Artifacts on the surface of articular cartilage due to drying methods

1978 ◽  
Vol 36 (2) ◽  
pp. 680-681
Author(s):  
I. Hesse ◽  
W. Hesse
Keyword(s):  
Articular Cartilage ◽  
Critical Point ◽  
Femoral Condyle ◽  
Medial Femoral Condyle ◽  
Drying Methods ◽  
Tissue Preparation ◽  
Critical Point Drying ◽  
Cacodylate Buffer ◽  
Drying Techniques ◽  
Scanning Electron

Since the advent of scanning electron microscopy very contrasting studies on the surface topography of normal and pathological cartilage have been published. The existing literature did not respect the influence of tissue preparation, especially the effect of the drying techniques. Thus the results lead to wrong conclusions. The purpose of this paper is to compare the preservation of the surface morphology obtained from three drying techniques, i. e. air-, freeze- and critical-point drying.Our experiments were performed on normal articular cartilage of 50 sheep, on transplanted cartilage of 45 sheep and on articular cartilage taken intraoperatively from 33 patients. Three adequate samples of articular cartilage attached to bone were dissected out of the weightbearing portion of the medial femoral condyle for air-, freeze- and critical-point drying. They were rinsed in 4 changes of cacodylate buffer (pH=7. 2-7. 4).

Preparation of Articular Cartilage for Scanning Electron Microscopy

1973 ◽  
Vol 31 ◽  
pp. 436-437
Author(s):  
M. L. Zimny ◽  
I. Redler ◽  
J. Fernandez
Keyword(s):  
Articular Cartilage ◽  
Femoral Condyle ◽  
Tissue Preparation ◽  
Electron Microscopic ◽  
Tissue Samples ◽  
Scanning Electron Microscopic ◽  
Electron Microscopic Image ◽  
The Relationship ◽  
Scanning Electron Microscopic Image ◽  
Scanning Electron

The relationship between tissue preparation and a scanning electron microscopic image is still somewhat nebulous. For purposes of answering comments about our observations of articular cartilage, we decided to prepare tissue samples from one area of a femoral condyle, obtained at surgery, in several ways. As a result of this investigation we hoped to find the best way to prepare articular cartilage for maximal visual detail and subsequently standardize our procedures for a comparative study of normal and arthritic cartilage.The samples were fixed as follows: (1) no fixative; (2) 2% glutaraldehyde buffered with cacodylate, pH 7.4; (3) 10% buffered formalin; (4) 0.1% glutaraldehyde in Ringer's; and (5) 1% glutaraldehyde in Ringer's.

scholarly journals Scanning electron microscopy preparation and analysis of the cell cortex ultrastructure

2020 ◽  
Author(s):  
D. Flormann ◽  
M. Schu ◽  
E. Terriac ◽  
M. Koch ◽  
S. Paschke ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Critical Point ◽  
Structural Defects ◽  
Cell Cortex ◽  
Drying Methods ◽  
Actin Network ◽  
Actin Cortex ◽  
Critical Point Drying ◽  
Scanning Electron

AbstractThe cellular cortex is a 200-nm-thick actin network that lies beneath the cell membrane. It is responsible for the mechanical properties of the cell and is involved in many cellular processes, such as cell migration and interactions with the environment. To develop a clear view of the structure of this meshwork, high resolution imaging is essential, such as electron microscopy. This technique requires complex sample preparation that can lead to artifacts like shrinkage or hole formation. We present a preparation method that reduces artifacts significantly. Here, the final drying step that is typically performed by critical point drying is replaced by hexamethyldisilazane drying. We quantitatively investigated sample integrity after both preparation methods, and show that there are significant advantages of hexamethyldisilazane drying compared to critical point drying. Furthermore, automated analysis of a network is classically performed by thresholding-based software programs, which are sensitive to noise and uneven brightness of images. The here presented analysis that we have developed is based on a vectorial node algorithm. It reproduces all kinds of networks sufficiently to allow derivation of quantitative network-specific parameters, such as mesh hole size. We use this analysis to compare the network structure of cells prepared by these two drying methods, and show that hexamethyldisilazane drying leads to fewer artificial mesh holes compared to critical point drying. We thus present here a significantly improved method to quantitatively investigate the actin cortex of cells, and show that hexamethyldisilazane drying leads to more accurate imaging compared to critical point drying.Insight BoxThe highest resolution for imaging the cellular actin cortex is provided by electron microscopy. Scanning electron microscopy samples require a drying process, usually achieved by critical point drying, which is critical for the sample integrity. We compare the structural defects in the actin cortex of hTert RPE1 cells after critical point drying and a chemical based method, namely hexamethyldisilazane drying. In order to characterize the actin network, we also developed a new vectorial based tracing software. We bring here new tool, both experimental and analytical, which will help to streamline studies of the actin cortex.

