scholarly journals The frequency of lymphocytes containing dumbbell-shaped nuclei depends on ionizing radiation dose and correlates with appearance of chromosomal aberrations

2018 ◽  
Vol 9 (1) ◽  
pp. 1
Author(s):  
ViacheslavYu Kravtsov ◽  
AlexandraA Livanova ◽  
OlegV Belyakov ◽  
ReginaF Fedortseva
2021 ◽  
Vol 65 (5) ◽  
pp. 29-34
Author(s):  
O. Tsymbal ◽  
D. Isubakova ◽  
E. Bronikovskaya ◽  
I. Milto ◽  
M. Khalyuzova ◽  
...  

Purpose: To study the relationship between the methylation status of the Bаk1 promoter and the frequency of chromosomal aberrations in human blood lymphocytes under chronic low-intensity external ionizing radiation. Material and methods: The study was performed on 41 people (31 men and 10 women, aged from 36 to 83 years) who are former or current employees of the Siberian Group of Chemical Enterprises, who have been exposed or haven't been exposed to chronic low-intensity external radiation in the course of their professional activities. The workers included in the study were divided into two groups: the first – 15 people who did not have exposure, the second – 26 people who had external exposure (gamma radiation, total dose 89–716 mSv). Whole blood was used to isolate DNA and evaluate chromosomal aberrations in lymphocytes. The methylation status of the Bаk1 promoter was determined using methylsensitive PCR, which was performed after pretreatment of the isolated DNA with methylsensitive AoxI restrictase. The obtained quantitative data were analyzed using the Statistica 10. The differences were considered statistically significant at p ≤ 0.05. Results: The methylation status of the Bаk1 promoter in the study groups does not differ (p = 0.18). The study of the effect of external radiation dose on the methylation status of the Bak1 promoter showed that the unmethylated promoter prevails in workers with an average radiation dose of 273.37 ± 43.82 mSv, while the methylated promoter – in workers with an average radiation dose of 183.63 ± 20.58 mSv (p = 0.03). The unmethylated promoter Bаk1 is associated with an increased frequency of chromatid fragments in the blood lymphocytes of group 2 workers (p = 0.03). Conclusion: The status of methylation of the Bаk1 promoter in human blood lymphocytes under chronic low-intensity ionizing radiation does not change, but it is observed to depend on the radiation dose and is associated with an increased frequency of chromosomal aberrations (chromatid fragments). Thus, the unmethylated Bаk1 promoter prevails when the external radiation dose is increased. An increase in the frequency of chromatid fragments is associated with an unmethylated Bаk1 promoter. In addition, exposure to chronic low-intensity external radiation is accompanied by a decrease in the frequency of chromosomal fragments in the blood lymphocytes of workers of the Siberian Group of Chemical Enterprises.


2009 ◽  
Vol 62 (7-8) ◽  
pp. 314-319
Author(s):  
Svetlana Stosic-Divjak ◽  
Ivana Novakovic ◽  
Dragana Kastratovic ◽  
Milan Pavlovic ◽  
Isidora Divjak ◽  
...  

Introduction. The authors present the results of cytogenetic analysis of 21 patients with laryngeal carcinomas diagnosed and treated in the period 1995-2000 at the Institute of Otorhinolaryngology and Maxillofacial Surgery, Clinical Center of Serbia and Clinical Center of Novi Sad. Material and methods. The patients were specially monitored and the material was analyzed at the Institute of Human Genetics of the School of Medicine in Belgrade as well as in the Laboratory for Radiological Protection of the Institute of Occupational and Radiological Health 'Dr Dragomir Karajovic' in Belgrade. Results. The incidence of chromosomal aberrations and incidence of exchange of material between sister chromatids were observed in the preparation of the metaphasic lymphocyte chromosomes of the peripheral blood obtained in the culture. Structural aberrations were found on the chromosomes in the form of breakups, rings, translocations and dicentrics as early as after a single exposure of patients to tumor radiation dose of 2 Gy in the field sized 5x7. Out of the total number of 35 cultivated blood samples obtained from 13 patients, 21 were successfully cultivated and they were proved to contain chromosomal aberrations. Some of the peripheral blood samples failed to show cell growth in vitro due to the lethal cell damages in vivo. Discussion.. We have consluded that the number of structural aberrations cannot be used as a biological measure of the absorbed ionizing radiation dose. The presence of aberrations per se is indicative of the mutagenic effect of the ionizing radiation, which was also confirmed in our series on the original model by cultivation of the peripheral blood lymphocytes in the culture of the cells of the volunteer donors upon in vitro radiation. Using the method of bromdeoxyuridylreductase, the increased incidence of SCE as a mutagenic effect was registered. Conclusion. It has been concluded that the increase of absorbed radiation dose in vitro leads to prolonged duration of cell cycle in the same conditions, which proves cytostatic effect of radiation. Further fundamental studies are required for clinical implementation of the findings.


2021 ◽  
Vol 26 (1) ◽  
Author(s):  
Ning Liu ◽  
Yang Peng ◽  
Xinguang Zhong ◽  
Zheng Ma ◽  
Suiping He ◽  
...  

