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![Chemical and biological effects by ionizing radiation. On the left side: from physical interaction (a few milliseconds) to clinical effects (decades later). On the right side: the corresponding molecular (DNA damage), cellular (cell damage or proliferation), and clinical events (such as cancer). Redrawn and modified from ref. [10].](profile/Ilenia-Foffa/publication/26648377/figure/fig1/AS:201520726450180@1425057693326/Chemical-and-biological-effects-by-ionizing-radiation-On-the-left-side-from-physical.png)
Chemical and biological effects by ionizing radiation. On the left side: from physical interaction (a few milliseconds) to clinical effects (decades later). On the right side: the corresponding molecular (DNA damage), cellular (cell damage or proliferation), and clinical events (such as cancer). Redrawn and modified from ref. [10].
Source publication
Cardiac diagnostic or therapeutic testing is an essential tool for diagnosis and treatment of cardiovascular disease, but it also involves considerable exposure to ionizing radiation. Every exposure produces a corresponding increase in cancer risk, and risks are highest for radiation exposure during infancy and adolescence. Recent studies on chromo...
Context in source publication
Context 1
... the biological effects of a stochastic effect are at DNA level and they may not be detected. The basic concept is that physical steps that lead to energy deposition and free radical formation occur within 10 -5 to 10 -6 seconds, whereas the biological expression of physical damage may occur a second or decades later [10] (Figure 1). Radiation-induced mutation contribute to the multi-step process of human cancer arising from the accumulation of multiple genetic abnormalities (over-expression of genes, deletion of genes, or gene mutations), some of which must occur in critical genes that regulate proliferation and differentiation. ...Citations
... This radiation carries risks, categorized into deterministic effects, like skin issues and cataracts, and stochastic effects, increasing the likelihood of cancer with higher doses [2]. Workplace radiation exposure is limited to 20-50 millisieverts (mSv) per year [3]. ...
Background
Catheter laboratories are high-radiation exposure environments, especially during X-ray procedures like percutaneous transluminal coronary angioplasty and electrophysiological studies. Radiation exposure poses risks of stochastic (e.g., cancer) and deterministic (e.g., skin changes) effects. This study assessed radiation safety and health practices in a cardiac catheterization unit to optimize radiation safety. A cross-sectional study in Cairo University Hospital (March–September 2019) evaluated 700 patients and healthcare workers. Real-time radiation measurements, educational lectures, and radiation protection measures were implemented in three phases. Data on radiation exposure, procedures, and compliance were collected and analyzed.
Results
The total procedure time and fluoroscopy time per cardiologist did not significantly differ between phases, but there was a statistically significant reduction in the mean total cumulative radiation doses between Phase I and Phase III for cardiologists ( P = 0.013). Among nurses and technicians, there was no significant difference in radiation doses between the two phases. Significant correlations were found between operators' radiation doses, procedure time, and fluoroscopy time. Patients' radiation doses decreased significantly from Phase I to Phase III, with correlations between dose, procedure time, and gender. Compliance with radiation protection measures was suboptimal.
Conclusions
Compliance with radiation safety standards in the cardiac catheterization unit at the Cairo University Hospital needs improvement. The study highlights the importance of adhering to radiation safety principles and optimizing protective measures to reduce radiation exposure for both patients and healthcare personnel. Despite low compliance, significant reductions in radiation doses were achieved with increased awareness and adherence to specific protection measures. Future efforts should focus on enhancing radiation safety protocols and organ-specific radiation impact assessments.
... A mechanistic understanding, together with the identification of biomarkers for individuals at increased risk to develop adverse health effects, has the potential to increase the power of epidemiological studies regarding health effects caused by IR [16][17][18]. Such biomarkers may be useful in identifying susceptible individuals who are more vulnerable to radiation damage for whom individualized treatment can be considered (by radiation sparing policy or attempts to pharmacologic or dietary radioprotection). ...
... Over the recent years, there has been considerable technological advancements that improve the therapeutic gain of radiotherapy, i.e., maximizing the dose to the tumor while sparing the healthy tissue, [7,36], as well as implementing numerous dose reduction strategies in pediatric interventional cardiology [3,37]. The difficulties associated with cancer and non-cancer risk assessments from pediatric radiation exposure could be partly overcome with precise dose estimation and biochemical studies to better understand the mechanisms that underly the development of disease processes and provide indicators of risk [16][17][18]. ...
