metachromasia


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metachromasia

 [met″ah-kro-ma´zhah]
1. failure to stain true with a given stain.
2. the different coloration of different tissues produced by the same stain.
3. change of color produced by staining. adj., adj metachromat´ic.

met·a·chro·ma·si·a

(met'ă-krō-mā'zē-ă),
1. The condition in which a cell or tissue component takes on a color different from the dye solution with which it is stained. Synonym(s): metachromatism (2)
2. A change in the characteristic color of certain basic thiazine dyes, such as toluidine blue, when the dye molecules are bound in proximate array to tissue polyanionic polymers, such as glycosaminoglycans.
[meta- + G. chrōma, color]

metachromasia

The property of a tissue, due to the presence of sulfated polysaccharides and sialic acid mucins, which causes it to stain differently from the surrounding structures and from the colours used in the dye.

met·a·chro·ma·si·a

(met'ă-krō-mā'zē-ă)
1. The condition in which a cell or tissue component takes on a color different from the dye solution with which it is stained.
Synonym(s): metachromatism (2) .
2. A change in the characteristic color of certain basic thiazine dyes, such as toluidine blue, when the dye molecules are bound to tissue polyanionic polymers.
[meta- + G. chrōma, color]

metachromasia

The variations in colour produced in different parts of a tissue when stained with a single dye.
References in periodicals archive ?
Zaid, "Metachromasia in the exfoliated vaginal cells of Awassi ewes," Kufa Journal for Veterinary Medical Sciences, vol.
We observed a large peak corresponding to ~90% of the total hexuronic acid in the sample that eluted with ~400mM NaCl without showing any significant metachromasia. These properties are characteristic of HA when it is applied to this column.
This finding shows that other specific factors beyond polymer charge density, such as sulfate groups, are required for metachromasia in the presence of DMB.
One concludes that malathion has a direct cytotoxic effect causing coiling of the tail, with increase of metachromasia of the chromatin of the spermatozoa and altering the sperm count.
It has often been stated that in experimental amyloidosis the metachromasia with gentian or methyl-violet is the only reaction which is distinct, the characteristic coloring with iodin or iodin sulphuric acid being absent, or much less pronounced (Bailey).
For observations of general morphology (with a light microscope) and for studies of metachromasia, cells were fixed in 10% formalin in FSW and stained with 1:5000 methylene blue.
The electrophoretic profile also showed similar mobility of both polysulfated on gel, in which M I exhibited a single band; therefore, it was a homogeneous crude SPs extract in charge density than that obtained from the M II which revealed a polydisperse crude SPs extract and weak metachromasia, suggesting a low sulfate content in the sample (RODRIGUES et al., 2011a and c; QUINDERE et al., 2013).
All fractions indicated a relatively low carbohydrate concentration, but with the highest metachromasia verified for fraction eluted with 1.2 M.
The obtained fractions (5 mL) were monitored by metachromasia with 1.9-dimethylmethylene blue (FARNDALE et al., 1986) on an Elisa reader (AMERSHAM BIOSCIENCES, model BIOTRAK II) set at 525 nm.
Fractions of 3 mL were collected in a collector FRAC-920 (90 mL [h.sup.-1]) and monitored by metachromasia with the 1,9 dimethylmethylene blue (Sigma-Aldrich) at 525 nm (AMERSHAM BIOSCIENCES ULTROSPEC 1100) (FARNDALE et al., 1986).