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M K Dutt

Publications and source records attributed to M K Dutt.

At least 55 records · Page 3Linked to original sources
PubMed1979

Spectrophotometric and cytochemical studies on azures A, B and C.

The cytochemical use of azures A, B and C, propared with either N HCL and potassium metabisulphite or with sodium hydrosulphite in tissue sections were investigated. Both in situ absorption curves of nuclei stained with each of these dye-SO2 reagents as well as in vitro absorption data of acqueous solutions of the dyes are also presented. It has been pointed out that the mechanism of staining with azure A-SO2 and azure C Eosinate-SO2 is the same as that of the conventional Feulgen reaction with Schiff reagent but that of staining with azure B-SO2 is by the modified Feulgen reaction because this dye does not contain any primary amino group.

Animals↗
PubMed1979

Cytochemical specificity of acridine red towards RNA and depolymerised DNA.

The paper contains an account of the use of the basic dye, acridine red, of the xanthene group, for staining RNA and depolymerised DNA. The in situ absorption curve of nuclei stained with acridine red indicates a peak of maximum absorption at 560 nm, whereas in vitro absorption characteristics of an aqueous solution of the dye indicate the peak at 550nm. The possibility of using acridine red as a substitute for pyronin, when staining is required for RNA only or in methyl green-acridine red sequence for localising DNA and RNA has been discussed.

Acridines↗
PubMed1979

Modified Feulgen staining of DNA with aqueous solution of pinacyanol.

The paper reports on the use of a quinoline dye, pinacyanol, towards staining of acid hydrolysed DNA. The dye as an aqueous solution can be used after treatment of mammalian tissue sections in concentrated phosphoric acid at 5 degrees C for 20 min followed by hydrolysis in 6N HCl at room temperature for 15 min, for staining DNA-aldehyde molecules. It has also been observed that staining of DNA-phosphate groups is also possible in sections treated with cold concentrated phosphoric acid after selective extraction of RNA. Both in situ absorption characteristics of stained nuclei as well as in vitro absorption data of an aqueous solution of the dye have been presented. It has been suggested that staining DNA-aldehydes with pinacyanol, without any primary amino group in its molecules is due to a modified Feulgen reaction.

Animals↗
PubMed1979

Increased shelf-life and feulgen staining intensity of a modified trichloracetic acid-Schiff reagent.

Two modified formulae for the preparation of trichloracetic acid (TCA)-Schiff reagent have been presented in this communication. The modifications involve addition of 250 mg or 500 mg of trichloracetic acid per 100 ml of a 0.5% aqueous solution of basic fuchsin in place of NTCA which means 1.63 g of TCA per 10 ml of distilled water to be added to 100 ml of the dye solution. The use of TCA-Schiff reagents prepared by the modified method reveals a considerably faster Feulgen staining, a more intense colouration of the nuclei and a longer shelf-life of the dye-SO2 reagents as compared with the standard TCA-Schiff of Bloch and Godman. Possible interpretations for these phenomena have been presented.

Animals↗
PubMed1979

Hoffman's violet and dahlia as specific stains for animal chromosomes.

The paper deals with staining of the chromosomes of animal testicular materials with two basic dyes, Hoffman's violet and dahlia of the triphenylmethane group, following iodine-dye procedure. The important finding, as presented herein, is that iodinated alcohol after staining can be substituted with various acids, both organic as well as inorganic, all of which act as trapping agent preventing leaching of the dye that binds with the chromosomal DNA. It is clear from this study that RNA is not involved by this process of staining, since treatment of stained sections with cold phosphoric acid at 5 degrees C for 20--25 min and then stained also reveals perfect colouration of the chromosomes without any cytoplasmic staining. The in vitro absorption properties of Hoffman's violet have also been presented herein. The probable mechanism of action of these dyes has been suggested.

Animals↗
PubMed1979

Shelf-life of citric acid-toluidine blue O-SO2 and its influence on Feulgen staining.

The paper reports on the preparation of a dye-SO2 reagent employing a Schiff-type dye, toluidine blue O. The method is to replace 5 ml of N HCl per 100 ml of the dye solution by citric acid. The usual potassium metabisulphite is then added. The pH of this new modified dye-SO2 reagent is 2.5 as against 1.6 for the hydrochloric acid-toluidine blue O-SO2. The shelf-life of this newly developed dye-SO2 reagent is four weeks with appreciable reduction of staining intensity after this period as compared with that of a freshly prepared dye-reagent with N HCl. A possible interpretation for the observed phenomenon has been suggested.

Animals↗
PubMed1979

Detection of DNA in mammalian tissues following removal of RNA with cold phosphoric acid.

The paper deals with the staining of nuclei in mammalian tissue sections with night blue, belonging to diphenylnaphthylmethane group and is devoid of any primary amino group in its molecules but is provided with a secondary amino group and tertiary amino groups. Staining of the DNA-phosphate groups with an aqueous solution of night blue depends upon selective removal of RNA from formalin-fixed mammalian tissues by the use of cold concentrated phosphoric acid for 20 min or 75% phosphoric acid in the cold for 2 h. Moreover, sections from which RNA has been extracted can be hydrolysed in 6N HCl at room temperature for 15 min and then can be stained with the aqueous solution of the dye. Sections of tissues after only acid hydrolysis and staining also reveal very satisfactory staining of the nuclei. Possible mechanism of staining has been suggested.

