[Expression of human interferon beta in the mammary gland of transgenic rabbits].

A biotechnological system for the production of human beta interferon was developed on the basis of a hybrid gene constructed from the coding sequence of the beta interferon gene inserted into the first exon of the sheep beta lactoglobulin gene. It is intended for the expression of human beta interferon in mammary glands of transgenic animals. Two lines of transgenic rabbits were obtained using the hybrid gene.

[Efficacy of various methods of a reporter gene transfer to chicken embryonic cells].

The methods of transfection ofa plasmid with a reporter gene involving DNA injection into chicken embryonic cells were studied. The parameters of the efficient transfection of chicken blastodermal cells with a foreign gene have been determined (20-24 and up to 40% in culture and embryos, respectively). A high efficiency of transfection of primordial germ cells isolated from the gonads has been obtained after DNA injection into the dorsal aorta of 2.

[The course of the nearest postoperative period in patients with injuries of the spleen].

The authors have analyzed the course of the postoperative period in 410 patients operated on for isolated, combined and multiple traumas with injuries of the spleen. The character of the operation (splenectomy, splenectomy with autolientransplantation, organ preserving operations) had no significant influence on frequency of complications or lethality.

[Production of cloned bovine embryos by somatic cell transfer into enucleated zona-free oocytes].

Cloned bovine embryos were produced at the blastocyst stage. Prior to enucleation, oocytes were freed from the zona pellucida. Fibroblasts isolated from the bovine fetus were used as nuclear donors.

[A study of factors affecting the efficiency of electrofusion of enucleated eggs and cell-donors of nuclei].

We studied the capacity of rabbit oocytes for electrofusion with morula blastomeres and fetal fibroblasts. The morula blastomeres fused with aging ooplasts more readily than the fetal fibroblasts: 92.9 versus 63.

[Effect of age of cell donors of nuclei on effectivness of developing cloned rabbit embryos].

We studied the capacity of nuclei of rabbit fibroblasts taken from various developmental stages for reprogramming in the cytoplasm of mature aging enucleated oocytes and development of the cloned embryos to the preimplantation stages. A negative correlation was found between the age of an animal--donor of fibroblasts and efficiency of the development of cloned embryos (rmorula-blastocyst = -0.826, rblastocyst = -0.

Isolation of milk-clotting enzyme from transgenic sheep milk and its comparison with calf chymosin.

Technology for preparation of chymosin from milk of transgenic sheep has been elaborated. Purification of the preparation by ion-exchange chromatography on aminosilochrom and biospecific chromatography on bacitracin-Sepharose yielded homogeneous active enzyme. Hydrolysis of protein substrates (hemoglobin, BSA, and sodium caseinate) by the transgenic sheep chymosin and stability of the enzyme at various values of pH were studied.

[The effect of serum starvation on the efficacy of the nuclear reprogramming of rabbit embryonic fibroblasts].

Successful transplantation of mammalian nuclei from differentiated cells has become possible after the application of original methods directed at the synchronization of cell cycles of the donor cell and recipient cytoplasm. We obtained a line of rabbit fetal fibroblasts which was used to study factors affecting the success of reprogramming. The nuclei of fetal fibroblasts (up to the 10th passage inclusive) proved to be capable of reprogramming and ensuring development of the cloned embryos until the preimplantation stages.

[Effect of rifampicin on the synthesis of antibodies to fraction I of vaccine EV].

Multifactorial analysis was used to study the influence of rifampicin on the dynamics of synthesis of antibodies belonging to IgM and IgG classes in mice immunized by fraction I of the vaccinal strain EV. Equations and quadric surfaces describing individual dynamics of antibody formation within a wide range of antibiotic doses and time of antibody content determination were developed by the experimental data. It was shown that within the range of the doses corresponding to the therapeutic ones in man rifampicin stimulated antibody formation.

[The transplantation of rabbit embryos].

Criteria of morphological assessment of zygote quality and various transplantation conditions have been studied to achieve implantation in the host female and obtain the offspring. The data obtained indicate that implantation of 10-15 zygotes with light homogeneous cytoplasm and distinct pronuclear membrane per recipient female may be regarded as optimal conditions.

[Several properties of complexes of polynucleotides with aromatic amino acid amides of oligonucleotides].

Residues of Phe, Tyr and Trp in the complexes of their oligonucleotide amidates and polynucleotides of A-U of G-C nucleotide composition are most likely localized in the minor groove of the Watson--Crick part of the triple helix where they interact with bases but do not intercalate into the helix. Formation of the complexes is accompanied with a change in the relative localization of amino acids and bases. The major geometrical parameters of the triple helices of the complexes are not changed by the residues of aromatic amino acids (according to CD data).

[Nucleotide and oligonucleotide derivatives--a research tool of molecular biology].

The work of the authors are discussed, that they have been engaged in since the late forties, on synthesis and investigation of mono- and oligonucleotide derivatives. One class of mixed biopolymers (mono (oligo) nucleotides) is used to demonstrate the effect of covalent and noncovalent intramolecular interactions on the character of various protein-nucleic acid contacts. General approaches to creating regioselective reagents are outlined, that can be widely used for modification of both proteins and nucleic acids.

[The secondary structure of nucleotidyl-(5' bound to N)-amino acids containing different heterocyclic bases and amino acids].

Nucleotidyl-(5' leads to N)-amino acids containing different heterocycle bases: adenine, guanine, hypoxanthine, cytosine, uracyl, and aromatic amino acids: phenylalanine, tyrosine and tryptophan, have been investigated by proton magnetic resonance and circular dichroism. For all the compounds studied folded conformation have been shown stabilized by hydrophobic interaction in aqueous solution. The comparison of the results of the studied nucleotidyl-(5' leads to N)-amino acids unable us to build four secondary structure types in these very compounds.

Dependence of noncovalent interactions of benzene and adenine rings on distance between them in adenylyl-(5' yields N)-omega-arylalkylamines.

A series of adenylyl-(5' yields N)-omega-arylalkylamines, containing from one to six methylene groups in the amino component, was studied by methods of nuclear magnetic resonance and circular dichroism. It was shown that independently of the length of the aliphatic chain of the amine convergence of the adenine and benzene rings and a hydrophobic interaction between them occur. The plane of the benzene ring is inclined toward the adenine ring, which has an anticonformation relative to the ribose.