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Spasojevic-Tisma V.D.,Public Company Nuclear Facilities of Serbia | Celeketic D.C.,Zemun Medical Center | Tisma J.M.,University of Belgrade | Milacic S.B.,Institute of Occupational Health | Papovic-Dukic G.V.,Health Center Vrbas
Nuclear Technology and Radiation Protection | Year: 2011

The study included 75 subjects exposed to low doses of external ionizing radiation and 25 subjects from the control group, all male. The first group (A) consisted of 25 subjects employed in the production of technetium, with an average job experience of 15 years. The second group (B) consisted of 25 subjects exposed to ionizing radiation from enclosed sources, working in jobs involving the control of X-ray devices and americium smoke detectors, their average work experience being 18.5 years. The third group (C) consisted of 25 subjects involved in the decontamination of the terrain at Borovac from radioactive rounds with depleted uranium left over after the NATO bombing of Serbia in 1999, their average job experience being 18.5 years. The control group (K) consisted of 25 subjects who have not been in contact with sources of ionizing radiation and who hold administrative positions. Frequencies of chromosome aberrations were determined in lymphocytes of peripheral blood and compared to the control group. The average annual absorbed dose determined by thermoluminescent dosimeters for all three groups did not exceed 2 mSv. In the present study, the largest number of observed changes are acentric fragments and chromosome breaks. The highest occupational risk appears to involve subjects working in manufacturing of the radioisotope technetium.

Manic V.,University of Nis | Manic G.,Institute of Occupational Health | Nikezic D.,University of Kragujevac | Krstic D.,University of Kragujevac
Radiation Protection Dosimetry | Year: 2012

The absorbed gamma dose rate in indoor air due to natural radionuclides in concrete as a building material was determined in this work. The dose rate conversion factors for 238U, 232Th and 40K, for standard rooms as well as rooms with different sets of dimensions, were evaluated by the point kernel technique, using Harima (geometric progression) build-up factors. The values of the conversion factors, in units (nGy h-1 (Bq kg. -1)-1) calculated for the standard room are: 0.76, 0.91 and 0.070, respectively for 238U, 232Th and 40K. The fitting formula was obtained for dose rate conversion factors, enabling them to be conveniently calculated for a room with arbitrary dimensions. For concrete block samples collected in the area of Niš, Serbia, the measurement of the radionuclide activity concentrations was also carried out. The evaluated absorbed dose rate conversion factors were then applied in the assessment of corresponding indoor gamma dose rates, finding that all the concrete samples fulfilled the usage requirement. © The Author 2012. Published by Oxford University Press. All rights reserved.

Raskovic A.,University of Novi Sad | Pavlovic N.,University of Novi Sad | Kvrgic M.,Pharmacy Novi Sad | Sudji J.,Institute of Occupational Health | And 3 more authors.
BMC Complementary and Alternative Medicine | Year: 2015

Background: Herbal supplements are widely used in the treatment of various liver disases, but some of them may also induce liver injuries. Regarding the infuence of thyme and its constituents on the liver, conflicting results have been reported in the literature. The objective of this study was to examine the influence of two commonly used pharmaceutical formulations containing thyme (Thymus vulgaris L.), tincture and syrup, on carbon tetrachloride-induced acute liver injury in rats. Methods: Chemical composition of investigated formulations of thyme was determined by gas chromatography and mass spectrometry. Activities of enzyme markers of hepatocellular damage in serum and antioxidant enzymes in the liver homogenates were measured using the kinetic spectrophotometric methods. Liver morphology was characterized by light microscopy using routine hematoxylin and eosin staining. Results: Thymol was found to be predominant active constituent in both tincture and syrup. Investigated thyme preparations exerted antioxidant effects in liver by preventing carbon tetrachloride-induced increase of lipid peroxidation. Furthermore, co-treatment with thyme preparations reversed the activities of oxidative stress-related enzymes xanthine oxidase, catalase, peroxidase, glutathione peroxidase and glutathione reductase, towards normal values in the liver. Hepatotoxicity induced by carbon tetrachloride was reflected by a marked elevation of AST and ALT activities, and histopathologic alterations. Co-administration of thyme tincture resulted in unexpected exacerbation of AST and ALT values in serum, while thyme syrup managed to reduce activites of aminotransferases, in comparison to carbon tetrachloride-treated animals. Conclusions: Despite demonstrated antioxidant activity, mediated through both direct free radical scavenging and activation of antioxidant defense mechanisms, thyme preparations could not ameliorate liver injury in rats. Molecular mechanisms of diverse effects of thyme preparations on chemical-induced hepatotoxicity should be more in-depth investigated. © 2015 Rašković et al.

Work equipment and installations with a high risk for health and safety of employees should be paid a special attention. The German Product Safety Act, which is aimed to manufacturers or distributors in order to protect consumers, maintains a conclusive catalogue of these so-called "installations in need of monitoring" fixing the work equipment and installations for which such special inspections can be demanded. This catalogue has remained unchanged for decades and has been transformed nearly unmodified into the Plant Safety Ordinance. Currently, there is a discussion about this catalogue in Germany. A major point of concern is the definition and the significance of "especially" dangerous work equipment and installations. Two recent research projects are dealing with the problem how to define "especially". © 2012 - IOS Press and the authors. All rights reserved.

Manic V.,University of Nis | Nikezic D.,University of Kragujevac | Krstic D.,University of Kragujevac | Manic G.,Institute of Occupational Health
Radiation Protection Dosimetry | Year: 2014

The specific absorbed gamma dose rates, originating from natural radionuclides in concrete, were calculated at different positions of a detection point inside the standard room, as well as inside an example room. The specific absorbed dose rates corresponding to a wall with arbitrary dimensions and thickness were also evaluated, and appropriate fitting functions were developed, enabling dose rate calculation for most realistic rooms. In order to make calculation simpler, the expressions fitting the exposure build-up factors for whole 238U and 232Th radionuclide series and 40K were derived in this work, as well as the specific absorbed dose rates from a point source in concrete. Calculated values of the specific absorbed dose rates at the centre point of the standard room for 238U, 232Th and 40K are in the ranges of previously obtained data. © The Author 2014. Published by Oxford University Press. All rights reserved.

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