scholarly journals Destruction of tumor mass by gadolinium-loaded nanoparticles irradiated with monochromatic X-rays: Implications for the Auger therapy

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Kotaro Matsumoto ◽  
Hiroyuki Saitoh ◽  
Tan Le Hoang Doan ◽  
Ayumi Shiro ◽  
Keigo Nakai ◽  
...  
Keyword(s):  
Mesoporous Silica Nanoparticles ◽  
X Rays ◽  
Tumor Spheroids ◽  
Tumor Mass ◽  
X Ray ◽  
Complete Destruction ◽  
New Type ◽  
Efficient Uptake ◽  
A Site ◽  
Shell Energy

Abstract Synchrotron generated monochromatic X-rays can be precisely tuned to the K-shell energy of high Z materials resulting in the release of the Auger electrons. In this work, we have employed this mechanism to destruct tumor spheroids. We first loaded gadolinium onto the surface of mesoporous silica nanoparticles (MSNs) producing gadolinium-loaded MSN (Gd-MSN). When Gd-MSN was added to the tumor spheroids, we observed efficient uptake and uniform distribution of Gd-MSN. Gd-MSN also can be taken up into cancer cells and localize to a site just outside of the cell nucleus. Exposure of the Gd-MSN containing tumor spheroids to monochromatic X-ray beams resulted in almost complete destruction. Importantly, this effect was observed at an energy level of 50.25 keV, but not with 50.0 keV. These results suggest that it is possible to use precisely tuned monochromatic X-rays to destruct tumor mass loaded with high Z materials, while sparing other cells. Our experiments point to the importance of nanoparticles to facilitate loading of gadolinium to tumor spheroids and to localize at a site close to the nucleus. Because the nanoparticles can target to tumor, our study opens up the possibility of developing a new type of radiation therapy for cancer.

scholarly journals Iodine containing porous organosilica nanoparticles trigger tumor spheroids destruction upon monochromatic X-ray irradiation: DNA breaks and K-edge energy X-ray

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yuya Higashi ◽  
Kotaro Matsumoto ◽  
Hiroyuki Saitoh ◽  
Ayumi Shiro ◽  
Yue Ma ◽  
...  
Keyword(s):  
Mesoporous Silica Nanoparticles ◽  
Energy Levels ◽  
Tumor Spheroid ◽  
X Rays ◽  
Apoptosis Induction ◽  
Dna Breaks ◽  
Tumor Spheroids ◽  
X Ray ◽  
Double Strand Dna Breaks ◽  
Double Strand Dna

AbstractX-ray irradiation of high Z elements causes photoelectric effects that include the release of Auger electrons that can induce localized DNA breaks. We have previously established a tumor spheroid-based assay that used gadolinium containing mesoporous silica nanoparticles and synchrotron-generated monochromatic X-rays. In this work, we focused on iodine and synthesized iodine-containing porous organosilica (IPO) nanoparticles. IPO were loaded onto tumor spheroids and the spheroids were irradiated with 33.2 keV monochromatic X-ray. After incubation in CO2 incubator, destruction of tumor spheroids was observed which was accompanied by apoptosis induction, as determined by the TUNEL assay. By employing the γH2AX assay, we detected double strand DNA cleavages immediately after the irradiation. These results suggest that IPO first generate double strand DNA breaks upon X-ray irradiation followed by apoptosis induction of cancer cells. Use of three different monochromatic X-rays having energy levels of 33.0, 33.2 and 33.4 keV as well as X-rays with 0.1 keV energy intervals showed that the optimum effect of all three events (spheroid destruction, apoptosis induction and generation of double strand DNA breaks) occurred with a 33.2 keV monochromatic X-ray. These results uncover the preferential effect of K-edge energy X-ray for tumor spheroid destruction mediated by iodine containing nanoparticles.

scholarly journals Convergence of the Study on Monochromatic X-rays and the Research on Nanoparticles Opens Up a Possibility to Develop a New Type of Radiation Therapy

2020 ◽  
Author(s):  
Fuyuhiko Tamanoi ◽  
Kotaro Matsumoto ◽  
Tan Le Hoang Doan ◽  
Ayumi Shiro ◽  
Hiroyuki Saitoh
Keyword(s):  
Radiation Therapy ◽  
Cancer Cells ◽  
Mesoporous Silica Nanoparticles ◽  
Energy Levels ◽  
Cancer Therapies ◽  
X Rays ◽  
X Ray ◽  
Conventional Radiation ◽  
Combined Use ◽  
New Type