Abstract Background Numerous studies have concentrated on high-dose radiation exposed accidentally or through therapy, and few involve low-dose occupational exposure, to investigate the correlation between low-dose ionizing radiation and changing hematological parameters among medical workers. Methods Using a prospective cohort study design, we collected health examination reports and personal dose monitoring data from medical workers and used Poisson regression and restricted cubic spline models to assess the correlation between changing hematological parameters and cumulative radiation dose and determine the dose-response relationship. Results We observed that changing platelet of 1265 medical workers followed up was statistically different among the cumulative dose groups (P = 0.010). Although the linear trend tested was not statistically significant (Ptrend = 0.258), the non-linear trend tested was statistically significant (Pnon-linear = 0.007). Overall, there was a correlation between changing platelets and cumulative radiation dose (a change of βa 0.008 × 109/L during biennially after adjusting for gender, age at baseline, service at baseline, occupation, medical level, and smoking habits; 95% confidence interval [CI] = 0.003,0.014 × 109/L). Moreover, we also found positive first and then negative dose-response relationships between cumulative radiation dose and changing platelets by restricted cubic spline models, while there were negative patterns of the baseline service not less than 10 years (− 0.015 × 109/L, 95% CI = − 0.024, − 0.007 × 109/L) and radiation nurses(− 0.033 × 109/L, 95% CI = − 0.049, − 0.016 × 109/L). Conclusion We concluded that although the exposure dose was below the limit, medical workers exposed to low-dose ionizing radiation for a short period of time might have increased first and then decreased platelets, and there was a dose-response relationship between the cumulative radiation dose and platelets changing.


Author(s):  
Jwalant S. Mehta ◽  
Kirsten Hodgson ◽  
Lu Yiping ◽  
James Swee Beng Kho ◽  
Ravindra Thimmaiah ◽  
...  

Aims To benchmark the radiation dose to patients during the course of treatment for a spinal deformity. Methods Our radiation dose database identified 25,745 exposures of 6,017 children (under 18 years of age) and adults treated for a spinal deformity between 1 January 2008 and 31 December 2016. Patients were divided into surgical (974 patients) and non-surgical (5,043 patients) cohorts. We documented the number and doses of ionizing radiation imaging events (radiographs, CT scans, or intraoperative fluoroscopy) for each patient. All the doses for plain radiographs, CT scans, and intraoperative fluoroscopy were combined into a single effective dose by a medical physicist (milliSivert (mSv)). Results There were more ionizing radiation-based imaging events and higher radiation dose exposures in the surgical group than in the non-surgical group (p < 0.001). The difference in effective dose for children between the surgical and non-surgical groups was statistically significant, the surgical group being significantly higher (p < 0.001). This led to a higher estimated risk of cancer induction for the surgical group (1:222 surgical vs 1:1,418 non-surgical). However, the dose difference for adults was not statistically different between the surgical and non-surgical groups. In all cases the effective dose received by all cohorts was significantly higher than that from exposure to natural background radiation. Conclusion The treatment of spinal deformity is radiation-heavy. The dose exposure is several times higher when surgical treatment is undertaken. Clinicians should be aware of this and review their practices in order to reduce the radiation dose where possible.


2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Richard G. Kavanagh ◽  
John O’Grady ◽  
Brian W. Carey ◽  
Patrick D. McLaughlin ◽  
Siobhan B. O’Neill ◽  
...  

Magnetic resonance imaging (MRI) is the mainstay method for the radiological imaging of the small bowel in patients with inflammatory bowel disease without the use of ionizing radiation. There are circumstances where imaging using ionizing radiation is required, particularly in the acute setting. This usually takes the form of computed tomography (CT). There has been a significant increase in the utilization of computed tomography (CT) for patients with Crohn’s disease as patients are frequently diagnosed at a relatively young age and require repeated imaging. Between seven and eleven percent of patients with IBD are exposed to high cumulative effective radiation doses (CEDs) (>35–75 mSv), mostly patients with Crohn’s disease (Newnham E 2007, Levi Z 2009, Hou JK 2014, Estay C 2015). This is primarily due to the more widespread and repeated use of CT, which accounts for 77% of radiation dose exposure amongst patients with Crohn’s disease (Desmond et al., 2008). Reports of the projected cancer risks from the increasing CT use (Berrington et al., 2007) have led to increased patient awareness regarding the potential health risks from ionizing radiation (Coakley et al., 2011). Our responsibilities as physicians caring for these patients include education regarding radiation risk and, when an investigation that utilizes ionizing radiation is required, to keep radiation doses as low as reasonably achievable: the “ALARA” principle. Recent advances in CT technology have facilitated substantial radiation dose reductions in many clinical settings, and several studies have demonstrated significantly decreased radiation doses in Crohn’s disease patients while maintaining diagnostic image quality. However, there is a balance to be struck between reducing radiation exposure and maintaining satisfactory image quality; if radiation dose is reduced excessively, the resulting CT images can be of poor quality and may be nondiagnostic. In this paper, we summarize the available evidence related to imaging of Crohn’s disease, radiation exposure, and risk, and we report recent advances in low-dose CT technology that have particular relevance.


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