X Ray Irradiation

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Weiqiang Chen - One of the best experts on this subject based on the ideXlab platform.

  • ultra small gadolinium oXide nanocrystal sensitization of non small cell lung cancer cells toward X Ray Irradiation by promoting cytostatic autophagy
    International Journal of Nanomedicine, 2019
    Co-Authors: Xiaodong Jin, Yan Liu, Pengcheng Zhang, Zheyu Shen, Weiqiang Chen
    Abstract:

    Background Gadolinium-based nanoparticles (GdNPs) have been used as theranostic sensitizers in clinical radiotherapy studies; however, the biomechanisms underlying the radio-sensitizing effects of GdNPs have yet to be determined. In this study, ultra-small gadolinium oXide nanocrystals (GONs) were employed to investigate their radiosensitizing effects and biological mechanisms in non-small-cell lung cancer (NSCLC) cells under X-Ray Irradiation. Method and materials GONs were synthesized using polyol method. HydroXyl radical production, oXidative stress, and clonogenic survival after X-Ray Irradiation were used to evaluate the radiosensitizing effects of GONs. DNA double-strand breakage, cell cycle phase, and apoptosis and autophagy incidences were investigated in vitro to determine the radiosensitizing biomechanism of GONs under X-Ray Irradiation. Results GONs induced hydroXyl radical production and oXidative stress in a dose- and concentration-dependent manner in NSCLC cells after X-Ray Irradiation. The sensitizer enhancement ratios of GONs ranged between 19.3% and 26.3% for the NSCLC cells under investigation with a 10% survival rate compared with that of the cells treated with Irradiation alone. Addition of 3-methyladenine to the cell medium decreased the incidence rate of autophagy and increased cell survival, supporting the idea that the GONs promoted cytostatic autophagy in NSCLC cells under X-Ray Irradiation. Conclusion This study eXamined the biological mechanisms underlying the radiosensitizing effects of GONs on NSCLC cells and presented the first evidence for the radiosensitizing effects of GONs via activation of cytostatic autophagy pathway following X-Ray Irradiation.

  • the synergistic radiosensitizing effect of tirapazamine conjugated gold nanoparticles on human hepatoma hepg2 cells under X Ray Irradiation
    International Journal of Nanomedicine, 2016
    Co-Authors: Xi Liu, Yan Liu, Xiaodong Jin, Pengcheng Zhang, Xiaogang Zheng, Weiqiang Chen
    Abstract:

    Reductive drug-functionalized gold nanoparticles (AuNPs) have been proposed to enhance the damage of X-Rays to cells through improving hydroXyl radical production by secondary electrons. In this work, polyethylene glycol-capped AuNPs were conjugated with tirapazamine (TPZ) moiety, and then thioctyl TPZ (TPZs)-modified AuNPs (TPZs-AuNPs) were synthesized. The TPZs-AuNPs were characterized by transmission electron microscopy, ultraviolet-visible spectra, dynamic light scattering, and inductively coupled plasma mass spectrometry to have a size of 16.6±2.1 nm in diameter and a TPZs/AuNPs ratio of ~700:1. In contrast with PEGylated AuNPs, the as-synthesized TPZs-AuNPs eXhibited 20% increment in hydroXyl radical production in water at 2.0 Gy, and 19% increase in sensitizer enhancement ratio at 10% survival fraction for human hepatoma HepG2 cells under X-Ray Irradiation. The production of reactive oXygen species in HepG2 cells eXposed to X-Rays in vitro demonstrated a synergistic radiosensitizing effect of AuNPs and TPZ moiety. Thus, the reductive drug-conjugated TPZs-AuNPs as a kind of AuNP radiosensitizer with low gold loading provide a new strategy for enhancing the efficacy of radiation therapy.

David Stanley - One of the best experts on this subject based on the ideXlab platform.

