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4th International Conference on Electronics, Biomedical Engineering, and Health Informatics, ICEBEHI 2023

作者： Katherine Putra, Alfian Pramudita Kurniawan, Angeline Shane Istiqomah, Dezy Zahrotul Sholihah, Nisa’ul Al-Salehi, Khalid Ali Salem Ain, Khusnul Sapuan, Imam Andarini, Esti Biomedical Engineering Master Program Department of Physics Faculty of Science and Technology Universitas Airlangga Surabaya60115 Indonesia Biomedical Engineering Study program Department of Physics Faculty of Science and Technology Universitas Airlangga Surabaya Indonesia Department of Physics Faculty of Science and Technology Universitas Airlangga Surabaya Indonesia School of Nursing Southern Medical University Guangdong Guangzhou510515 China

ISBN: (纸本)9789819714629

The motor impairments that stroke patients experience as a primary contributor to death and disability also impact their quality of life. Due to its characteristics as complex muscle signals, the Electromyograph (EMG) signal may be one of the markers in rehabilitation and a substitute that may be used to judge the success of rehabilitation. This study aims to analyze the complexity of EMG signals originating from the flexion of the flexor carpi radialis muscle with various weights indicating the rehabilitation state. It is important to monitor the progress of rehabilitation, and it can be done by using complexity analysis. The complexity of the EMG is examined in this work utilizing entropy measurement, namely Approximate Entropy (ApEn), Sample Entropy (SampEn), and Fuzzy Approximate Entropy (fApEn). We concentrated on the flexor carpi radialis muscle using flexion–extension exercises and varying the weight load. This study’s results indicate differences in the complexity of the EMG signal in the flexor carpi radialis when performing flexion–extension movements. Three differences showed a correlation based on the value of ApEN, SampEn, and fApEn. Complexity Analysis using fApEn showed the best correlation at R = 0.9966, which can be used to evaluate the rehabilitation process. The increase in weight was followed by the increase of the fApEn value, indicating that the value can be used to evaluate the rehabilitation process. The use of complexity analysis of EMG signal from flexion movement in flexor carpi radialis with various weights can be used to indicate the progress in the rehabilitation process. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.

关键词： Entropy

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Prediction of the Binding Mechanism of a Selective DNA Methyltransferase 3A Inhibitor by Molecular Simulation

SSRN

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SSRN 2023年

作者： Kudo, Genki Hirao, Takumi Harada, Ryuhei Hirokawa, Takatsugu Shigeta, Yasuteru Yoshino, Ryunosuke Physics Department Graduate School of Pure and Applied Sciences University of Tsukuba 1-1-1 Tennodai Ibaraki Tsukuba305-8571 Japan Master’s Program in Medical Sciences Graduate School of Comprehensive Human Sciences University of Tsukuba Ibaraki Tsukuba305-8575 Japan Division of Biomedical Science Faculty of Medicine University of Tsukuba 1-1-1 Tennodai Ibaraki Tsukuba305-8575 Japan Center for Computational Sciences University of Tsukuba 1-1-1 Tennodai Ibaraki Tsukuba305-8577 Japan Transborder Medical Research Center University of Tsukuba 1-1-1 Tennodai Ibaraki Tsukuba305-8575 Japan Japan

DNA methylation is an epigenetic mechanism that introduces a methyl group at the C5 position of cytosine. This reaction is catalyzed by DNA methyltransferases (DNMTs) and is essential for the regulation of gene transcription. The DNMT1 and DNMT3A or -3B family proteins are known targets for the inhibition of DNA hypermethylation in cancer cells. A selective non-nucleoside DNMT3A inhibitor that mimics S-adenosyl-l-methionine and deoxycytidine has been developed;however, its selectivity mechanism is unclear because the structure of the inhibitor–protein complex has not yet been determined. Therefore, we performed docking and molecular dynamics simulations to predict the structure of the complex formed by the association between DNMT3A and the selective inhibitor. Through our simulations, binding free energy decomposition analysis, structural isoform comparison, and residue scanning revealed that Arg688 of DNMT3A is involved in the interaction with this inhibitor, as seen by its significant contribution to the binding free energy. The presence of Asn1192 at the corresponding residues in DNMT1 results in a loss of affinity for the inhibitor, suggesting that the interactions mediated by Arg688 in DNMT3A are essential for selectivity. Our study findings can be applied in the design of DNMT-selective inhibitors and methylation-specific drug optimization procedures. © 2023, The Authors. All rights reserved.

