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 ?
For measurements of the reversal of metachromasy, solutions containing polymer and dye in the ratio 2.0:1.0 were made containing different amount of alcohol.
This stoichiometry indicates that every potential anionic site of the polyanion was associated with the dye cation and aggregation of such dye molecules was expected to lead to the formation of a card pack stacking of the individual monomers on the surface of the polyanion so that the allowed transition produces a blue-shifted metachromasy [27].
The destruction of metachromasy by alcohol and urea is attributed to the involvement of hydrophobic bonding has already been established [29-32].
The ease of reversal of metachromasy can be correlated with its chain length [41].
The concentration of sodium chloride required to reverse metachromasy was greater in case of pincyanolcloride-heparin complex than in the case of acridine orange-heparin complex.
Thus all these thermodynamic parameters suggested the interaction between the anionic sites of the polyanions and the counter ions resulting in aggregation and induction of metachromasy.
Additionally, F I and F III had lowest metachromasy between extract and F II as supported the sulfate analysis (Table 1) due to a relatively lower degree of sulfation (ester sulfate groups, S = O) of the SPs (Rodrigues et al., 2010).
For measurements of the reversal of metachromasy, solutions containing polymer and dye in the ratio 1:2 in case of MO-PC1 and 1:3 in case of MO-PC2 were made containing different amount of alcohol.
The concentrations of sodium lauryl sulphate required to reverse metachromasy was found to be 1 x [10.sup.-4] mol x [L.sup.-1] in the case of MO-PC1 and 1 x [10.sup.-5] mol x [L.sup.-1] in the case of MO-PC2.
The polymers poly(N-vinyl-4-methylpyridiniumiodide) (PC1) and poly(vinylbenzyltriphenylphosphonium chloride) (PC2) induced metachromasy in the dye MO.