A Simple Method to Estimate the Number of Autophagic Elements by Electron Microscopic Morphometry in Real Cellular Dimensions

Autophagic elements typically appear as spherical bodies. During their life they undergo a series of changes (e.g., fusion, degradation of content, and swelling) which influence their size in a way that may be characteristic for cell type, stage of maturation, or various experimentally manipulated parameters. A simple and time efficient method is suggested here to use exactly calculated specific surface values and estimate average diameter and number of autophagic elements in real cellular dimensions. The method is based on the easiest morphometric determination of relative surface (surface density) and volume (volume density) data by electron microscopy. A series of data from real experimental samples of liver and exocrine pancreatic cells are offered to illustrate the potential of these measurements and calculations.

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Light microscopic morphometric analysis of peroxisomes by automatic image analysis: advantages of immunostaining over the alkaline DAB method.

Journal of Histochemistry & Cytochemistry ◽

10.1177/40.1.1370307 ◽

1992 ◽

Vol 40 (1) ◽

pp. 115-121 ◽

Cited By ~ 20

Author(s):

K Beier

Keyword(s):

Image Analysis ◽

Light Microscopy ◽

Morphometric Analysis ◽

Protein A ◽

Volume Density ◽

Section Thickness ◽

Automatic Image Analysis ◽

Electron Microscopic ◽

Lr White ◽

Electron Microscopic Morphometry

The feasibility of light microscopic post-embedding immunocytochemistry for morphometry of peroxisomes using automatic image analysis was investigated and compared with the classical alkaline DAB method. Perfusion-fixed rat liver tissue was either embedded in LR White or incubated in the alkaline diaminobenzidine (DAB) medium for cytochemical visualization of catalase. Sections from the LR White-embedded material were incubated with a monospecific antibody against catalase, followed by protein A-gold and silver intensification. Determination of peroxisomal volume density in sections of different thickness revealed that the values increased with section thickness in DAB-stained sections but were unaffected in immunostained preparations. Moreover, the absolute value for volume density of peroxisomes, as determined by light microscopy in immunostained sections, was quite close to the value obtained by analysis of electron microscopic preparations. Finally, morphometric analysis of bezafibrate-induced peroxisome proliferation revealed that the ratio of proliferation obtained by light microscopy in immunostained sections was very close to the results obtained by electron microscopic morphometry. The main advantage of post-embedding immunostaining for light microscopic morphometry is that it restricts the immunocytochemical reaction product to the surface of the section, thus making it independent of section thickness.

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Ultrastructural changes in rat hepatocytes after partial hepatectomy, and comparison with biochemical results

Journal of Cell Science ◽

10.1242/jcs.50.1.433 ◽

1981 ◽

Vol 50 (1) ◽

pp. 433-448

Author(s):

A.B. Murray ◽

W. Strecker ◽

S. Silz

Keyword(s):

Partial Hepatectomy ◽

Specific Effect ◽

Rat Hepatocytes ◽

Volume Density ◽

Ultrastructural Changes ◽

Sham Operation ◽

Electron Microscopic ◽

Electron Microscopic Morphometry ◽

Mitochondrial Volume ◽

Massive Accumulation

Ultrastructural changes in rat hepatocytes in the first 24 h following partial hepatectomy (p.h.), i.e. in the premitotic phase of liver regeneration, were studied using electron microscopic morphometry. Livers were investigated 1/2, 1, 4, 8, 12, 20 and 24 h after p.h. and 1/2, 8, 20 and 24 h after a sham operation. Two effects appear to be associated specifically with the regeneration process: (1) an increase in the volume density of lysosomes to a peak between 4 and 8 h after p.h.; and (2) a doubling in the number of mitochondria per cell by 24 h without any associated increase in the total mitochondrial volume. Two further changes were observed only after p.h.: (1) a massive accumulation of lipid in the form of lipid droplets by 24 h; and (2) the appearance of ‘protein droplets’ (very large lysosomal-like structures) at various stages. Both these changes appear to be secondary effects associated with the stimulation for, but not necessary to, cell division. The loss of glycogen observed immediately after both p.h. and a sham operation is a non-specific effect probably resulting from operation-induced stress. The results are discussed with reference to the changes observed in the biochemical composition of blood plasma. Glucagon appears to play an important role in the stimulation of some of the ultrastructural changes observed.

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Content of intramyocellular lipids derived by electron microscopy, biochemical assays, and 1H-MR spectroscopy

Journal of Applied Physiology ◽

10.1152/japplphysiol.01174.2001 ◽

2002 ◽

Vol 92 (6) ◽

pp. 2264-2272 ◽

Cited By ~ 81

Author(s):

Hans Howald ◽

Chris Boesch ◽

Roland Kreis ◽

Sibylle Matter ◽

Rudolf Billeter ◽

...

