scholarly journals Some aspects of radiation protection in radionuclide therapy departments

2021 ◽  
Vol 14 (1) ◽  
pp. 75-85
Author(s):  
V. Yu. Golikov ◽  
L. A. Chipiga ◽  
A. V. Vodovatov ◽  
M. Ya. Smolyarchuk

The paper presents the data that allow calculate the attenuation factors in lead, tungsten and concrete of various thicknesses or the thickness of shielding made of these materials for a given attenuation factor for the spectra of gamma radiation of 131I and 177Lu radionuclides. Using these data the effectiveness of the protection of supporting equipment (portable containers, shielded syringes, etc.) and the possible doses of external radiation of medical personnel in the radionuclide therapy department were calculated. It is shown that there are short-term operations in the production process when a radiation source (container with a capsule with activity, syringe with activity), being near the body of a medical worker, creates a significant dose rate. For this reason the annual individual dose of external exposure of a medical worker can approach or exceed 1/3 of the dose limit. Calculation of the attenuation of 131I gamma radiation by stationary shield showed that the thickness of walls and floors made of concrete 200 – 400 mm will ensure that the permissible values of the dose rates of gamma radiation in the air do not exceed at annual turnover of activity in the radionuclide therapy department of ~ 3.3 · 1012 Bq.

2011 ◽  
Vol 50 (06) ◽  
pp. 240-246 ◽  
Author(s):  
R. Franssen ◽  
M. G. W. Visser ◽  
C. J. A. Urbach ◽  
S. G. E. A. Halders ◽  
M. J. Frantzen ◽  
...  

SummaryAim: The hard beta and gamma radiation of 124I can cause high doses to PET/CT workers. In this study we tried to quantify this occupational exposure and to optimize radioprotection. Methods: Thin MCP-Ns thermoluminescent dosimeters suitable for measuring beta and gamma radiation were used for extremity dosimetry, active personal dosimeters for whole-body dosimetry. Extremity doses were determined during dispensing of 124I and oral administration of the activity to the patient, the body dose during all phases of the PET/CT procedure. In addition, dose rates of vials and syringes as used in clinical practice were measured. The procedure for dispensing 124I was optimized using newly developed shielding. Results: Skin dose rates up to 100 mSv/ min were measured when in contact with the manufacturer's vial containing 370 MBq of 124I. For an unshielded 5 ml syringe the positron skin dose was about seven times the gamma dose. Before optimization of the preparation of 124I, using an already reasonably safe technique, the highest mean skin dose caused by handling 370 MBq was 1.9 mSv (max. 4.4 mSv). After optimization the skin dose was below 0.2 mSv. Conclusion: The highly energetic positrons emitted by 124I can cause high skin doses if radioprotection is poor. Under optimized conditions occupational doses are acceptable. Education of workers is of paramount importance.


Author(s):  
Dr. Rangarajan B. ◽  
Dr. Muralidhara .

Gridhrasi (Sciatica) is a disorder in which low back pain is found, that spreads through the hip, to the back of the thigh and down the inside of the leg. Mechanical low back pain (LBP) remains the second most common symptom related reason for seeing a physician. 85% of total population will experience an episode of mechanical LBP at some point during their lifetime. Fortunately, the LBP resolves for the vast majority within 2-4 weeks. There are many causes for low back pain, however true sciatica is a symptom of inflammation or compression of the sciatica nerve. The sciatica nerve carries impulses between nerve roots in the lower back and the muscles and nerve of the buttocks, thighs and lower legs. Compression of a nerve root often occurs as a result of damage to one of the discs between the vertebrae. In some cases, sciatic pain radiate from other nerves in the body. This is called referred pain. Pain associated with sciatica often is severe, sharp and shooting. It may be accompanied by other symptom, such as numbness, tingling, weakness and sensitivity to touch. There is only conservative treatment giving short term relief in pain or surgical intervention with side effect. But these are not successful and therefore those who are suffering from this are always in search of result oriented remedy. Walking distance and SLR test were taken for assessment parameter, VAS score was adopted for pain. Before treatment patient was not able to walk even 4 to 5 steps due to severe pain, was brought on stretcher and his SLR was 30° of right side. After 22 days of treatment he was able to walk up to 500 meters without any difficulty, SLR was changed to 60° and patient had got 80 % relief in pain. This case report showed that Ayurvedic protocol is potent and safe in the treatment of Gridhrasi.


