Comparison of Biological Effects of Whole-Body Irradiation with 22.5-Mev X-Rays, 18-Mev Electrons, and 400-Kev X-Rays in the Rat

1955 ◽  
Vol 3 (4) ◽  
pp. 423 ◽  
Author(s):  
John B. Fuller ◽  
Irene Chen ◽  
John S. Laughlin ◽  
Roger A. Harvey
Keyword(s):  
Biological Effects ◽  
Whole Body ◽  
X Rays

Principles of chemotherapy

2018 ◽  
Author(s):  
Jim Cassidy ◽  
Donald Bissett ◽  
Roy A. J. Spence OBE ◽  
Miranda Payne ◽  
Gareth Morris-Stiff
Keyword(s):  
Biological Effects ◽  
Intraoperative Radiotherapy ◽  
Intensity Modulated Radiotherapy ◽  
Palliative Radiotherapy ◽  
Ionising Radiation ◽  
Whole Body ◽  
High Dose ◽  
X Rays ◽  
Image Guided Radiotherapy ◽  
Radical Treatment

Principles of radiation oncology outlines the physical and biological effects of ionising radiation, and its use in clinical oncology. Radiobiology, examining the response of tissue to ionising radiation, is described with regards to normal and malignant tissues. The effect of fractionation, the delivery of radiotherapy in a series of repeated exposures, is examined. The damaging effects on normal tissues are considered, particularly nonreversible late effects including carcinogenesis. Therapeutic exposure to ionising radiation is contrasted between radical and palliative radiotherapy. The physical properties of ionising radiation beams are described for superficial x-rays, megavoltage x-rays, and electrons. The process of treatment planning is summarised through beam dosimetry, target and critical organ outlining, dose planning, treatment verification, prescription and delivery. Computerised tomography is used for outlining and for verification, using cone beam CT. 0ther methods for image guided radiotherapy include fiducial markers. Increasingly intensity modulated radiotherapy is proving beneficial in reducing normal tissue damage during radical treatment. Stereotactic radiotherapy is used in the radical treatment of small unresectable malignancies. The clinical use of electron therapy, brachytherapy and intraoperative radiotherapy is described. Nuclear medicine uses unsealed radionuclides in imaging primary malignancies and their metastases, and in targeted radiotherapy. Examples include PET scanning, bone scanning, and radio iodine therapy. Whole body irradiation is used to improve outcomes after high-dose chemotherapy with stem cell or bone marrow transplantation.

scholarly journals Crocetin Mitigates Irradiation Injury in an In Vitro Model of the Pubertal Testis: Focus on Biological Effects and Molecular Mechanisms

Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1676
Author(s):  
Giulia Rossi ◽  
Martina Placidi ◽  
Chiara Castellini ◽  
Francesco Rea ◽  
Settimio D'Andrea ◽  
...  
Keyword(s):  
In Vitro Model ◽  
Molecular Mechanisms ◽  
Biological Effects ◽  
Cellular Damage ◽  
X Rays ◽  
Adolescent Cancer ◽  
Radiation Induced ◽  
Vitro Model ◽  
Underlying Mechanisms

Infertility is a potential side effect of radiotherapy and significantly affects the quality of life for adolescent cancer survivors. Very few studies have addressed in pubertal models the mechanistic events that could be targeted to provide protection from gonadotoxicity and data on potential radioprotective treatments in this peculiar period of life are elusive. In this study, we utilized an in vitro model of the mouse pubertal testis to investigate the efficacy of crocetin to counteract ionizing radiation (IR)-induced injury and potential underlying mechanisms. Present experiments provide evidence that exposure of testis fragments from pubertal mice to 2 Gy X-rays induced extensive structural and cellular damage associated with overexpression of PARP1, PCNA, SOD2 and HuR and decreased levels of SIRT1 and catalase. A twenty-four hr exposure to 50 μM crocetin pre- and post-IR significantly reduced testis injury and modulated the response to DNA damage and oxidative stress. Nevertheless, crocetin treatment did not counteract the radiation-induced changes in the expression of SIRT1, p62 and LC3II. These results increase the knowledge of mechanisms underlying radiation damage in pubertal testis and establish the use of crocetin as a fertoprotective agent against IR deleterious effects in pubertal period.