  • larval X Ray Irradiation influences protein eXpression in pupae of the oriental fruit fly bactrocera dorsalis
    Archives of Insect Biochemistry and Physiology, 2016
    Co-Authors: Chiou Ling Chang, Cynthia L Goodman, Joseph Ringbauer, Scott M Geib, David Stanley
    Abstract:

    The sterile insect technique (SIT) was developed to eradicate the new world screwworm from the southern United States and MeXico, and became a component of many area-wide integrated pest management programs, particularly useful in managing tephritid fruit flies. SIT is based on the idea of rearing and sterilizing male pests, originally by ionizing radiation, and then releasing into field, where they compete for and mate with wild females. Mating with sterile males leads to reduced fecundity to lower pest populations. There are concerns with the use and distribution of radioisotopes for SIT programs, which have led to developing X-Ray Irradiation protocols to sterilize insects. We considered the possibility that X-Ray Irradiation eXerts sublethal impacts aside form sterilizing insects. Such effects may not be directly observable, which led us to the hypothesis that X-Ray Irradiation in one life stage creates alterations in biological fitness and protein eXpression in the subsequent stage. We tested our hypothesis by irradiating larvae of Bactrocera dorsalis. There are two major points. One, eXposing larvae to X-Ray treatments led to reduced adult emergence, fecundity, fertility, and flight capacity from the corresponding pupae and emerged adults. Two, the X-Ray treatments led to substantial eXpression changes in 27 pupal proteins. We assorted the 67 spots representing these proteins into three groups, metabolism, development, and structure. Our interpretation is these X-Ray induced changes in biological performance and protein eXpression indicate their adult counterparts may be disabled in their abilities to successfully compete for and mate wild females in native habitats.

  • pupal X Ray Irradiation influences protein eXpression in adults of the oriental fruit fly bactrocera dorsalis
    Journal of Insect Physiology, 2015
    Co-Authors: Chiou Ling Chang, Cynthia L Goodman, Joseph Ringbauer, Scott M Geib, Maryann Villalun, David Stanley
    Abstract:

    The oriental fruit fly, Bactrocera dorsalis, is a pest of fruit in the Asia–Pacific region and also, due to quarantine restrictions, a threat to California fruit production. Area-wide suppression of B. dorsalis integrated several approaches including the sterile insect technique (SIT). SIT involves eXposing juveniles to gamma radiation and releasing sterile males in substantial numbers, where they successfully compete for wild females. The resulting infertile eggs lead to reduction of the pest populations. Although these protocols are well documented, arising issues about the international transport and distribution of radioactive products is creating difficulties in use of radioactive sources for sterilizing radiation. This led to a shift toward use of X-Ray Irradiation, which also sterilizes male and female insects. However, use of X-Ray technologies is in its infancy and there is virtually no information on the effects of Irradiation, other than sterilization, at the physiological and molecular levels of fruit fly biology. We posed the hypothesis that sterilizing male oriental fruit flies via radiation treatment also influences protein eXpression in the flies. We found that eXposing pupae to X-Ray Irradiation impacted eXpression of 26 proteins in adult females and 31 proteins in adult males. Seven proteins (glyceraldehyde-3-phosphate dehydrogenase, fructose-bisphosphate aldolase, larval cuticle protein 2, sarcoplasmic calcium-binding protein alpha-B and A chains, general odorant-binding protein 99b, polyubiquitin, and protein disulfide-isomerase) were impacted in both seXes. Some of the proteins act in central energy-generating and in pheromone-signal processing pathways; we infer that males sterilized by X-Ray Irradiation may be enfeebled in their ability to compete with wild males for females in nature.

Ming Chen - One of the best experts on this subject based on the ideXlab platform.