关键词： Molecular dynamics

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Cold atmospheric plasma-enabled platelet vesicle incorporated iron oxide nano-propellers for thrombolysis

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Materials Today Bio 2023年 23卷 100876页

作者： Jheng, Pei-Ru Chiang, Chia-Che Kang, Jiunn-Horng Fan, Yu-Jui Wu, Kevin C.-W. Chen, Yan-Ting Liang, Jia-Wei Bolouki, Nima Lee, Jyh-Wei Hsieh, Jang-Hsing Chuang, Er-Yuan Graduate Institute of Nanomedicine and Medical Engineering Graduate Institute of Biomedical Materials and Tissue Engineering Institute of Biomedical Optomechatronics International Ph.D. Program in Biomedical Engineering School of Biomedical Engineering College of Biomedical Engineering Professional Master Program in Artificial Intelligence in Medicine College of Medicine Taipei Medical University Taipei11031 Taiwan Department of Physical Medicine and Rehabilitation Taipei Medical University Hospital Taipei Taiwan Institute of Biomedical Engineering & Nanomedicine National Health Research Institute Keyan Road Zhunan Miaoli City350 Taiwan Department of Chemical Engineering National Taiwan University No.1 Sec. 4 Roosevelt Rd Taipei10617 Taiwan Department of Plasma Physics and Technology Faculty of Science Masaryk University Brno Czech Republic Center for Plasma and Thin Film Technologies Ming Chi University of Technology New Taipei City Taiwan Department of Materials Engineering Ming Chi University of Technology New Taipei City Taiwan Cell Physiology and Molecular Image Research Center Taipei Medical University-Wan Fang Hospital Taipei11696 Taiwan

A new approach to treating vascular blockages has been developed to overcome the limitations of current thrombolytic therapies. This approach involves biosafety and multimodal plasma-derived theranostic platelet vesicle incorporating iron oxide constructed nano-propellers platformed technology that possesses fluorescent and magnetic features and manifold thrombus targeting modes. The platform is capable of being guided and visualized remotely to specifically target thrombi, and it can be activated using near-infrared phototherapy along with an actuated magnet for magnetotherapy. In a murine model of thrombus lesion, this proposed multimodal approach showed an approximately 80 % reduction in thrombus residues. Moreover, the new strategy not only improves thrombolysis but also boosts the rate of lysis, making it a promising candidate for time-sensitive thrombolytic therapy. © 2023 The Authors

关键词： Infrared devices

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Estimation of Occupational Eye Lens Dose in Nuclear Medicine: A Monte Carlo Study

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Journal of medical Imaging and Radiation sciences 2022年第4期53卷 S29-S29页

作者： Morhrasi, Pakjira Jumpee, C Charoenphun, P Chuamsaamarkkee, K Master of Science Program in Medical Physics Department of Diagnostic and Therapeutic Radiology Faculty of Medicine Ramathibodi Hospital Mahidol University Bangkok Thailand Division of Nuclear Medicine Department of Diagnostic and Therapeutic Radiology Faculty of Medicine Ramathibodi Hospital Mahidol University Bangkok Thailand Department of Radiologic Technology Faculty of Associated Medical Sciences Chiang Mai University Chiang Mai Thailand

