Journal of Radiation Research
Online ISSN : 1349-9157
Print ISSN : 0449-3060
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Volume 52, Issue 1
Displaying 1-18 of 18 articles from this issue
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Regular Papers
  • Effect of Sunitinib Combined with Ionizing Radiation on Endothelial Cells
    Hai-Ping ZHANG, Koichi TAKAYAMA, Bo SU, Xiao-dong JIAO, Rui LI, Jie-Ju ...
    2011 Volume 52 Issue 1 Pages 1-8
    Published: 2011
    Released on J-STAGE: January 29, 2011
    Advance online publication: December 24, 2010
    DOIhttps://doi.org/10.1269/jrr.10013
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    The aims of present study were to evaluate the efficacy of combining sunitinib with ionizing radiation (IR) on endothelial cells in vitro and in vivo. Human umbilical vein endothelial cells (HUVECs) were exposed to IR with or without sunitinib pretreatment. Apoptosis assay and cell cycle distribution were analyzed by flow cytometry. Clonogenic survival assay at 3 Gy dose with or without sunitinib was performed. The activity of phosphatidylinositol 3-kinase (PI3K)/Akt signal pathway was detected by Western immunoblot. Lewis lung carcinoma mouse model was built to examine the effect of combination therapy on endothelial cells in vivo. Microvasculature changes were detected by immunohistochemistry using anti-CD31 antibody. Our results showed combination therapy of sunitinib and IR significantly increased apoptosis of endothelial cells and inhibited colony formation compared to sunitinib or radiotherapy alone. It also resulted in cell cycle redistribution (decreasing cells in S phase and increasing cells in G2/M phase). The activity of PI3K/Akt signal pathway was inhibited, which could be the potential mechanisms that account for the enhanced radiation response induced by sunitinib. In vivo analysis showed that combination therapy significantly decreased microvasculature formation. The results demonstrated that combination therapy of sunitinib and IR has the potential to increase the cytotoxic effects on endothelial cells.
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  • Impact of Incomplete Plan to Treatment Results of Concurrent Weekly Cisplatin and Radiotherapy in Locally Advanced Cervical Cancer
    Ekkasit THARAVICHITKUL, Attapol PINITPATCHARALERD, Vicharn LORVIDHAYA, ...
    2011 Volume 52 Issue 1 Pages 9-14
    Published: 2011
    Released on J-STAGE: January 29, 2011
    Advance online publication: December 24, 2010
    DOIhttps://doi.org/10.1269/jrr.10021
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    To evaluate the efficacy of incomplete treatment protocols of cisplatin in concurrent chemoradiation for locally advanced cervical carcinoma. This retrospective study was performed in 165 consecutively treated patients with locally advanced cervical cancer who received a weekly cisplatin regimen. The number of weekly cisplatin cycles of each patient was recorded and used to discriminate between patients. Local control, disease free survival, distant metastasis-free survival, and toxicities were calculated using the software package SPSS version 15.0. Ninety-two patients (55%) completed the planned protocol of six cycles of weekly cisplatin. With the median follow-up time of 38.2 months, the 3-year local control rate differed significantly in the two patient groups (95.4% of 6 cycles versus 84.8% of < 6 cycles; p = 0.028). No statistical significance was observed for disease-free survival (74.6% versus 74.5%; p = 0.22) and distant metastasis-free survival (76.5% vs. 75.7%; p = 0.88). In conclusion, the plan completion of concurrent cisplatin with radiotherapy was responsible for better local control. However, differences in disease-free survival and distant metastasis-free survival were not statistical significant.
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  • Pulse Radiolysis Study on Free Radical Scavenger Edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one). 2: A Comparative Study on Edaravone Derivatives
    Kuniki HATA, Mingzhang LIN, Yosuke KATSUMURA, Yusa MUROYA, Haiying FU, ...