scholarly journals Hepatic Gene Expression Changes in Rats Internally Exposed to Radioactive 56MnO2 Particles at Low Doses

2021 ◽  
Vol 43 (2) ◽  
pp. 758-766
Author(s):  
Bakhyt Ruslanova ◽  
Zhaslan Abishev ◽  
Nailya Chaizhunussova ◽  
Dariya Shabdarbayeva ◽  
Sholpan Tokesheva ◽  
...  
Keyword(s):  
Atomic Bomb ◽  
Kinase Inhibitor ◽  
Biological Effects ◽  
Nuclear Factor Κb ◽  
Internal Exposure ◽  
Whole Body ◽  
Control Group ◽  
Gene Expressions ◽  
Γ Irradiation ◽  
Γ Rays

We have studied the biological effects of the internal exposure to radioactive manganese-56 dioxide (56MnO2), the major radioisotope dust found in soil after atomic bomb explosions. Our previous study of blood chemistry indicated a possible adverse effect of 56MnO2 on the liver. In the present study, we further examined the effects on the liver by determining changes in hepatic gene expressions. Male Wistar rats were exposed to 56MnO2 particles (three groups with the whole-body doses of 41, 90, and 100 mGy), stable MnO2 particles, or external 60Co γ-rays (2 Gy), and were examined together with the non-treated control group on postexposure day 3 and day 61. No histopathological changes were observed in the liver. The mRNA expression of a p53-related gene, the cyclin-dependent kinase inhibitor 1A, increased in 56MnO2 as well as in γ-ray irradiated groups on postexposure day 3 and day 61. The expression of a stress-responsive gene, nuclear factor κB, was also increased by 56MnO2 and γ-rays on postexposure day 3. However, the expression of cytokine genes (interleukin-6 or chemokine ligand 2) or fibrosis-related TGF-β/Smad genes (Tgfb1, Smad3, or Smad4) was not altered by the exposure. Our data demonstrated that the internal exposure to 56MnO2 particles at less than 0.1 Gy significantly affected the short-term gene expressions in the liver in a similar manner with 2 Gy of external γ-irradiation. These changes may be adaptive responses because no changes occurred in cytokine or TGF-β/Smad gene expressions.

scholarly journals Optimal LDR to Protect the Kidney From Diabetes: Whole-Body Exposure to 25 mGy X-rays Weekly for 8 Weeks Efficiently Attenuates Renal Damage in Diabetic Mice

Dose-Response ◽  
2018 ◽  
Vol 16 (3) ◽  
pp. 155932581878984 ◽  
Author(s):  
Jie Cheng ◽  
Fengsheng Li ◽  
Guanjun Wang ◽  
Weiying Guo ◽  
Shan Huang ◽  
...  
Keyword(s):  
Low Dose ◽  
Collagen Iv ◽  
Whole Body ◽  
Detectable Effect ◽  
X Rays ◽  
Diabetic Mice ◽  
Low Dose Radiation ◽  
Functional Changes ◽  
Renal Expression

To explore an optimal frequency of whole-body low-dose radiation (LDR) to protect the kidney from diabetes, type 1 diabetic mice were induced with multiple injections of low-dose streptozotocin in male C57BL/6J mice. Diabetic or age-matched normal mice received whole-body exposure to 12.5 or 25 mGy either every other day or weekly for 4 or 8 weeks. Diabetes decreased the urinary creatinine and increased the microalbumin in urine, renal accumulation of 3-nitrotyrosine and 4-hydroxynonenal, and renal expression of collagen IV and fibronectin. All these renal pathological and functional changes in diabetic mice were significantly attenuated by exposure to LDR at all regimens. However, whole-body exposure of diabetic mice to 25 mGy weekly and to 12.5 mGy every other day for 8 weeks provided a better prevention of diabetic nephropathy than other LDR regimens. Furthermore, whole-body exposure to 25 mGy weekly for 8 weeks showed no detectable effect on the kidney of normal mice, but whole-body exposure to normal mice at 12.5 mGy every other day for 8 weeks increased urinary microalbumin and renal expression of collagen IV and fibronectin. These results suggest that whole-body exposure to LDR at 25 mGy weekly is the optimal condition of LDR to protect the kidney from diabetes.

