it acceptable to blindly prepare samples of blanket films or of any one of an array of devices, the ability to "hit" a specific area in a very short period of time has become a necessity. Fortunately, recent advances in the preparation of TEM specimens of IC devices has relieved some of the pressure of performing these jobs.

Techniques for Transmission Electron Microscopy of Fiber-Matrix Interfaces in Aluminum Alloy-Boron Composites by Ion Erosio

1971 ◽  
Vol 29 ◽  
pp. 204-205
Author(s):  
G. G. Shaw
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Aluminum Alloy ◽  
Electron Beam ◽  
Pure Aluminum ◽  
Ion Milling ◽  
Transmission Electron ◽  
Fiber Matrix ◽  
Ion Erosion ◽  
Row Of Fibers

The morphology and composition of the fiber-matrix interface can best be studied by transmission electron microscopy and electron diffraction. For some composites satisfactory samples can be prepared by electropolishing. For others such as aluminum alloy-boron composites ion erosion is necessary.When one wishes to examine a specimen with the electron beam perpendicular to the fiber, preparation is as follows: A 1/8 in. disk is cut from the sample with a cylindrical tool by spark machining. Thin slices, 5 mils thick, containing one row of fibers, are then, spark-machined from the disk. After spark machining, the slice is carefully polished with diamond paste until the row of fibers is exposed on each side, as shown in Figure 1.In the case where examination is desired with the electron beam parallel to the fiber, preparation is as follows: Experimental composites are usually 50 mils or less in thickness so an auxiliary holder is necessary during ion milling and for easy transfer to the electron microscope. This holder is pure aluminum sheet, 3 mils thick.

Direct Observation of Heat Exchanger Deposits by Cross Sectioning

1967 ◽  
Vol 25 ◽  
pp. 364-365
Author(s):  
R. W. Anderson ◽  
D. L. Senecal
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Heat Exchanger ◽  
Direct Observation ◽  
Cross Sections ◽  
Preparation Method ◽  
Specimen Preparation ◽  
Flowing Water ◽  
Transmission Electron ◽  
Deposit Layer

A problem was presented to observe the packing densities of deposits of sub-micron corrosion product particles. The deposits were 5-100 mils thick and had formed on the inside surfaces of 3/8 inch diameter Zircaloy-2 heat exchanger tubes. The particles were iron oxides deposited from flowing water and consequently were only weakly bonded. Particular care was required during handling to preserve the original formations of the deposits. The specimen preparation method described below allowed direct observation of cross sections of the deposit layers by transmission electron microscopy.The specimens were short sections of the tubes (about 3 inches long) that were carefully cut from the systems. The insides of the tube sections were first coated with a thin layer of a fluid epoxy resin by dipping. This coating served to impregnate the deposit layer as well as to protect the layer if subsequent handling were required.

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