scholarly journals EANM position paper on the role of radiobiology in nuclear medicine

2021 ◽  
Author(s):  
An Aerts ◽  
Uta Eberlein ◽  
Sören Holm ◽  
Roland Hustinx ◽  
Mark Konijnenberg ◽  
...  
Keyword(s):  
Nuclear Medicine ◽  
Absorbed Dose ◽  
Added Value ◽  
External Irradiation ◽  
Executive Summary ◽  
Dose Rates ◽  
Biological Responses ◽  
Medical Physicists ◽  
Radiation Induced

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.

Radiation-induced color centers in LiF for dosimetry at high absorbed dose rates

1980 ◽  
Vol 175 (1) ◽  
pp. 17-18 ◽  
Author(s):  
William L. McLaughlin ◽  
Arne Miller ◽  
Stuart C. Ellis ◽  
Arthur C. Lucas ◽  
Barbara M. Kapsar
Keyword(s):  
Absorbed Dose ◽  
Color Centers ◽  
Dose Rates ◽  
Radiation Induced ◽  
Absorbed Dose Rates

Radiation Biomarkers : Applications in Triage Management of Radiation Victims

2017 ◽  
Vol 2 (3) ◽  
pp. 270
Author(s):  
Saurabh Mishra ◽  
Raj Kumar
Keyword(s):  
Ionizing Radiation ◽  
Absorbed Dose ◽  
Physiological Status ◽  
Scenario Development ◽  
Potential Health ◽  
Biological Responses ◽  
Gene And Protein Expression ◽  
Genetic Perturbations ◽  
Biologic Response ◽  
Radiation Induced

Human exposure to ionizing radiation disrupts normal metabolic processes in cells and organs by inducing complex biological responses that interfere with gene and protein expression. Conventional dosimetry, monitoring of prodromal symptoms and peripheral lymphocyte counts are of limited value as organ- and tissue-specific biomarkers for personnel exposed to radiation, particularly, weeks or months after exposure. Analysis of metabolites generated in known stress-responsive pathways by molecular profiling helps to predict the physiological status of an individual in response to environmental or genetic perturbations. There is a need for research to rapidly determine an individual’s absorbed dose and its potential health effects after a potential radiological or nuclear event that could expose large portions of a population to ionizing radiation. Studies on biomarker identification after radiation exposure could contribute in biodosimetry, identifying individual dose absorbed, as well as biologic response, and administering immediate and proper medical care. In the recent scenario development of biomarker is major thrust area. In the present review paper articles related to gene biomarker, protein biomarker and metabolic biomarker are reviewed in order to sketch an overview on the recent advances related to developing an biomarker to assess the radiation induced toxicity.

Radiation induced chromosome aberrations in human foetal cells grown in vitro

1962 ◽  
Vol 11 (4) ◽  
pp. 356-389 ◽  
Author(s):  
J. A. Böök ◽  
M. Fraccaro ◽  
K. Fredga ◽  
J. Lindsten
Keyword(s):  
Brain Tissue ◽  
Cell Cultures ◽  
Lung Tissue ◽  
Cultured Cells ◽  
Absorbed Dose ◽  
Cell Populations ◽  
Foetal Brain ◽  
Radiation Induced ◽  
Foetal Lung

SUMMARYThe effect of ionizing radiation, from a 100 Curie Cobalt-60 source, on diploid human cells grown in vitro has been investigated.The analysed cell populations originated from foetal brain and lung tissue. Other known variations of this material were age and sex of the foetuses, primary and first transfer cultures.The effect was measured by recording post-metaphase chromosomal aberrations in cell cultures fixed and stained 24 and 48 hours after acute irradiation. “Spontaneous” aberration frequencies were determined in matched control cultures.Although conclusions must be guarded, in view of the insufficient knowledge of factors influencing human cell populations in vitro, our observations can be summarized, tentatively, in the following main points.1. The frequency of “spontaneous” aberrations appears to vary with respect to (a) differences between the individuals from whom the biopsies were taken, (b) tissue of origin whether within or between individuals and (c) the sex of the cultured cells.The qualified estimates of the overall averages of “spontaneous” aberrations were, (a) for the cell cultures derived from foetal lung 0.7 per cent (41/5,891 scored cells) and (b) for the cell cultures derived from foetal brain 2.5 per cent (21/851 scored cells).2. In the irradiated cell cultures which received doses varying from 9-136 rads of absorbed dose the number of aberrant post-metaphases per 100 cells per rad varied from 0.10-0.15 for cultures derived from lung tissue and from 0.19-0.37 for cultures derived from brain tissue, all at 24 hours after the acute dose. At 48 hours after irradiation the frequencies were somewhat lower but the same trends remained.3. The cell cultures derived from brain tissue appear to have a higher radio-sensitivity than those derived from lung tissue. Furthermore, a sexual dimorphism is suggested because, in all series of cultures, those composed of XY cells had a higher aberration frequency as compared to those with XX cells.4. The irradiation doubling dose (for definition, see p. 27) was estimated at 15-40 rads (cf. table 7).

