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N V Tsvetkova

Publications and source records attributed to N V Tsvetkova.

At least 19 recordsLinked to original sources
PubMed2005

[Genetic control of embryo lethality in crosses between common wheat and rye].

The phenotypic manifestation and genetic control of embryo lethality observed in crosses between common wheat and rye were studied. It was found that crosses between common wheat and inbred self-fertile rye lines L2 and 535 gave rise to ungerminating grains, in which the development and differentiation of the hybrid embryo are arrested. Study of the degree of embryo development in the hybrid grains obtained by crossing common wheat varieties with inbred rye lines L2 and 535 showed that genotypes of the parents affected the ratio between undifferentiated embryos of various sizes. Analysis of this trait was performed by test crosses according to a novel pedigree program with the use of interlinear hybrids and a set of fourth-generation hybrid recombinant inbred lines. Rye line L2 was shown to bear the Eml (Embryo lethality) gene, which terminates the development of the hybrid embryo in amphihaploids. The suggestion of complementary interaction between wheat and rye genes during formation of a "n ew" character in wheat-rye F1 hybrids is discussed. A method of detecting an allele not complementary to the rye Eml allele in wheat is proposed. The proposed test program allows appropriate study of the system of wheat and rye genes involved in complementary interaction in the genotype of a distant hybrid.

Crops, Agricultural↗
PubMed2003

[Analysis of the effects of parental genotypes of rye lines on the development of quantitative traits in primary octaploid triticale. Plant height].

When breeding the primary spring octoploid triticale derived from crosses of various inbred rye lines to wheat Chinese Spring, the effects of the rye genotype and growth conditions on the plant height and proportion of the first, second, and final (pedicle) internodes to the entire stem length were studied. Two triticale groups were examined: homozygotes for the dominant (Ddw1) and recessive (ddw1) alleles of the gene responsible for short stem in rye. In the short stem triticale lines carrying the Ddw1 alleles, the plants were 20 cm shorter on average than those in the ddw1-carrying lines, and the distribution of the two triticale groups overlapped significantly. In both groups, the lines significantly differing in plant height could be differentiated, because of allelic diversity of the additional genes controlling this trait along with the Ddw gene. In most triticale lines, especially in the Ddw1-carrying ones, the plant height was much reduced under unfavorable growth conditions. At the same time, a short-stem line was isolated, which is characterized by ecological plasticity, like the maternal wheat cultivar. In the triticale studied, the stem structure depended on the short-stem rye genotype. The two-year study showed that in the triticale carrying the dominant allele of this gene, the first internode is significantly extended, whereas the upper (pedicle) internode is reduced, which increases plant lodging resistance. The differences revealed between the rye lines as well as their effect on the quantitative triticale traits are discussed in view of a variant of the hybridological analysis, which had been previously proposed for identification and mapping of the correspondent rye genes.

Alleles↗
PubMed1992

[A comparative study of the expediency of using different chemical methods for determining protein in allergen preparations].

Parallel use of some known chemical procedures for measurements of protein in commercial forms of allergens revealed considerable variations in the results, which was due to the nature of the methods used and to admixtures of different substances in the preparations under study. The conclusion on the necessity of using at least two methods of protein determination for the standardization of allergens was made. Preference was given to Bradford's method. As the standardization of allergens manufactured in the USSR is carried out on the basis of the quantitative determination of protein (in PNU), this problem is of not only theoretical, but also practical importance.

Allergens↗
PubMed1991

[The comparative characteristics of different forms of allergens from mites of the genus Dermatophagoides].

The comparative study of allergenic preparations of Dermatophagoides mites [correction of ticks] from different manufacturers and the international standard preparations of such allergens was made. D. pteronyssinus and D. farinae allergens from the USSR and the Netherlands were studied. The samples under study were evaluated in a complex of in vivo and in vitro experiments. The preparations produced in the USSR and in the Netherlands exhibited pronounced specificity, but the allergens of both species from the Netherlands were more active. Some differences in the immunochemical characteristics of the preparations were noted.

Adolescent↗
PubMed1990

[The immunochemical characteristics of allergens].

Modern approaches to the standardization of allergens require the use of not only biological methods, but also a wide range of physicochemical and immunological ones. To obtain Soviet standard samples, the optimum spectrum of methods for their characterization, evaluation and comparison with international standard samples should be definitely selected. After the preliminary study of a number of allergens by different immunochemical methods a set of such methods, including different kinds of electrophoresis, isoelectrofocusing, immunoblotting, etc., are proposed, these methods being considered obligatory for obtaining Soviet standard samples of allergens.

Allergens↗
PubMed1988

[Development of a method for the quantitative determination of Bordetella pertussis toxin and the prospects of its use for diagnosis].

Two variants of the enzyme immunoassay (EIA) systems for the determination of B. pertussis toxin (BPT), the "double sandwich" system and the competitive assay system, have been developed. For the titration of BPT in B. pertussis antigens the use of fetuin as the affinity base is preferable, and not antibodies from different paired animals. Of the two variants, the competitive EIA is more promising for diagnostic purposes.

Animals↗
PubMed1988

[Physicochemical and biological characteristics of preparations of an antigenic complex isolated from the cultivation medium of Bordetella pertussis].

