Научно-практический опыт надзорной деятельности в области обеспечения защиты населения и окружающей среды на объектах ядерного наследия России

Today, Russia is implementing a national program for the remediation of legacy sites, resulting from the activities of the nuclear industry, the use of nuclear energy for military purposes, and due to radiation accidents and emergencies. Main priority is given to the health care provision issues of the workers and the population living in the vicinity of the targeted facilities. These tasks are under the regulatory responsibility of the FMBA of Russia. Since the beginning of the development of the nuclear industry in the country, the Institute of Biophysics, technical supporting organization of the FMBA of Russia (now the State Research Center – Burnasyan Federal Medical Biophysical Center Federal Medical Biological Agency (SRC-FMBC)), has been a leading institute in the scientific and methodological support of public radiation safety in the vicinity of radiation hazardous facilities serviced by the FMBA of Russia. In this regard, radiation-hygienic monitoring has always served as the main regulatory tool for more than 60 years. The paper describes the results of long-term monitoring (2005-2018) at the former coastal technical bases of the Russian Navy ( now – sites for temporary storage of SNF and RW in the Russian Northwest and Far East (nuclear legacy sites); sites of the uranium mining and milling facilities: Priargun Mountain Chemical Association and former Production Association “Almaz” (Lermontov, Stavropol Krai); and at uranium legacy sites of the Central Asia (Republic of Tajikistan and Kyrgyz Republic). The peculiarities of radiation situation at the sites are discussed, current challenges identified, and further regulatory improvements presented based on the gained experience.В настоящее время в России реализуется национальная программа реабилитации площадок наследия, образовавшихся в результате деятельности атомной промышленности, использования ядерной энергии в военных целях, а также вследствие радиационных аварий и инцидентов. В ходе ее выполнения приоритетное место уделяется вопросам медико-санитарного обеспечения персонала и населения, проживающего вблизи этих предприятий. Данная деятельность лежит в сфере полномочий Федерального медико-биологического агентства (ФМБА России). С самого начала становления атомной промышленности в нашей стране ведущим институтом по медицинским проблемам отрасли являлся Институт биофизики (ныне – ГНЦ ФМБЦ им. А.И. Бурназяна ФМБА России), являющийся технически поддерживающей организацией ФМБА России. Одним из основных направлений и главным назначением его деятельности является научно-методическое обеспечение радиационной безопасности и защиты персонала и населения, проживающего в районах расположения радиационных объектов. В этом крайне обширном направлении работ радиационно-гигиенический мониторинг на протяжении более 60 лет всегда занимал главенствующее место. В настоящей работе представлены результаты многолетнего радиационно-гигиенического мониторинга (2005–2018 гг.) на бывших береговых технических базах Военно-морского флота России, а ныне – пунктах временного хранения отработавшего ядерного топлива и радиоактивных отходов на Северо-Западе и на Дальнем Востоке России; территориях расположения объектов уранодобывающей и перерабатывающей промышленности: Приаргунское горно-химическое объединение (Забайкальский край) и бывшее производственное объединение «Алмаз» (г. Лермонтов, Ставропольский край); а также на объектах уранового наследия в Средней Азии (Республики Таджикистан и Кыргызстан). Обсуждены закономерности формирования радиационной обстановки в районах расположения объектов наследия, обозначены существующие проблемы и представлены дальнейшие направления совершенствования радиационной безопасности с учетом накопленного опыта

Радиационная обстановка на территории площадки уранового наследия в пади Бамбакай (Забайкальский край)