The Health Effects of Cardiac Fluoroscopy and Modern Radiotherapy (photon and proton) in Pediatrics (HARMONIC) is a five-year project funded by the European Commission that aimed to improve the understanding of the long-term ionizing radiation (IR) risks for pediatric patients. In this paper, we provide a detailed overview of the rationale, design, and methods for the biological aspect of the project with objectives to provide a mechanistic understanding of the molecular pathways involved in the IR response and to identify potential predictive biomarkers of individual response involved in long-term health risks. Biological samples will be collected at three time points: before the first exposure, at the end of the exposure, and one year after the exposure. The average whole-body dose, the dose to the target organ, and the dose to some important out-of-field organs will be estimated. State-of-the-art analytical methods will be used to assess the levels of a set of known biomarkers and also explore high-resolution approaches of proteomics and miRNA transcriptomes to provide an integrated assessment. By using bioinformatics and systems biology, biological pathways and novel pathways involved in the response to IR exposure will be deciphered.
... Medical X-ray is most common forms of radiation in medicine, and one of the largest manmade sources of radiation exposure to patients, radiology staff (workers), and the general populace, hence there exists the problem of safely delivering radiation dose when imaging biological tissues [1][2][3]. For example, conventional radiography accounts more than 80 % of X-ray-based imaging [4], and it is considered a responsible for the most of the radiation exposure associated with all medical imaging techniques [5]. ...
Water polluted by hazardousdyes such as congo red (CR) face challenges to the regulation of water supplies. In the laboratory scale experiment, we report the novel approach for the synthesis of Fe3O4/TG nanocomposite. The Fe3O4/TG nanocomposite was synthesized by co-precipitation method. The surface properties and chemical compositions have been investigated using Fourier transform infrared spectroscopy (FTIR), X- ray diffractometer (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM) instrumentation. The XRD study indicates that nanocomposite were formed in the nano-scale (11.5 nm) and this is in accordance with TEM results. The maximum removal of CR dye was recorded at 2.0 pH. Approximately, 89.51 % deterioration of congo red (CR) dye has been achieved within 250 min of solar exposure. The prepared Fe3O4/TG nanocomposite is found to efficient photocatalyst for the removal of noxious dye from waste water.
... Such metastable routes are not necessarily the same as the prompt (which in the context of our experiments means within several Figure 1.4: Times scales for radiation induced damage and respective stages. Adapted from[18]. ...
Understanding the radiation response of biological material on the nano-scale is a major goal in Chemical Physics. A valuable tool for identifying critical excitation processes and reactions is to compare studies of sequentially more complex molecular systems. However, as the system’s complexity increases, so does the number of different conformations within an experimental target -- notably different tautomers or cluster arrangements. This complicates experimental interpretations and analogies with biology. This thesis responds to this problem by investigating conformation-specific radiation-induced reactivity in gas-phase biomolecules and clusters.
Firstly, we probe the dissociative ionisation of guanine – the only DNA base with significant populations of multiple tautomers in the gas phase and one of the bases with lowest volatility.
We used a desorption method (indirect laser-induced thermal desorption, ILTD) that has recently been shown to be effective at producing intact targets of non-volatile molecules and carried out experiments to confirm the absence of thermal decomposition in our targets. The comparison of metastable dissociation experiments with DFT calculations reveals new evidence for tautomer-dependent fragmentation pathways. We have also extended this work to guanosine targets and investigated the contribution of its tautomers and conformers to the radiation response through
DFT and TDDFT calculations.
Secondly, this thesis demonstrates a new approach to trace radiation-induced reaction products to the respective neutral clusters precursors in Stark-deflected supersonic beams. Molecular and cluster ion signals produced by an electron beam crossing the central axis of a nitromethane-argon beam are recorded as a function of deflection voltage. Comparing the resultant Stark removal curves with simulations shows that the detected protonated nitromethane and nitromethane-CH3+ ions are reaction products from one specific dimer configuration. This success highlights the method’s great potential for elucidating precise intermolecular bonding effects in radiochemistry.
Furthermore, we report on the development of a new experiment to study low-energy electron interactions with Stark-deflected molecules and clusters, as well as with ILT-desorbed molecules.
