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61.
I. Winkelmann G. N. Romanov P. Goloshapov P. Gesewsky S. Mundigl H. Buchröder M. Thomas C. Brummer W. Burkart 《Radiation and environmental biophysics》1998,37(1):57-61
A region between Chelyabinsk and Ekaterinburg in the Southern Urals has been heavily contaminated due to operational and
accidental releases from the first Soviet plutonium production facility Mayak. In 1992 and 1993, the German Federal Office
for Radiation Protection organized a measuring campaign involving two Russian institutes to assist with the validation of
former Soviet measurement data. The results of this measuring campaign are reported here. Environmental samples were collected
from areas affected by significant radioactive releases into the Techa river, which started in 1948, and by fallout from the
explosion of a fission product storage tank in 1957. Soil, sediment, water, milk and food samples were independently analysed
for 90Sr, 137Cs and plutonium by the three institutes involved. This paper presents data on the present levels of environmental radioactivity.
The highest contamination of areas accessible to the local population was found in the vicinity of the Techa river around
Muslumovo. Activity concentration of floodplain samples reached up to 37 000 Bq ⋅ kg–1 137Cs, 5 600 Bq ⋅ kg–1 90Sr and 9.9 Bq ⋅ kg–1 Pu. Milk and potatoes from private farms in Muslumovo showed low activity in the range from 0.7 Bq ⋅ kg–1 to 25 Bq ⋅ kg–1 90Sr. The results of the three independent measurement teams showed sufficient agreement. One Russian laboratory obtained plutonium
activities that exceeded the results of the other laboratories by about 20%. Contrary to the International Chernobyl Project,
there was no overestimation of 90Sr activities in the Russian analyses. Therefore, the validity of earlier data sets acquired with same methodology and quality
control can be considered a valuable basis for further assessments and for dose reconstruction in epidemiological projects.
Received: 18 July 1997 / Accepted in revised form: 19 December 1997 相似文献
62.
K. V. Chekashkina T. R. Galimzyanov P. I. Kuzmin S. A. Akimov S. A. Romanov G. E. Pozmogova D. V. Klinov P. V. Bashkirov 《Biochemistry (Moscow) Supplemental Series A: Membrane and Cell Biology》2017,11(3):217-224
Investigation of the transport phenomena in the nanoscopic channels/pores with the diameter smaller than 100 nm is of utmost importance for various biological, medical, and technical applications. Presently, the main line of development of nanofluidics is creation of biosensors capable of detecting single molecules and manipulating them. Detection of molecules is based on the measurement of electric current through a channel of appropriate size: when the molecule enters the channel, which diameter is comparable with the molecule size, the ion current reduces. In order to improve transport properties of such channels, their walls are often coated with a lipid bilayer, which behaves as two-dimensional liquid and thus is capable of supporting transport phenomena. In the present work, we utilized this property of lipid membranes for the development of a method for detecting and controlling transport of single-stranded DNA through channels formed by membrane cylinders with the luminal radii of 5–7 nm. We have demonstrated that in the conditions of small ion strength, the appearance of a DNA molecule inside such channel is accompanied by an increase of its ion conductivity and can be controlled by the polarity of the applied voltage. The amplitude of the ion current increase allows evaluating the amount of DNA molecules inside the channels. It was also demonstrated that upon adsorption of DNA molecules on the lipid bilayer surface, the membrane cylinder behaves as a voltage-sensitive selective ion channel. 相似文献
63.
Nikonov BI Gurvich VB Smirnova SS Romanenko VV Romanov SV 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》2008,(2):85-88
Materials on organizational support of preventive and antiepidemic measures during outbreak of Legionnaires' disease in town Verkhnyaya Pyshma (Sverdlovsk region) in July-August 2007 are presented. Thanks to collaborative efforts of Federal Service for Surveillance for Protection of Consumers Rights and Human Welfare, Ministry of Health of Sverdlovsk region, health-care services in Verkhnyaya Pyshma, near located municipalities, and others it was able to establish in short term the hospital for treatment, identify source of the infection and factor of its transmission, and terminate the outbreak. Operative implementation of the mentioned measures both allowed to provide good quality medical care to all patients and to prevent occurrence of such situations on other towns of Sverdlovsk region. 相似文献
64.
R. A. Romanov N. V. Kabanova S. L. Malkin S. S. Kolesnikov 《Biochemistry (Moscow) Supplemental Series A: Membrane and Cell Biology》2009,3(1):71-80
In cells of different types outward voltage-gated (VG) ion currents are generally carried by potassium ions. However, in mouse type II taste cells these currents persist when K+-selective ion channels are inhibited. In this study, we examined the ion channels that provide a pathway for atypical VG outward currents in type II taste cells. These channels are found to be weakly selective and permeabile to large molecules such as NMDG, gluconate, and ATP. According to non-stationary fluctuation analysis, single channel conductance is about 200 pS. The data obtained suggest that the nonselective ion channels are similar to hemichannels formed by connexins, the gap-junction proteins, in the plasma membrane of vertebrate cells. 相似文献
65.
Taxonomic composition and structure of the phytoplankton were studied in the lowland rivers of the upper Ob basin: Barnaulka, Bol’shaya Losikha, and lower Inya. It has been shown that the phytoplankton of a large river system in Eurasia, exemplified by the Ob basin, is characterized by spatial heterogeneity in its taxonomic composition. 相似文献
66.
