external irradiation
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2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Alexis Rump ◽  
Stefan Eder ◽  
Cornelius Hermann ◽  
Andreas Lamkowski ◽  
Patrick Ostheim ◽  
...  

AbstractIn the case of a terrorist attack by a “dirty bomb”, blast injuries, external irradiation and the incorporation of radioactivity are to be expected. Departing from information about the radiological attack scenario with cesium-137 in the U.S. National Scenario Planning Guide, we estimated the radiological doses absorbed. Similar calculations were performed for a smaller plume size and a detonation in a subway. For conditions as described in the U.S. scenario, the committed effective dose amounted to a maximum of 848 mSv, even for very unfavorable conditions. Red bone marrow equivalent doses are insufficient to induce acute radiation sickness (ARS). In the case of a smaller plume size, the ARS threshold may be exceeded in some cases. In a subway bombing, doses are much higher and the occurrence of ARS should be expected. The health hazards from a dirty bomb attack will depend on the location and the explosive device. The derived Haddon matrix indicates that preparing for such an event includes education of all the medical staff about radiation effects, the time lines of radiation damages and the treatment priorities. Further determinants of the outcome include rapid evacuation even from difficult locations, the availability of a specific triage tool to rapidly identify victims at risk for ARS, the availability of an antidote stockpile and dedicated hospital beds to treat seriously irradiated victims.


Author(s):  
I. Barillot ◽  
D. Azria ◽  
A. Lisbona ◽  
M.-A. Mahé

Author(s):  
S. Schumann ◽  
H. Scherthan ◽  
K. Pfestroff ◽  
S. Schoof ◽  
A. Pfestroff ◽  
...  

Abstract Aim The aim of this study was to provide a systematic approach to characterize DNA damage induction and repair in isolated peripheral blood mononuclear cells (PBMCs) after internal ex vivo irradiation with [131I]NaI. In this approach, we tried to mimic ex vivo the irradiation of patient blood in the first hours after radioiodine therapy. Material and methods Blood of 33 patients of two centres was collected immediately before radioiodine therapy of differentiated thyroid cancer (DTC) and split into two samples. One sample served as non-irradiated control. The second sample was exposed to ionizing radiation by adding 1 ml of [131I]NaI solution to 7 ml of blood, followed by incubation at 37 °C for 1 h. PBMCs of both samples were isolated, split in three parts each and (i) fixed in 70% ethanol and stored at − 20 °C directly (0 h) after irradiation, (ii) after 4 h and (iii) 24 h after irradiation and culture in RPMI medium. After immunofluorescence staining microscopically visible co-localizing γ-H2AX + 53BP1 foci were scored in 100 cells per sample as biomarkers for radiation-induced double-strand breaks (DSBs). Results Thirty-two of 33 blood samples could be analysed. The mean absorbed dose to the blood in all irradiated samples was 50.1 ± 2.3 mGy. For all time points (0 h, 4 h, 24 h), the average number of γ-H2AX + 53BP1 foci per cell was significantly different when compared to baseline and the other time points. The average number of radiation-induced foci (RIF) per cell after irradiation was 0.72 ± 0.16 at t = 0 h, 0.26 ± 0.09 at t = 4 h and 0.04 ± 0.09 at t = 24 h. A monoexponential fit of the mean values of the three time points provided a decay rate of 0.25 ± 0.05 h−1, which is in good agreement with data obtained from external irradiation with γ- or X-rays. Conclusion This study provides novel data about the ex vivo DSB repair in internally irradiated PBMCs of patients before radionuclide therapy. Our findings show, in a large patient sample, that efficient repair occurs after internal irradiation with 50 mGy absorbed dose, and that the induction and repair rate after 131I exposure is comparable to that of external irradiation with γ- or X-rays.


Cancers ◽  
2021 ◽  
Vol 13 (22) ◽  
pp. 5595
Author(s):  
Treewut Rassamegevanon ◽  
Louis Feindt ◽  
Lydia Koi ◽  
Johannes Müller ◽  
Robert Freudenberg ◽  
...  

Combination treatment of molecular targeted and external radiotherapy is a promising strategy and was shown to improve local tumor control in a HNSCC xenograft model. To enhance the therapeutic value of this approach, this study investigated the underlying molecular response. Subcutaneous HNSCC FaDuDD xenografts were treated with single or combination therapy (X-ray: 0, 2, 4 Gy; anti-EGFR antibody (Cetuximab) (un-)labeled with Yttrium-90 (90Y)). Tumors were excised 24 h post respective treatment. Residual DNA double strand breaks (DSB), mRNA expression of DNA damage response related genes, immunoblotting, tumor histology, and immunohistological staining were analyzed. An increase in number and complexity of residual DNA DSB was observed in FaDuDD tumors exposed to the combination treatment of external irradiation and 90Y-Cetuximab relative to controls. The increase was observed in a low oxygenated area, suggesting the expansion of DNA DSB damages. Upregulation of genes encoding p21cip1/waf1 (CDKN1A) and GADD45α (GADD45A) was determined in the combination treatment group, and immunoblotting as well as immunohistochemistry confirmed the upregulation of p21cip1/waf1. The increase in residual γH2AX foci leads to the blockage of cell cycle transition and subsequently to cell death, which could be observed in the upregulation of p21cip1/waf1 expression and an elevated number of cleaved caspase-3 positive cells. Overall, a complex interplay between DNA damage repair and programmed cell death accounts for the potential benefit of the combination therapy using 90Y-Cetuximab and external radiotherapy.