... Significant polymorphism-specific repair defects for the in vitro X and gamma ray-induced DNA damage were observed by Au et al. (2003) and Godderis et al. (2006) especially OGG1 326 , XRCC1 Gln 399 , and XRCC3 Met 241 . Foffa et al. (2009) reported that individuals having two or more variant alleles of DNA repair genes and exposed to low-dose ionizing radiation were at increased risk of chromosomal DNA damage. ...
DNA damage may develop at any dose of ionizing radiation. DNA damage activates pathways that regulate cell growth and division or coordinate its replication and repair. The repair pathways, base excision repair (BER) and single-strand break repair (SSBR), can repair such damages efficiently and maintain genome integrity. Loss of this repair process or alteration of its control will be associated with serious outcomes for cells and individuals. This study aimed to determine the relationship between XRCC1 (Arg194Trp, Arg280His, and Arg399Gln), OGG1 (Ser326Cys), and XRCC3 (Thr241Met) SNPs and DNA damage and to identify high-risk individuals with reduced DNA repair capacity. This case-control study was conducted on 80 subjects; 50 subjects working in Clinical Oncology and Nuclear Medicine Department in Assiut University Hospital along with 30 controls. A total of 1 mL blood samples were collected for Single-Cell Gel Electrophoresis Technique (Comet Assay) for detection of DNA damage in those subjects. A total of 3 mL fresh blood samples were collected and analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP)–based technique. DNA damage detected by comet test was significantly high in IR-exposed workers than control. Statistically high significant difference was found in exposed subjects versus control subjects regarding the frequencies of the variant alleles of hOGG1326, XRCC1280 & 399, and XRCC3241. The level of DNA damage was not affected by OGG1326 SNPs when comparing subjects of wild genotype with those of (pooled) variants either in the exposed staff or in the control group while XRCC1280, 399 and XRCC3241 variant alleles had an influence on the studied DNA damage biomarker. Moreover, genotyping distribution pattern was highly variable in relation to gender. The present study indicated a relationship between DNA damage detected by comet test and single nucleotide polymorphisms in genes coding for DNA certain repair enzymes. Individuals occupationally exposed to low doses of ionizing radiation could be at great risk and more susceptible to the increased DNA damage if they have inherited genetic polymorphism.
... The probability of inducing the effect, but not the severity, will increase in relation to the dose and could be different between individuals. For example, a low dose of IR <50 mSv will not directly damage any organ in the body, but repeated exposures will increase cancer risk over the lifetime of the individual [8]. This risk can be mitigated by physicians ordering fewer unnecessary radiological examination procedures. ...
AIM: The purpose of the study was to evaluate the knowledge of referring physicians of general practitioners, residents, and medical specialists in Jordan and the Middle East on radiation dose and its impact on vulnerable patients. MATERIALS AND METHODS: The Institutional Review Board approved this study before data collection. A cross-sectional study employed questionnaire that was distributed to respondents (n = 293) of general practitioners, residents, specialists, and therapists. The questionnaire consisted of 29 questions. Nine questions concerned with demographics and the remaining 20 questions were divided into five sections: Radiation dose, ionizing radiation, pediatric radiation, pregnant women radiation, and radiation risks. The mean score was computed out of 20. Chi-squared test of independence was utilized to analyze each question. To compare the responses between the demographic variables groups, Kruskal–Wallis and Mann–Whitney tests were used. RESULTS: Out of the 293 respondents, 128 (43.7%) were aware of radiation. The average score of the questionnaire was 9.5 out of 20 (47.5%). Within each section, the level of knowledge varied. Physicians had the highest level of knowledge in radiation risk (85.7%) followed by ionizing radiation (62.1%). The questionnaire revealed lower levels of knowledge in the areas of pediatric radiation, pregnant women radiation, and radiation dose. The percentages of respondents, (with fair to good level of knowledge), were 47.1%, 34.5%, and 24.6%, respectively. CONCLUSION: The results of this study were consistent with previous studies that demonstrated a poor level of general knowledge in referring physicians regarding radiation dose, ionizing radiation, pediatric radiation, pregnant women radiation, and radiation risks.
