The estimation of the amount of diphtheria toxin and its activity by various tests in the dynamic cultivation of Corynebacterium diphtheriae PW8]

Direct correlation between the results of tests for the biological activity of diphtheria toxin, carried out in vivo guinea pigs and in vitro in the microcytotoxicity test in CHO cell culture, has been established, which makes it possible to use the latter as one of the methods for the rapid, reproducible and economic evaluation of diphtheria toxin. The qualitative and quantitative evaluation of diphtheria toxin in the enzyme immunoassay with the use of monoclonal antibodies and in the microcytotoxicity test demonstrates that these two tests, when used for controlling cultivation processes, have essential advantages over the flocculation test as regards their specificity and information content.     

Comparative ultrastructural analysis of the in vitro microspore embryoids and in vivo zygotic embryos of wheat as a basis for understanding of cytophysiological aspects of their development

Ultrastructures of in vitro microspore embryoids and in vivo zygotic embryos of spring wheat have been analyzed and compared. Along with the similarity of ultrastructural characteristics of embryoid and embryo cells at the corresponding developmental stages, some differences have been revealed. Unlike embryos, embryoid cells are characterized by lipid inclusions and numerous mitochondria with well-developed internal membranes. According to our hypothesis, lipids represent an alternative energy source required for active cell divisions in the forming embryoids. Unlike embryos, since the earliest developmental stages, embryoid cells accumulate a significant amount of starch and then utilize it during the organogenesis and germination. A conclusion has been made that embryoid cells create their own reserve of carbohydrates, which is then mobilized during their development. The concept of T.B. Batygina (1987, 1997, 2014) about the universal character of the plant morphogenesis in vivo, in situ, and in vitro has been confirmed. The prospects for the use of microspore embryoidogenesis in vitro as a model to study cytophysiological aspects of zygotic embryogenesis in vivo are discussed.     

Changes in the microcirculatory bed and tissue metabolism in chronic regional arterial hypotension

Blood pressure was reduced in the hind part of rats by narrowing the aorta in regions distal to renal artery ostium. Resetting of microcirculatory bed (m. extensor hallicis propius) was revealed in arterial hypotension, characterized by resistance vessel dilatation ensuring the decrease in hydravlic resistance, thus facilitating blood supply and tissue metabolism normalization, irrespective of marked reduction in perfusion pressure.     

Formation and Function of the Legume–Rhizobium Symbiosis of Soybean Plants while Introducing Bacterial Strains from the Genera Azotobacter and Bacillus

The effects of bacteria belonging to the genera Azotobacter and Bacillus in a mixed culture with Bradyrhizobium japonicumstrains on the formation and function of the legume–rhizobium symbiosis of soybean plants were studied. The data showed that the bacterial compositions B. japonicum 634b +B. subtilis 5, B. japonicum 634b + A. chroococcum 20, and B. japonicum 10k + A. vinelandii56 with a cell ratio of 1 : 0.1 increased the number and weight of root nodules as well as the height and weight of the aboveground plant parts in almost all cases by 22–105% compared with the control variants. These binary microbial cultures may be used for the development of combined bacterial preparations for soybean.