Department of Radiological Technology

Medical Infomatics, Science and Technology

Name Title E-Mail address Research Area
Takao Nakamura, Ph.D. in Engineering Professor nakamura(a)md.okayama-u.ac.jp Medical and Biological Engnieering
Sachiko Goto, RT, Ph.D. Associate Professor goto(a)md.okayama-u.ac.jp Medical Image Engineering
Toshinori Maruyama, PhD Associate Professor rbp(a)md.okayama-u.ac.jp Radiological Images
Katsumi Hanamoto, PhD Assistant Professor hana(a)md.okayama-u.ac.jp Quantum Beam Physics, Materials Science
Toshimasa Kusuhara, PhD. Assistant Professor kusuhara(a)okayama-u.ac.jp Medical and Biological Engineering

Radiological Health Supporting Sciences

Name Title E-Mail address Research Area
Masahiro Kuroda, MD, PhD. Professor kurodamd(a)cc.okayama-u.ac.jp Clinical Radiotherapy, Radiation Oncology, Radiation Biology, Hyperthermia
Takehito Taguchi, MD, PhD. Professor taguchan(a)md.okayama-u.ac.jp Human Macroscopic and Microscopic Anatomy
Yoshihiro Takeda, MD, PhD. Professor ytakeda(a)md.okayama-u.ac.jp Nuclear Medicine, Radiology
Kiyonori Yamaoka, Dr Sci, Med Professor yamaoka(a)md.okayama-u.ac.jp Radiological Health Science, Healthy Longevity Science, Analytical Bioscience
Masataka Oita, Ph.D Associate Professor oita-m(a)cc.okayama-u.ac.jp Radiotherapy Physics, Radiation Biophysics, Radiation Metrology
Koichi Shibuya, RT. PhD. Associate Professor kshibuya(a)md.okayama-u.ac.jp Radiographic Technology, Radiation Control
Yousuke Inai, MS Assistant Professor yousuke(a)md.okayama-u.ac.jp Microcirculation, Radiological Sciences
Takahiro Kataoka, PhD. Assistant Professor kataokat(a)md.okayama-u.ac.jp Radiological Health Science, Oxdative Stress
Ryutaro Matsuura, MHSc Assistant Professor matsuu-r(a)cc.okayama-u.ac.jp Radiological Technology

Medical Infomatics, Science and Technology

Takao Nakamura, Ph.D. in Engineering

Research Projects
Development of a portable impedance measuring device for evaluating the skin barrier function
Suppression of the skin barrier function eases the absorption of various chemical substances which in turn cause allergies. It is very useful to quantitatively evaluate the state of the skin barrier in domains such as dermatology, nursing science and cosmetics development. Therefore the authors developed a portable impedance measuring device for evaluating the skin barrier function. This is a compact, lightweight device that can be operated by one hand. After the head contacts the skin, parameters, such as susceptance, B. and admittance, Y, are measured at 2 frequencies and the calculations are completed in about 3 seconds. The equivalent impedance circuitry, that represents some kinds of keratin-removing skins by tape stripping method, consisted of parallel RC circuits. Using these circuits the precision of this device was confirmed using the errors which were within several percent. The correlation with these parameters and TEWL (transepidermal water loss), and the regression expressions for estimation of TEWL were examined. We found that the corneum barrier index was similar to TEWL.
Two-dimensional estimation of knee joint reflex by pendulum test
It is well-known that the knee joint reflex of the spastic patient is facilitated by increasing -motoneuron excitability and decreasing presynaptic inhibition capability. There are however, few reports quantifying these factors. We tried therefore to use these factors to represent the knee joint reflex two-dimensionally. Ten waveforms of knee-joint motion used in the quantification were reconstructed from the pendulum-test data measured from stroke patients of 1 or 1+ MAS grade in supine position by Kim et al [JBSE, Vol. 6, No. 3]. Indices of the quantification were firing-rate to Hd and the reciprocal of firing-rate to presynaptic inhibition neuron Hie. The normalized values were estimated by an inverse pendulum-test simulator in which both spinal-cord model and spindle model were improved so that the value of each parameter might be determined to only one. According to results of the inverse simulation, plots of (Hd, Hie) in the subjects showed a two dimensional extent and there existed some subjects having pretty different values even if with the same MAS and near equal R-I index.
Biodynamic analysis methods using bioelectrical impedance
We developed a system to measure the frequency characteristics of bioelectrical impedances with high time resolution.
List of 5 publications in the field of expertise
  1. Yoshitake Y, Shirai K, Kusuhara T, Nakamura N, Construction of skin impedance model for evaluation of skin barrier functions in case wet-type electrode. Proc IFMBE 15th Int. Conf Biomed Eng 2013; 825-827
  2. Kusuhara T, Jikuya k, Nakamura T, et al. Detection of Knee-Joint Motions Using Two Linear Accelerometers for Pendulum Test. Elect & Com in Japan 2012; 131-C: 1564-1569
  3. Goda N, Yamamoto Y, Nakamura T, et al. Analysis of Effect for Radiation Exposure to Cultured Cells Using Electrical Cell-Substrate Impedance Sensing (ECIS) Method. Biocybernetics and Biomedical Engineering 2007; 27: 223-232
  4. Kusuhara T, Nakamura T, et al. Parameter Analysis of Impedance Pharyngography (IPG) for Assessment of Swallowing Function, Systems & Computers in Japan 2006; 37: 20-27
  5. Nakamura T, et al. Principle of Biodynamic Analysis Using Human Limb Electrical Impedance and Some Applications. Medical Diagnostic Techniques and Procedures 2000: 388-397
 

