Synthesis of the tobacco mosaic virus in blocked spreading of infection

The possibility of infection of tobacco upper leaves with tobacco mosaic virus (TMV) was examined in experiments where the inoculum was imbibed through the cut stem. The inoculum used were: a) a preparation of a virus-specific informosome-like ribonucleoproteins (vRNP) isolated from TMV-infected plants; b) a TMV preparation; or c) a mixture of TMV and vRNP. Multiplication of TMV in upper leaves was observed in neither of the variants; nevertheless in the vascular tissue and/or probably in adjoining parenchymal cells, two kinds of RNA were synthesized: of mol. w. (1.1--1.3) X 10(6) and (0.6--0.8) X 10(6). These RNA were not found in healthy plants in the presence of actinomycin D. The synthesis of genomic TMV RNA is suppressed under these conditions. Thus, some kind of abortive TMV infection takes place under the condition of experimental inoculation of plants through a cut stem. Molecular hybridization with the DNA of recombinant plasmid containing a nucleotide sequence complementary to the 3'-portion of genomic TMV RNA proves that short RNAs synthesized under the abortive infection conditions are TMV-specific. The experiments with differential temperature treatment of N-gene-containing plants under abortive infection conditions suggest that necrotization is not necessarily induced by genomic TMV RNA synthesis.     

Efficacy of 4'-thio-5-ethyl-2'-deoxyuridine (TEDU) and its derivatives in experimental infection in mice caused by herpes simplex virus]

It was demonstrated that several 5'-phosphonates of 4'-thio-5-ethyl-2'-deoxyuridine possessed antiviral activity in vitro and in the murine model of herpes simplex virus type 1 infection. It was shown that the derivatives after intraabdominal administration penetrated effectively into the brain tissue. The agents provided statistically significant increase of the average life span, lower virus titre in the brain and lower lethality when compared to the control group of the animals. It is emphasized that the derivatives were less toxic than the original compound.     

The inhibition by the tumor necrosis factor of the death and DNA fragmentation of lymphoid cells in irradiated rats]

The influence of a tumor necrosis factor, administered 16 h before irradiation of rats, on the radiation response of thymus and bone marrow cells has been investigated. Three and 6 h after irradiation the following indices were analyzed: the number of apoptotic cells in the thymus; the accumulation of polydeoxyribonucleotides and the appearance of single-strand breaks in DNA of bone marrow and thymus cells; and the electrophoretic properties of thymocyte DNA. The injection of a tumor necrosis factor reduced the number of polydeoxyribonucleotides, inhibited internucleosome DNA fragmentation, and did not influence the formation of single-strand breaks in DNA.     

Development of a latex agglutination method for the diagnosis of Pseudomonas aeruginosa infection

The present investigation has revealed the possibility of using different kinds of monodispersed polystyrene latex, produced in the USSR, as carriers in the process of the preparation of antibody diagnosticums intended for the detection of water-soluble slime antigens of Pseudomonas aeruginosa strains belonging to the most widespread serological types. The optimum conditions for the preparation of latex reagents and for making the latex-agglutination test have been experimentally established. The new diagnosticums+ have been shown to be highly species- and type-specific, which permits making judgment on the presence or absence of slime antigens of P. aeruginosa strains belonging to definite serovars in the clinical material under study. The preparations thus obtained have been found to retain their sensitivity for 16 months (the term of observation).