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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


Sanchez-Nieto B.,University of Santiago de Chile | Exposito M.R.,University of Seville | Terron J.A.,Hospital Universitario Virgen Macarena | Paiusco M.,Arcispedale S. Maria Nuova | And 12 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.


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.


Klimovich A.V.,Saint Petersburg State University | Samoylovich M.P.,Russian Research Center for Radiology and Surgical Technology | Gryazeva I.V.,Russian Research Center for Radiology and Surgical Technology | Terekhina L.A.,Russian Research Center for Radiology and Surgical Technology | And 2 more authors.
Helicobacter | Year: 2010

Background: Helicobacter pylori strains expressing cytotoxic CagA protein are more likely to provoke severe gastric mucosal pathology and cause adenocarcinoma development than that lacking CagA. Determination of the CagA-status of a pathogen, therefore, is regarded as informative approach in H. pylori infection diagnostics and disease risk prediction. Materials and Methods: Molecular cloning, recombinant protein expression in Escherichia coli, affinity chromatography, electrophoresis and commonly used techniques of hybridoma production and screening were used as well as different immunosorbent assays and Western blot procedures. Results: Four overlapping N-terminally His 6-tagged recombinant fragments of CagA that covered the entire CagA sequence were produced and purified. An ELISA for specific anti-CagA serum antibodies detection was developed and evaluated. Utilizing recombinant fragments, the first set of monoclonal antibodies against CagA-antigen was produced and characterized. Three antibodies recognized distinct linear epitopes inside conserved regions of the cytotoxin whereas the epitope of the forth antibody was mapped in the variable area of CagA. The monoclonal antibodies allowed discriminating CagA-positive and CagA-negative H. pylori strains by means of Western blot and immunosorbent assays. Conclusions: The use of recombinant protein technology allowed obtaining pure CagA antigen, thus providing new perspectives for development of immunodiagnostic reagents. The set of monoclonal antibodies is a valuable tool for determination of CagA-status of H. pylori infection and for the investigation of cytotoxin molecule as well. © 2010 Blackwell Publishing Ltd.


Samoylovich M.P.,Russian Research Center for Radiology and Surgical Technology | Griazeva I.V.,Russian Research Center for Radiology and Surgical Technology | Mazing A.V.,St. Petersburg State Medical University | Lapin S.V.,St. Petersburg State Medical University | Klimovich V.B.,Russian Research Center for Radiology and Surgical Technology
Medical Immunology (Russia) | Year: 2016

Detection of total free light chains (FLC) of immunoglobulins and their ratio (kappa/lambda quotient) are used in diagnostics and monitoring of multiple myeloma and other gammapathies, primary amyloidosis and multiple sclerosis. Previously described immunoassays with monoclonal antibodies (Mabs) against cryptic and constantly exposed epitopes of FLC failed to recognize rare variants of lambda Bence-Jones proteins and a significant proportion of lambda chains excreted with urine. Aiming to improve this approach, a novel murine Mab (IgG2b coded as 1C8) was employed, which specifically binds free lambda chains but doesn't interact with native IgA, IgG, and IgM. The novel Mab recognized an epitope exposed at free lambda chains in peripheral blood of healthy donors and patients with multiple myeloma. It is not destroyed or masked upon renal filtration. The aim of this study was to determine basic features of improved assay system, and to estimate its potential in diagnostics of monoclonal gammapathies. The mixtures of three Bence-Jones proteins of either kappa- or lambda-Types purified from the urine of multiple myeloma patients were used as calibrator samples. Improved immunometric assay is able to detect free kappa and lambda chains in serum and urine at a scale of 1 to 100 ng/ml, thus being three orders more sensitive than, e.g., detection levels of Freelite method based on polyclonal antibodies. A novel assay allows to detect free kappa and lambda chains at comparable levels in serum or urine, and to deduce kappa/lambda ratio. The proposed assay is able to detect FLC in 10,000-fold excess of whole IgG molecules. The calibrating plots for both antigens are linear on log-log scales, with very similar slopes. Detection thresholds for kappa or lambda chains proved to be 5 and 3 ng/ml, respectively. Mean concentrations of free kappa chains in sera of healthy donors were 6.7±2.1, in urine, 4.2±3.8 mcg/ml. Mean concentrations of free lambda chains were 4.7±1.96, and 1.6±1.0 mcg/ml, respectively. This method, if applied to serum and urine samples from multiple myeloma patients, revealed free light chains were similar to the paraproteins detected by means of electrophoresis/immunofixation. The values of kappa/lambda ratios corresponded to the types of gammapathies revealed. © 2016, SPb RAACI.