... Depuis les phénomènes physiques (quelques picosecondes après l'irradiation) aux effets cliniques (plusieurs années après l'irradiation). Adaptée de (Foffa et al. 2009) et image de . ...
... Lors de la radiothérapie, les phénomènes induits sont d'abord physiques (de 10 -18 à 10 -12 seconde après irradiation), puis chimiques (de 10 -12 à 1 seconde après irradiation) et enfin biologiques ( Figure 3) (Singh et al. 1982;Foffa et al. 2009). ...
La radiothérapie est un traitement majeur dans la lutte contre le cancer, avec plus de 50% des patients atteints d’un cancer qui en bénéficie, et pouvant à elle seule conduire à une rémission complète. Bien que les avancées technologiques aient diminuées considérablement les effets secondaires, 5 à 15 % des patients traités par radiothérapie souffrent d’effets secondaires sévères au niveau des tissus sains, limitant ainsi l’application de ce traitement. Ces effets secondaires sévères sont variés dans leur forme (desquamation, nécrose, fibrose), dans leur intensité (certains peuvent conduire à une nouvelle hospitalisation) ainsi que dans leur temps d’apparition (de quelques jours à plusieurs années après la radiothérapie). L’apparition de ces effets secondaires sévères chez certains patients de radiothérapie alors que les protocoles sont standardisés met à jour l’existence d’une radiosensibilité propre à chacun : la radiosensibilité individuelle. Malheureusement, à ce jour, il n’existe pas de test clinique applicable en routine qui fasse consensus, permettant de mesurer la radiosensibilité individuelle des patients atteints d’un cancer afin d’individualiser les protocoles de radiothérapie. D’autre part, les mécanismes moléculaires conduisant à ces effets secondaires restent encore mal connus. Nous avons donc étudié le transcriptome et le méthylome de fibroblastes dermiques de patients ayant souffert d’effets secondaires sévères de radiothérapie afin d’identifier une signature de la radiosensibilité individuelle et également de mieux comprendre les bases moléculaires sous-jacentes. Nous avons ainsi observé dans une 1ère cohorte que les fibroblastes cutanés des patients radiosensibles présentaient un profil transcriptomique et méthylomique spécifique. A l’aide d’une approche de machine learning, nous avons pu mettre à jour, une signature composée de 5 gènes dont l’expression nous a permis d’identifier les patients ayant souffert d’effets secondaires de radiothérapie dans une 2ème cohorte indépendante. De plus, nous avons observé que les fibroblastes des patients ayant souffert d’effets secondaires de radiothérapie présentaient un défaut de réparation de l’ADN ainsi qu’une toxicité accrue après irradiation. Finalement, nous avons identifié le facteur de transcription NFATc2 comme un acteur de la réponse aux radiations ionisantes dont la déficience peut entraîner un défaut de réparation de l’ADN et augmenter la radiosensibilité cellulaire. Ce travail de thèse a donc permis de révéler une signature moléculaire des cellules de patients ayant souffert d’effets secondaires sévères de radiothérapie, une première étape vers la mise au point d’un nouveau test clinique, et ouvre la voie à une meilleure compréhension des mécanismes de la radiosensibilité individuelle
... Similar to other studies that evaluated the cancer risk associated with radiation, we observed a profound effect of sex and age in increasing the risk of cancer after radiation exposure. Researchers have discovered that age and sex differences in DNA damage and gene rearrangement or fusion associated with radiation exposure may contribute to the divergence (28)(29)(30). These sets of evidence support the development of radiation biomarkers potentially improving risk assessments of lowdose radiation exposure and increasing safety. ...
Background:
Worldwide use of computed tomography (CT) scans has increased. However, the ionizing radiation from CT scans may increase the risk of cancer. This study examined the association between medical radiation from CT scans and the risk of thyroid cancer, lymphoma, and non-Hodgkin lymphoma (NHL) in adults.
Methods:
We conducted a nested case-control study in a cohort constructed from a population-based universal health insurance dataset in Taiwan in 2000-2013. In total, 22 853 thyroid cancer, 13 040 leukemia, and 20 157 NHL cases with their matched controls were included. Median follow-up times were 9.29-9.90 years for the three case-control groups. Medical radiation from CT scans was identified through physician order codes in medical insurance data from the index date to 3 years before a cancer diagnosis. Conditional logistic regression modeling was used for the overall and subsets of the population defined by sex and age groups to estimate the odds ratio (OR) and 95% confidence interval (CI) of the cancer risk associated with medical radiation.