CONSTRUCTION AND VALIDATION OF IN VITRO DOSE–RESPONSE CALIBRATION CURVE USING DICENTRIC CHROMOSOME ABERRATION

2020 ◽  
Vol 189 (2) ◽  
pp. 198-204
Author(s):  
Ehsan Mirrezaei ◽  
Saeed Setayeshi ◽  
Farideh Zakeri ◽  
Samaneh Baradaran
Keyword(s):  
Dose Response ◽  
Calibration Curve ◽  
Radiation Effects ◽  
Standard Dose ◽  
Absorbed Dose ◽  
Dicentric Chromosome ◽  
Blood Samples ◽  
Radiation Induced ◽  
Occupational Radiation

Abstract Cytogenetic biodosimetry is a well-known method for quantifying the absorbed dose based on measuring biological radiation effects. To correlate the induced chromosomal abberrations with the absorbed dose of the individuals, a reliable dose–response calibration curve should be established. This study aimed to use frequencies and distributions of radiation-induced dicentric chromosome aberrations to develop a standard dose–response calibration curve. Peripheral blood samples taken from six male donors irradiated by an X-ray generator up to 4 Gy were studied. Three different blood samples were irradiated by known doses, then scored blindly for verification of the proposed calibration curve. Dose estimation was also carried out for three real overexposed cases. The results showed good accordance with the other published curves. The constructed dose–response curve provides a reliable tool for biological dosimetry in accidental or occupational radiation exposures.

Absorbed-Dose Specification in Nuclear Medicine: Abstract

2002 ◽  
Vol 2 (1) ◽  
pp. 9-9 ◽  
Author(s):  
S. J. Adelstein ◽  
A. J. Green ◽  
R. W. Howell ◽  
J. L. Humm ◽  
P. K. Leichner ◽  
...  
Keyword(s):  
Nuclear Medicine ◽  
Absorbed Dose ◽  
The Body ◽  
Patient Specific ◽  
Dose Rates ◽  
Uniform Distributions ◽  
Medical Internal Radiation Dose ◽  
Medical Dosimetry ◽  
Dose Responses ◽  
Selection Of

A number of reasons have led to a reappraisal of dose specification for nuclear medicine. These include an appreciation of non-uniformities in the distribution of radioactivity in the body, at all levels, for even the most common diagnostic and therapeutic agents; an increasing need to deal with the complexities of varying dose rates; the imperative to provide individual rather than standardised dose estimates as targeted radionuclide therapy becomes more sophisticated; as well as improvements in technology. This Report deals first with biological considerations that inform the rational use of radionuclide dosimetry. Radiobiological factors in the selection of radionuclides and tumour and normal-tissue dose-responses are discussed. Then, the MIRD (medical internal radiation dose) approach to nuclear medical dosimetry, a robust method that has proven its clinical utility, is described. Following on is an elaboration of non-uniform distributions of radioactivity and of varying dose rates. Lastly, the Report deals with techniques and procedures for measuring time variant activity distributions, image fusion, patient specific dose computations, smallscale dosimetry, and the comparison of calculated and measured doses.

scholarly journals DNA damage and repair in peripheral blood mononuclear cells after internal ex vivo irradiation of patient blood with 131I

2021 ◽  
Author(s):  
S. Schumann ◽  
H. Scherthan ◽  
K. Pfestroff ◽  
S. Schoof ◽  
A. Pfestroff ◽  
...  
Keyword(s):  
Mononuclear Cells ◽  
Radioiodine Therapy ◽  
Ex Vivo ◽  
Absorbed Dose ◽  
External Irradiation ◽  
X Rays ◽  
Peripheral Blood Mononuclear ◽  
Time Points ◽  
Radiation Induced ◽  
The Mean

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.