Sommer F.,University of Kiel | Sommer F.,Alfred Wegener Institute for Polar and Marine Research | Awazu S.,Sars International Center for Marine Molecular Biology | Anton-Erxleben F.,University of Kiel | And 11 more authors.
Molecular Biology and Evolution | Year: 2012

Adaptive immune systems are present only in vertebrates. How do all the remaining animals withstand continuous attacks of permanently evolving pathogens? Even in the absence of adaptive immunity, every organism must be able to unambiguously distinguish self cells from any imaginable nonself. Here, we analyzed the function of highly polymorphic gene vCRL1, which is expressed in follicle and blood cells of Ciona intestinalis, pointing to possible recognition roles either during fertilization or in immune reactions. By using segregation analysis, we demonstrate that vCRL1 locus is not involved in the control of self-sterility. Interestingly, genetic knockdown of vCRL1 in all tissues or specifically in hemocytes results in a drastic developmental arrest during metamorphosis exactly when blood system formation in Ciona normally occurs. Our data demonstrate that vCRL1 gene might be essential for the establishment of a functional blood system in Ciona. Presumably, presence of the vCRL1 receptor on the surface of blood cells renders them as self, whereas any cell lacking it is referred to as nonself and will be consequently destroyed. We propose that individual-specific receptor vCRL1 might be utilized to facilitate somatic self/nonself discrimination. © 2012 The Author.


Bespalov V.G.,N N Petrov Research Institute Of Oncology | Aleksandrov V.A.,N N Petrov Research Institute Of Oncology | Semenov A.L.,Russian Research Center for Radiology and Surgical Technology | Kovanko E.G.,The Surgical Center | Ivanov S.D.,The Surgical Center
Voprosy Onkologii | Year: 2012

Influence of bioginseng (biotechnological pharmaceutical drug from ginseng radix culture) on radiation-induced carcinogenesis has been studied. LIO female rats were divided into 3 groups. Rats of the first group (n=25) were used as intact control and weren't exposed to any influence. Rats of the second (n=50) and third (n=50) groups were exposed to single total body y-irradiation at a dose of 4 Gy. Animals of the 2 nd group weren't exposed to any influence after irradiation, while animals of the 3 rd group were given bioginseng with tap water (20 ml/l) until the end of study (438 days). In the control group 22,7% of animals developed tumors. In the 2 nd group (irradiated control) 70% of animals were bearing multiple tumors one third of which were malignant. Mammary gland tumors were most frequent. Compared to the 2 nd group the 3 rd group receiving irradiation and bioginseng demonstrated the decrease in tumor incidence by 24.5% and 2,4 rate of decrease in tumors number. For the malign tumors was observed the decrease by 26.8% and 2,9 times, accordingly. For the mammary tumors the decrease was by 23.0% and 2,0 times, for mammary adenocarcinomas by 23.4% and 3,5 times, accordingly. The incidence and number of endocrine and reproductive organs tumors was 20,9% and 5,6 times, accordingly. Therefore, bioginseng effectively inhibits carcinogenesis induced by ionizing radiation in female rats.


Vorobtsova I.E.,Russian Research Center for Radiology and Surgical Technology | Semenov A.V.,Russian Research Center for Radiology and Surgical Technology
Biophysics | Year: 2010

The frequency of translocations detected by FISH in lymphocytes of control donors increases with age as a quadratic function. This process is faster in persons previously exposed to low doses of radiation. It means that translocation frequency can be used as a measure of biological age. Moreover, translocation frequency should be taken into account in biological reconstruction of absorbed doses. The frequencies of dicentrics detected by FIGH and FPG linearly increase with age in both groups, and this process occurs at equal rates during natural and radiation-induced aging. The age-dependent increase in the frequency of translocations exceeds the increase in dicentrics. The radiation sensitivity of lymphocytes estimated from the frequency of in vitro induced chromosomal aberrations tends to increase with age in the control group and decreases significantly in the group exposed to radiation; i. e., low-dose preexposure alters the pattern of the age dependence of radiation sensitivity in lymphocytes in vitro. © 2010 Pleiades Publishing, Ltd.


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.


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.

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