[Biological functions of allantoin].

A historical review of allantoin research is presented. An increased allantoin level in the trophoblast and serum of pregnant women has been demonstrated. Allantoin concentration decreased in placental tissues and increased in the serum in developing placental insufficiency.

[The effect of oxidative stress on nitrosomethylurea-induced mutagenesis in sunflower Helianthus annuus L].

The effect of hyberbaric oxygenation on mutagenicity of nitrosomethylurea (NMU) was examined. It was shown that in the regimes studied, hyperbaric oxygenation enhances the NMU mutagenic effect both on the nuclear and on the plastid genetic material of sunflower, but do not increase intensity of free-radical reactions and do not induce plastid mutations and chromosome aberrations per se. At high concentrations inducing chromosome aberrations (0.

[Cytogenetic effect of temperature on the sunflower varieties].

The influence of increased temperature on the intensity of fission and level of chromosome aberrations (ChA) in root meristeme cells of two lines of sunflower seedlings was studied. Within the first hour of seed germination, the temperature of 40 degrees C reduced proliferation activity of root meristeme cells line 3629 for almost the next 15 h of growth. Heat stress (HS) blocks the beginning of cell fission in the plastome mutant en-chlorina-5.