2021 ◽  
Vol 162 (37) ◽  
pp. 1471-1479
Author(s):  
Örs Ferenczi ◽  
Tibor Major ◽  
Zoltán Takácsi-Nagy

Összefoglaló. A szájüregi daganatok kuratív kezelésében az elsődlegesen választandó műtét mellett a sugárterápiának is jelentős szerepe van. A lokális tumormentesség biztosításához azonban dóziseszkaláció szükséges. Ennek külső besugárzással való megvalósítása a környező normálszövetek fölösleges dózisterhelésével és az ebből következő mellékhatások előfordulásának emelkedésével jár. A brachytherapia (BT) – amelynek során radioaktív sugárforrást/sugárforrásokat juttatunk a tumorba vagy annak közelébe – lehetővé teszi a helyileg magasabb dózis leadását a környező ép szövetek kímélésével. A BT a korai, T1–2N0 stádiumú szájüregi tumoroknál – kedvező prognosztikai faktorok mellett – akár kizárólagosan vagy mint posztoperatíve egyedül alkalmazott terápiás modalitás jön szóba. Kedvezőtlenebb prognózis esetén vagy előrehaladottabb stádiumban (T3–4 vagy N+) a műtétet és/vagy a percutan irradiációt kiegészítő eljárásként alkalmazható kedvező sugárfizikai tulajdonságai miatt. A kis dózisteljesítményű (low-dose-rate, LDR) BT-t már évtizedek óta alkalmazzák a terápiában, de ezt kezdi kiszorítani a nagy dózisteljesítményű (high-dose-rate, HDR), illetve a pulzáló dózisteljesítményű (pulse-dose-rate, PDR) BT. A jelen áttekintő tanulmány célja irodalmi adatok alapján a BT szerepének és indikációjának ismertetése a szájüregi daganatok kuratív kezelésében, alrégiókra lebontva. Orv Hetil. 2021; 162(37): 1471–1479. Summary. Radiation therapy plays a significant role in the curative treatment of oral cavity tumors, in addition to the primary choice of surgery. However, dose escalation is required to ensure local tumor control. Its implementation with external irradiation is accompanied by an unnecessary dose exposure to the surrounding normal tissues and an increase in the incidence of consequent side effects. Brachytherapy (BT), in which a radiation source/sources is/are placed inside or close to the tumor, allows a higher dose to be delivered locally, sparing the surrounding intact tissues. In addition to favorable prognostic factors in early T1–2N0 stage oral cavity tumors, BT is considered either exclusively or as a sole postoperative therapeutic modality. At less favorable prognosis or at a more advanced stage (T3–4 or N+), BT can be used as a complementary procedure after surgery and/or percutaneous irradiation based on its favorable radio-physical properties. Low-dose-rate (LDR) BT has been used in the therapy for decades, but recently it has been replaced by high-dose-rate (HDR) and pulse-dose-rate (PDR) BT. The purpose of this review is to describe the role and indications of BT in the treatment of oral cavity tumors categorized into subregions, based on the literature data. Orv Hetil. 2021; 162(37): 1471–1479.


2021 ◽  
pp. 48-54
Author(s):  
B. L. Djafarova

The paper is devoted to questions on optimum development of complex for control and evaluation of contamination of water basins used for collection of industrial waste water. The purpose of the paper is development of scientific-methodical basics for development of measuring system for control and evaluation of contamination of natural water basins with heavy metals using method of attenuation of irradiation of dissolved organic matters excited by external irradiation. The task on optimization of operational regime of measuring complex for control and evaluation of contamination of natural water basins by waste water of large scale point type polluter of environment with heavy metals. The known model of Shtern-Volmer is used as a basis which assumes non-linear relationship between formed complex and fluorescent irradiations attenuation degree. It is noted that potential possibilities of Shtern-Volmers model are used not fully till now. So that in known researches the water objects polluted by several same sources are mainly researched. It is shown that Shtern-Volmer model is also applicable for analysis and estimation of pollution of water basins by single strong polluter that is mining and processing plants. For analysis the suggested special parameter, inversely proportional to concentration of heavy metals in water is used. Integration of this parameter on all possible values of heavy metals concentration and imposition of special limitation condition on the searched for function of dependence of attenuated part of fluorescent irradiation on maximum concentration of heavy metals make it possible to formulate and solve the task on searching of optimum type of this function providing for the optimum regime of operation of the complex.


Author(s):  
D. S. Isubakova ◽  
O. S. Tsymbal ◽  
E. V. Bronikovskaya ◽  
N. V. Litviakov ◽  
I. V. Milto ◽  
...  