    2011 Volume 52 Issue 1 Pages 15-23
    Published: 2011
    Released on J-STAGE: January 29, 2011
    Advance online publication: December 02, 2010
    DOIhttps://doi.org/10.1269/jrr.10060
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    A comparative study using the pulse radiolysis technique was carried out to investigate transient absorption spectra and rate constants for the reactions of •OH and N3• with edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one) and its four analogue compounds, 1,3-dimethyl-2-pyrazolin-5-one, 3-methyl-1-(pyridin-2-yl)-2-pyrazolin-5-one, 1-phenyl-3-trifluoromethyl-2-pyrazolin-5-one and 1-(4-chlorophenyl)-3-methyl-2-pyrazolin-5-one. The results showed that, unlike reaction mechanisms previously proposed, the phenyl group of edaravone played an important role in the reaction with •OH and OH adducts to the phenyl group were formed. Quantum chemical calculations also strongly supported this attribution and suggested that the most favorable site for attacks by •OH is the ortho position of the phenyl group. Moreover, the rate constants for the reactions of edaravone and its analogues towards •OH and N3• were about 8.0 × 109, and 4.0 × 109 dm3 mol–1 s–1, respectively. Edaravone displayed higher reactivity compared to the others, in contrast to a previous report in which 3-methyl-1-(pyridin-2-yl)-2-pyrazolin-5-one showed the highest reactivity towards •OH.
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  • Stereotactic Body Radiation Therapy for Head and Neck Tumor: Disease Control and Morbidity Outcomes
    Naohiro KODANI, Hideya YAMAZAKI, Takuji TSUBOKURA, Hiroya SHIOMI, Kana ...
    2011 Volume 52 Issue 1 Pages 24-31
    Published: 2011
    Released on J-STAGE: January 29, 2011
    Advance online publication: November 27, 2010
    DOIhttps://doi.org/10.1269/jrr.10086
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    We evaluated the efficacy and safety of stereotactic body radiation therapy (SBRT) for patients with head and neck tumors. From April 2005 through April 2008, 34 patients with head and neck tumors were treated with CyberKnife SBRT. Twenty-one of them had prior radiotherapy. Treatment sites were orbit (n = 7), cervical lymph nodes (n = 6), nasopharynx (n = 5), oropharynx (n = 4) and others (n = 12). The prescribed dose ranged from 19.5 to 42 Gy (median, 30 Gy) in 3–8 fractions for consecutive days. The target volume ranged from 0.7 to 78.1 cm3 (median, 11.6 cm3). The median follow-up was 16 months. Treatment was well tolerated without significant acute complications in any cases. Complete response rate and partial response rate were 32.4% and 38.6%, respectively. The overall survival rates were 70.6% and 58.3% at 12 and 24 months, respectively. The overall survival was better in patients without prior radiotherapy within the previous 24 months or in case of smaller target volume. Six patients suffered severe late complications. All these patients had prior radiotherapy, and 2 of them developed massive hemorrhage in the pharynx and both died of this complication 5 and 28 months, respectively, after SBRT. Our preliminary results suggest that SBRT is an effective treatment modality for head and neck tumors. However, re-irradiation has significant risk of severe and even fatal late complications in the form of necrosis and hemorrhage in re-irradiated areas.
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  • Vitamin E-Deficiency Did Not Exacerbate Partial Skin Reactions in Mice Locally Irradiated with X-rays
    Cuiping CHI, Daisuke HAYASHI, Masato NEMOTO, Minako NYUI, Shiro URANO, ...
    2011 Volume 52 Issue 1 Pages 32-38
    Published: 2011
    Released on J-STAGE: January 29, 2011
    DOIhttps://doi.org/10.1269/jrr.10042
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    We previously showed that free radicals and oxidative stress are involved in radiation-induced skin reactions. Since vitamin E (VE) is a particularly important lipophilic antioxidant, VE-deficient mice were used to examine its effects on radiation-induced skin damage. The VE content of the skin was reduced to one fourth of levels of normal mice. Neither the time of onset nor the extent of the reactions quantified with a scoring system differed between normal and VE-deficient mice after local X-irradiation (50 Gy). Similarly, there was no difference in the levels of the ascorbyl radical between the groups, although they were higher in irradiated skin than non-irradiated skin. X-irradiation increased the amount of Bax protein in the skin of normal mice both in the latent and acute inflammatory stages, time- and dose-dependently. The increase was associated with an increase in cytochrome c in the cytosolic fraction, indicating that apoptosis was also promoted by the irradiation. The increase in Bax protein correlated well with the thickness of the skin. Although a deficiency in VE should lower resistance to free radicals in the mitochondrial membrane and thus enhance radiation-induced Bax expression and apoptosis, it actually attenuated the increase in Bax protein caused by irradiation.
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  • Gene Silencing of Tead3 Abrogates Radiation-induced Adaptive Response in Cultured Mouse Limb Bud Cells
    Guillaume VARES, Bing WANG, Kaoru TANAKA, Yi SHANG, Keiko TAKI, Tetsuo ...