IntroductionThe radiation workers in nuclear medicine are involved with unsealed radioactive source. The measurement of eye lens dose using dosimeter could lead to significant error and uncertainties. Therefore, this study aims to estimate the eye lens dose of the radiation workers in nuclear medicine using Monte Carlo (MC) simulation. MethodsIn this work, MC simulations were performed using MCNP5. The measured Hp(3) using NanoDot TM in cylindrical phantom with 60Co and 137Cs standard sources were conducted to validate MCNP code. Additionally, the simulated air kerma rate constants have been validated using commonly used radionuclides including 18F, 99mTc and 131I. Then, the validated MCNP code was used to estimate the eye lens at distance of 10 to 50 cm from eye level of PIMAL phantom. ResultsThe percentage error of experimental and simulation results were less than the acceptance limit of 10% for code validation. Then, the clinical source geometries were simulated e.g., 3 mL solution in the 5-mL syringe for 18F, 1 mL solution in the 3-mL syringe for 99mTc and the capsule in the 10-mL vial for 131I. The eye lens doses were increased when the energy of emitted photon increased. Subsequently, 18F provided highest eye lens dose followed by 131I and 99mTc. At 10 cm, the eye lens dose rates were 20.55,7.90 and 2.33 μSv/MBq/hr for 18F, 131I and 99mTc respectively. The eye lens dose rates were decreased when the distance increased as expected. At 50 cm, the eye lens dose rates were dramatically dropped to 1.16, 0.46 and 0.14 μSv/MBq/hr for 18F, 131I and 99mTc respectively. ConclusionThe eye lens dose rates from commonly source geometries and distances were simulated in this work. The values could be used as a caution limit to ensure that no individual is committed to unacceptable risk due to radiation exposure.

关键词： eye lens dose occupational exposure Monte Carlo simulation radiation protection

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Validation of image registration accuracy using TG-132 virtual phantoms

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Journal of medical Imaging and Radiation sciences 2022年第4期53卷 S61-S61页

作者： Kamonchanok, Archawametheekul Suphaphong, S Puttanawarut, C Jiarpinitnun, C Stansook, N Khachonkham, S Master of Science Program in Medical Physics Department of Diagnostic and Therapeutic Radiology Faculty of Medicine Ramathibodi Hospital Mahidol University Bangkok Thailand Division of Radiation Oncology Department of Diagnostic and Therapeutic Radiology Faculty of Medicine Ramathibodi Hospital Mahidol University Bangkok Thailand Chakri Naruebodindra Medical Institute Faculty of Medicine Ramathibodi Hospital Mahidol University Nakhorn Pathom Samutprakarn Thailand

IntroductionImage registration is an essential part of radiotherapy workflow which allows the use of multimodality imaging for tumor and normal structures delineation. The result of misregistration can lead to an error in subsequent processes. Therefore, this study aims to validate our currently operated image registration software, Eclipse TPS v.16.1, using the TG-132 virtual phantom. MethodsThe TG-132 virtual phantoms were used to validate rigid registration accuracy using quantitative metrics recommended in the AAPM TG-132 report. Multimodality images of geometric and anatomical datasets were segmented and used to quantify the dice similarity coefficients (DSC) and centre of mass shift (COM). The propagated landmarks on the virtual phantom were calculated as the target registration error (TRE) over six landmarks. The obtained results were compared to the recommendation tolerance. ResultsThe registration metrics showed the register accuracy with a high DSC above the acceptable tolerance (DSC > 0.80). The DSC results of all contours were larger than 0.88 and 0.92 for geometric and anatomical datasets, respectively. The average COM displacement was less than 1 mm for all directions except in rotation for CT to CT images and translation for CT to CBCT images. The average TREs for all datasets were within the acceptable tolerance of 2 mm and 5mm maximum. ConclusionThe rigid registration algorithm provides sufficient accuracy in virtual phantom study analysis with quantitative metrics available in Eclipse TPS. These results corroborated with high conformity values and low displacement errors.

关键词： validation of image registration rigid image registration virtual phantom

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Stopping power ratio databases for proton therapy dose calculation

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Journal of physics: Conference Series 2020年第1期1505卷

作者： N Pischom S Asavaphatiboon P Tangboonduangjit T Liamsuwan Master of Science Program in Medical Physics Department of Diagnostic and Therapeutic Radiology Faculty of Medicine Ramathibodi Hospital Mahidol University Bangkok Thailand Division of Radiotherapy Department of Radiology Surin Hospital Surin Thailand Faculty of Medicine and Public Health HRH Princess Chulabhorn College of Medical Science (PCCMS) Chulabhorn Royal Academy Bangkok Thailand Nuclear Research and Development Division Thailand Institute of Nuclear Technology (Public Organization) Nakhon Nayok Thailand