Patients with fever of unknown origin (FUO): diagnosis by nuclear medicine imaging

2001 ◽  
Vol 40 (03) ◽  
pp. 59-70 ◽  
Author(s):  
W. Becker ◽  
J. Meiler
Keyword(s):  
Nuclear Medicine ◽  
Fever Of Unknown Origin ◽  
Tumor Imaging ◽  
White Blood Cells ◽  
Unknown Origin ◽  
Final Diagnosis ◽  
Recurrent Fever ◽  
Nuclear Medicine Imaging

SummaryFever of unknown origin (FUO) in immunocompetent and non neutropenic patients is defined as recurrent fever of 38,3° C or greater, lasting 2-3 weeks or longer, and undiagnosed after 1 week of appropriate evaluation. The underlying diseases of FUO are numerous and infection accounts for only 20-40% of them. The majority of FUO-patients have autoimmunity and collagen vascular disease and neoplasm, which are responsible for about 50-60% of all cases. In this respect FOU in its classical definition is clearly separated from postoperative and neutropenic fever where inflammation and infection are more common. Although methods that use in-vitro or in-vivo labeled white blood cells (WBCs) have a high diagnostic accuracy in the detection and exclusion of granulocytic pathology, they are only of limited value in FUO-patients in establishing the final diagnosis due to the low prevalence of purulent processes in this collective. WBCs are more suited in evaluation of the focus in occult sepsis. Ga-67 citrate is the only commercially available gamma emitter which images acute, chronic, granulomatous and autoimmune inflammation and also various malignant diseases. Therefore Ga-67 citrate is currently considered to be the tracer of choice in the diagnostic work-up of FUO. The number of Ga-67-scans contributing to the final diagnosis was found to be higher outside Germany than it has been reported for labeled WBCs. F-l 8-2’-deoxy-2-fluoro-D-glucose (FDG) has been used extensively for tumor imaging with PET. Inflammatory processes accumulate the tracer by similar mechanisms. First results of FDG imaging demonstrated, that FDG may be superior to other nuclear medicine imaging modalities which may be explained by the preferable tracer kinetics of the small F-l 8-FDG molecule and by a better spatial resolution of coincidence imaging in comparison to a conventional gamma camera.

Radiation exposure in the environment of patients after application of radiopharmaceuticals

2008 ◽  
Vol 47 (06) ◽  
pp. 267-274 ◽  
Author(s):  
F. Boldt ◽  
C. Kobe ◽  
W. Eschner ◽  
H. Schicha ◽  
F. Sudbrock
Keyword(s):  
Nuclear Medicine ◽  
Radiation Exposure ◽  
Radioactive Source ◽  
Time Intervals ◽  
The Public ◽  
Dose Rates ◽  
Diagnostic Nuclear Medicine ◽  
Photon Dose ◽  
Order Of Magnitude ◽  
Study Dose

Summary Aim: After application of radiopharmaceuticals the patient becomes a radioactive source which leads to radiation exposure in the proximity. The photon dose rates after administration of different radiopharmaceuticals used in diagnostic nuclear medicine were measured at several distances and different time intervals. These data are of importance for estimating the exposure of technologists and members of the public. Patients, method: In this study dose rates were measured for 67 patients after application of the following radiopharmaceuticals: 99mTc-HDP as well as 99mTcpertechnetate, 18F-fluorodeoxyglucose, 111In-Octreotid and Zevalin® and 123I-mIBG in addition to 123I-NaI. The dose rates were measured immediately following application at six different distances to the patient. After two hours the measurements were repeated and – whenever possible – after 24 hours and seven days. Results: Immediately following application the highest dose rates were below 1 mSv / h: with a maximum at 780 μSv/h for 18F (370 MBq), 250 μSv/h for 99mTc (700 MBq), 150 μSv/h for 111In (185 MBq) and 132 μSv/ h for 123I (370 MBq). At a distance of 0.5 m the values decrease significantly by an order of magnitude. Two hours after application the values are diminished to 1/3 (99mTc, 18F), to nearly ½ (123I) but remain in the same order of magnitude for the longer-lived 111In radiopharmaceuticals. Conclusion: For greater distances the doses remain below the limits outlined in the national legislation.

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