33 research outputs found

    Peculiarities of the technogenical radionuclides transfer from soils into plants in the radioactive contaminated areas

    No full text
    The peculiarities of 90Sr, 137Cs, 239,240Pu accumulation by some species of herbaceous plants in radioactive contaminated areas of nuclear enterprises in Russia have been investigated. Gas and aerosol discharge from Beloyarskaya NPP (which operates for more than 30 years) did not make considerable contamination of soil-vegetational cover in the 30-km zone. In close proximity to the epicenter of nuclear accident of 1957 in the Urals the concentration of the main contaminant (90Sr) in the plants reached maximal value (tens and hundred of thousands of Bq kgdw-1 depending on species belonging of plant). The concentration of 90Sr in aboveground phytomass of plants growing within floodplain of the Techa river ecosystems is thousands of Bq kgdw-1; at the same time, the 137Cs concentration is units of Bq kgdw-1. The absence of direct dependence between the radionuclides content in the soils and their concentration in aboveground phytomass is noticeable. The values of the radionuclides transfer coefficients in the plants were estimated as well as the content in the soils of their water-soluble and firmly fixed physic-chemical forms. The radionuclides have been ranked into a row according to their mobility in observed soils and biogeocenotical soil-plant link

    Nuclear nanomedicine using Si nanoparticles as safe and effective carriers of 188Re radionuclide for cancer therapy

    No full text
    International audienceNuclear nanomedicine, with its targeting ability and heavily loading capacity, along with its enhanced retention to avoid rapid clearance as faced with molecular radiopharmaceuticals, provides unique opportunities to treat tumors and metastasis. Despite these promises, this field has seen limited activities, primarily because of a lack of suitable nanocarriers, which are safe, excretable and have favorable pharmacokinetics to efficiently deliver and retain radionuclides in a tumor. Here, we introduce biodegradable laser-synthesized Si nanoparticles having round shape, controllable low-dispersion size, and being free of any toxic impurities, as highly suitable carriers of therapeutic 188 Re radionuclide. the conjugation of the polyethylene glycol-coated Si nanoparticles with radioactive 188 Re takes merely 1 hour, compared to its half-life of 17 hours. When intravenously administered in a Wistar rat model, the conjugates demonstrate free circulation in the blood stream to reach all organs and target tumors, which is radically in contrast with that of the 188 Re salt that mostly accumulates in the thyroid gland. We also show that the nanoparticles ensure excellent retention of 188 Re in tumor, not possible with the salt, which enables one to maximize the therapeutic effect, as well as exhibit a complete time-delayed conjugate bioelimination. Finally, our tests on rat survival demonstrate excellent therapeutic effect (72% survival compared to 0% of the control group). Combined with a series of imaging and therapeutic functionalities based on unique intrinsic properties of Si nanoparticles, the proposed biodegradable complex promises a major advancement in nuclear nanomedicine

    538umb_Brown.qxd

    No full text
    Abstract Leber's hereditary optic neuropathy (LHON) is characterized by maternally transmitted, bilateral, central vision loss in young adults. It is caused by mutations in the mitochondrial DNA (mtDNA) encoded genes that contribute polypeptides to NADH dehydrogenase or complex I. Four mtDNA variants, the nucleotide pair (np) 3460A, 11778A, 14484C, and 14459A mutations, are known as "primary" LHON mutations and are found in most, but not all, of the LHON families reported to date. Here, we report the extensive genetic and biochemical analysis of five Russian families from the Novosibirsk region of Siberia manifesting maternally transmitted optic atrophy consistent with LHON. Three of the five families harbor known LHON primary mutations. Complete sequence analysis of proband mtDNA in the other two families has revealed novel complex I mutations at nps 3635A and 4640C, respectively. These mutations are homoplasmic and have not been reported in the literature. Biochemical analysis of complex I in patient lymphoblasts and transmitochondrial cybrids demonstrated a respiration defect with complex-I-linked substrates, although the specific activity of complex I was not reduced. Overall, our data suggests that the spectrum of mtDNA mutations associated with LHON in Russia is similar to that in Europe and North America and that the np 3635A and 4640C mutations may be additional mtDNA complex I mutations contributing to LHON expression

    SYNTHESIS AND PROPERTIES OF BISMUTH-CONTAINING COMPOUNDS WITH SCHEELITE STRUCTURE BASED ON CaMoO4 AND SrMoO4

    Full text link
    The work is devoted to the study of synthesis processes, the boundaries of the region of existence and the study of solid solutions of strontium molybdate SrMoO4 and calcium mo-lybdate CaMoO4, monosubstituted with bismuth or disubstituted with bismuth and vanadium
    corecore