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Sanchez-Nieto B.,University of Santiago de Chile | Exposito M.R.,University of Seville | Terron J.A.,Hospital Universitario Virgen Macarena | Ghetti C.,Azienda Ospedaliero Universitaria | And 9 more authors.
IFMBE Proceedings | Year: 2013

Finding out the best treatment plan that could be designed for a specific patient could be a difficult task. Benefits on terms of better tumor coverage have to be balanced against the drawbacks of poorer organ at risk sparing in order to make the decision on the optimum treatment technique. A large variety of photon beam radiotherapy (RT) techniques are currently available. The relative merits of different 34 treatment modalities for a prostate cancer, using the same CT data set and contours, have been analyzed in terms of the area under the Uncomplicated Control Probability curve. IMRT forward techniques have resulted to be the best ranked treatment modalities. © 2013 Springer-Verlag. Source


Yamshanov V.A.,Russian Research Center for Radiology and Surgical Technology | Koshelevskii V.K.,Russian Academy of Sciences
Advances in Gerontology | Year: 2013

Circadian rhythms of background gamma radiation and the Ki indices of the geomagnetic field (GMF) in August-September 2008, January-February 2010, and March 2011 have been studied. It has been demonstrated that in the summer period, the maximum radiation and increase in GMF activity have been observed at about 15:00 LT. In winter these maximums are synchronously shifted to a later time. It is assumed that in response to the background radiation and as a consequence the formation of free radicals, the body generates its own free radicals for their neutralization, such as nitric oxide, which form due to the cleavage of blood neutrophils with a decrease in GMF activity. In turn, the nitric oxide level in the body is regulated by the formation of melatonin, which has a pronounced circadian rhythm. © 2013 Pleiades Publishing, Ltd. Source


Yamshanov V.A.,Russian Research Center for Radiology and Surgical Technology
Advances in Gerontology | Year: 2011

The main causes of morbidity and mortality among the elderly population are oncological and cardiovascular diseases. Those who avoid these diseases have a chance to live longer. The author suggests a hypothesis of one common factor, deviation from which leads to either oncological or cardiovascular diseases. This factor is the amount of nitric oxide (NO) produced in the organism. Excessive NO creates a risk of oncopathology, while the lack of NO may lead to cardiovascular diseases. The ability of the organism to utilize the excess NO depends on the geomagnetic activity (GMA) during the intrauterine period. The geomagnetic field affects people's health throughout their lives. NO is produced in the body in different ways and is, among other things, related to the destruction of blood neutrophils, which depends on the state of the geomagnetic field; the latter, in turn, is affected by solar magnetic activity. © Pleiades Publishing, Ltd., 2011. Source


Shevtsov M.A.,Russian Academy of Sciences | Galibin O.V.,Saint Petersburg State University | Yudintceva N.M.,Russian Academy of Sciences | Blinova M.I.,Russian Academy of Sciences | And 9 more authors.
Journal of Biomedical Materials Research - Part A | Year: 2014

Angio- and osteogenesis following the two-stage (TS) implantation of the skin- and bone-integrated pylon seeded with autologous fibroblasts was evaluated. Two consecutive animal substudies were undertaken: intramedullary subcutaneous implantation (15 rabbits) and a TS transcutaneous implantation (12 rabbits). We observed enhanced osseointegrative properties of the intramedullary porous component seeded with fibroblasts induced into osteoblast differentiation, as compared to the untreated porous titanium pylon. The three-phase scintigraphy and subsequent histological analysis showed that the level of osteogenesis was 1.5-fold higher than in the control group, and significantly so (p < 0.05). The biocompatibility was further proved by the absence of inflammatory response or encapsulation and sequestration on the histology assay. Treatment of the transcutaneous component with autologous fibroblasts was associated with nearly a 2-fold decrease in the period required for the ingrowth of dermal and subdermal soft tissues into the implant surface, as compared to the untreated porous titanium component. Direct dermal attachment to the transcutaneous implant prevented superficial and deep periprosthetic infections in rabbits in vivo. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 3033-3048, 2014. © 2013 Wiley Periodicals, Inc. Source


Romero-Exposito M.,University of Seville | Romero-Exposito M.,Autonomous University of Barcelona | Sanchez-Nieto B.,University of Santiago de Chile | Terron J.A.,Hospital Universitario Virgen Macarena | And 10 more authors.
Medical Physics | Year: 2015

Purpose: Knowing the contribution of neutron to collateral effects in treatments is both a complex and a mandatory task. This work aims to present an operative procedure for neutron estimates in any facility using a neutron digital detector.Methods: The authors previous work established a linear relationship between the total second cancer risk due to neutrons (TRn) and the number of MU of the treatment. Given that the digital detector also presents linearity with MU, its response can be used to determine the TRn per unit MU, denoted as m, normally ssociated to a generic Linac model and radiotherapy facility. Thus, from the number of MU of each patient treatment, the associated risk can be estimated. The feasibility of the procedure was tested by applying it in eight facilities; patients were evaluated as well. ©2015 Am. Assoc. Phys. Med.Results: From the reading of the detector under selected irradiation conditions, m values were obtained for different machines, ranging from 0.25×l10-4% per MU for an Elekta Axesse at 10 MV to 6.5×10-4% per MU for a Varian Clinac at 18 MV. Using these values, TRn of patients was estimated in each facility and compared to that from the individual evaluation. Differences were within the range of uncertainty of the authors methodology of equivalent dose and risk estimations.Conclusions: The procedure presented here allows an easy estimation of the second cancer risk due to neutrons for any patient, given the number of MU of the treatment. It will enable the consideration of this information when selecting the optimal treatment for a patient by its implementation in the treatment planning system. © 2015 American Association of Physicists in Medicine Source

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