DNA-like duplexes with repetitions. III. Efficient template-guided chemical polymerization of d(TGGCCAAGCTp).

Self-association of a decanucleotide d(TGGCCAAGCTp) in an aqueous solution is shown by UV spectroscopy, CD and sedimentation analysis to yield a pseudopolymeric (concatemeric) duplex having a geometry similar to that of DNA B-type. It is demonstrated that in conditions when the concatemeric duplex is stable a water-soluble carbodiimide induces efficient polymerization of the 3'- or 5'-phosphorylated decanucleotide, and the resulting polymers d(TGGCCAAGCTp)2-10 contain only natural phosphodiester bonds. In conditions optimal for template-guided polymerization of d(TGGCCAAGCTp) the overall yield of 20-100-member polynucleotides exceeds 90%.

[Study of human diploid cell strains for the presence of oncornavirus determinants].

The WI-38 strain of human diploid cells (HDC) and two strains, L-58 and L-63 isolated in Moscow Research Institute of Virus Preparations were examined in the course of sequential passages for the presence of primate oncornaviruses and their antigens. In parallel, the tumorigenic capacity of the cells was tested by inoculating them into the cheek pouch tissue of Syrian hamsters. In all cases the examined HDC cultures contained no oncornavirus particles or their antigens and in no case showed any infectious activity determined in the KC-test.

[Membrane phospholipids of the rat liver endoplasmic reticulum normally and in the early stage of carcinogenesis].

There were found certain changes in the total content of phospholipids as well as in the content of their separate fractions in the membranes of endoplasmic reticulum in the rat liver at early stages of carcinogenesis. In the first week under the carcinogen DENA exposure a considerable reduction of the total phospholipids content was noted in the fraction of granular endoplasmic reticulum, while in agranular reticulum during this period of embryogenesis the total content of phospholipids is not changed, but subsequently the former increases as compared with normal values. During the whole period of carcinogenesis under study changes in the phospholipid content are observed in both fractions of endoplasmic reticulum membranes, the greatest changes being noted in the fractions of lysophosphatidicholines, phosphatidilcholines, and phosphatidilinosites.

[Immunological characteristics of LPV oncornavirus produced by T-9 human cell line].

The results of immunological study of oncornavirus (LPV strain) produced by a continuous human T-9 cell line are presented. The method of immunodiffusion in agar revealed the following constituent antigens in the virus: (a) those identical to internal and external antigens of Mason-Pfizer oncornaviruses particles; (b) those specific only for LPV virus and not common in other known oncornaviruses of mammals. These antigens were common in LPV virus from T-9 culture and from xenogeneic T-BHK culture in which Mason-Pfizer virus antigens were absent completely; and (c) interspecific antigen of oncornavirus C type present in minimal amounts.