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[en] It is conceivable, and possible, that with increasing applications of nuclear energy, greater quantities of potentially harmful radionuclides will be released to the environment. This may be particularly true for advanced reactor designs such as the fusion reactor where radionuclides, principally tritium, may be expected to escape from the plant both in gaseous and liquid effluents in quantities significantly greater than for present PWR or BWR designs. Foreseeing such contingencies, the research programs described herein are in response to the need to measure the potential radiation effects of tritium releases on individuals, and ultimately populations and biotic communities. As a first approach, our efforts are directed to determine effects of low-level chronic exposures on developing embryo and larval stages, clearly the most radiosensitive. The anticipated increase in the release of beryllium and lithium from mining, refining, and fabrication of materials used during construction of fusion reactors has also caused concern as to potential adverse effects on the environment. Accordingly, FY-78 fusion related research will include efforts to study the metabolism of each metal in the living organism, and to determine at what levels toxicity may be expected. Fusion related research will also include preliminary experiments on the effects of low-level magnetic fields. It is conceivable that magnetic fields of 70 to 450 gauss will be encountered by attendant personnel working in the transport and hot cell areas of fusion reactors. Also, those personnel assigned to the areas immediately surrounding the reactor may be exposed
[en] Highlights: • ‘Omic’ technologies are appropriate tools for radioecological research. • Systems biology methods can facilitate field radioecological studies. • Fast revealing of mode of action and adverse outcome pathways. - Abstract: This article presents a brief review of the modern ‘omic’ technologies, namely genomics, epigenomics, transcriptomics, proteomics, and metabolomics, as well as the examples of their possible use in radioecology. For each technology, a short description of advances, limitations, and instrumental applications is given. In addition, the review contains examples of successful use of ‘omic’ technologies in the assessment of biological effects of pollutants in the field conditions.
[en] Endothelial cells (EC) in tumor and normal tissue constitute critical radiotherapy targets. MicroRNAs have emerged as master switchers of the cellular transcriptome. Here, we seek to investigate the role of miRNAs in primary human dermal microvascular endothelial cells (HDMEC) after ionizing radiation. The microRNA status in HDMEC after 2 Gy radiation treatment was measured using oligo-microarrays covering 361 miRNAs. To functionally analyze the role of radiation-induced differentially regulated miRNAs, cells were transfected with miRNA precursor or inhibitor constructs. Clonogenic survival and proliferation assays were performed. Radiation up-regulated miRNA expression levels included let-7g, miR-16, miR-20a, miR-21 and miR-29c, while miR-18a, miR-125a, miR-127, miR-148b, miR-189 and miR-503 were down-regulated. We found that overexpression or inhibition of let-7g, miR-189, and miR-20a markedly influenced clonogenic survival and cell proliferation per se. Notably, the radiosensitivity of HDMEC was significantly influenced by differential expression of miR-125a, -127, -189, and let-7g. While miR-125a and miR-189 had a radioprotective effect, miR-127 and let-7g enhanced radiosensitivity in human endothelial cells. Our data show that ionizing radiation changes microRNA levels in human endothelial cells and, moreover, exerts biological effects on cell growth and clonogenicity as validated in functional assays. The data also suggest that the miRNAs which are differentially expressed after radiation modulate the intrinsic radiosensitivity of endothelial cells in subsequent irradiations. This indicates that miRNAs are part of the innate response mechanism of the endothelium to radiation
[en] Heparin causes a rise in free thyroxine (FT4) measured by equilibrium dialysis (E.D.). With the introduction of at least 4 commercial radioimmunoassays (RIA) for FT4, FT4 measurements have become accepted as one of the best routine thyroid function tests. Investigators have indicated that FT4 levels determined by RIA may be of particular value in patients hospitalized for various severe nonthyroidal illnesses in whom conventional thyroid function tests tend to be abnormal. However, very little information is as yet available on possible effects of various drugs on FT4 levels measured by these new methods. A study was undertaken to evaluate the effect of heparin on FT4 measured by 2 different RIA procedures: RIA-I, GammaCoat FT4 by clinical Assays and RIA-II, Amerlex FT4 by Amersham
[en] A retrospective of modern approaches to the synthesis of natural butano- and butenolides based on the use of recent achievements of synthetic organic chemistry is given. For most of the considered compounds, natural sources and biological activities are indicated.
[en] The effects of tritiated water on the development of P. luzonica were determined in terms of the histology of 5 veliger stages using 3 different tritium concentrations, namely, 3.7 Bq/ml, 3.7 x 102 Bq /ml and 3.7 x 104 Bq/ml. An HTO concentration of at least 3.7 x 102 Bq/ml brought about histological abnormalities in the digestive tract in the 5 veliger stages. The structure in the veliger most affected by HTO is the larval stomach. To a lesser degree, differences were found in the larval intestine and stomodaeum. (Auth.). 9 refs.; 10 figs
[en] Advanced Radiation Technology Institute is a government-supported institute for radiation research and application. It has focused on development of fundamentals for radiation applications based on the existing radiation technology, and on enhancement of biological effectiveness of radiation through theoretical approach to the combined actions of radiation with another factor. Application of radiation technology together with the existing technologies to enhance the physical, chemical, biological characteristics through modification of biomolecules resulted in creation of de novo materials of scientific and industrial values. A theoretical model for combined action of radiation with another physico-chemical factor has been established. Conclusively the results of this study can provide scientific bases for maximizing the efficacy of ionizing radiation in relation to industrial applications