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Yunhui Jo
Department of Bio-convergence Engineering, Korea University, Seoul, Korea
Geon Oh, Yongha Gi, Heehun Sung, Myonggeun Yoon
Department of Bio-medical Engineering, Korea University,Seoul, Korea
Eun Bin Joo, Suk Lee
Department of Radiation Oncology, College of Medicine, Korea University, Seoul, Korea
INTERNATIONAL JOURNAL OF RADIATION BIOLOGY2020, VOL. 96, NO. 12, 1528–1533
Purpose: This study was aimed to evaluate the utility based on imaging quality of the fast non-local means (FNLM) filter in diagnosing lung nodules in pediatric chest computed tomography (CT).
Methods: We retrospectively reviewed the chest CT reconstructed with both filtered back projection (FBP) and iterative reconstruction (IR) in pediatric patients with metastatic lung nodules. After applying FNLM filter with six h values (0.0001, 0.001, 0.01, 0.1, 1, and 10) to the FBP images, eight sets of images including FBP, IR, and FNLM were analyzed. The image quality of the lung nodules was evaluated objectively for coefficient of variation (COV), contrast to noise ratio (CNR), and point spread function (PSF), and subjectively for noise, sharpness, artifacts, and diagnostic acceptability.
Results: The COV was lowest in IR images and decreased according to increasing h values and highest with FBP images (P < 0.001). The CNR was highest with IR images, increased according to increasing h values and lowest with FBP images (P < 0.001). The PSF was lower only in FNLM filter with h value of 0.0001 or 0.001 than in IR images (P < 0.001). In subjective analysis, only images of FNLM filter with h value of 0.0001 or 0.001 rarely showed unacceptable quality and had comparable results with IR images. There were less artifacts in FNLM images with h value of 0.0001 compared with IR images (p < 0.001).
Conclusion: FNLM filter with h values of 0.0001 allows comparable image quality with less artifacts compared
Jina Shim, Myonggeun Yoon*
Department of Bio-Convergence Engineering, Korea University, Seoul, Republic of Korea
Department of Diagnostic Radiology, Severance Hospital, Seoul, Republic of Korea
Mi-Jung Lee*
Department of Radiology and Research Institute of Radiological Science, Severance Children’s Hospital, Yonsei University, College of Medicine, Seoul, Republic of Korea
Youngjin Lee
Department of Radiological Science, Gachon University, Incheon, Republic of Korea
Physica Medica 81 (2021) 52-89
Purpose: The entrance beam fluence of therapeutic proton scanning beams can be monitored using a gantry-attachable plastic scintillating plate (GAPSP). This study evaluated the clinical application of the GAPSP using amethod that measures intensity modulated proton therapy (IMPT) beams for patient treatment.
Methods: IMPT beams for the treatment of nine patients, at sites that included the spine, head and neck, pelvis, and lung, were measured using the GAPSP, composed of an EJ-212 plastic scintillator and a CMOS camera. All energy layers distinguished by the GAPSP were accumulated to determine the dose distribution of the treatment field. The evaluated fields were compared with reference dose maps verified by quality assurance.
Results: Comparison of dose distributions of evaluation treatment fields with reference dose distributions showed that the 3%/1 mm average gamma passing rate was 96.4%, independent of the treatment site, energy range and field size. When dose distributions were evaluated using the same criteria for each energy layer, the average gamma passing rate was 91.7%.
Conclusions: The GAPSP is a suitable, low-cost method for monitoring pencil beam scanning proton therapy, especially for non-spot scanning or additional collimation. The GAPSP can also estimate the treatment beam by the energy layer, a feature not common to other proton dosimetry tool.
Seonghoon Jeong
Proton Therapy Center, National Cancer Center, Goyang, Republic of Korea
Myonggeun Yoon⁎ , Jaehyeon Seo
Kwangzoo Chung,⁎ , Sung Hwan Ahn , Boram Lee,
Sun Young Moon, Myonggeun Yoon
Department of Bio-Convergence Engineering, Korea University, Seoul, South Korea
Sun-Young Kim, Dongho Shin
Proton Therapy Center, National Cancer Center, Goyang, South Korea
J. Korean Phys. Soc. 78, 1133–1140 (2021).
Jaehyeon Seo, Yunhui Jo, Sunyoung Moon and Myonggeun Yoon∗
Department of Bio-convergence Engineering, Korea University, Seoul 02841, Korea
Sung Hwan Ahn, Boram Lee and Kwangzoo Chung†
Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul 06351, Korea
Background
Tumor-treating fields (TTFields) is an emerging non-invasive cancer-treatment modality using alternating electric fields with low intensities and an intermediate range of frequency. TTFields affects an extensive range of charged and polarizable cellular factors known to be involved in cell division. However, it causes side-effects, such as DNA damage and apoptosis, in healthy cells.
Objective
To investigate whether thymidine can have an effect on the DNA damage and apoptosis, we arrested the cell cycle of human glioblastoma cells (U373) at G1/S phase by using thymidine and then exposed these cells to TTFields.
Methods
Cancer cell lines and normal cell (HaCaT) were arrested by thymidine double block method. Cells were seeded into the gap of between the insulated wires. The exposed in alternative electric fields at 120 kHz, 1.2 V/cm. They were counted the cell numbers and analyzed for cancer malignant such as colony formation, Annexin V/PI staining, γH2AX and RT-PCR.
Results
The colony-forming ability and DNA damage of the control cells without thymidine treatment were significantly decreased, and the expression levels of BRCA1, PCNA, CDC25C, and MAD2 were distinctly increased. Interestingly, however, cells treated with thymidine did not change the colony formation, apoptosis, DNA damage, or gene expression pattern.
Conclusions
These results demonstrated that thymidine can inhibit the TTFields-caused DNA damage and apoptosis, suggesting that combining TTFields and conventional treatments, such as chemotherapy, may enhance prognosis and decrease side effects compared with those of TTFields or conventional treatments alone.
Hyesun Jeong, Sunghoi Hong
School of Biosystems and Biomedical Sciences, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea
Department of Public Health Science, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea
Yunhui Jo, Myonggeun Yoon
Department of Bio- Convergence Engineering, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea
Genes Genom 43, 995–1001 (2021)
Eunae Choi and Myong Geun Yoon
Department of Bio Convergence Engineering, Korea University, Seongbuk-gu, Republic of Korea
Kwon Su Chon
Eunae Choi and Myonggeun Yoon∗
Masao Suzuki and Naruhiro Matsufuji
National Institutes for Quantum and Radiological Science and Technology, Chiba 263-8555, Japan
Wonguyn Jung
Proton Therapy Center, National Cancer Center, Goyang Korea
Myonggeun Yoon∗
Kwangzoo Chung†