The physicochemical and biological properties of antigenic complexes isolated from the supernatant fluid of the culture medium of B. pertussis, strains 305 and 475, were studied. The preparations obtained from both strains contained proteins, carbohydrates, nucleic acids and lipids. Electrophoresis in polyacrylamide gel revealed the presence of filamentous hemagglutinin, 4 subunits of B. pertussis toxin and agglutinogens in the antigenic complexes of both strains. The preparations of both strains possessed similar toxic properties and, after their detoxification, produced a pronounced protective effect.

Animals↗
PubMed1988

[Evaluation of the level of antibodies to purified meningococcal antigens].

Group B meningococcal antigens, such as polysaccharide, lipopolysaccharide, protein preparation, as well as sonicates obtained from meningococcal cells, groups A, B and C, have been isolated. On the basis of these preparations the parameters of an enzyme immunoassay system for the detection of antibodies to individual meningococcal antigens have been established, and the specificity of the system and the possibility of using it for the evaluation of the level of antibodies to meningococci in human sera have been studied.

Animals↗
PubMed1987

[Development of rational methods for purifying restriction endonucleases].

The work deals with the search for rational schemes of the purification of endonucleases, suitable for the isolation of different enzymes. The scheme using the combination of Blue Sepharose and phosphocellulose has proved to be most universal. The expediency of starting the purification of Haemophilus enzymes on biogel A-0.5m has been established.

Bacteria↗
PubMed1987

[DNA isolated from Streptococcus sp. Thom-1066--the producer of thomicide].

Thomicide is a complex preparation including a bacteriocin-like substance. To localize the determinant responsible for synthesis of the bacteriocin-like substance, DNA of the streptococcus producing thomicide was isolated and studied. Equilibrium centrifugation of the total DNA preparation in the gradient of cesium chloride-ethidium bromide yielded DNA of one density. The total DNA preparation was obtained with alkaline and neutral lysis. Restriction analysis of the streptococcal DNA followed by electrophoretic separation in agarose gel in comparison to the DNA standards of lambda phage and plasmid pBR 322 confirmed the absence of the plasmid or any other extrachromosomal DNA. Chromosomal localization of the determinant encoding biosynthesis of the thomicide bacteriocin-like substance was shown.

Anti-Bacterial Agents↗
PubMed1987

[Possible serodiagnosis of pertussis infection by an immunoenzyme method].

The sera of children and adults with a history of pertussis, as well as the sera of children immunized in three injections, have been studied in the enzyme immunoassay. The levels of antibodies to Bordetella pertussis protein and lipopolysaccharide, and to disintegrated B. pertussis cells have been determined; a serum titer of 1:1,600 and higher is considered as a criterion for the serological diagnosis of pertussis.

Adult↗
PubMed1987

[Purification and substrate specificity of BcmI restriction endonuclease].

A strain producing the new specific restriction endonuclease BcmI has been found in the Bacillus generum. The enzyme has been purified by chromatography on the blue sepharose, phosphocellulose PII, heparin sepharose. The analogous purification has been obtained when the blue sepharose has been substituted for the orange sepharose, the home produced sorbent. The BcmI enzyme has been shown by the substrate specificity definition to be an isoschizomer of the restriction endonuclease ClaI.

Bacillus↗
PubMed1987

[Use of isoelectric focusing for assessing the composition of pollen allergens].

The preparations of allergens and allergoids obtained from ragweed, timothy and wormwood pollen, as well as the preparations of allergens from birch and orchard grass pollen differing in the method of their production, have been studied with the use of analytical isoelectric focusing in a thin gel layer. The composition of the preparations of allergoids differs from that of the allergenic preparations from the pollen of the same plant species by the decreased content of protein components detected in this investigation. The main proteins contained in the preparations of allergoids are distributed in the zone of pH 3.5-4.5. Differences in the composition of different batches of the same allergens, manifested by variations in some protein bands or by their absence, have been noted. Protein components with the isoelectric point in the alkaline zone have been detected only in the preparations of ragweed pollen allergens.

Allergens↗
PubMed1986

[Creation of the library of Bordetella pertussis genome clones and detection of clones containing genes for the synthesis of antigenic determinants of the whooping cough microbe].

Escherichia coli clones containing hybrid phasmids with the inserts of B. pertussis DNA were obtained with the use of a phasmid vector. The total amount of the clones thus obtained was 97,000, which considerably exceeded the volume of the clone library necessary for the detection of individual genes with probability approximating 1. The hybrid plasmids were shown to contain 6-19 kilobases. The screening of the clone library was carried out by means of the enzyme immunoassay (EIA). The assay was aimed at detecting clones containing the genes of the subunits of B. pertussis lymphocytosis-stimulating factor (LSF). The EIA techniques used in this investigation were based on the capacity of LSF for binding with fetuin. Six clones giving positive response were detected. These data suggest the presence and expression of the genes controlling the synthesis of the antigenic determinants of LSF in E. coli cells.

Antigens, Bacterial↗
PubMed1986

[Antipertussis immunity studied by immunoenzyme analysis].

The levels of antibodies to disintegrated Bordetella pertussis and its individual fractions (protein and polysaccharide) in children immunized with different batches of adsorbed DPT vaccine have been determined with the use of EIA techniques. The background level of antibodies in the control groups has been determined, and in immunized children the levels of antibodies to disintegrated B. pertussis and its protein fraction have been shown to considerably exceed the levels of antibodies to lipopolysaccharide.

Adult↗