O. A. Antonova S. A. Loktionova Yu. A. Romanov O. N. Shustova M. V. Khachikian A. V. Mazurov 《Biochemistry. Biokhimii?a》2009,74(6):605-612
Disturbances of blood flow upon vascular occlusions and spasms result in hypoxia and acidosis, while its subsequent restoration leads to reoxygenation and pH normalization (re-alkalization) in ischemic sites of the vascular bed. The effect of hypoxia/reoxygenation on activation and stimulation of apoptosis in cultured human endothelial cells was studied. The cells were subjected to hypoxia (2% O2, 5% CO2, 93% N2) for 24 h followed by reoxygenation (21% O2, 5% CO2, 74% N2) for 5 h. Reoxygenation was carried out at different pH-6.4 (preservation of acidosis after hypoxia), 7.0, and 7.4 (partial and complete re-alkalization, respectively). Hypoxia only slightly (by ~30%) increased the cell adhesion molecule ICAM-1 content on the cell surface, whereas reoxygenation more than doubled its expression. The reoxygenation effect depended on the medium acidity, and ICAM-1 increase was more pronounced at pH 7.0 compared to that at pH 6.4 and 7.4. Neither hypoxia nor reoxygenation induced expression of two other cell adhesion molecules, VCAM and E-selectin. Incubation of cells under hypoxic conditions but not reoxygenation stimulated secretion of von Willebrand factor and increased its concentration in the culture medium by more than 4 times. The percentage of cells containing apoptosis marker, activated caspase-3, was increased by approximately 1.5 times upon hypoxia as well as hypoxia/reoxygenation. Maximal values were achieved when reoxygenation was performed at pH 7.0. These data show that hypoxia/reoxygenation stimulate pro-inflammatory activation (ICAM-1 expression) and apoptosis (caspase-3 activation) of endothelial cells, and the extracellular pH influences both processes. 相似文献
67.
Romanov A. N. Kovrigin A. O. Grigoruk O. G. Lubennikov V. A. Lazarev A. F. 《Biophysics》2011,56(4):709-716
The dielectric parameters of ascitic and pleural fluids formed in the human body in oncological and nononcological diseases
of different nosology have been estimated in the range between 400 MHz and 1.2 GHZ. The dependence of refractive and absorption
indices of ascitic and pleural liquids on the signal frequency and mass concentration of dissolved substances was found. Common
regularities and distinctions in the behavior of their dielectric properties were revealed. 相似文献
68.
Wulfetange K Lomin SN Romanov GA Stolz A Heyl A Schmülling T 《Plant physiology》2011,156(4):1808-1818
The plant hormone cytokinin is perceived by membrane-located sensor histidine kinases. Arabidopsis (Arabidopsis thaliana) possesses three cytokinin receptors: ARABIDOPSIS HISTIDINE KINASE2 (AHK2), AHK3, and CYTOKININ RESPONSE1/AHK4. The current model predicts perception of the cytokinin signal at the plasma membrane. However, cytokinin-binding studies with membrane fractions separated by two-phase partitioning showed that in the wild type, as well as in mutants retaining only single cytokinin receptors, the major part of specific cytokinin binding was associated with endomembranes. Leaf epidermal cells of tobacco (Nicotiana benthamiana) expressing receptor-green fluorescent protein fusion proteins and bimolecular fluorescence complementation analysis showed strong fluorescence of the endoplasmic reticulum (ER) network for all three receptors. Furthermore, separation of the microsomal fraction of Arabidopsis plants expressing Myc-tagged AHK2 and AHK3 receptors by sucrose gradient centrifugation followed by immunoblotting displayed the Mg2?-dependent density shift typical of ER membrane proteins. Cytokinin-binding assays, fluorescent fusion proteins, and biochemical fractionation all showed that the large majority of cytokinin receptors are localized to the ER, suggesting a central role of this compartment in cytokinin signaling. A modified model for cytokinin signaling is proposed. 相似文献
69.
Population genetics successfully applies surnames as quasi-genetic markers when estimating similarity between populations
and calculating the level of random inbreeding. These calculations are based on the isonymy coefficient, which assumes that
every surname is monophyletic, i.e., it originated from a single common ancestor and all namesakes are therefore relatives.
On the other hand, there is a general opinion that a typical Russian surname is polyphyletic: it originated multiple times
and most namesakes are, therefore, not related to each other. Combined studies of Y chromosomes and surnames now allow us
to address this issue. This study discusses approaches to statistical evaluation of Y chromosome haplogroup frequencies in
groups of people bearing the same surname (namesakes). The proposed index of accumulated haplogroup frequency eliminates the
artifactual effect of a randomly increased haplogroup frequency in namesakes by subtracting its population (expected) frequency
from the observed value, while the expected frequency is calculated as the weighted average of the frequencies of this haplogroup
in the populations where the surname carriers come from. From the total sample (comprising 1244 persons from 13 populations
of the historical Russian area), 123 individuals carrying 14 most frequent surnames were chosen. A comparison of the haplogroup
frequencies in these 14 namesake groups and in 14 respective population control groups compiled from the total sample showed
that accumulation of certain Y chromosome haplogroups was nonrandom even in carriers of widespread surnames. An analysis of
Y-STR haplotypes rather than Y-SNP haplogroups could provide a better insight into relationships between namesakes and will
be the subject of further research. 相似文献
70.
Michael N Romanov Marta Farré Pamela E Lithgow Katie E Fowler Benjamin M Skinner Rebecca O’Connor Gothami Fonseka Niclas Backstr?m Yoichi Matsuda Chizuko Nishida Peter Houde Erich D Jarvis Hans Ellegren David W Burt Denis M Larkin Darren K Griffin 《BMC genomics》2014,15(1)