2021 ◽  
pp. 152660282110074
Author(s):  
Quirina M. B. de Ruiter ◽  
Frans L. Moll ◽  
Constantijn E. V. B. Hazenberg ◽  
Joost A. van Herwaarden

Introduction: While the operator radiation dose rates are correlated to patient radiation dose rates, discrepancies may exist in the effect size of each individual radiation dose predictors. An operator dose rate prediction model was developed, compared with the patient dose rate prediction model, and converted to an instant operator risk chart. Materials and Methods: The radiation dose rates (DRoperator for the operator and DRpatient for the patient) from 12,865 abdomen X-ray acquisitions were selected from 50 unique patients undergoing standard or complex endovascular aortic repair (EVAR) in the hybrid operating room with a fixed C-arm. The radiation dose rates were analyzed using a log-linear multivariable mixed model (with the patient as the random effect) and incorporated varying (patient and C-arm) radiation dose predictors combined with the vascular access site. The operator dose rate models were used to predict the expected radiation exposure duration until an operator may be at risk to reach the 20 mSv year dose limit. The dose rate prediction models were translated into an instant operator radiation risk chart. Results: In the multivariate patient and operator fluoroscopy dose rate models, lower DRoperator than DRpatient effect size was found for radiation protocol (2.06 for patient vs 1.4 for operator changing from low to medium protocol) and C-arm angulation. Comparable effect sizes for both DRoperator and DRpatient were found for body mass index (1.25 for patient and 1.27 for the operator) and irradiated field. A higher effect size for the DRoperator than DRpatient was found for C-arm rotation (1.24 for the patient vs 1.69 for the operator) and exchanging from femoral access site to brachial access (1.05 for patient vs 2.5 for the operator). Operators may reach their yearly 20 mSv year dose limit after 941 minutes from the femoral access vs 358 minutes of digital subtraction angiography radiation from the brachial access. Conclusion: The operator dose rates were correlated to patient dose rate; however, C-arm angulation and changing from femoral to brachial vascular access site may disproportionally increase the operator radiation risk compared with the patient radiation risk. An instant risk chart may improve operator dose awareness during EVAR.


Genes ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 3
Author(s):  
Haaike Colemonts-Vroninks ◽  
Jessie Neuckermans ◽  
Lionel Marcelis ◽  
Paul Claes ◽  
Steven Branson ◽  
...  

Hereditary tyrosinemia type 1 (HT1) is an inherited condition in which the body is unable to break down the amino acid tyrosine due to mutations in the fumarylacetoacetate hydrolase (FAH) gene, coding for the final enzyme of the tyrosine degradation pathway. As a consequence, HT1 patients accumulate toxic tyrosine derivatives causing severe liver damage. Since its introduction, the drug nitisinone (NTBC) has offered a life-saving treatment that inhibits the upstream enzyme 4-hydroxyphenylpyruvate dioxygenase (HPD), thereby preventing production of downstream toxic metabolites. However, HT1 patients under NTBC therapy remain unable to degrade tyrosine. To control the disease and side-effects of the drug, HT1 patients need to take NTBC as an adjunct to a lifelong tyrosine and phenylalanine restricted diet. As a consequence of this strict therapeutic regime, drug compliance issues can arise with significant influence on patient health. In this study, we investigated the molecular impact of short-term NTBC therapy discontinuation on liver tissue of Fah-deficient mice. We found that after seven days of NTBC withdrawal, molecular pathways related to oxidative stress, glutathione metabolism, and liver regeneration were mostly affected. More specifically, NRF2-mediated oxidative stress response and several toxicological gene classes related to reactive oxygen species metabolism were significantly modulated. We observed that the expression of several key glutathione metabolism related genes including Slc7a11 and Ggt1 was highly increased after short-term NTBC therapy deprivation. This stress response was associated with the transcriptional activation of several markers of liver progenitor cells including Atf3, Cyr61, Ddr1, Epcam, Elovl7, and Glis3, indicating a concreted activation of liver regeneration early after NTBC withdrawal.