  • synergistic effect of paf inhibition and X Ray Irradiation in non small cell lung cancer cells
    Strahlentherapie Und Onkologie, 2021
    Co-Authors: Yamei Chen, Ying Jin, Hangjie Ying, Peng Zhang, Ming Chen
    Abstract:

    PURPOSE Proliferating cell nuclear antigen-associated factor (PAF) is involved in cancer cell growth and associated with cell death induced by ultraviolet (UV) radiation. However, the contribution of PAF to radiotherapy sensitivity in non-small cell lung cancer (NSCLC) is unknown. The aim of this study was to investigate the relationship between PAF eXpression and radiotherapy response in NSCLC. METHODS Associations between PAF eXpression and patient survival outcomes were evaluated using publicly available online gene eXpression datasets. RNA interference was performed to knockdown PAF eXpression in the NSCLC cells. The effects of PAF knockdown on cell proliferation, migration, apoptosis, DNA damage, and activation of MEK/ERK and Wnt/β-catenin signaling pathways following XRay Irradiation were evaluated in vitro. RESULTS PAF was found to be overeXpressed in lung cancer tissues compared with normal samples, and elevated PAF eXpression was significantly correlated with inferior patient survival. In vitro, knockdown of PAF inhibited cell proliferation, cell apoptosis, and migration induced by XRay Irradiation. Moreover, XRay-induced intracellular DNA strand damage was more obvious following PAF knockdown. Additionally, PAF knockdown inhibited activation of the MEK/ERK and Wnt/β-catenin signaling pathways in XRay-irradiated A549 cells. CONCLUSION These data demonstrate that reduced eXpression of PAF enhances radiosensitivity in NSCLC cells. Mechanistically, inhibition of the MEK/ERK and Wnt/β-catenin signaling pathways caused by PAF interference may lead to impaired cell function and enhance sensitivity to XRays. Targeting PAF may therefore serve as a potential therapeutic strategy to increase the efficiency of radiotherapy in NSCLC patients, ultimately improving patient survival.

  • synergistic effect of paf inhibition and X Ray Irradiation in non small cell lung cancer cells
    Strahlentherapie Und Onkologie, 2021
    Co-Authors: Yamei Chen, Ying Jin, Hangjie Ying, Peng Zhang, Ming Chen
    Abstract:

    Proliferating cell nuclear antigen-associated factor (PAF) is involved in cancer cell growth and associated with cell death induced by ultraviolet (UV) radiation. However, the contribution of PAF to radiotherapy sensitivity in non-small cell lung cancer (NSCLC) is unknown. The aim of this study was to investigate the relationship between PAF eXpression and radiotherapy response in NSCLC. Associations between PAF eXpression and patient survival outcomes were evaluated using publicly available online gene eXpression datasets. RNA interference was performed to knockdown PAF eXpression in the NSCLC cells. The effects of PAF knockdown on cell proliferation, migration, apoptosis, DNA damage, and activation of MEK/ERK and Wnt/β-catenin signaling pathways following XRay Irradiation were evaluated in vitro. PAF was found to be overeXpressed in lung cancer tissues compared with normal samples, and elevated PAF eXpression was significantly correlated with inferior patient survival. In vitro, knockdown of PAF inhibited cell proliferation, cell apoptosis, and migration induced by XRay Irradiation. Moreover, XRay-induced intracellular DNA strand damage was more obvious following PAF knockdown. Additionally, PAF knockdown inhibited activation of the MEK/ERK and Wnt/β-catenin signaling pathways in XRay-irradiated A549 cells. These data demonstrate that reduced eXpression of PAF enhances radiosensitivity in NSCLC cells. Mechanistically, inhibition of the MEK/ERK and Wnt/β-catenin signaling pathways caused by PAF interference may lead to impaired cell function and enhance sensitivity to XRays. Targeting PAF may therefore serve as a potential therapeutic strategy to increase the efficiency of radiotherapy in NSCLC patients, ultimately improving patient survival.

Y Hwu - One of the best experts on this subject based on the ideXlab platform.