In modern radiation therapy, ion beams are increasingly used for cancer treatment. Protons are light ions that have Bragg peak characteristic in the depth dose distribution that is optimal for minimizing dose to surrounding normal tissues. In proton therapy treatment planning, the stopping power ratio (SPR) of a given medium to that of water is used for calculating the water-equivalent pathlength (WEPL) of tissues in the patient. Since SPR is related to the computed tomography (CT) number, the conversion from CT numbers to SPRs can be used to find WEPLs of tissue voxels, which are sequentially applied in selecting the initial proton energy. In this work, we investigated the effect of using different CT number to SPR conversion models on proton pencil beam dose calculation. In the SPR calculation, either elemental mean excitation energy (I-value) from the ICRU report or elemental mass stopping power from SRIM software were used. For each approach, four energy dependent scenarios were investigated. The ICRU model and the SRIM model showed a monotonic correlation of SPRs for most tissue types. The 2D dose distribution was calculated by a MATLAB-based proton therapy treatment planning system, PSPLAN. The results suggest that elemental I-values and elemental mass stopping power can be used interchangeably for SPR calculation. Moreover, CT number to SPR conversion models obtained for specific proton energy and average proton energy did not cause difference in pencil beam dose calculation unless the proton energy was relatively low.

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Evaluation of Delta 4 system in patient specific QA for VMAT technique: Retrospective lung VMAT cases

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Journal of physics: Conference Series 2019年第1期1248卷

作者： J Khaophong P Yongvithisatid K Pairat P Dechsupa P Tangboonduangjit S Asavaphatiboon Master of Science Program in Medical Physics Faculty of Medicine Ramathibodi Hospital Mahidol University Bangkok 10400 Thailand Radiosurgery Center Faculty of Medicine Ramathibodi Hospital Mahidol University Bangkok 10400 Thailand

The objective of this study was to evaluate the Delta 4 system for lung VMAT technique. The standard fields and VMAT plans were generated into the homogeneous and heterogeneous phantoms and were evaluated using 2%/2 mm criterion to validate the Delta 4 system. For retrospective study, five lung VMAT plans were evaluated using 2%/2 mm criterion. The point dose was measured to ensure the accuracy of beam delivery. Moreover, the 1.0 mm MLC position error was introduced into the VMAT plan of homogeneous phantom and was evaluated using 2%/2 mm and 1%/1 mm criteria to evaluate the small error detection. The range of percentage gamma passing rate for standard fields and VMAT in both phantoms was 94.6% to 99.8%. For five retrospective lung VMAT plans, the range of percentage gamma passing rate was 96.6% to 99.5%. The point dose differences were within ± 3%. For 1.0 mm MLC position error, the percentage gamma passing rate for 2%/2 mm and 1%/1 mm were 99.1% and 83.6%, respectively. In conclusion, the Delta 4 system can be used in patient specific QA for lung VMAT cases using 2%/2 mm criterion. The error magnitude 1.0 mm can be detected by 1%/1 mm criterion.

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Impact of acquisition time on image quality and visibility of Yttrium-90 Positron Emission Tomography: A phantom study

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Journal of physics: Conference Series 2019年第1期1248卷

作者： T Thareeboonchai N Buranatrivedhaya W Sriwiang P Charoenphun K Chuamsaamarkkee Master of Science Program in Medical Physics Faculty of Medicine Ramathibodi Hospital Mahidol University Bangkok 10400 Thailand Department of Therapeutic and Diagnostic Radiology Faculty of Medicine Ramathibodi Hospital Mahidol University Bangkok 10400 Thailand Thailand Institute of Nuclear Technology (Public Organization) Nakhonnayok 26120 Thailand

90Y has internal pair production which enables the imaging of this isotope with positron emission tomography (PET). The acquisition time is a crucial factor which strongly influence the image quality due to very small decay branch of this isotope. Hence, the aim of this study was to evaluate the impact of acquisition time on image quality and visibility of 90Y PET. A NEMA IEC body phantom with set of fillable spheres were filled with 90Y to generate a hot lesion to background ratio of 8:1. PET image was acquired by Philips Gemini TF PET/CT scanner with acquisition time per bed varied from 15, 30, 60 and 120 minutes. Image quality was assessed by percentage hot contrast (HC), image noise (CV), signal-to-noise (SNR) ratio and visibility (VS). From a result, hot spheres and their edges were more defined as acquisition time increased. Additionally, SNR and visibility were increased with acquisition time and sphere size as expected but percentage hot contrast was decreased. Thus, this can be explained by the growing of noise at shorter acquisition times and smaller spheres. In conclusion, 90Y PET imaging was feasible but the imaging protocol should be carefully considered particularly in small object.

