Tissue sectioning comparison

Fluorescence Microscope. A useful light microscope utilizes UV light to induce fluorescence in microscopic samples (40). Because fluorescence is often the result of trace components in a given sample rather than intrinsic fluorescence of the principal component, it is useful in the crime laboratory for the comparison of particles and fibers from suspect and crime scene. Particles of the same substance from different sources almost certainly show a different group of trace elements. It is also very useful in biology where fluorescent compounds can be absorbed on (and therefore locate and identify) components of a tissue section. 

First, a limited study was performed using breast cancer tissue to establish an optimal protocol of DNA extraction for a-CGH analysis that would allow comparison of a-CGH results after boiling in different solutions three pH values of 7, 9, and 12 of Britton and Robinson buffer solution, and a 0.1 M sodium hydroxide solution. DNA samples extracted from frozen and from FFPE tissue sections by a nonheating protocol were employed, and the results were compared a protocol of boiling samples in 0.1 M sodium hydroxide gave optimal results. 

TABLE 3.1 Comparison of CGH Scores of DNA Samples Extracted from FFPE Tissue Sections between Heating and without Heating Protocols... 

The accuracy of a-CGFI array generated from DNA samples extracted from FFPE tissue sections using our heat-induced retrieval protocol was shown by careful comparison of three groups of samples as indicated by Figure 3.3 and Table 3.1. 

In conclusion, the data described demonstrate the reproducible quality of DNA samples extracted by using a heat-induced retrieval protocol from FFPE tissue sections, based on careful comparison of a-CGH analysis data. This simple and effective DNA extraction protocol may provide an alternative technique for DNA analysis for CGH as well as for other methods of DNA... 

Figure 21.7 Comparison of mass spectra obtained from rat brain. Optical observation of microspotted tissue sections employing spray-droplet (a), droplet (b), and spraycoating (c) methods. Scale bar, 1.0 mm. White squares (a-c) represent the cortex (A, d) and the medulla (B, e) of the cerebellum region, respectively. Accumulated mass spectra collected from each region are shown (d, e). In each spectrum, asterisks represent major unique signals for spectra using the spray-droplet method. The number of detected signals in the mass range of 2000 < m/z < 30,000 from each region is shown (f). Reprinted with permission from Sugiura et al.7...

In many studies it is desirable to gain information from both LM and EM. Methods have been devised for such correlative studies (30-32). Sawada and Esaki s method (33) was designed to address factors that they believed to be important for accurate comparison. These factors are the transparency and thinness of embedded blocks, the flatness of tissue sections, and ease of removal of embedding molds from polymerized Epon blocks. Sawada and Esaki s method is summarized below. 

Compounds that fluoresce under ultraviolet light can be visualized in the tissue sections and their locations recorded with color film. Whole-body tissue sections can be used for histochemical localizations for comparison with the autoradiograms. Furthermore, the areas can be removed, extracted, and the extract chromotographed to identify the chemical nature of the radioactivity revealed by the autoradiogram. 

Autoradiography offered an alternative technique. The earliest experiments followed the uptake of radioiodine into the thyroid by placing the tissue sections in direct contact with photographic plates (Hamilton, Soley, and Eichom, 1940 Leblond, 1943). Belanger and Leblond introduced the use of liquid emulsion in 1946. Initially this was painted onto sections mounted on microscope slides. Later, slides were dipped into liquid emulsion (Joftes and Warren, 1955) or wrapped around with stripping film (Doniach and Pelc, 1950). Semiquantitative comparisons... 

Long, A. A., Komminoth, P., Lee, E., and Wolfe, H. J. (1993) Comparison of indirect and direct in situ polymerase chain reaction in cell preparations and tissue sections. Detection of viral DNA gene rearrangements and chromosomal translocations. Histochemistry 99, 151-162. 

Qian X, Bauer RA, Xu HS et al. In situ hybridization detection of calcitonin mRNA in routinely fixed, paraffin-embedded tissue sections a comparison of different types of probes combined with tyramide signal amplification. Appl Immunohistochem MolMorphol 2001 9 61-69. 

In comparison to most other B cell lymphomas, MCL is relatively unique based on overexpression the cell cycle protein cyclin Dl, which can be identified immunophenotypically in the nuclei of the tumor cells in formalin-fixed paraffin tissue sections (B8, D3, K34, S30, S33, V7, Y4, Z4). The overexpression of the cyclin Dl protein is due to the characteristic genetic translocation found in MCL, t( 11 14), which juxtaposes heBCL-l (PRAD1, CYCLIN Dl) gene on chromosome 11 next to the immunoglobulin heavy-chain gene on chromosome 14 (R12, W7, W8). 

Kertesz V, van Berkel G, Vavrek M, Koeplinger K, Schneider B, Covey T (2008) Comparison of drug distribution images from whole-body thin tissue sections obtained using desorption electrospray ionization tandem mass spectrometry and autoradiography. Anal Chem 80 5168-5177. doi 10.1021/ac800546a... 

Tribollet, E. et al., Localization and quantitation of tritiated compounds in tissue sections with a gaseous detector of beta particles Comparison with film autoradiography, Proc. Natl. Acad. Sci., 88, 1466, 1991. 

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