The article presents the results of a study of the current radiation situation at the uranium legacy site located in the territory of the Bambakai Valley (Transbaikal Territory), formed in the period from 1973 to 1989 due to the discharge of mine water. During the radiation survey, the method of pedestrian gamma survey was used to measure the ambient dose equivalent rate. Soil sampling was carried out to study the radionuclide specific activities in the soil. The activity of gamma-emitting radionuclides in the samples was measured with a stationary gamma spectrometer. The activities of 210Po and 210Pb were measured after their radiochemical extraction from samples. It was found that the values of ambient dose equivalent rate in the territory of the valley varied over the wide range from 0.1 to 1.4 µSv/h in the areas under manmade contamination. The estimated average value of the gamma background for this place is 0.14±0.02 µSv/h. The specific activities of 238U, 226Ra, 235U, 210Pb and 210Po in the surface 10-cm soil layer at the site are from 10-40 times higher than the background values. The most part of radionuclides in the soil is in the acid-soluble form. Effective doses of the workers involved in hay harvesting in the area of the fallow land do not exceed 1.5 µSv/year. Doses of terrestrial environmental media (grass, earthworms) are 100 and more times lower than the safe level of exposure to biota.В статье приводятся результаты исследования современной радиационной обстановки на площадке уранового наследия, расположенной на территории пади Бамбакай (Забайкальский край), образовавшейся в период с 1973 по 1989 г. из-за сброса шахтных вод. При радиационном обследовании для измерения мощности амбиентного эквивалента дозы использовался метод пешеходной гамма-съемки. Для исследования удельной активности радионуклидов в почве проводился отбор проб. Активность гамма-излучающих радионуклидов в пробах измерялась на стационарном гамма-спектрометре. Измерение активности 210Po и 210Pb проводилось после их радиохимического выделения из проб. Установлено, что значения мощности амбиентного эквивалента дозы на территории пади варьируются в широком диапазоне от 0,1 до 1,4 мкЗв/ч на участках с техногенным загрязнением. Оцененное среднее значение гамма-фона для данной местности составляет 0,14±0,02 мкЗв/ч. Удельная активность 238U, 226Ra, 235U, 210Pb и 210Po в поверхностном 10-сантиметровом слое почвы на локальных загрязненных участках территории в 10–40 раз выше фоновых значений. Большая часть радионуклидов в почве находится в кислоторастворимой форме. Эффективные дозы облучения работников, проводящих заготовку сена на территории пади, не превышают 1,5 мкЗв/год. Дозы облучения наземных биообъектов (трава, дождевые черви) ниже безопасного уровня облучения биоты в 100 и более раз

Scientific and practical experience of supervisory activities in the field of the public and environmental protection at the Russian nuclear legacy sites

Today, Russia is implementing a national program for the remediation of legacy sites, resulting from the activities of the nuclear industry, the use of nuclear energy for military purposes, and due to radiation accidents and emergencies. Main priority is given to the health care provision issues of the workers and the population living in the vicinity of the targeted facilities. These tasks are under the regulatory responsibility of the FMBA of Russia. Since the beginning of the development of the nuclear industry in the country, the Institute of Biophysics, technical supporting organization of the FMBA of Russia (now the State Research Center – Burnasyan Federal Medical Biophysical Center Federal Medical Biological Agency (SRC-FMBC)), has been a leading institute in the scientific and methodological support of public radiation safety in the vicinity of radiation hazardous facilities serviced by the FMBA of Russia. In this regard, radiation-hygienic monitoring has always served as the main regulatory tool for more than 60 years. The paper describes the results of long-term monitoring (2005-2018) at the former coastal technical bases of the Russian Navy ( now – sites for temporary storage of SNF and RW in the Russian Northwest and Far East (nuclear legacy sites); sites of the uranium mining and milling facilities: Priargun Mountain Chemical Association and former Production Association “Almaz” (Lermontov, Stavropol Krai); and at uranium legacy sites of the Central Asia (Republic of Tajikistan and Kyrgyz Republic). The peculiarities of radiation situation at the sites are discussed, current challenges identified, and further regulatory improvements presented based on the gained experience

Rab11 Is Required for Membrane Trafficking and Actomyosin Ring Constriction in Meiotic Cytokinesis of Drosophila Males

Rab11 is a small GTPase that regulates several aspects of vesicular trafficking. Here, we show that Rab11 accumulates at the cleavage furrow of Drosophila spermatocytes and that it is essential for cytokinesis. Mutant spermatocytes form regular actomyosin rings, but these rings fail to constrict to completion, leading to cytokinesis failures. rab11 spermatocytes also exhibit an abnormal accumulation of Golgi-derived vesicles at the telophase equator, suggesting a defect in membrane–vesicle fusion. These cytokinesis phenotypes are identical to those elicited by mutations in giotto (gio) and four wheel drive (fwd) that encode a phosphatidylinositol transfer protein and a phosphatidylinositol 4-kinase, respectively. Double mutant analysis and immunostaining for Gio and Rab11 indicated that gio, fwd, and rab11 function in the same cytokinetic pathway, with Gio and Fwd acting upstream of Rab11. We propose that Gio and Fwd mediate Rab11 recruitment at the cleavage furrow and that Rab11 facilitates targeted membrane delivery to the advancing furrow