    2011 Volume 52 Issue 1 Pages 39-46
    Published: 2011
    Released on J-STAGE: January 29, 2011
    DOIhttps://doi.org/10.1269/jrr.10101
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    There is a crucial need to better understand the effects of low-doses of ionizing radiation in fetal models. Radiation-induced adaptive response (AR) was described in mouse embryos pre-exposed in utero to low-doses of X-rays, which exhibited lower apoptotic levels in the limb bud. We previously described AR-specific gene modulations in the mouse embryo. In this study, we evaluated the role of three candidate genes in the apoptotic AR in a micromass culture of limb bud cells: Csf1, Cacna1a and Tead3. Gene silencing of these three genes abrogated AR. Knowing that TEAD3 protein levels are significantly higher in adapted cells and that YAP/TAZ/TEAD are involved in the control of cell proliferation and apoptosis, we suggest that modulation of Tead3 could play a role in the induction of AR in our model, seen as a reduction of radiation-induced apoptosis and a stimulation of proliferation and differentiation in limb bud cells.
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  • Concurrent Chemoradiotherapy with S-1 as First-line Treatment for Patients with Oropharyngeal Cancer
    Kayoko OHNISHI, Yoshiyuki SHIOYAMA, Katsumasa NAKAMURA, Torahiko NAKAS ...
    2011 Volume 52 Issue 1 Pages 47-53
    Published: 2011
    Released on J-STAGE: January 29, 2011
    Advance online publication: December 24, 2010
    DOIhttps://doi.org/10.1269/jrr.10081
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    Purpose: S-1 is an oral fluoropyrimidine. The purpose of this study was to review the clinical outcomes of S-1 with concurrent radiotherapy for patients with oropharyngeal cancer. Materials and Methods: Between 2002 and 2007, 38 patients with oropharyngeal cancer treated concurrently with S-1 and definitive radiotherapy were reviewed. The clinical stage was Stage I in 4 patients, Stage II in 7, Stage III in 7, and Stage IV in 20. S-1 was administered orally twice daily for 4 consecutive weeks followed by a 2-week drug withdrawal. The initial dose of S-1 was 65 mg/m2/day. All patients were treated using three-dimensional conformal radiotherapy with a median total dose of 65.1 Gy (range, 60.0–71.0 Gy). Clinical outcomes and major acute toxicities were analyzed based on medical records and clinical follow-up. Results: With a median follow-up time of 33 months, the 3-year estimates of local-regional control, distant metastases-free survival, disease-free survival, and overall survival for all patients were 75%, 80%, 65%, and 80%, respectively. The 3-year estimates of local-regional control according to stage were 100% for Stages I and II, 86% for Stage III, and 56% for Stage IV. The rate of ≥ Grade 3 acute mucositis was 32%, and the rate of ≥ Grade 3 hematological toxicities was 8%. No other severe toxicities were observed. Conclusions: Concurrent chemoradiotherapy with S-1 was found to be effective, especially for early disease. The treatment-related toxicities were acceptable, and the incidence of myelotoxicity was low. Further study must be carried out to compare with other chemotherapy regimens.
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  • Intracavitary Combined with CT-guided Interstitial Brachytherapy for Locally Advanced Uterine Cervical Cancer: Introduction of the Technique and a Case Presentation
    Masaru WAKATSUKI, Tatsuya OHNO, Daisaku YOSHIDA, Shin-ei NODA, Jun-ich ...
    2011 Volume 52 Issue 1 Pages 54-58
    Published: 2011
    Released on J-STAGE: January 29, 2011
    DOIhttps://doi.org/10.1269/jrr.10091
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    We report a new technique of brachytherapy consisting of intracavitary combined with computed tomography (CT)-guided interstitial brachytherapy for locally advanced cervical cancer. A Fletcher-Suit applicator and trocar point needles were used for performing high-dose rate brachytherapy under in-room CT guidance. First, a tandem and ovoids were implanted into the patient's vagina and uterus by conventional brachytherapy method. Based on clinical examination and MRI/CT imaging, operating radiation oncologists decided the positions of insertion in the tumor and the depth of the needles from the upper surface of the ovoid. Insertion of the needle applicator was performed from the vaginal vault inside the ovoid within the tumor under CT guidance. In treatment planning, dwell positions and time adaptations within the tandem and ovoids were performed first for optimization based on the Manchester system, and then stepwise addition of dwell positions within the needle was continued. Finally, dwell positions and dwell weights were manually modified until dose-volume constraints were optimally matched. In our pilot case, the dose of D90 to high-risk clinical target volume was improved from 3.5 Gy to 6.1 Gy by using our hybrid method on the dose-volume histogram. D1cc of the rectum, bladder and sigmoid colon by our hybrid method was 4.8 Gy, 6.4 Gy and 3.5 Gy, respectively. This method consists of advanced image-guided brachytherapy that can be performed safely and accurately. This approach has the potential of increasing target coverage, treated volume, and total dose without increasing the dose to organs at risk.