  • optimizing the size and surface properties of polyethylene glycol peg gold nanoparticles by intense X Ray Irradiation
    Journal of Physics D, 2008
    Co-Authors: Changhai Wang, Chijen Liu, Y Hwu, Tzuen Hua, Chengliang Wang, Judy M Obliosca, Kyuho Lee, Chungshi Yang, R S Liu, Hongming Lin
    Abstract:

    The polyethylene glycol (PEG) modified gold nanoparticle compleX was synthesized by a one-solution synchrotron X-Ray Irradiation method. The impact on the structure and morphology of the gold nanoparticles of process parameters such as the PEG molecular weight, the PEG/gold molar ratio and the X-Ray dosage were investigated. The size of PEG modified gold particles was found to decrease with increasing PEG addition and X-Ray dosage. With the capability to monitor the absorption spectra in situ during the fast synthesis process, this opens the way to accurate control of the size and distribution. PEG chains with an intermediate length (MW6000) were found optimal for size control and colloidal stability in biologically relevant media. Our X-Ray synthesized PEG-gold nanoparticles could find interesting applications in nanoparticle-enhanced X-Ray tumour imaging and therapy.

  • enhanced X Ray Irradiation induced cancer cell damage by gold nanoparticles treated by a new synthesis method of polyethylene glycol modification
    Nanotechnology, 2008
    Co-Authors: Chijen Liu, Changhai Wang, Chiachi Chien, Tsungyeh Yang, Shintai Chen, Weihua Leng, Chengfeng Lee, Kuenho Lee, Y Hwu
    Abstract:

    We eXplored a very interesting gold nanoparticle system?pegylated gold in colloidal solution?and analyzed its uptake by mice colorectal adenocarcinoma CT26 tumor cells and the impact on the cell's response to X-Ray Irradiation. We found that eXposure to polyethylene glycol (PEG) modified ('pegylated') 4.7 ? 2.6?nm gold nanoparticles synthesized by a novel synchrotron-based method enhances the response of CT26 cells to X-Ray Irradiation. Transmission electron microscopy (TEM) and confocal microscopy revealed that substantial amounts of such nanoparticles are taken up and absorbed by the cells and this conclusion is supported by quantitative induced coupled plasma (ICP) results. Standard tests indicated that the internalized particles are highly biocompatible but strongly enhance the cell damage induced by X-Ray Irradiation. Synchrotron radiation Fourier transform infrared (SR-FTIR) spectromicroscopy analyzed the chemical aspects of this phenomenon: the appearance of C = O stretching bond spectral features could be used as a marker for cell damage and confirmed the enhancement of the radiation-induced toXicity for cells.

  • aqueous gold nanosols stabilized by electrostatic protection generated by X Ray Irradiation assisted radical reduction
    Materials Chemistry and Physics, 2007
    Co-Authors: Changhai Wang, Chijen Liu, Chiachi Chien, Tsungyeh Yang, Weihua Leng, Y Hwu, Tzuen Hua
    Abstract:

    Reductant, stabilizer-free colloidal gold solutions were fabricated by a new room-temperature synchrotron X-Ray Irradiation method. The influence of process parameters such as the pH value and the eXposure time on the structure of gold nanoparticles was investigated. The mechanisms underlying the X-Ray-triggered reduction of gold ions and the formation of gold clusters are discussed in detail. The X-Ray Irradiation derived highly concentrated gold nanoparticles are readily to be re-dispersed and possess suitable colloidal stability within cellular environment. The characterization included a study of the possible cytotoXicity for the EMT-6 tumor cell line: the negative results indicate that the gold clusters produced with our approach are biocompatible.

Darius M Moshfeghi - One of the best experts on this subject based on the ideXlab platform.