2021 ◽  
Vol 66 (3) ◽  
pp. 13-18
Author(s):  
Nelya Metlyaeva ◽  
M. Lartsev ◽  
A. Bushmanov ◽  
I. Galstyan ◽  
L. Ryabinina ◽  
...  

Purpose: To evaluate in dynamics the psychophysiological adaptation of a patient who received local radiation damage to the tissues of the left half of the chest IV (extremely severe) severity (23 years of observation). Material and methods: Patient KTS, 66 years old, as the main diagnosis are the effects of local radiation damage to the skin and underlying tissues of the left half of the chest from external radiation (about 3 % of body surface area) IV extremely severe. Before receiving a radiation injury, she was able-bodied and socially adapted, worked as a nurse. In 1996, she was diagnosed with stage I left breast cancer T1N0M0 stage I, in connection with which she underwent a sectoral resection of the mammary gland. Then the patient underwent a course of radiation therapy. By retrospective assessment, the total dose of therapeutic effect before the incident was 10 Gy. At the time of the next session of radiation therapy in connection with the breakdown of the apparatus, a sharp uncontrolled increase in the dose of ionizing radiation (more than 100 Gy) occurred, causing serious injury. The patient was admitted to the Institute of Biophysics Clinic on the 5th day. Psychophysiological research was carried out with the use of automated software and methodic complex «Expert», designed to study the personal characteristics of a person, cognitive and intellectual personality characteristics in 2001 – 2017 years. Results: The effects of local radiation damage to the skin and underlying tissues of the left half of the chest from external irradiation of IV (extremely severe) degree in the form of cicatricial-atrophic changes of the soft tissues, with no bone skeleton remain. Disorders of mental adaptation are expressed in the form of senesto-hypochondria disorders, autism of perception, demonstrativeness, apathetic depression and introversion. The most profound contribution to the reduction of the adaptation of the victim is brought about by the features of deep internal disharmony caused by contradictory combinations of demonstrativeness, schizoid traits, anxious depression and affective rigidity. Conclusion: The data obtained indicate that impaired mental adaptation is an integral part of the clinical picture of local radiation injuries, and reveal the urgent need not only of specific treatment of radiation injury, but also of psychotropic pharmacotherapy and psychotherapy.


2021 ◽  
Vol 17 (2) ◽  
pp. 114-124
Author(s):  
Y.V. Marushko ◽  
O.V. Khomych ◽  
T.V. Hyshchak ◽  
O.L. Tarynska ◽  
G.O. Shchegel

Relevance. Pneumonia is an actual problem of practical medicine. Diagnosis of pneumonia is quite complex and requires a comprehensive study, taking into account both clinical symptoms and the results of paraclinical research methods. Objective. The aim of the work is to generalize the data of the literature and our own experience of modern radiological and acoustic methods of pneumonia diagnosis. Methods. Analysis of scientific publications in the international electronic scientometric databases Scopus, PubMed by keywords. Search depth – 15 years (2007-2021). Results. The article summarizes its own data and presents a scientific review of the medical literature, which is devoted to the analysis of the problem of diagnosing pneumonia at different stages of treatment. Indications and contraindications to use, advantages and disadvantages of X-ray method, CT method and ultrasound diagnostics are described. The characteristic of a new method of hardware diagnostics which without external irradiation gives the chance to carry out primary acoustic remote diagnostics of pneumonia is resulted. Conclusion. Today there is a wide range of instrumental methods of studying the respiratory system that allow accurate diagnosis, but have some limitations in use in clinical practice, in particular in pediatrics. Promising is the development of new acoustic methods that have high diagnostic value, lack of additional radiation and contraindications.


Author(s):  
An Aerts ◽  
Uta Eberlein ◽  
Sören Holm ◽  
Roland Hustinx ◽  
Mark Konijnenberg ◽  
...  

Executive SummaryWith an increasing variety of radiopharmaceuticals for diagnostic or therapeutic nuclear medicine as valuable diagnostic or treatment option, radiobiology plays an important role in supporting optimizations. This comprises particularly safety and efficacy of radionuclide therapies, specifically tailored to each patient. As absorbed dose rates and absorbed dose distributions in space and time are very different between external irradiation and systemic radionuclide exposure, distinct radiation-induced biological responses are expected in nuclear medicine, which need to be explored. This calls for a dedicated nuclear medicine radiobiology. Radiobiology findings and absorbed dose measurements will enable an improved estimation and prediction of efficacy and adverse effects. Moreover, a better understanding on the fundamental biological mechanisms underlying tumor and normal tissue responses will help to identify predictive and prognostic biomarkers as well as biomarkers for treatment follow-up. In addition, radiobiology can form the basis for the development of radiosensitizing strategies and radioprotectant agents. Thus, EANM believes that, beyond in vitro and preclinical evaluations, radiobiology will bring important added value to clinical studies and to clinical teams. Therefore, EANM strongly supports active collaboration between radiochemists, radiopharmacists, radiobiologists, medical physicists, and physicians to foster research toward precision nuclear medicine.


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