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  • Microdosimetric Approach to NIRS-defined Biological Dose Measurement for Carbon-ion Treatment Beam
    Yuki KASE, Tatsuaki KANAI, Makoto SAKAMA, Yuji TAMESHIGE, Takeshi HIMU ...
    2011 Volume 52 Issue 1 Pages 59-68
    Published: 2011
    Released on J-STAGE: January 29, 2011
    Advance online publication: December 13, 2010
    DOIhttps://doi.org/10.1269/jrr.10062
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    The RBE-weighted absorbed dose, called "biological dose," has been routinely used for carbon-ion treatment planning in Japan to formulate dose prescriptions for treatment protocols. This paper presents a microdosimetric approach to measuring the biological dose, which was redefined to be derived from microdosimetric quantities measured by a tissue-equivalent proportional counter (TEPC). The TEPC was calibrated in 60Co gamma rays to assure a traceability of the TEPC measurement to Japanese standards and to eliminate the discrepancies among matching counters. The absorbed doses measured by the TEPC were reasonably coincident with those measured by a reference ionization chamber. The RBE value was calculated from the microdosimetric spectrum on the basis of the microdosimetric kinetic model. The biological doses obtained by the TEPC were compared with those prescribed in the carbon-ion treatment planning system. We found that it was reasonable for the measured biological doses to decrease with depth around the rear SOBP region because of beam divergence, scattering effect, and fragmentation reaction. These results demonstrate that the TEPC can be an effective tool to assure the radiation quality in carbon-ion radiotherapy.
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  • Multi-institutional Retrospective Analysis of the Inhomogeneity Correction for Radiation Therapy of Lung Cancer
    Hideyuki MIZUNO, Hiroyuki OKAMOTO, Miyoko FUKUOKA, Yuji HANYU, Masahik ...
    2011 Volume 52 Issue 1 Pages 69-74
    Published: 2011
    Released on J-STAGE: January 29, 2011
    Advance online publication: December 24, 2010
    DOIhttps://doi.org/10.1269/jrr.10066
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    The purpose of this work is to retrospectively analyze the effect of the inhomogeneity correction using clinically treated plan of stage III non-small-cell lung cancer within multiple institutions in Japan. Twenty-five patients among five facilities of radiation therapy were registered for this study. The isocenter dose or D95 of PTV or other important values were compared with and without an inhomogeneity correction using model-based algorithm. The differences in isocenter dose were 4% average and 10% maximum for the first Anterior-Posterior opposed field plan to 40 Gy and 6% average and 11% maximum for the off-cord boost oblique field plan of 20 Gy. The differences in D95 dose were 1% average and 9% maximum for the first plan and 1% average and 6% maximum for the boost plan. D95 prescription seemed to be a superior method; however, its reliability depends on each clinical case. Additionally, maximum dose, minimum dose and mean dose for both the primary tumor and the metastatic lymph node were analyzed, and the minimum dose had the most impressive results. In some cases, the target volume had unintended underdose of more than 10%. Finally, an analysis of the organ at risk was added, and this showed no meaningful differences for the V20 of the lung and the maximum dose of the spinal cord. These results provide a standard for the effects of the inhomogeneity correction.
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  • Relation between Lineal Energy Distribution and Relative Biological Effectiveness for Photon Beams according to the Microdosimetric Kinetic Model
    Hiroyuki OKAMOTO, Tatsuaki KANAI, Yuki KASE, Yoshitaka MATSUMOTO, Yosh ...