Conventional radiation therapy uses white X-rays that consist of a mixture of X-ray waves with various energy levels. In contrast, a monochromatic X-ray (monoenergetic X-ray) has a single energy level. Irradiation of high Z elements with a synchrotron generated monochromatic X-ray with the energy at or higher than the K-edge energy of the element results in the production of the Auger electrons that cause 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. Mesoporous silica nanoparticles (MSNs) have been shown to be effective in delivering high Z elements to cancer cells. A proof of principle experiment was reported that demonstrated the feasibility of this approach. This opens up a possibility to pursue the Auger cancer therapy by the combined use of MSNs loaded with high Z elements and monochromatic X-rays. Similar cancer therapies using other types of quantum beams such as neutron, proton and carbon ion beams can be envisioned.

scholarly journals Face-on SS 433 Stars as a Possible New Type of Extragalactic X-Ray Sources

2001 ◽  
Vol 205 ◽  
pp. 268-269 ◽  
Author(s):  
S. Fabrika ◽  
A. Mescheryakov
Keyword(s):  
X Rays ◽  
Relativistic Jets ◽  
Expected Frequency ◽  
X Ray ◽  
Ss 433 ◽  
Sky Survey ◽  
Supercritical Accretion ◽  
The Face ◽  
New Type ◽  
Positive Correlations

The object SS433 is a well-known source of relativistic jets, which are formed in supercritical accretion disk. It is very probable that the disk has polar channels and their radiation is collimated (the photo-cones). A face-on SS433 object can appear as ultra-bright and highly variable X-ray source, Lx ˜ 1040 − 1042 erg/s. We discuss the properties of these hypothetical objects and their frequency expected in galaxies. We describe a search for such objects using the ROSAT All Sky Survey and RC3 catalog of galaxies. Among the total 418 positive correlations we find that 142 sources in S and Irr galaxies are unknown as AGNs. Nuclear sources among them still contain many AGNs. Non-nuclear (offset) sources are rather hard, their X-ray luminosities are 1039 − 1041 erg/s. Their observed frequency is about 4–5% per galaxy, that is in agreement with expected frequency of the face-on SS 433 stars. The only way to recognize such stars is their expected violent variability in X rays.

scholarly journals IVAN PULUJ AND THE DISCOVERY OF X-RAYS

2021 ◽  
Vol 64 (1) ◽  
Author(s):  
Ulyana Pidvalna ◽  
◽  
Roman Plyatsko ◽  
Vassyl Lonchyna ◽  
◽  
...  
Keyword(s):  
International Exhibition ◽  
Bone Lesions ◽  
X Rays ◽  
High Quality ◽  
X Ray ◽  
Exact Date ◽  
Starting Point ◽  
The World ◽  
New Type ◽  
The Given

On January 5, 1896, the Austrian newspaper Die Presse published an article entitled “A Sensational Discovery”. It was dedicated to the discovery of X-rays made on November 8, 1895 by the German physicist Wilhelm Conrad Röntgen. Having taken into account the contribution of other scientists, the precondition of the given epochal, yet unexpected, discovery was, first and foremost, the work of the Ukrainian scientist Ivan Puluj. It was Puluj who laid the foundation for X-ray science. He explained the nature of X-rays, discovered that they can ionize atoms and molecules, and defined the place of X-ray emergence and their distribution in space. In 1881, Puluj constructed a cathode lamp (“Puluj’s tube”) which was fundamentally a new type of light source. In the same year, in recognition of this discovery, Puluj received an award at the International Exhibition in Paris. Investigating the processes in cathode-ray tubes, Ivan Puluj set the stage for two ground-breaking discoveries in physics, namely X-rays and electrons. Puluj used his cathode lamp in medicine as a source of intense X-rays which proved to be highly efficient. The exact date of the first X-ray images received by Puluj remains unknown. High-quality photographs of the hand of an eleven-year-old girl, taken on January 18, 1896, are preserved. Multiple X-ray images clearly visualized pathological changes in the examined structures (fractures, calluses, tuberculous bone lesions). High-quality images were obtained by means of the anticathode in the design of Puluj’s lamp, which was the first in the world. The image of the whole skeleton of a stillborn child (published on April 3, 1896 in The Photogram) is considered to be the starting point of using X-rays in anatomy.

Absorption edge imaging of bacterial endospores

1987 ◽  
Vol 45 ◽  
pp. 882-883
Author(s):  
B. J. Panessa-Warren ◽  
G. T. Tortora ◽  
J. B. Warren
Keyword(s):  
Absorption Edge ◽  
Spore Morphology ◽  
X Rays ◽  
Nitrogen Absorption ◽  
X Ray ◽  
Bacterial Endospores ◽  
Site Of Action ◽  
New Type ◽  
Chemical Sterilization ◽  
Optimal Imaging