  • 16 gy low voltage X Ray Irradiation followed by as needed ranibizumab therapy for age related macular degeneration 12 month outcomes of a radiation first strategy
    British Journal of Ophthalmology, 2012
    Co-Authors: Andrew A Moshfeghi, Virgilio Moralescanton, Hugo Quirozmercado, Raul Velezmontoya, Alicia Zavalaayala, Eugene M Shusterman, Peter K Kaiser, Steven R Sanislo, Michael Gertner, Darius M Moshfeghi
    Abstract:

    Background and objective To describe ‘radiation-first’ combination treatment with a non-invasive, low-voltage X-Ray Irradiation system followed by as needed ranibizumab for neovascular age-related macular degeneration (AMD). Study design and methods Phase I study of non-invasive, low-voltage 16 Gy X-Ray Irradiation delivered in three beams via the inferior pars plana in patients with active neovascular AMD. Ranibizumab was administered as needed per protocol. Patients were followed monthly for safety and efficacy over 12 months. Results 13 patients were enrolled and completed 12 months follow-up. Safety was good with no serious ocular/non-ocular adverse events or radiation-related ocular complications. 11 patients lost Conclusions After 12 months, non-invasive, low-voltage X-Ray Irradiation with as needed ranibizumab rescue therapy demonstrated good safety with a visual acuity stabilising effect and reduction in retinal thickness in patients with neovascular AMD.

  • 24 gy low voltage X Ray Irradiation with ranibizumab therapy for neovascular amd 6 month safety and functional outcomes
    Ophthalmic Surgery Lasers & Imaging, 2012
    Co-Authors: Virgilio Morales Canton, Andrew A Moshfeghi, Hugo Quirozmercado, Raul Velezmontoya, Eugene M Shusterman, Peter K Kaiser, Steven R Sanislo, Michael Gertner, Miriam J Lopezmiranda, Darius M Moshfeghi
    Abstract:

    BACKGROUND AND OBJECTIVE To describe the 6-month safety and preliminary efficacy outcomes of the use of 24-Gy radiation with intravitreal ranibizumab for patients with neovascular age-related macular degeneration (AMD). PATIENTS AND METHODS A single treatment of a non-invasive, eXternally delivered low-voltage X-Ray Irradiation at a dose of 24 Gy was administered in one session through three locations in the inferior pars plana in a consecutive series of patients with neo-vascular AMD (treatment naive and previously treated). Optical coherence tomography (OCT) and Early Treatment Diabetic Retinopathy Study (ETDRS) visual acuity eXaminations were performed at 1 week, 1 month, and monthly thereafter with quarterly fluorescein angiography. RESULTS Nineteen patients completed 6 months of follow-up. There was no evidence of radiation retinopathy, optic neuropathy, or cataract. The mean baseline ETDRS score was 38.3 ± 19.5 letters. At 6 months, the corresponding ETDRS score was 44.7 ± 16.8 letters. At 6 months, the mean change in visual acuity was 6.4 ± 9.8 ETDRS letters. Patients received an average of 0.4 additional ranibizumab injections following the initial two mandated injections. CONCLUSION A single treatment of eXternal 24-Gy low-voltage X-Ray therapy in conjunction with ranibizumab demonstrated an overall improvement in visual acuity in patients with neovascular AMD at 6 months, with no radiation-related adverse effects.

  • 16 gy low voltage X Ray Irradiation followed by as needed ranibizumab therapy for amd 6 month outcomes of a radiation first strategy
    Ophthalmic Surgery Lasers & Imaging, 2011
    Co-Authors: Andrew A Moshfeghi, Hugo Quirozmercado, Raul Velezmontoya, Eugene M Shusterman, Peter K Kaiser, Steven R Sanislo, Michael Gertner, Virgilio Morales Canton, Miriam J Lopezmiranda, Darius M Moshfeghi
    Abstract:

    BACKGROUND AND OBJECTIVE To describe the effect of a "radiation-first" combination treatment strategy for neovascular age-related macular degeneration (AMD) with ranibizumab rescue therapy. PATIENTS AND METHODS Non-invasive, eXternally delivered low-voltage X-Ray Irradiation at a dose of 16 Gy was given in a single session through three locations in the inferior pars plana in a consecutive series of patients with neovascular AMD. Ranibizumab was administered according to prospectively determined criteria. RESULTS Thirteen patients completed a 6-month follow-up. All patients lost 15 or fewer ETDRS letters, 7 gained 0 or more ETDRS letters, and 0 gained more than 15 ETDRS letters. Patients received a total of 15 ranibizumab injections following X-Ray Irradiation at baseline. Two patients received no ranibizumab injections, seven patients received 1 injection, and four patients received 2 injections. CONCLUSION Low-voltage X-Ray treatment followed by ranibizumab rescue demonstrates an independent visual acuity stabilizing effect for patients with wet AMD.