Results:
Exposure to medical radiation from CT scans was associated with elevated risk of thyroid cancer (OR = 2.55, 95% CI = 2.36 to 2.75) and leukemia (OR = 1.55, 95% CI = 1.42 to 1.68). The elevated risk of thyroid cancer and leukemia in association with medical CT was stronger in women than in men. No statistically significant association between the risk of cancer and CT scans was observed in overall patients with NHL (OR = 1.05, 95% CI = 0.98 to 1.12); however, increased risks were found in patients aged 45 years or younger. A clear dose-response relationship was observed in patients 45 years or younger for all three cancers.
Conclusions:
CT scans may be associated with an increased risk of thyroid cancer and leukemia in adults and in those diagnosed with NHL at a younger age.
... Radiation doses as low as 0.1-0.5 Gy represent the range that most of the population will receive during a lifetime, mainly due to medical exposures (e.g., from the increasing number of computerized tomography scans). Exposure to such doses does not cause immediate problems to any organ, and the risk is only observed over long periods of time after exposure (8). The effects can be more evident in those who were exposed as children, since younger populations are more radiosensitive and have a longer life expectancy beyond the time of exposure, thus making risk assessment more critical in childhood (9). ...
Nontargeted late effects of radiation include an increased risk of cardiovascular disease, although this is still debatable in the context of low-dose radiation. Tinea capitis patients treated in childhood with X rays to induce scalp epilation received a low dose of radiation to their carotids. To better clarify this issue, we evaluated carotid atherosclerosis in a cohort of such patients treated in 1950-1963 in Portugal. A group of 454 individuals randomly chosen from previously observed Portuguese tinea capitis patients and a control group mainly composed of their spouses (n = 280) were enrolled. Cardiovascular risk factors such as waist circumference, body mass index, blood pressure and tobacco consumption, as well as biochemical measurements were obtained. Ultrasound imaging of carotid arteries for intima media thickness and stenosis evaluation were performed according to a standardized protocol. In comparison to the control group, the irradiated cohort members were significantly older, more frequently never smokers, hypertensive, and presented higher glycated hemoglobin and alkaline phosphatase levels. In addition, the irradiated cohort showed a higher frequency of carotid stenosis ≥30% than the nonirradiated group (13.9% vs. 10.7%), although this was not significant ( P = 0.20). Stenosis was ≥50% in 2.9% of the irradiated group and 0.4% of the nonirradiated group ( P = 0.02). Likewise, the frequency of intima media thickness ≥1 mm was significantly higher in the irradiated group (16.8% vs. 10.7%; P = 0.02). Multivariate analysis, including other cardiovascular risk factors, showed that exposure to low-dose radiation increased the risk of carotid stenosis by ≥50% [odds ratio (OR) = 8.85; P = 0.04] and intima media thickness by ≥1 mm (OR = 1.82; P = 0.02). These findings confirm that low-dose exposure is a risk factor of carotid atherosclerotic disease.
... Radiography is a vital and frequently utilized diagnostic tool in medicine, and is considered the most valuable imaging modality for examining bone fractures and other related abnormalities [1], [2]. On the other hand, medical X-ray is one of the largest artificial sources of radiation exposure to patients, workers, and the general populace, hence there exists the problem of safely delivering radiation dose when imaging biological tissues [2], [3]. This problem is caused from incorrect use of X-ray imaging equipment and from the radiation exposure to patient much more than required [4]. ...
This study aims to evaluate the effect of some exposure parameters on backscattered radiation dose to elucidate the backscattered radiation reduction capabilities of fabricated grids under different exposure sittings such as exposure intensity (mAs), exposed area (field size), dosimeter position (backscattering angle), and distance between x-ray source and imaged object surface (SSD). The results showed that, the effectiveness of fabricated anti-scatter grids in reducing backscattered radiation is dependent the radiation exposure parameters. The fabricated anti-scatter grids show the best attenuation capabilities at relatively low exposure intensity, small field size, small backscatter angle, and long SSD. Index Terms-anti-scattered X-ray grid, exposure factors, reducing backscattered radiation.