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Optimization of couch angles and number of arcs in non-coplanar VMAT for pituitary adenomas

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Journal of physics: Conference Series 2019年第1期1248卷

作者： N Limpichotikul P Yongvithisatid K Pairat P Dechsupa P Changkaew S Suphaphong N Stansook S savaphatiboon P Tangboonduangjit Master of Science Program in Medical Physics Faculty of Medicine Ramathibodi Hospital Mahidol University Bangkok 10400 Thailand Radiosurgery Center Faculty of Medicine Ramathibodi Hospital Mahidol University Bangkok 10400 Thailand Department of Diagnostic and Therapeutic Radiology Faculty of Medicine Ramathibodi Hospital Mahidol University Bangkok 10400 Thailand

Non-coplanar VMAT spares critical organs with short delivery time while maintaining PTV coverage. Due to the growth patterns of pituitary adenoma, the beam angle selection step was simplified by finding the optimal couch angles and number of arcs. The 2 clinical cases with difference PTV sizes were selected to study the results of dose distribution between coplanar and non-coplanar techniques. Later, couch angles were varied from 30° to 90° and 270° to 330° with a 15° interval. The numbers of arcs were varied from 3 to 4 arcs. Then, the selected protocol was applied to 5 pituitary adenoma patients. It was found that 90° and 270° couch angle showed the highest scores. However, these beams passed directly through the body, so the second couch angles of 75° and 285° were selected instead. For number of arcs optimization, 3-arc plan and 4-arc plan demonstrated a similar score. However, the 3-arc plan illustrated an obviously shorter treatment time. After the selection was proven to the 5 patients, there were 4 patients who passed the criteria, while 1 patient did not pass the hippocampal planning criteria. In conclusion, the suggested couch angles were 75° and 285°. The optimal number of arcs for pituitary adenoma was 3 arcs.

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Monte Carlo MCNP-based simulation and radiation measurement of Yttrium-90 bremsstrahlung produced from radiation shielding apparatus

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Journal of physics: Conference Series 2019年第1期1248卷

作者： C Onnomdee C Jumpee J Channuie P Sinkaew K Chuamsaamarkkee P Charoenphun Master of Science Program in Medical Physics Faculty of Medicine Ramathibodi Hospital Mahidol University Bangkok 10400 Thailand Faculty of Associated Medical Sciences Chiang Mai University Chiang Mai 50200 Thailand Thailand Institute of Nuclear Technology (Public Organization) Nakhonnayok 26120 Thailand Department of Therapeutic and Diagnostic Radiology Faculty of Medicine Ramathibodi Hospital Mahidol University Bangkok 10400 Thailand

Yttrium-90 (90Y) has been widely used in therapeutic nuclear medicine including in the selective internal radiation therapy with 90Y-microsphere. In the procedure 90Y source is protected within the radiation shielding apparatus made of perspex. However, bremsstrahlung radiation may be generated when 90Y interacts with matter. The aim of this study was to evaluate bremsstrahlung radiation produced from radiation shielding apparatus using a scintillation detector and Monte Carlo simulation. The 90Y source in glass vial was placed in the radiation shielding apparatus. Bremsstrahlung measurement and spectrum were performed and recorded using thallium-doped sodium iodide (NaI(Tl)) scintillation detector. Counting time and distance between the detector and apparatus were varied to obtain the optimal condition for bremsstrahlung measurement. Monte Carlo N-Particle (MCNP) 5 was used to simulate bremsstrahlung radiation with the same geometry used in the measurement. For experimental measurement results, the optimal distance and counting time were 10 cm and 120 s, respectively. Although the result of bremsstrahlung spectrum from the detector and simulation exhibited similar trend, markedly greater count rate was observed in simulations than in detector measurements. In conclusion, 90Y bremsstrahlung can be produced from radiation protection apparatus and this can be evaluated by either measurement or simulation.

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