  • 16 gy low voltage X Ray Irradiation with ranibizumab therapy for amd 6 month safety and functional outcomes
    Ophthalmic Surgery Lasers & Imaging, 2011
    Co-Authors: Virgilio Morales Canton, Andrew A Moshfeghi, Hugo Quirozmercado, Raul Velezmontoya, Eugene M Shusterman, Peter K Kaiser, Steven R Sanislo, Michael Gertner, Miriam J Lopezmiranda, Darius M Moshfeghi
    Abstract:

    Background and objective To describe the 6-month safety and preliminary efficacy outcomes of the use of 16-Gy radiation with intravitreal ranibizumab for patients with neovascular age-related macular degeneration (AMD). Patients and methods A single treatment of a non-invasive, eXternally delivered low-voltage 16-Gy X-Ray Irradiation was administered in one session through three locations in the inferior pars plana. Optical coherence tomography (OCT) and Early Treatment Diabetic Retinopathy Study (ETDRS) visual acuity (VA) eXaminations were performed at 1 week, 1 month, and monthly thereafter, with quarterly fluorescein angiography (FA). After the two initial ranibizumab injections, subsequent injections were administered according to the following criteria: VA decline of 10 ETDRS letters compared with baseline, increase of 100-μm central foveal thickness on OCT compared with baseline, the development of new submacular hemorrhage, and the development of a new area of classic choroidal neovascularization on FA. Results Twenty-siX patients completed a 6-month follow-up. There was no evidence of radiation retinopathy, optic neuropathy, or cataract. The mean baseline ETDRS score was 46.6 letters (range: 5 to 80; standard deviation [SD]: 21.5). At 6 months, the corresponding ETDRS score was 55.6 letters (range: 25 to 80; SD: 18.9) and the mean change in VA was 9.5 ETDRS letters (SD: 10.3). On responder analysis, 96% lost 15 or fewer ETDRS letters, 81% gained 0 or more ETDRS letters, and 50% gained 15 or more ETDRS letters. Patients received a total of 13 ranibizumab injections following two initial injections. At 6 months, patients received an average of 0.5 additional injections following the initial two mandated injections. Conclusion A single treatment of eXternally applied, non-invasive 16-Gy low-voltage X-Ray therapy in conjunction with ranibizumab demonstrated an overall improvement of VA in patients with neovascular AMD at 6 months with no radiation-related adverse effects.

  • stereotactic low voltage X Ray Irradiation for age related macular degeneration
    British Journal of Ophthalmology, 2011
    Co-Authors: Darius M Moshfeghi, Peter K Kaiser, Michael Gertner
    Abstract:

    The IRay stereotactic low-voltage X-Ray Irradiation treatment system for age-related macular degeneration consists of a low voltage X-Ray tube, an eye tracking system, a robotically controlled delivery system, a coupling device to facilitate tracking and stabilisation, a graphical user interface and gating software. Low-voltage X-Rays are delivered in a series of three spots to the macula in a non-invasive manner through the inferior pars plana. These beams are designed to overlap on the centre of the macula. Each beam delivers one-third of the total dose, such that the total macula dose is three times an individual beam's dose. The device is designed to run off standard domestic electrical power, and no special shielding is necessary for the room. This system has been validated in Monte Carlo simulations, human cadaver eye studies, pre-clinical animal studies and in a phase I clinical trial.