2017 ◽  
Vol 10 (4) ◽  
pp. 57
Author(s):  
Giovanni Pellegrini ◽  
Klaudia Siwowska ◽  
Stephanie Haller ◽  
Daniel Antoine ◽  
Roger Schibli ◽  
...  

2020 ◽  
Vol 11 (5) ◽  
pp. 489-509
Author(s):  
R. Cheng ◽  
H. Liang ◽  
Y. Zhang ◽  
J. Guo ◽  
Z. Miao ◽  
...  

This study aimed to determine the impact of Lactobacillus plantarum PC170 concurrent with antibiotic treatment and/or during the recovery phase after antibiotic treatment on the body weight, faecal bacterial composition, short-chain fatty acids (SCFAs) concentration, and splenic cytokine mRNA expression of mice. Orally administrated ceftriaxone quantitatively and significantly decreased body weight, faecal total bacteria, Akkermansia muciniphila, and Lactobacillus plantarum, and faecal SCFAs concentration. Ceftriaxone treatment also dramatically altered the faecal microbiota with an increased Chao1 index, decreased species diversities and Bacteroidetes, and more Firmicutes and Proteobacteria. After ceftriaxone intervention, these changes all gradually started to recover. However, faecal microbiota diversities were still totally different from control by significantly increased α- and β-diversities. Bacteroidetes all flourished and became dominant during the recovery process. However, mice treated with PC170 both in parallel with and after ceftriaxone treatment encouraged more Bacteroidetes, Verrucomicrobia, and Actinobacteria, and the diversity by which to make faecal microbiota was very much closer to control. Furthermore, the expression of splenic pro-inflammatory cytokine tumour necrosis factor-α mRNA in mice supplemented with PC170 during the recovery phase was significantly lower than natural recovery. These results indicated that antibiotics, such as ceftriaxone, even with short-term intervention, could dramatically damage the structure of gut microbiota and their abilities to produce SCFAs with loss of body weight. Although such damages could be partly recovered with the cessation of antibiotics, the implication of antibiotics to gut microbiota might remain even after antibiotic treatment. The selected strain PC170 might be a potential probiotic because of its contributions in helping the host animal to remodel or stabilise its gut microbiome and enhancing the anti-inflammatory response as protection from the side effects of antibiotic therapy when it was administered in parallel with and after antibiotic treatment.


2018 ◽  
Vol 38 (5) ◽  
Author(s):  
Lan Yi ◽  
Hongxiang Mu ◽  
Nan Hu ◽  
Jing Sun ◽  
Jie Yin ◽  
...  

Uranium tailings (UT) are formed as a byproduct of uranium mining and are of potential risk to living organisms. In the present study, we sought to identify potential biomarkers associated with chronic exposure to low dose rate γ radiation originating from UT. We exposed C57BL/6J mice to 30, 100, or 250 μGy/h of gamma radiation originating from UT samples. Nine animals were included in each treatment group. We observed that the liver central vein was significantly enlarged in mice exposed to dose rates of 100 and 250 μGy/h, when compared with nonirradiated controls. Using proteomic techniques, we identified 18 proteins that were differentially expressed (by a factor of at least 2.5-fold) in exposed animals, when compared with controls. We chose glycine N-methyltransferase (GNMT), glutathione S-transferase A3 (GSTA3), and nucleophosmin (NPM) for further investigations. Our data showed that GNMT (at 100 and 250 μGy/h) and NPM (at 250 μGy/h) were up-regulated, and GSTA3 was down-regulated in all of the irradiated groups, indicating that their expression is modulated by chronic gamma radiation exposure. GNMT, GSTA3, and NPM may therefore prove useful as biomarkers of gamma radiation exposure associated with UT. The mechanisms underlying those changes need to be further studied.


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