Biodosimetry of Persons Chronically Exposed to Low and Therapeutic Doses of Ionizing Radiation.

Dynamic changes of the chromosomal aberrations and the DNA damage were analyzed in individuals exposed to low and therapeutic doses of radiation. The investigation included 37 persons living in areas where the radioactive sources were discovered 10-12 years ago. It was established by biodosimetry methods that the examined persons had absorbed dose of 0.

[Useage of genetic markers to determine the impact of radiation on the human body].

The timely determination of the fact of radiation impact on the organism is extremely important for preventive and curative interventions. Despite the fact that so far cytogenetic violations are considered to be the best biomarkers to determine the impact of ionizing radiation on the organism, actual problem is to find the optimal combination of different biomarkers. The aim of the work was investigation of the extended set of biomarkers in distant periods of exposure in people previously assigned to the radiation risk group, as well as the identification of genetic disorders in the process of radiotherapy.

Thermal analysis of whole bacterial cells exposed to potassium permanganate using differential scanning calorimetry: a biphasic dose-dependent response to stress.

The DSC technique applied to the study of the toxic impact of permanganate on bacterial cell culture detected the lack of linearity in the dose-response effect. The results were confirmed by the traditional assay of colony forming ability. The changed pattern of thermal spectra of A.

Effects of Cr(VI) long-term and low-dose action on mammalian antioxidant enzymes (an in vitro study).

In order to investigate the low-dose long-term Cr(VI) action on antioxidant enzymes in cultured mammalian cells we estimated the activity of glutathione dependent antioxidant enzymes, catalase and superoxide dismutase (SOD) under various chromium concentrations in human epithelial-like L-41 cells. The long-term action of 20 microM causes the toxicity that results in losing of the cell viability by activating the apoptotic process, as identified by morphological analysis, the activation of caspase-3, and DNA fragmentation. The toxic chromium concentration totally destroys glutathione antioxidant system, and diminishes the activity of catalase and cytosolic Cu, ZnSOD.

A calorimetric characterization of Cr(VI)-reducing Arthrobacter oxydans at different phases of the cell growth cycle.

This is the first of a series of calorimetric studies designed to characterize and understand survival mechanisms of metal-reducing bacteria isolated from metal-polluted environments. In this paper we introduce a new concept of thermal spectrum of the endothermic melting of complex biological systems (e.g.