Biomedical subjects

J Erenpreisa

Publications and source records attributed to J Erenpreisa.

23 records · Page 2Linked to original sources

PubMed1979

Anisotropic staining of apurinic acid with toluidine blue.

Using normal rat liver imprints, studies were carried out on the effects of histone extraction and the formation of aldehyde groups from deoxyribose on anisotropic toluidine blue staining of depurinized DNA after sodium bisulfite treatment. The anisotropic effect of bisulfite was found to be determined by binding of bisulfite ions to the aldehyde groups of apurinic acid which, together with free phosphate groups of DNA ensure coparallel attachment of the dye molecules. It was also shown that at pH 5.0 toluidine blue binds with both the phosphate and aldehyde groups of apurinic acid, to give anisotropic staining.

Animals↗

PubMed1979

Influence of some aldehyde blocking agents on staining of depurinized DNA with cationic dyes.

Rat liver, spleen and Walker carcinosarcoma imprints were subjected to depurinizing Feulgen hydrolysis and then treated with blocking agents of aldehyde groups. Such blockators as sodium bisulfite and hydroxylamine which multiplay additionally anionic groups in DNA and intensify the reactions with cationic dyes, ensuring anisotropic staining. Hydrazine lowers the binding of carionic dyes to DNA, instead phenylhydrazine, completely blocks both aldehyde and phosphate groups. When the imprints were treated with 2.4-dinitrophenylhydrazine, aldehyde and phosphate groups of apurinic acid were blocked, and DNA staining by cationic dyes occurred only on account of nitrogroups of the blocking agents which have been used. The staining reaction of cationic dyes after the use of anionogenic blocking agents of aldehyde groups is prospective not only for revealing DNA but also for several other compounds with natural or potential aldo- and ketogroups. However the reaction with phenylhydrazine can serve as a staining without removal of DNA prior to staining as an optional procedure.

Aldehydes↗

PubMed1978

Feulgen hydrolysis at refrigerator temperature.

In order to search for the better FEULGEN hydrolysis conditions, the 2 kinds of hydrolysis with 5 N HCl - at room temperature and at refrigerator temperature - were comparatively studied on rat liver imprints. 2 reactions were used: with the SCHIFF reagent binding to aldehyde groups and with methylene blue staining phosphate groups of DNA. Cytophotometry was coupled with morphological examination of stained nuclei. It was found that 1. cold hydrolysis has no substantial advantage when revealing DNA with the SCHIFF reagent but 2. it has undoubtful profit to reveal DNA, and in particular its acid-labile fraction, when staining with methylene blue. With the cold hydrolysis-methylene blue technique at least 3 categories of DNA with different acid-lability can be revealed and characterized morphologically in rat liver nuclei.

Animals↗

PubMed1977

Evaluation of Feulgen reaction performed on unfixed smears.

Feulgen reaction--both the original one with Schiff reagent and the modified one with toluidine- or methylene blue, pH = 4.0--can be carried out on air-dried smears without fixing. Hydrolysis--5 n HCl at room temperature should be 15 to 20 min for the original and 5 to 10 min--for the modified reaction. Binding of the dyes is stoichiometric in both cases.

Animals↗

PubMedDate not supplied

Comparative study of cytochemical tests for sperm chromatin integrity.

Tests were carried out on sperm from 40 fertile and infertile men to evaluate 2 DNA in situ denaturation methods using acridine orange (AO; the modified Rigler-Roschlau method and the Tejada method), alongside routine aniline blue (AB) and toluidine blue (TB) tests in our modification, and in order to estimate and compare the practical value of different in situ cytochemical tests for sperm chromatin structure. In addition, the methods were applied to rat and boar spermiogenesis models. The sperm heads with abnormal versus normal chromatin structure were specified as orange-red versus green by the AO method, blue versus uncolored by the AB method, and purple-violet versus light blue by the TB method. A good correlation for the proportion of sperm heads with abnormal chromatin structure was found among all the methods (r = .63-.70; P < .01), which characterized all 4 techniques as sensitive enough to estimate in situ sperm DNA integrity. In our study, the average value of abnormal cells was 17% +/- 3.8% and 30.2% +/- 6.8% for the fertile and infertile groups of men, respectively, setting a threshold of 95% probability at 23% as judged by the Rigler-Roschlau method. This compared with 23.9% +/- 7.5% and 52.1% +/- 20.8% (P < or = .05) for the fertile and infertile groups, respectively, setting a threshold at 31%, as judged by the Tejada method. The technical advantages and disadvantages of each method are briefly reported. Key words: Fertility, DNA normality, sperm maturation.

Acridine Orange↗