scholarly journals Plain Radiography May Be Safely Omitted for Selected Major Trauma Patients Undergoing Whole Body CT: Database Study

2012 ◽  
Vol 2012 ◽  
pp. 1-5 ◽  
Author(s):  
Sarah Hudson ◽  
Adrian Boyle ◽  
Stephanie Wiltshire ◽  
Lisa McGerty ◽  
Sara Upponi
Keyword(s):  
Major Trauma ◽  
Research Network ◽  
Whole Body ◽  
Trauma Patients ◽  
X Rays ◽  
Database Study ◽  
Primary Survey ◽  
Whole Body Ct ◽  
Plain Films ◽  
Body Ct

Introduction. Whole body CT is being used increasingly in the primary survey of major trauma patients. We evaluated whether omitting plain films of the chest and pelvis in the primary survey was safe. We compared the probability of survival of patients and time to CT who had plain X-rays to those who did not.Method. We performed a database study on major trauma patients admitted between 2008 and 2010 using data from Trauma, Audit and Research Network (TARN) and our PACS system. We included adult major trauma patients who has an ISS of greater than 15 and underwent whole body CT.Results. 245 patients were included in the study. 44 (17.9%) did not undergo plain films. The median time to whole body CT from the time of admission was longer (47 minutes) in patients having plain films, than those who did not have plain films performed (30 minutes),P<0.005. Mortality was increased in the group who received plain films, 9.5% compared to 4.5%, but this was not statistically significant (P=0.77).Conclusion. We conclude that plain films may be safely omitted during the primary survey of selected major trauma patients.

scholarly journals On the Fractional- and Whole-body Mutations Induced by Soft X-rays in Drosophila

1964 ◽  
Vol 38 (4) ◽  
pp. 288-289 ◽  
Author(s):  
Y. MATSUDAIRA ◽  
T. ITO ◽  
T. YAMASAKI ◽  
S. ISHIZAKA ◽  
M. DOMON
Keyword(s):  
Whole Body ◽  
X Rays

Labyrinthectomy decreases bone mineral density in the femoral metaphysis in rats

2004 ◽  
Vol 14 (5) ◽  
pp. 361-365
Author(s):  
Régis Levasseur ◽  
Jean Pierre Sabatier ◽  
Olivier Etard ◽  
Pierre Denise ◽  
Annie Reber
Keyword(s):  
Bone Mineral Density ◽  
Bone Mineral ◽  
Weight Bearing ◽  
Whole Body ◽  
X Rays ◽  
Mineral Density ◽  
Femoral Metaphysis ◽  
Significant Difference ◽  
Distal Femoral Metaphysis ◽  
Vestibular Influence

To determine whether the vestibular system could influence bone remodeling in rats, we measured bone mineral density with dual energy X-rays absorptiometry before and 30 days after bilateral labyrinthectomy. Comparatively to intact control rats, labyrinthectomized animals showed a reduced bone mineral density in distal femoral metaphysis (p = 0.007): the variations between D0 and D30 were +3.0% for controls and -13.9% for labyrinthectomized rats. No significant difference between the 2 groups was observed in the whole body mineral density. These results suggest that the peripheral vestibular apparatus is a modulator of bone mass and more specifically in weight bearing bone. We discuss possible mechanisms of this vestibular influence probably mediated by the sympathetic nervous system.

Radiation physics, biology, and protection

2019 ◽  
pp. 45-68
Keyword(s):  
Ionizing Radiation ◽  
Radiation Dosimetry ◽  
Biological Effects ◽  
Patient Dose ◽  
Radiation Doses ◽  
X Rays ◽  
Radiation Physics

This chapter describes the interactions of X-rays with matter, the biological effects of ionizing radiation (including estimated dose thresholds), the science behind radiation dosimetry, and principles of protection of people and the environment. It goes on to describe patient dose according to scanner design, scan parameters, and methods to manage and optimize radiation doses.

Biological Effects of Diagnostic X-rays

1958 ◽  
Vol 34 (1) ◽  
pp. 110-111 ◽  
Author(s):  
SHIELDS WARREN
Keyword(s):  
Biological Effects ◽  
X Rays
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