Keyword(s):

Resonance Spectroscopy ◽

Strongly Correlated ◽

Intramyocellular Lipid ◽

Intramyocellular Lipids ◽

Electron Microscopic ◽

1H Mr Spectroscopy ◽

Biochemical Assays ◽

Electron Microscopic Morphometry ◽

Invasive Techniques

Three different methods to determine intramyocellular lipid (IMCL) contents in human skeletal muscle have been compared. 1H-magnetic resonance spectroscopy (MRS) was evaluated against electron microscopic morphometry and biochemical assays of biopsy samples from m. tibialis anterior of 10 healthy subjects. The results of 1H-MRS and morphometry were strongly correlated, proving the validity of the1H-MRS results for the noninvasive determination of IMCL. Biochemical assays yielded results that did not significantly correlate with the results of the other methods. When IMCL levels obtained from the three methods are expressed in common units, it was found that1H-MRS yielded IMCL average levels that were 1.8 times lower than those found by morphometry. Potential reasons for the discrepancy are discussed. It is expected that 1H-MRS will be suitable to replace invasive techniques for IMCL determination, whenever noninvasiveness is crucial, e.g., for repeated investigations in studies of substrate recruitment and recovery in exercise.

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A light and electron microscopic study of the structure of the nucleus preopticus and nucleus lateral tuberis of the goldfish, Carassius auratus

Canadian Journal of Zoology ◽

10.1139/z76-165 ◽

1976 ◽

Vol 54 (9) ◽

pp. 1423-1437 ◽

Cited By ~ 18

Author(s):

R. E. Peter ◽

Y. Nagahama

Keyword(s):

Third Ventricle ◽

Average Diameter ◽

Large Cell ◽

Cell Types ◽

Type Ii ◽

Cell Type ◽

Electron Microscopic ◽

Type Iii ◽

Goldfish Carassius Auratus ◽

Nucleus Lateral Tuberis

On the basis of fine structure only one cell type could be identified in the nucleus preopticus. The nucleus lateral tuberis (NLT) contains three distinct cell types. Cell type 1, primarily in the NLT pars lateralis, is a large cell with many dense-core granules (DCG) 97.3 nm average diameter. Cell type II, primarily in the NLT pars anterioris, is smaller and contains few DCG, averaging 70.9 nm. Cell type III, found in the NLT pars posterioris, pars inferioris and posteriorly in the pars anterioris, is a small cell with DCG similar to type II cells. Cell type III additionally has large irregular granular bodies (dimensions up to 2 μm) that stain with aldehyde fuchsin and are visible with the light microscope. The possible role of the various cell types in controlling pituitary function is discussed.The juxta-ventricular border of the ependyma in the NPO and NLT regions is lined with cilia and microvilli, each with a regionalized distribution. In addition, there are cells with bleblike cytoplasmic extensions into the third ventricle in the ependyma layer in the NLT pars anterioris and pars posterions regions.

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Transmission Electron Microscopy of Protein Macromolecules

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100066176 ◽

1971 ◽

Vol 29 ◽

pp. 424-425

Author(s):

Henry S. Slayter

Keyword(s):

Biological Systems ◽

Metal Vapor ◽

Resolving Power ◽

Electron Microscopic ◽

Chemical Methods ◽

Molecular Weights ◽

The Past ◽

Physical Chemical ◽

Transmission Electron

Electron microscopic methods have been applied increasingly during the past fifteen years, to problems in structural molecular biology. Used in conjunction with physical chemical methods and/or Fourier methods of analysis, they constitute powerful tools for determining sizes, shapes and modes of aggregation of biopolymers with molecular weights greater than 50, 000. However, the application of the e.m. to the determination of very fine structure approaching the limit of instrumental resolving power in biological systems has not been productive, due to various difficulties such as the destructive effects of dehydration, damage to the specimen by the electron beam, and lack of adequate and specific contrast. One of the most satisfactory methods for contrasting individual macromolecules involves the deposition of heavy metal vapor upon the specimen. We have investigated this process, and present here what we believe to be the more important considerations for optimizing it. Results of the application of these methods to several biological systems including muscle proteins, fibrinogen, ribosomes and chromatin will be discussed.