The Critical Point Drying Method Applied to Scanning Electron Microscopy of L-929 Cells

1970 ◽  
Vol 28 ◽  
pp. 278-279
Author(s):  
Charles TurnbiLL ◽  
Delbert E. Philpott
Keyword(s):  
Electron Microscopy ◽  
Carbon Dioxide ◽  
Surface Tension ◽  
Critical Point ◽  
Freeze Drying ◽  
Attractive Alternative ◽  
Crystal Formation ◽  
Critical Point Drying ◽  
Time Required ◽  
Scanning Electron

The advent of the scanning electron microscope (SCEM) has renewed interest in preparing specimens by avoiding the forces of surface tension. The present method of freeze drying by Boyde and Barger (1969) and Small and Marszalek (1969) does prevent surface tension but ice crystal formation and time required for pumping out the specimen to dryness has discouraged us. We believe an attractive alternative to freeze drying is the critical point method originated by Anderson (1951; for electron microscopy. He avoided surface tension effects during drying by first exchanging the specimen water with alcohol, amy L acetate and then with carbon dioxide. He then selected a specific temperature (36.5°C) and pressure (72 Atm.) at which carbon dioxide would pass from the liquid to the gaseous phase without the effect of surface tension This combination of temperature and, pressure is known as the "critical point" of the Liquid.

The Effects of Drying Techniques on Clay-Rich Soil Texture

1974 ◽  
Vol 32 ◽  
pp. 466-467
Author(s):  
T. G. Naymik
Keyword(s):  
Critical Point ◽  
Liquid Nitrogen ◽  
Liquid Nitrogen Temperature ◽  
Drying Methods ◽  
Air Drying ◽  
Freeze Dried ◽  
Critical Point Drying ◽  
Set Up ◽  
The Relationship ◽  
Quartz Grains

Three techniques were incorporated for drying clay-rich specimens: air-drying, freeze-drying and critical point drying. In air-drying, the specimens were set out for several days to dry or were placed in an oven (80°F) for several hours. The freeze-dried specimens were frozen by immersion in liquid nitrogen or in isopentane at near liquid nitrogen temperature and then were immediately placed in the freeze-dry vacuum chamber. The critical point specimens were molded in agar immediately after sampling. When the agar had set up the dehydration series, water-alcohol-amyl acetate-CO2 was carried out. The objectives were to compare the fabric plasmas (clays and precipitates), fabricskeletons (quartz grains) and the relationship between them for each drying technique. The three drying methods are not only applicable to the study of treated soils, but can be incorporated into all SEM clay soil studies.

Preservation of Plant Cell Surfaces For Scanning Electron Microscopy

1973 ◽  
Vol 31 ◽  
pp. 472-473
Author(s):  
Linda M. Sicko ◽  
Thomas E. Jensen
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Critical Point ◽  
Filter Paper ◽  
Freeze Drying ◽  
Cell Surfaces ◽  
Air Drying ◽  
Popular Method ◽  
Critical Point Drying ◽  
Scanning Electron

The use of critical point drying is rapidly becoming a popular method of preparing biological samples for scanning electron microscopy. The procedure is rapid, and produces consistent results with a variety of samples. The preservation of surface details is much greater than that of air drying, and the procedure is less complicated than that of freeze drying. This paper will present results comparing conventional air-drying of plant specimens to critical point drying, both of fixed and unfixed material. The preservation of delicate structures which are easily damaged in processing and the use of filter paper as a vehicle for drying will be discussed.

Pulmonary microcirculation: tubules rather than sheet and post

1982 ◽  
Vol 53 (2) ◽  
pp. 510-515 ◽  
Author(s):  
W. G. Guntheroth ◽  
D. L. Luchtel ◽  
I. Kawabori
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Critical Point ◽  
Ringer Solution ◽  
Basic Component ◽  
Pulmonary Vasculature ◽  
Critical Point Drying ◽  
Pulmonary Microcirculation ◽  
Scanning Electron

We examined latex casts of the pulmonary microcirculation with the scanning electron microscope (SEM). Mature rats were anesthetized and ventilated; the pulmonary vasculature was washed out with lactated Ringer solution and then filled with a mixture of Geon latexes. The airways were filled with glutaraldehyde with resulting transmural vascular pressures of 10 cmH2O. After critical-point drying and corrosive removal of the lung tissue, SEM studies of the vascular replicas revealed two distinct patterns of pulmonary microcirculation: 1) sparse, long, tubular capillaries that comprise the thin subpleural layer and appear as “filler” in the peribronchial spaces; and 2) alveolar microcirculation that is composed of tightly matted, intersecting tubules, shorter but of the same diameter as type 1, in spherical array in two layers. The alveolar capillaries at low magnification appear superficially as sheets; however, the detailed morphology is not consistent with the sheet-and-post model. We conclude that the basic component of the pulmonary microcirculation is tubular and not different from other capillary beds except in density.

Sign in / Sign up

Export Citation Format

Share Document