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A V Zuev

Publications and source records attributed to A V Zuev.

8 recordsLinked to original sources
PubMed1989

[Accessory left superior vena cava].

The authors conducted contrast study of the position of the cavacatheter in all patients treated in the period of 12 months in the thoracic surgery department and the anesthesiology-resuscitation department who required long-term intensive therapy. In 61 of these patients the catheter was introduced through the left subclavian vein. An accessory left superior vena cava (ALSVC) which drained through the coronary sinus into the right atrium was found in 3 patients (4.9%). Study of the anatomical features of this venous anomaly led to the conclusion that prolonged infusion therapy through an ALSVC is undesirable.

Catheterization↗
PubMed1985

[Localized mutagenesis of the tetracycline gene in the plasmid pBR322 induced by sodium bisulfite in vitro].

The technique of localized in vitro mutagenesis in the cohesive ends of plasmid pBR322 DNA has been elaborated (separately for BamHI and HindIII sites). Plasmid DNA digested by restriction endonucleases has been treated with sodium bisulphite deaminating cytosine to form uracil in single stranded DNA (cohesive ends of the plasmid). The mutagenized plasmid DNA, free of mutagen, has been treated with bacteriophage T4 ligase. E. coli C600 cells were subsequently transformed by the ligated DNA preparation. The clones having tetracycline gene mutagenized represented 4.0-11.1% and 1.2-3.1% among HindIII and BamHI mutants, respectively, selected as TcR----TcS transformants. Selection of mutagenized DNA by the second endonuclease restriction has increased the mutant yields up to 55.6-78.0% and 10.0-75.4%, respectively. The yield of TcS mutations in the control DNA treated at all stages of experiment, except for mutagen treatment, has reached 0.06% and 0.2%, respectively.

DNA Restriction Enzymes↗
PubMedDate not supplied

Repair of 8-methoxypsoralen monoadducts and diadducts in bacteriophages and bacteria.

The combined action of 8-methoxypsoralen (8-MOP) and light with lambda greater than 310 nm on bacteriophages and bacteria results in the formation of the following two types of photo-products in the DNA: monoadducts, in which 8-MOP is covalently bound to a pyrimidine base, and diadducts or cross links, in which the 8-MOP is covalently bound to two pyrimidines from complementary strands. The method of repeated irradiation has been proposed for analyzing the degree of lethality of the photoproducts in DNA. According to this method, the preparation is freed of free 8-MOP molecules after the first irradiation and then irradiated for a second time. In this case the monoadducts are converted into cross linkages between the strands. Approximately 3-10(-9) cross links/Dalton-min form in Escherichia coli DNA during the first irradiation. The rate of the formation of cross links drops by a factor of about 2 during the repeated irradiation. It has been shown that the 8-MOP monoadducts are repaired by the uvr system just as efficiently as are lethal photoproducts of the cyclobutane pyrimidine dimer type. Lethal cross linkages in bacteria and phages are repaired by the joint action of the uvr, recA, and lex systems. A scheme has been proposed for the repair of cross linkages in one genome by these systems. The photoreactivating enzyme is inactive on DNA subjected to the combined action of 8-MOP and light. The kinetics of the repair of monadducts in bacteria and phages with various defects in the repair systems have been studied. It has been shown that the products of genes recA and lex take part in the repair process according to an excision-resynthesis method. The use of the method of repeated irradiation with 8-MOP as an express method for detecting repair systems of the uvr type in cells has been proposed.

Caffeine↗