Cortical and zona reactions of heat-activated mouse eggs

Oocytes collected from superovulated Swiss albino mice were activated by heat-shock and/or fertilized in vitro. Electron microscopy showed that the cortical reaction in heat-treated eggs was incomplete. Digestion of the zona pellucida of untreated, heat-treated and fertilized eggs by pronase showed that zona pellucida hardening did occur but was weaker in heat-treated than in fertilized eggs. Fertilizability of heat-treated eggs decreased 1.5 h after heating. We concluded that, in heat-activated eggs, changes occur at the zona and plasmalemma but they are not identical with those in fertilized eggs.     

Metabolic indices of proteolysis of the blood serum in dogs in the early period following uniform whole-body gamma irradiation

Free amino acid concentration and proteinase inhibitor content were studied during the first 48 h following whole-body uniform gamma irradiation of dogs (LD30/50 and LD90/45). The contribution of metabolic profile features to individual radiosensitivity is discussed on the basis of the retrospective analysis of the initial level of metabolic indices in animals survived and died after irradiation. The comparison of the dynamics of changes in the indices under study in the animals died after exposure to different radiation doses permitted to suggest the important role that early hyperactivation of proteolysis played in the development of metabolism decompensation which promoted the fatal outcome of the affection.     

Chromatin and epigenetics in all their states: Meeting report of the first conference on Epigenetic and Chromatin Regulation of Plant Traits - January 14 – 15, 2016 - Strasbourg,France

In January 2016, the first Epigenetic and Chromatin Regulation of Plant Traits conference was held in Strasbourg, France. An all-star lineup of speakers, a packed audience of 130 participants from over 20 countries, and a friendly scientific atmosphere contributed to make this conference a meeting to remember. In this article we summarize some of the new insights into chromatin, epigenetics, and epigenomics research and highlight nascent ideas and emerging concepts in this exciting area of research.     

Endonuclease activity in the blood serum of rats undergoing nonuniform gamma irradiation

During the first hours following nonuniform gamma-irradiation (the nonuniformity coefficient was 3:1 and 5:1 with a dose change along the axis directed cranio-caudally and caudo-cranially), endonuclease activity (pH 5.75) in the blood serum increased with the dose which was estimated with a reference to total utilization of the substrate. Supercoiled plasmid DNA served as the substrate. The transformation of a supercoiled form of plasmid DNA into an open circular form was the criterion of estimation of nuclease activity. It was shown that the increase in the nuclease activity correlated with the increase in the nonuniformity coefficient.     

Structural changes in the DNA of the blood nucleotides and the development of late sequelae in irradiated rats

Fluorescent analysis of structural changes of nucleotide in the blood associated with AT fragments has been studied in rats, gamma-irradiated with doses of 2 and 4 Gy. It was demonstrated that the haematological, gerontological and cancerogenic late consequences were preceded by the structural genomic disturbances determined by 30 day after irradiation.