    2011 Volume 52 Issue 1 Pages 75-81
    Published: 2011
    Released on J-STAGE: January 29, 2011
    Advance online publication: December 13, 2010
    DOIhttps://doi.org/10.1269/jrr.10073
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    Our cell survival data showed the obvious dependence of RBE on photon energy: The RBE value for 200 kV X-rays was approximately 10% greater than those for mega-voltage photon beams. In radiation therapy using mega-voltage photon beams, the photon energy distribution outside the field is different with that in the radiation field because of a large number of low energy scattering photons. Hence, the RBE values outside the field become greater. To evaluate the increase in RBE, the method of deriving the RBE using the Microdosimetric Kinetic model (MK model) was proposed in this study. The MK model has two kinds of the parameters, tissue-specific parameters and the dose-mean lineal energy derived from the lineal energy distributions measured with a Tissue-Equivalent Proportional Counter (TEPC). The lineal energy distributions with the same geometries of the cell irradiations for 200 kV X-rays, 60Co γ-rays, and 6 MV X-rays were obtained with the TEPC and Monte Carlo code GEANT4. The measured lineal energy distribution for 200 kV X-rays was quite different from those for mega-voltage photon beams. The dose-mean lineal energy of 200 kV X-rays showed the greatest value, 4.51 keV/μm, comparing with 2.34 and 2.36 keV/μm for 60Co γ-rays and 6 MV X-rays, respectively. By using the results of the TEPC and cell irradiations, the tissue-specific parameters in the MK model were determined. As a result, the RBE of the photon beams (yD: 2~5 keV/μm) in arbitrary conditions can be derived by the measurements only or the calculations only of the dose-mean lineal energy.
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  • Fractionated Stereotactic Radiation Therapy for Orbital Optic Nerve Sheath Meningioma – a Single Institution Experience and a Short Review of the Literature
    Roberto PACELLI, Laura CELLA, Manuel CONSON, Fausto TRANFA, Diego STRI ...
    2011 Volume 52 Issue 1 Pages 82-87
    Published: 2011
    Released on J-STAGE: January 29, 2011
    DOIhttps://doi.org/10.1269/jrr.10139
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    Optic nerve sheath meningioma (ONSM) is a rare orbital tumor that generally induces a slow progressive visual loss in affected patients. Radiotherapy (RT) has currently become the first choice to treat ONSM. In this study our experience in ONSM treatment with fractionated stereotactic radiotherapy (FSRT) is reported. Five patients with diagnosis of orbital ONSM were treated between April 2007 and December 2009 at the Radiation Oncology department of our institution. All patients underwent history and physical, and ophthalmic examinations. Orbital MRI was performed before and 6 weeks after treatment; thereafter every 6 months for the first 2 years. By previous stereotactic localization of the target, RT was delivered with 28 daily fraction of 1.8 Gy by multiple non coplanar arcs dynamically conformed by a micro multileaf-collimator. At diagnosis, in all 5 patients, visual acuity limitations of different degrees were found, while exophthalmos was present in 2, diplopy in 2, orbital pain in 1, and proptosis in 1. In all patients pre-treatment MRI showed an orbital mass involving the optic nerve. After radiotherapy, previous symptoms improved in all patients. However, after RT the MRI consistently showed a stationary status compared to the MRI before RT. At a median follow up of 26 months (range 9–37) all patients had a subjective and/or objective better visual performance than before RT without any evidence of disease progression. No late side effects were recorded. Accordingly to the current literature, our experience confirms the efficacy and the safety of FSRT in patients with orbital ONSM.
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  • Current Concentration of Artificial Radionuclides and Estimated Radiation Doses from 137Cs around the Chernobyl Nuclear Power Plant, the Semipalatinsk Nuclear Testing Site, and in Nagasaki
    Yasuyuki TAIRA, Naomi HAYASHIDA, Gopalganapathi M. BRAHMANANDHAN, Yuji ...
    2011 Volume 52 Issue 1 Pages 88-95
    Published: 2011
    Released on J-STAGE: January 29, 2011
    Advance online publication: December 24, 2010
    DOIhttps://doi.org/10.1269/jrr.10104
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    To evaluate current environmental contamination and contributions from internal and external exposure due to the accident at the Chernobyl Nuclear Power Plant (CNPP) and nuclear tests at the Semipalatinsk Nuclear Testing Site (SNTS), concentrations of artificial radionuclides in edible mushrooms, soils and stones from each area were analyzed by gamma spectrometry. Annual effective doses were calculated for each area from the cesium contamination. Calculated internal effective doses of 137Cs due to ingestion of mushrooms were 1.8 × 10–1 mSv/year (y) in Gomel city (around CNPP), 1.7 × 10–1 mSv/y in Korosten city (around CNPP), 2.8 × 10–4 mSv/y in Semipalatinsk city, and 1.3 × 10–4 mSv/y in Nagasaki. Calculated external effective doses of 137Cs were 3.4 × 10–2 mSv/y in Gomel city, 6.2 × 10–2 mSv/y in Korosten city, 2.0 × 10–4 mSv/y in Semipalatinsk city, and 1.3 × 10–4 mSv/y in Nagasaki. Distribution of radionuclides in stones collected beside Lake Balapan (in SNTS) were 241Am (49.4 ± 1.4 Bq/kg), 137Cs (406.3 ± 1.7 Bq/kg), 58Co (3.2 ± 0.5 Bq/kg), and 60Co (125.9 ± 1.1 and 126.1 ± 1.1 Bq/kg). The present study revealed that dose rates from internal and external exposure around CNPP were not sufficiently low and radiation exposure potency still exists even though current levels are below the public dose limit of 1 mSv/y (ICRP1991). Moreover, parts of the SNTS area may be still contaminated by artificial radionuclides derived from nuclear tests. Long-term follow-up of environmental monitoring around CNPP and SNTS, as well as evaluation of health effects in the population residing around these areas, may contribute to radiation safety with a reduction of unnecessary exposure of residents.
