Study on the Size Dependence of AuNPs in Enhancement Radiation Effect for Superficial Kilovoltage X-Rays

2019 ◽  
Vol 290 ◽  
pp. 81-86
Author(s):  
Nur Shafawati binti Rosli ◽  
Azhar Abdul Rahman ◽  
Azlan Abdul Aziz ◽  
Shaharum Shamsuddin ◽  
Suhana Arshad
Keyword(s):  
Radiation Therapy ◽  
Free Radicals ◽  
Radiation Effects ◽  
Radiation Effect ◽  
Photoelectric Effect ◽  
Enhancement Effect ◽  
X Rays ◽  
Dose Enhancement ◽  
X Ray ◽  
Mcf 7

Radiation therapy and chemotherapy remain the most widely used treatment options in treating cancer. Recent developments in cancer research show that therapy combined with high-atomic number materials such as gold nanoparticles (AuNPs) is a new way to treat cancer, in which AuNPs are injected through intravenous administration and bound to tumor sites has enhanced tumor cell killing. Radiation therapy aims to deliver a high therapeutic dose of ionizing radiation to the tumor without exceeding normal tissue tolerance. In this work AuNPs have been used for the enhancement of radiation effects on breast cancer cells (MCF-7) for superficial kilovoltage X-ray radiation therapy. The use of AuNPs in superficial kilovoltage X-ray beams radiation therapy will provide a high probability for photon interaction by photoelectric effect. These provide advantages in terms of radiation dose enhancement. In this work, MCF-7 cells were seeded in the 96-well plate and treated with 13 nm, 50 nm and 70 nm AuNPs before they were irradiated with 80 kVp X-rays beam at various radiation doses. Photoelectric effect is the dominant process of interaction of 80 kVp X-rays with AuNPs. When the AuNPs are internalized into the MCF-7 cells, the dose enhancement effect is observed. The presence of AuNPs in the MCF-7 cells will produce a higher number of photoelectrons, and resulting more “free radicals” that will lead to increase in cell death. Then, these free radicals will lead to DNA damage to the MCF-7 cells. To validate the enhanced killing effect, both with and without AuNPs MCF-7 cells is irradiated simultaneously. By comparison, the results show that AuNPs significantly enhance cancer killing and the enhancement radiation effect was dependent on the size of AuNPs.

scholarly journals A rebirth of radiation therapy with kV X-rays?

2019 ◽  
Vol 23 ◽  
pp. 85
Author(s):  
J. Kalef-Ezra
Keyword(s):  
Radiation Therapy ◽  
Experimental Models ◽  
X Rays ◽  
Dose Enhancement ◽  
X Ray ◽  
Normal Tissues ◽  
And Migration ◽  
Tissue Sparing ◽  
Dose Measurements ◽  
Therapy Studies

Novel clinical approaches using kV X-ray beams are currently under study, such as selective dose enhancement in malignant tissues due to the enhanced presence of atoms with high atomic number, Z, in tumors relative to normal tissues or the use of heavily spatially fractionated kV X-ray irradiation.Local dose enhancement by high Z atoms: A substantial dose gradient between normal and malignant tissues can be achieved by biologic targeting the cells to be “destroyed” with high Z atoms and its irradiation with photons in the energy region of tens of keV, such as synchrotron produced X-rays of energy above the K-edge. The selective accumulation of high Z atoms can be achieved by various techniques, such as by intravenous administration of a) contrast enhancement agents, b) some chemotherapeutic drugs c) nanoparticles and d) DNA precursors loaded with Z-atoms. Taking into account the limited availability and the high cost of GeV synchrotrons, brachytherapy sources could be used.Microbeam radiation therapy: Studies carried out in experimental models using spatially micro- fractionated beams have shown drastically elevated tissue radiation tolerance, with higher tissue sparing in healthy tissues than in malignant ones. This phenomenon is attributed by some investigators to the proliferation and migration of cells from the “low” dosed regions (~10 Gy) to the adjacent “heavily” dosed regions (many hundreds of grays). Multi-slit collimators allow for the production of X-ray microbeam arrays at 3rd generation synchrotron units. Monte Carlo simulations were tested versus direct dose measurements. Promising preclinical studies carried out so far, trigger studies on the development of alternative less expensive technologies.

scholarly journals Studies on the Exposure of Gadolinium Containing Nanoparticles with Monochromatic X-rays Drive Advances in Radiation Therapy

Nanomaterials ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 1341 ◽  
Author(s):  
Fuyuhiko Tamanoi ◽  
Kotaro Matsumoto ◽  
Tan Le Hoang Doan ◽  
Ayumi Shiro ◽  
Hiroyuki Saitoh
Keyword(s):  
Radiation Therapy ◽  
Energy Levels ◽  
Photoelectric Effect ◽  
X Rays ◽  
Inhibit Tumor Growth ◽  
Auger Electrons ◽  
X Ray ◽  
Conventional Radiation ◽  
Gold Silver ◽  
Recent Addition