Due to the structure and physiology of the bacterial endospore, the resist ratio for most chemical sterilants of spores to vegetative cells is 10,000:1 thereby making them uniquely resistant to chemical sterilization. Although some chemical sterilants do exist that are quite effective against most species of spores, little is known about the effect these chemicals have on spore morphology. This investigation involves the application of a relatively new vanadium-containing sporocide to viable Bacillus subtilis and B. Thuringiensis spores and subsequent microscopy and viability studies to analyze the changes produced after 30 sec, 5 min, 10 min 50 min and 80 min exposure. To try and identify the role, and site of action, of vanadium during spore destruction we attempted a new type of x-ray microscopy utilizing monochromatic x-rays above and below the absorption edge of vanadium (V LII edge). Control x-ray replicas were made at the nitrogen absorption edge (3.09nm) for orientation purposes due to the optimal imaging of protein within the spore. Scanning electron microscopy of sporocide-treated and untreated endospores were used for comparison.

Silicon Detector System for X-Ray Pulse Calorimetry of Laser-Produced Plasmas*

1974 ◽  
Vol 18 ◽  
pp. 213-221 ◽  
Author(s):  
J. H. McQuaid ◽  
C. E. Violet ◽  
J. Petruzzi
Keyword(s):  
Silicon Detector ◽  
Direct Conversion ◽  
X Rays ◽  
Electron Pairs ◽  
Analog To Digital ◽  
X Ray ◽  
New Type ◽  
A Charge ◽  
Readout Scheme ◽  
Charge Sensitive Preamplifier

AbstractThe instrumentation for measuring x-ray yields from laser produced plasma is described. This new type of calorimeter is composed of a silicon detector, a charge-sensitive preamplifier and an analog-to-digital readout scheme for multiplexing up to ten detector outputs.X-rays interacting with the detector produce hole-electron pairs in proportion to the total energy lost in the detector (∼1012 eV). In this application the detector can be characterized as a solid-state ionization chamber. The detector signal is coupled to a charge-sensitive preamplifier which generates a voltage pulse proportional to the x-ray energy absorbed. In this way the x-ray energy is measured by “direct conversion” rather than measuring the temperature rise due to an energy flux.

Heavy Ion-Induced Characteristic X-Ray Generation as an Analytical Probe

1970 ◽  
Vol 14 ◽  
pp. 173-183 ◽  
Author(s):  
J. A. Cairns ◽  
D. F. Holloway ◽  
R. S. Nelson
Keyword(s):  
Cross Sections ◽  
Heavy Ions ◽  
Proton Irradiation ◽  
Heavy Ion ◽  
X Rays ◽  
X Ray ◽  
The Past ◽  
Tracer Techniques ◽  
New Type ◽  
Gas Volume

AbstractIncreasing attention is currently focused on the generation of characteristic x-ray by proton irradiation. This has the advantage of yielding “clean” x-ray- i. e. free from background brerasstrahlung radiation, from even the lightest elements. The disadvantage is that the yields are naturally much lower than those produced by electrons of the same energy. A recent study has extended characteristic x-ray production to a variety of heavy ions and has shown that the cross- sections for the production of clean x-rays are often higher , by as much as several orders of magnitude, than those produced by protons of the same energy. In addition, there has emerged a further advantage, viz. the ability of specially chosen heavy ions to excite characteristic x-ray from a particular element in a selective manner. Since heavy ions penetrate only a few hundred Angstroms in to most solids, the phenomenon can be used as the basis of a technique for the examination of surface deposits, or to measure depth distributions of impurities. For example, Kr ions can be used t o determine the range distribution of antimony which had been implanted in to silicon at 100 keV. The antimony concentration was determined as a function of ∼ 150 Å steps, and was found to exhibit a maximum concentration of ∼ 1 part in 103 of silicon at 450 Å below the surface, falling to zero concentration at ∼2000 Å a depth. In the past, in order to obtain the required degree of sensitivity, such range determinations have relied on radio active tracer techniques.An entirely new type of proportional counter has been developed during the course of these studies. This instrument, because of its special construction, can be positioned very close to targets in non-dispersive studies, so as to collect the highest possible fraction of emitted x-ray. It incorporates a replaceable anode unit, together with a built- in miniature head amplifier, and exhibits extremely good performance, particularly for ultra-soft x-ray. In addition, rotation of a dial on the end of the counter body allows alteration of the active gas volume during operation, and so permits tuning into x-rays of a particular energy.

scholarly journals X-ray induced photodynamic therapy with copper-cysteamine nanoparticles in mice tumors

2019 ◽  
Vol 116 (34) ◽  
pp. 16823-16828 ◽  
Author(s):  
Samana Shrestha ◽  
Jing Wu ◽  
Bindeshwar Sah ◽  
Adam Vanasse ◽  
Leon N Cooper ◽  
...  
Keyword(s):  
Photodynamic Therapy ◽  
Treatment Method ◽  
The Body ◽  
Target Cells ◽  
X Rays ◽  
X Ray ◽  
Mouse Tumors ◽  
Study Results ◽  
New Type

