PubMed Health⌕ Search

Biomedical subjects

T I Tikhonenko

Publications and source records attributed to T I Tikhonenko.

At least 37 records · Page 2Linked to original sources

[Enhancement of the transforming activity of simian adenovirus S5 and of the DNA from human adenovirus type I by benzo(a)pyrene and TPA].

Benz(a)pyrene in a concentration of 2.5 micrograms/ml produced a 3.3-fold increase in the transforming activity of simian adenovirus S5 in primary cultures of rat kidney cells. Under analogous conditions TPA increased (2.1 times) the transforming activity of DNA of human adenovirus of type I (AdI). PX5 cells (cotransformed by S5 and benz(a)pyrene) induced tumours in 100% of syngeneic and 81% xenogeneic animals. PX4 cells (transformed by S5 only) induced tumours in 60% of syngeneic animals. Cells transformed by DNA AdI and DNA AdI + TPA did not induce tumours in animals.

Adenoviridae↗

[Conditions of stability for the quaternary structure and antigenic activity of adenovirus hexon].

The procedure of SDS-PAGE was modified by lowering the temperature of protein sample dissociation to allow the separation of denaturated adenoviral hexon chains and native hexon capsomers (trimers) in the same gel. By combining the modified SDS-PAGE with dot and blot radioimmunoassays, the range of stability of the simian adenovirus SA7 hexon quaternary structure and its antigenicity was studied against a number of physical and chemical agents known to dissociate and denaturate proteins. A perfect correlation was found between the hexon native quaternary structure (trimer) and its immunoreactivity with anti-hexon immunoglobulins. The pattern of hexon trimer stability to a wide spectrum of denaturants suggests that its subunits are held together, mainly by hydrophobic interactions, in such a way that the innersubunit contact regions make up the "hydrophobic core" of the hexon molecule.

Adenoviridae↗

[Effectiveness of incorporation of spermine-condensed viral DNA into liposomes. Interaction of liposomes with cells].

DNA from bacteriophage lambda or monkey adenovirus type 7 have been condensed with spermine and included into three types of liposomes: ethereal, obtained by inverted phases technique and by Ca++ fusion. Compact DNA form presents a tor with 100 nm external diameter and 430 nm width. It can be included into 100 nm or larger liposomes. Total preparation contains 15-18% of the required liposomes. Liposomal fractions with included DNA were separated from empty liposomes by step gradient of ficoll 400. Liposomal fraction having included DNA contains 15-18% of common lipid. Liposomal interaction with monkey cell cultures has been studied.

Animals↗

[The use of the cationic detergent dodecyltrimethylammonium bromide for the isolation of influenza virus glycoproteins with subsequent integration of the protein into liposome membrane].

Glycoproteins were isolated from influenza virus with the use of cationic detergent dodecyltrimethylammoniumbromide and attached to preformed liposomes. Liposomal vesicles, thus, acquired their ability for hemagglutination and lysis of chicken erythrocytes. The possibility of using these liposomes for transfer of alien agents into eucaryotic cells is discussed.

Detergents↗

Microinjection of simian adenovirus SA7 (C-8) DNA into the mouse zygotes: differential distribution of viral DNA in organs.

A simian adenovirus SA7 (C-8) DNA was microinjected into fertilized mouse eggs. Thirty-five mice derived from eggs injected with SA7 DNA were screened for the presence of the adenovirus genome in their liver DNA. Eighteen of these mice contained the virus-specific sequences. SA7 DNA was detected in some tissues, but in all cases, viral sequences were absent from muscle and heart DNA. Viral DNA was inherited by 50-70% of the next generation. One mouse that contained about 1 copy of SA7 DNA per haploid genome has been shown to pass it on to five generations, although the integrated viral DNA sustained a considerable structural change between F1 and F3. RNA analysis in various organs of 12 mice has shown the transcription of SA7 DNA to be very infrequent: only in the kidney of one mouse and in the spleen of another did RNA contain SA7-specific sequences.

Adenoviridae↗

The efficiency of genetic transformation of mammalian cells by transfection and microinjection depends on the transferred gene.

The efficiency of genetic transformation of mammalian cells was analysed with respect to the kind of the transferred gene and the selective system. Plasmids pAGO and pAG60 harboring the thymidine kinase gene of Herpes simplex virus type 1 and the bacterial neomycin resistance gene, respectively, were compared concerning their ability to transform mouse Ltk-aprt- cells. Using the calcium phosphate technique the neomycin resistance gene transformed at least ten times more efficiently than the thymidine kinase gene (3 X 10(-3) versus 2 X 10(-4] whereas the difference is even more impressive following microinjection of the plasmids into the nuclei (2 X 10(-1) versus 2.5 X 10(-3]. The neomycin system also proved to be more effective in secondary gene transfer experiments and, thus, seems to be the most convenient marker for cotransfer experiments.

Animals↗

Hind III restriction site map of the human adenovirus type 1 DNA.

The physical map of human adenovirus type 1 DNA was constructed with the Hind III restriction enzyme. Direct comparison of the DNA fragments with those of adenovirus type 2 revealed that the genome of adenovirus type 1 is 200 to 300 base pairs longer. The difference are located outside the region of the inverted terminal repetition within three distinct loci. Fragment Hind III-F of type 1 DNA which is presumed to carry all the genes responsible for in vitro transformation can be separated without considerable contamination by a single electrophoretic step.

Adenoviruses, Human↗

[Formation of DNA-protein links upon interaction between sodium bisulfite and phage DNP].

The conditions for linkage formation in phages Sd and P22 DNP under effects of sodium bisulfite were studied. Th linkage was estimated by the fall in phage infectiosity. After removal of the reagent excess prior to inoculation the modified phage was transferred to various buffers (12 salt systems). The correlation between infectiosity of preparations and changes in their CD spectra in corresponding calt solutions was established.

Bacteriophages↗