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Dendritic cells of the human epidermis: immuno-electron microscopic studies of la antigen reactivity

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100084090 ◽

1978 ◽

Vol 36 (2) ◽

pp. 644-645

Author(s):

G. Rowden ◽

M. G. Lewis ◽

T. M. Phillips

Keyword(s):

Dendritic Cells ◽

Langerhans Cells ◽

Cell Types ◽

Cell Type ◽

Electron Microscopic ◽

La Antigen ◽

Microscopic Studies ◽

A Cell ◽

C3 Receptors ◽

Antigen Reactivity

Langerhans cells of mammalian stratified squamous epithelial have proven to be an enigma since their discovery in 1868. These dendritic suprabasal cells have been considered as related to melanocytes either as effete cells, or as post divisional products. Although grafting experiments seemed to demonstrate the independence of the cell types, much confusion still exists. The presence in the epidermis of a cell type with morphological features seemingly shared by melanocytes and Langerhans cells has been especially troublesome. This so called "indeterminate", or " -dendritic cell" lacks both Langerhans cells granules and melanosomes, yet it is clearly not a keratinocyte. Suggestions have been made that it is related to either Langerhans cells or melanocyte. Recent studies have unequivocally demonstrated that Langerhans cells are independent cells with immune function. They display Fc and C3 receptors on their surface as well as la (immune region associated) antigens.

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Determination of the phase structure of polymerblends by electron microscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100109604 ◽

1978 ◽

Vol 36 (1) ◽

pp. 492-493

Author(s):

Dr. G. Kaemof

Keyword(s):

Screw Extruder ◽

Electron Microscopic ◽

Thin Sections ◽

Single Screw Extruder ◽

Transmission Electron ◽

The Matrix ◽

Twin Screw ◽

Special Case ◽

Microscopic Investigations

A mixture of polycarbonate (PC) and styrene-acrylonitrile-copolymer (SAN) represents a very good example for the efficiency of electron microscopic investigations concerning the determination of optimum production procedures for high grade product properties.The following parameters have been varied:components of charge (PC : SAN 50 : 50, 60 : 40, 70 : 30), kind of compounding machine (single screw extruder, twin screw extruder, discontinuous kneader), mass-temperature (lowest and highest possible temperature).The transmission electron microscopic investigations (TEM) were carried out on ultra thin sections, the PC-phase of which was selectively etched by triethylamine.The phase transition (matrix to disperse phase) does not occur - as might be expected - at a PC to SAN ratio of 50 : 50, but at a ratio of 65 : 35. Our results show that the matrix is preferably formed by the components with the lower melting viscosity (in this special case SAN), even at concentrations of less than 50 %.

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Trial production of γ-type energy filtering TEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100139391 ◽

1995 ◽

Vol 53 ◽

pp. 604-605

Author(s):

Y. Taniguchi ◽

E. Nakazawa ◽

S. Taya

Keyword(s):

Magnetic Energy ◽

Electron Optics ◽

Electron Microscopic ◽

Mass Spectrometers ◽

Ion Optics ◽

Energy Filtering ◽

New Information ◽

New Type ◽

Fringing Fields

Imaging energy filters can add new information to electron microscopic images with respect to energy-axis, so-called electron spectroscopic imaging (ESI). Recently, many good results have been reported using this imaging technique. ESI also allows high-contrast observation of unstained biological samples, becoming a trend of the field of morphology. We manufactured a new type of energy filter as a trial production. This energy filter consists of two magnets, and we call γ-filter since the trajectory of electrons shows ‘γ’-shape inside the filter. We evaluated the new energyγ-filter TEM with the γ-filter.Figure 1 shows schematic view of the electron optics of the γ-type energy filter. For the determination of the electron-optics of the γ-type energy filter, we used the TRIO (Third Order Ion Optics) program which has been developed for the design of high resolution mass spectrometers. The TRIO takes the extended fringing fields (EFF) into consideration. EFF makes it difficult to design magnetic energy filters with magnetic sector fields.

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Polarity Determination in Sphalerite and Wurtzite Structures

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100136106 ◽

1990 ◽

Vol 48 (2) ◽

pp. 500-501

Author(s):

Stuart McKernan ◽

C. Barry Carter

Keyword(s):

Opposite Polarity ◽

Single Domain ◽

Polar Material ◽

Electron Microscopic ◽

Dynamical Interaction ◽

X Ray ◽

Polarity Determination ◽

The Absolute ◽

Microscopic Techniques

The determination of the absolute polarity of a polar material is often crucial to the understanding of the defects which occur in such materials. Several methods exist by which this determination may be performed. In bulk, single-domain specimens, macroscopic techniques may be used, such as the different etching behavior, using the appropriate etchant, of surfaces with opposite polarity. X-ray measurements under conditions where Friedel’s law (which means that the intensity of reflections from planes of opposite polarity are indistinguishable) breaks down can also be used to determine the absolute polarity of bulk, single-domain specimens. On the microscopic scale, and particularly where antiphase boundaries (APBs), which separate regions of opposite polarity exist, electron microscopic techniques must be employed. Two techniques are commonly practised; the first [1], involves the dynamical interaction of hoLz lines which interfere constructively or destructively with the zero order reflection, depending on the crystal polarity. The crystal polarity can therefore be directly deduced from the relative intensity of these interactions.

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