Photodynamic therapy (PDT), a treatment that uses a photosensitizer, molecular oxygen, and light to kill target cells, is a promising cancer treatment method. However, a limitation of PDT is its dependence on light that is not highly penetrating, precluding the treatment of tumors located deep in the body. Copper-cysteamine nanoparticles are a new type of photosensitizer that can generate cytotoxic singlet oxygen molecules upon activation by X-rays. In this paper, we report on the use of copper-cysteamine nanoparticles, designed to be targeted to tumors, for X-ray–induced PDT. In an in vivo study, results show a statistically significant reduction in tumor size under X-ray activation of pH-low insertion peptide–conjugated, copper-cysteamine nanoparticles in mouse tumors. This work confirms the effectiveness of copper-cysteamine nanoparticles as a photosensitizer when activated by radiation and suggests that these Cu-Cy nanoparticles may be good candidates for PDT in deeply seated tumors when combined with X-rays and conjugated to a tumor-targeting molecule.

Development of a Gel Type Dosimeter for X-Ray Fields

2017 ◽  
Author(s):  
Yutaro Aoki ◽  
Glenn Harvel ◽  
Toshiharu Sakura ◽  
Takeyoshi Sunagawa
Keyword(s):  
Dose Distribution ◽  
Active Agent ◽  
X Rays ◽  
X Ray ◽  
Red Color ◽  
Oxygen Contamination ◽  
Applied Dose ◽  
New Type ◽  
Plastic Containers ◽  
Radiation Beams

In recent years, use of radiation beams or particle beams have been put to practical use for cancer therapy. In cancer radiation therapy, visualization of radiation patterns is absolutely necessary for precisely evaluating the dose distribution. Therefore, gel type or Fricke type dosimeters [1] are considered useful for visualization. In this study, we developed a new type of gel dosimeter using a doped polyvinyl alcohol (PVA) based solution. This gel uses a red color based chemical reaction that occurs when the active agent is separated. Irradiation of the gel with X-rays is sufficient to break the chemical bonds of the active agent. We irradiated different gel samples with X-rays from a Hitachi MBR-1520R-3 source under different configurations to test the gel performance. We used UV-VIS spectrometry to measure the absorbance of transmitted light through the gel. For the active agent, the absorbance is at a peak wavelength of 490 nm. The amount of absorbance is proportional to the number of interactions with X-rays. We irradiated the gel between 0.5Gy-10Gy with visualization of the gel by photography and spectrometry between each irradiation. The spectrometry was performed using a StellarNet Black Comet system observing the absorbance between 300nm and 600nm. The results show that as the X-ray dose increases, the gel transitions from a clear gel to a light pink gel and then to a red gel. All colors are translucent and allow for the passage of light. The first samples were done in clear plastic containers of 250 ml size. The containers were filled with gel to eliminate air and possible oxygen contamination. The second set of experiments repeated the first study but used metallic coins as X-ray shields. The regions covered by the coins were protected from the dose and remained clear. A sharp edge was observed at the edge of the coin. This implies that the gel does not diffuse and hence can represent a dose distribution as long as it is not mixed. The third samples were placed in disposable cells for measurement of absorbance. The absorbance had a peak in the vicinity wavelength of 490nm. The results confirmed the absorbance to be proportional for increasing applied dose. In summary, a color transition gel was developed for use in detecting irradiation dose from X-rays. This technique has potential application for visualization of dose during medical procedures.

Characterization and interpretation of the quantum efficiencies of multilayer semiconductor detectors using a new theory

1998 ◽  
Vol 5 (3) ◽  
pp. 877-879
Author(s):  
T. Cho ◽  
M. Hirata ◽  
J. Kohagura ◽  
Y. Sakamoto ◽  
T. Okamura ◽  
...  
Keyword(s):  
Heavy Particle ◽  
Current Mode ◽  
High Energy ◽  
Detector Response ◽  
Semiconductor Detectors ◽  
X Rays ◽  
Fusion Plasma ◽  
X Ray ◽  
New Type ◽  
High Bias

On the basis of a new theory of semiconductor X-ray detector response, a new type of multilayer semiconductor detector was designed and developed for convenient energy analyses of intense incident X-ray flux in a cumulative-current mode. Another anticipated useful property of the developed detector is a drastic improvement in high-energy X-ray response ranging over several hundred eV. The formula for the quantum efficiency of multilayer semiconductor detectors and its physical interpretations are proposed and have been successfully verified by synchrotron radiation experiments at the Photon Factory. These detectors are useful for data analyses under strong radiation-field conditions, including fusion-plasma-emitting X-rays and energetic heavy-particle beams, without the use of high-bias applications.

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