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  • Intrafractional Respiratory Motion for Charged Particle Lung Therapy with Immobilization Assessed by Four-Dimensional Computed Tomography
    Suguru DOBASHI, Toshio SUGANE, Shinichiro MORI, Hiroshi ASAKURA, Naoyo ...
    2011 Volume 52 Issue 1 Pages 96-102
    Published: 2011
    Released on J-STAGE: January 29, 2011
    DOIhttps://doi.org/10.1269/jrr.10019
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    The aim of this study was to quantify the magnitude of intrafractional lung tumor motion under free-breathing conditions with an immobilization device using four-dimensional computed tomography (4DCT). 4DCT data sets were acquired for 17 patients with lung tumors receiving carbon ion beam therapy. A single respiratory cycle was subdivided into 10 phases, and intrafractional tumor motion was calculated by identifying the gross tumor volume (GTV) center of mass (COM) in two scenarios; respiratory-ungated and -gated treatments, which were based on a whole respiratory cycle and a 30% duty cycle around peak exhalation, respectively. For the respiratory-ungated case, the mean (± standard deviation) GTV-COM displacements from the peak exhalation position over the 17 patients were 0.6 (± 0.8) / 0.9 (± 1.2) mm, 2.0 (± 1.4) / 0.4 (± 0.7) mm, and 0.2 (± 0.5) / 7.8 (± 6.9) mm in left/right, anterior/posterior and superior/inferior directions, respectively, while these were reduced for the respiratory-gated case to 0.3 (± 0.4) / 0.4 (± 0.6) mm (left/right), 0.8 (± 0.7) / 0.3 (± 0.5) mm (anterior/posterior), and 0.1 (± 0.2) / 2.8 (± 2.9) mm (superior/inferior). Quantitative analysis of tumor motion with immobilization is valuable not only for particle beam therapy but also for photon beam therapy.
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Technical Report
  • Size, Concentration and Incubation Time Dependence of Gold Nanoparticle Uptake into Pancreas Cancer Cells and its Future Application to X-ray Drug Delivery System
    Jade Dungao TRONO, Kazue MIZUNO, Noritaka YUSA, Takehisa MATSUKAWA, Ka ...
    2011 Volume 52 Issue 1 Pages 103-109
    Published: 2011
    Released on J-STAGE: January 29, 2011
    Advance online publication: December 24, 2010
    DOIhttps://doi.org/10.1269/jrr.10068
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    One of the restrictions in the potential use of gold markers for medical imaging/tracking of harder tumors is its size. We propose to use gold nanoparticles which, due to its small size, can be administered conveniently via intravenous injection. One of the factors that determine the clinical utility of nanoparticles is the ability to enter cells. In this report, the stability of gold nanoparticles mixed with different media was determined by UV-vis spectroscopy. Gold nanoparticle size was confirmed by TEM. Intracellular uptake using different gold nanoparticle sizes, incubation times and concentrations were analyzed using Atomic Absorption Spectrometry (AAS). Temperature dependence uptake was also measured using AAS. The results showed that pancreas cancer cells uptake 20 nm gold nanoparticles preferentially compared to other gold nanoparticle sizes. Efficient accumulation of gold nanoparticles into pancreas cancer cells can be achieved at longer incubation time and higher concentration. The findings of this study will help in the design and optimization of the gold nanoparticle-based agents for therapeutic and diagnostic applications of X-ray Drug Delivery System.
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Meeting Report
Letter to the Editor
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