Rho GTPases regulate PRK2/PKN2 to control entry into mitosis and exit from cytokinesis

Rho GTPases regulate multiple signal transduction pathways that influence many aspects of cell behaviour, including migration, morphology, polarity and cell cycle. Through their ability to control the assembly and organization of the actin and microtubule cytoskeletons, Rho and Cdc42 make several key contributions during the mitotic phase of the cell cycle, including spindle assembly, spindle positioning, cleavage furrow contraction and abscission. We now report that PRK2/PKN2, a Ser/Thr kinase and Rho/Rac effector protein, is an essential regulator of both entry into mitosis and exit from cytokinesis in HeLa S3 cells. PRK2 is required for abscission of the midbody at the end of the cell division cycle and for phosphorylation and activation of Cdc25B, the phosphatase required for activation of mitotic cyclin/Cdk1 complexes at the G2/M transition. This reveals an additional step in the mammalian cell cycle controlled by Rho GTPases

C. elegans RNA-dependent RNA polymerases rrf-1 and ego-1 silence Drosophila transgenes by differing mechanisms

Drosophila possesses the core gene silencing machinery but, like all insects, lacks the canonical RNA-dependent RNA polymerases (RdRps) that in C. elegans either trigger or enhance two major small RNA-dependent gene silencing pathways. Introduction of two different nematode RdRps into Drosophila showed them to be functional, resulting in differing silencing activities. While RRF-1 enhanced transitive dsRNA-dependent silencing, EGO-1 triggered dsRNA-independent silencing, specifically of transgenes. The strain w; da-Gal4; UAST-ego-1, constitutively expressing ego-1, is capable of silencing transgene including dsRNA hairpin upon a single cross, which created a powerful tool for research in Drosophila. In C. elegans, EGO-1 is involved in transcriptional gene silencing (TGS) of chromosome regions that are unpaired during meiosis. There was no opportunity for meiotic interactions involving EGO-1 in Drosophila that would explain the observed transgene silencing. Transgene DNA is, however, unpaired during the pairing of chromosomes in embryonic mitosis that is an unusual characteristic of Diptera, suggesting that in Drosophila, EGO-1 triggers transcriptional silencing of unpaired DNA during embryonic mitosis.Guowen Duan, Robert B. Saint, Chris A. Helliwell, Carolyn A. Behm, Ming-Bo Wang, Peter M. Waterhouse, Karl H. J. Gordo

A Molecular Probe for the Detection of Polar Lipids in Live Cells.

Lipids have an important role in many aspects of cell biology, including membrane architecture/compartment formation, intracellular traffic, signalling, hormone regulation, inflammation, energy storage and metabolism. Lipid biology is therefore integrally involved in major human diseases, including metabolic disorders, neurodegenerative diseases, obesity, heart disease, immune disorders and cancers, which commonly display altered lipid transport and metabolism. However, the investigation of these important cellular processes has been limited by the availability of specific tools to visualise lipids in live cells. Here we describe the potential for ReZolve-L1™ to localise to intracellular compartments containing polar lipids, such as for example sphingomyelin and phosphatidylethanolamine. In live Drosophila fat body tissue from third instar larvae, ReZolve-L1™ interacted mainly with lipid droplets, including the core region of these organelles. The presence of polar lipids in the core of these lipid droplets was confirmed by Raman mapping and while this was consistent with the distribution of ReZolve-L1™ it did not exclude that the molecular probe might be detecting other lipid species. In response to complete starvation conditions, ReZolve-L1™ was detected mainly in Atg8-GFP autophagic compartments, and showed reduced staining in the lipid droplets of fat body cells. The induction of autophagy by Tor inhibition also increased ReZolve-L1™ detection in autophagic compartments, whereas Atg9 knock down impaired autophagosome formation and altered the distribution of ReZolve-L1™. Finally, during Drosophila metamorphosis fat body tissues showed increased ReZolve-L1™ staining in autophagic compartments at two hours post puparium formation, when compared to earlier developmental time points. We concluded that ReZolve-L1™ is a new live cell imaging tool, which can be used as an imaging reagent for the detection of polar lipids in different intracellular compartments