While conventional radiation therapy uses white X-rays that consist of a mixture of X-ray waves with various energy levels, a monochromatic X-ray (monoenergetic X-ray) has a single energy level. Irradiation of high-Z elements such as gold, silver or gadolinium with a synchrotron-generated monochromatic X-rays with the energy at or higher than their K-edge energy causes a photoelectric effect that includes release of the Auger electrons that induce DNA damage—leading to cell killing. Delivery of high-Z elements into cancer cells and tumor mass can be facilitated by the use of nanoparticles. Various types of nanoparticles containing high-Z elements have been developed. A recent addition to this growing list of nanoparticles is mesoporous silica-based nanoparticles (MSNs) containing gadolinium (Gd–MSN). The ability of Gd–MSN to inhibit tumor growth was demonstrated by evaluating effects of irradiating tumor spheroids with a precisely tuned monochromatic X-ray.

scholarly journals Radiation effects of nuclear physics rays on hepatoma cells

Open Physics ◽  
2019 ◽  
Vol 17 (1) ◽  
pp. 167-176
Author(s):  
Wenhui Zhao ◽  
Lu Cong ◽  
Yolanda Guerrero-Sánchez
Keyword(s):  
Nuclear Physics ◽  
Traditional Method ◽  
Irradiation Dose ◽  
Radiation Effects ◽  
Radiation Effect ◽  
Hepatoma Cells ◽  
X Rays ◽  
X Ray ◽  
Positive Rate ◽  
Γ Rays

Abstract The traditional method of cloning formation is used to study the radiation effect of nuclear physics rays on hepatoma cells, and the results obtained are not reliable. Therefore, a new method of studying the radiation effect of nuclear physics rays on hepatoma cells is proposed. PCC method is used to study the radiation effect of γ-rays on hepatoma cells. Radiation effects of X-rays on hepatoma cells were studied by radionuclide formation assay, neutral comet electrophoresis and γH2AX focal detection. The results showed that the survival curves of HepG2 hepatoma cells irradiated by γ-rays were well fitted by linear squares. There was a linear relationship between the survival rate and irradiation dose of HepG2 hepatoma cells irradiated by γ-rays. HepG2 hepatoma cells showed strong tolerance to X-ray irradiation, and the positive rate of γH2AX cells reached 100% in each dose group only 0.5 h after X-ray irradiation.

In Situ Testing and X Rays Radiation Effects of Pt/Bi3.15Nd0.85Ti3O12/Pt Ferroelectric Capacitors

2013 ◽  
Vol 712-715 ◽  
pp. 293-297
Author(s):  
Li Li
Keyword(s):  
Radiation Effects ◽  
Hysteresis Loops ◽  
Electrical Performance ◽  
Hysteresis Curve ◽  
X Rays ◽  
Shanghai Synchrotron Radiation Facility ◽  
X Ray ◽  
In The Beginning ◽  
Ferroelectric Capacitors

Pt/Bi3.15Nd0.85Ti3O12(BNT)/Pt ferroelectric capacitors were monitored using in situ X-ray irradiation with 10 keV at BL14B1 beamline (Shanghai Synchrotron Radiation Facility). BL14B1 combined with a ferroelectric analyzer enabled measurements in situ of electrical performance. The hysteresis curve (PE) of distortion depended on the polarization during irradiation, but the diffracted intensities of the (117) peak did not change in the beginning. ThePEcurve had a negligible change from 2.09×109Gy to 4.45×109Gy. Finally, bothPrandPr+very rapidly increased, but the intensities of (117) decreased. The hysteresis loops were remarkably deformed at the maximum total dose of 4.87×109Gy.

Preliminary Study on the Anti-radiation Effect of Jen-Sheng-Yang-Yung-Tang

1993 ◽  
Vol 21 (02) ◽  
pp. 187-195 ◽  
Author(s):  
Hsue-yin Hsu ◽  
Yau-hui Ho ◽  
Shi-Iong Lian ◽  
Chun-ching Lin
Keyword(s):  
Bone Marrow ◽  
Radiation Effect ◽  
Bone Marrow Cells ◽  
X Rays ◽  
Male Mice ◽  
X Ray ◽  
Colony Forming Units ◽  
Before And After ◽  
Preliminary Study ◽  
Different Doses