1-Naphthylamine↗
PubMed1979

Fixation of mammalian tissues in different fixatives and its influence on the staining with methyl green-pyronin.

This investigation is a study on the role of fixation of different mammalian tissues in different fixatives as well as in 10% neutral formalin containing different metal cations and its effect on the staining with the dye-mixture, methyl green-pyronin. The results indicate variation in the colour of the nuclei in tissues fixed in the different fixatives. The possible role of the fixatives on nuclear colouration has been discussed.

Animals↗
PubMed1979

Feulgen type staining with Hoffmann's violet-SO2 under exposure to UV rays.

The paper contains an account of the use of Hoffmann's violet-SO2 under exposure to UV rays during staining acid-hydrolysed DNA of mammalian tissue nuclei. Preparations stained with Hoffmann's violet-SO2 without exposure to UV rays reveal extremely pale violet nuclei but when stained under the influence of UV rays show a considerably faster reaction resulting in a very much deeper staining of the nuclei. Sections after staining with this dye-reagent require n-butanol as differentiating reagent. Possible interpretation for the increase in staining ability of this dye-reagent under exposure to UV rays has been elucidated and the reason for considering the reaction as Feulgen type has been discussed.

Adrenal Glands↗
PubMed1979

Hydrochloric acid-sodium thiosulphate-Schiff reagent and its cytochemical properties.

Cytochemical properties of modified Schiff reagent, prepared with 5 ml of N HCl and 1.0 g of sodium thiosulphate, the latter replacing potassium metabisulphite, have been presented in this communication. It has been seen that such a modified Schiff reagent has a slightly elevated pH as compared with that of the conventional Schiff reagent. It has also been found that this modified Schiff reagent has a much longer shelf-life and that the staining intensity produced by this dye-reagent is more than those of the usual Schiff reagent prepared with N HCl and potassium metabisulphite (potassium pyrosulphite, K2S2O5). Possible mechanism as to why the staining intensity of the nuclei is more with this modified Schiff reagent as well as the reason as to why its shelf-life is increased compared with those of the conventional Schiff reagent have been discussed.

Animals↗
PubMed1979

Staining of DNA-phosphate groups with a mixture of azure A and acridine yellow.

This paper deals with staining of DNA-phosphate groups with a mixture of an equal parts of aqueous solution of azure A and acridine yellow in a 1:1 proportion and also embodies a study of the absorption properties of the stained nuclei. It also embodies results of sequential staining of nuclei stained first with azure A followed by staining with acridine yellow and vice versa, after extraction of RNA with cold phosphoric acid. The results indicate that the absorption peaks of nuclei differ from those of nuclei stained for DNA-aldehyde molecules with azure A-SO2 or acridine yellow-SO2. The in vitro absorption characteristics of an aqueous solution of azure A and those of an aqueous solution of acridine yellow are also presented herein. The conclusion obtained from this study is that all the phosphate groups of DNA do not take part in the staining process when staining is carried out with azure A or acridine yellow alone after after RNA has been extracted. This is because the nuclei stained with these dyes sequentially show the presence of acridine yellow-DNA and azure A-DNA complex.

Acridines↗
PubMed1978

A new rapid method for selective extraction of RNA from fixed mammalian tissues.

Treatment of formalin-fixed mammalian tissues with concentrated or 50% phosphoric acid at 5 degrees C for 20 and 50 min. respectively reveals complete extraction of RNA as judged by methyl green followed by staining with pyronin. This procedure also causes depolymerisation of DNA as indicated by the red staining of the nuclei. Sections treated with concentrated phosphoric acid at 5 degrees C for 30 min. causes disruption of the double helical structure of DNA what results in the depression of the pyronin staining. Similarly treated sections show Feulgen positive nuclei. Treatment of sections in 25 % phosphoric acid at 60 degrees C for 15 min. followed by staining with methyl green and pyronin show red nuclei, nucleoli and the cytoplasm. This indicates that extraction of RNA is only possible in cold and not at elevated temperature.

Animals↗
PubMed1978

Sequential staining of DNA-aldehyde with Schiff's reagent and acriflavine-SO2.

Acid hydrolysed DNA of rat liver was stained with Schiff's reagent at pHs 1.7 or 3.0 followed by staining with acriflavine-SO2 at pH 2.0 as well as with acriflavine-SO2 followed by Schiff's reagent at pH 1.7 or 3.0. Nuclei stained with Schiff's reagent at pH 1.7 were brown-yellow and an analysis of their absorption characteristics revealed two peaks--one at 470 nm and the other at 570 nm. Although nuclei stained with Schiff's reagent at pH 3.0 followed by acriflavine-SO2 were deep magenta in colour, they also showed similar peaks of maximum absorption. Identical peaks were also seen when the sequence of staining was reversed. It is suggested that in the conventional Feulgen-type reactions only some of the DNA-aldehyde molecules are stained; the remaining molecules can be stained by sequential application of another Schiff or Schiff-type reagent such as acriflavine-SO2. The possible mechanism of staining in these cases has been discussed.

Acridines↗