Six to seven week old male mice of ICR strain were exposed to different doses of x-rays to determine if Jen-Sheng-Yang-Yung-Tang could be a modifier in the elimination of radiation damage. Colony forming units of bone marrow cells in the spleen (CFUs) were measured before and after x-ray irradiation with intraperitoneal injection of 10 mg/20 g or 20 mg/20 g body weight of Jen-Sheng-Yang-Yung-Tang, once a day for seven consecutive days. The recovery of CFUs and hemocytes counts by 4 Gy irradiation with Jen-Sheng-Yang-Yung-Tang administration was faster for a concentration of 20 mg/20 g than 10 mg/20 g. The measurement of 10-day CFUs showed an increase of radiotolerance in the treatment of 20 mg/20 g administration before x-ray irradiation. The injection of Jen-Sheng-Yang-Yung-Tang accelerated the recovery of hemocyte counts in mice irradiated with 4 Gy x-ray; the effect was especially profound for leukocytes with 20 mg/20 g Jen-Sheng-Yang-Yung-Tang administration after irradiation.

scholarly journals Effects of Nanoparticle Size and Radiation Energy on Copper-Cysteamine Nanoparticles for X-ray Induced Photodynamic Therapy

Nanomaterials ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 1087
Author(s):  
Bindeshwar Sah ◽  
Jing Wu ◽  
Adam Vanasse ◽  
Nil Kanatha Pandey ◽  
Lalit Chudal ◽  
...  
Keyword(s):  
Radiation Therapy ◽  
Reactive Oxygen Species Production ◽  
Radiation Energy ◽  
Nanoparticle Size ◽  
Oxygen Species ◽  
X Rays ◽  
Therapy Outcomes ◽  
X Ray ◽  
Average Size ◽  
Species Production

The Copper-cysteamine (Cu-Cy) nanoparticle is a novel sensitizer with a potential to increase the effectiveness of radiation therapy for cancer treatment. In this work, the effect of nanoparticle size and the energy of X-rays on the effectiveness of radiation therapy are investigated. The effect of the particle size on their performance is very complicated. The nanoparticles with an average size of 300 nm have the most intense photoluminescence, the nanoparticles with the average size of 100 nm have the most reactive oxygen species production upon X-ray irradiation, while the nanoparticles with the average size of 40 nm have the best outcome in the tumor suppression in mice upon X-ray irradiation. For energy, 90 kVp radiation resulted in smaller tumor sizes than 250 kVp or 350 kVp radiation energies. Overall, knowledge of the effect of nanoparticle size and radiation energy on radiation therapy outcomes could be useful for future applications of Cu-Cy nanoparticles.

scholarly journals Calculation of radiation dose enhancement by gadolinium compounds for radiation therapy

2022 ◽  
Vol 2155 (1) ◽  
pp. 012030
Author(s):  
G.A. Abdullaeva ◽  
G.A. Kulabdullaev ◽  
A.A. Kim ◽  
A.F. Nebesny ◽  
D.O. Yuldashev
Keyword(s):  
Radiation Therapy ◽  
Contrast Agent ◽  
Biological Tissue ◽  
Radiation Energy ◽  
Dose Enhancement ◽  
X Ray ◽  
Photon Irradiation ◽  
Irradiation Energy ◽  
Gd Contrast Agent ◽  
Shell Ionization

Abstract In this study, we evaluate the features of dose enhancement with Gd contrast agent (Magnevist). Due to the increased relaxation time and high atomic number (z=64) Gd can be used in radiation therapy as a radiosensitizer. To perform a quantitative evaluation of the radiosensitization effect is determined a parameter called the dose enhancement factor - DEF. The DEF values were calculated based on the analysis of the mass absorption coefficients for gadolinium and biological tissue. An increase in DEF is observed when the radiation energy is higher than the K-shell ionization energy of Gd atoms. For the presence of 20315 ppm Gd contrast agent in biological tissue the dose enrichment factor is maximum DEF = 4.12 at photon irradiation energy 60 keV. Also, based on calculations for photon irradiation sources considered high degrees of dose enhancement occur for Am-241, Yb-196, and 100 kVp X-ray tube.

Interaction of ionizing radiations with matter

2015 ◽  
Author(s):  
Colin J Martin
Keyword(s):  
Radiation Dose ◽  
Scattered Radiation ◽  
Final Section ◽  
Radioactive Decay ◽  
Photoelectric Effect ◽  
X Rays ◽  
X Ray ◽  
Radiation Fields ◽  
Ionizing Radiations ◽  
Radiology Image

Interactions of ionizing radiations with matter are fundamental to the practice of radiation protection. They determine the magnitude and distribution of doses in tissues, the performance of detectors and imaging devices, and the attenuating properties of shielding materials. This chapter describes briefly the processes of radioactive decay and the properties of the various particles emitted, and then goes on to consider the interactions of radiation with matter. Electron interactions with metals result in bremsstrahlung and characteristic X-rays that form the basis of X-ray production. The interaction mechanisms of X-rays with tissue, particularly the photoelectric effect and Compton scattering, are inherent in the process of radiology image formation. Understanding the physics behind X-ray interactions so that scattered radiation can be taken into account is crucial in designing methods for accurately measuring radiation dose parameters. The final section deals with the dose related variables involved in measurement of radiation fields.

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