Sachiko Goto, RT, Ph.D.

Research Projects
(1)Measurement of Glandular Rate on Mammograms for Estimation of Average Glandular Dose
Mammography is an adaptable method to screen for abnormal remarks in females who do not show subjective symptoms. However, there is a small but significant risk of radiation induced carcinogenesis associated with x-ray examination of mammary tissue. In order to justify examining a seemingly healthy group in screening mammography, it is necessary to appreciate the risk of carcinogenesis that may be associated with the radiation absorbed by the breast and to guarantee an optimization of radiological protection. To do so, it is necessary to control the individual patient exposure dose in screening mammography. Mammography is an adaptable method to screen for abnormal remarks in females who do not show subjective symptoms. However, there is a small but significant risk of radiation induced carcinogenesis associated with x-ray examination of mammary tissue. In order to justify examining a seemingly healthy group in screening mammography, it is necessary to appreciate the risk of carcinogenesis that may be associated with the radiation absorbed by the breast and to guarantee an optimization of radiological protection. To do so, it is necessary to control the individual patient exposure dose in screening mammography.
(2)Myocardial T1 Mapping with Magnetic Resonance Imaging (MRI)
Myocardial T1-mapping recently emerged as a promising method for quantitative non-invasive tissue characterization in numerous cardiomyopathies. The myocardium assessment by T1 mapping with MRI requires a special sequence that selects the facilities based on cost. Then, we propose a general T1-weighted turbo field echo (T1-TFE) sequence with inversion pulse for myocardial T1 mapping.
List of 5 publications in the field of expertise
  1. Katsuhiro Kida, Sachiko Goto, Yoshiharu Azuma. High spatial resolution MRA of renal arteries using contrast behavior between fat and water during transient phase before reaching a steady state. European Journal of Radiology 2012-81-5-846-850.
 

Toshinori Maruyama, PhD

Research Projects
① Study of developing teaching materials that support the acquisition of the radiographic technique to students by using widely-used PC
② Study of the evaluation of medical images, and the improvement of image quality
① A radiographic technique that positions a patient to maximize efficient use of the equipment and minimizes the dosage of X-rays received by the patient is important. A radiology technician should have superior knowledge of human anatomy including the location, shape, and size of examined organs in all positions, from prone to standing. Students studying to be radiology technicians have to learn the most appropriate and efficient technique. It is important to understand the relationship between the positioning of the patient and the incident X-rays. In our study, we are developing teaching materials that support learning radiographic techniques using phantom CT images and the common PC. By using CT images, plane images of the body can be produced such as those shown in Fig.1 and Fig.2. By confirming those images, students can understand the relationship between different X-ray images and the corresponding patient position without actual using X-ray equipment. Developing these teaching materials will help students attain a deep understanding of anatomy and efficiently and accurately acquire radiographic skills. ② We are investigating the image processing method for noise rejection in a medical image and the method of producing a two-dimensional plane image from CT images.
List of 5 publications in the field of expertise
  1. Toshinori Maruyama, Hideki Yamamoto, “Reconstruction of Knee Joint Image from CT Data using Positioning Doll”, 2015 IEEE International Conference on Imaging Systems and Techniques Proceedings , pp.309-314, September, 2015
  2. Toshinori MARUYAMA, Hideki YAMAMOTO,(Maruyama T. , Yamamoto H.)“Positioning Training Tool for Radiography”,Positioning, Vol. 4, No. 4(Published Online November 2013 in Scientific Research Publishing ISSN Online 2150-8520), pp.289-300, November, 2013
 

Katsumi Hanamoto, PhD

Research Projects
Radiation sources from pyroelectric crystals
Pyroelectric crystals have spontaneous polarized charges on the surface. The surface charge is electrically neutral due free compensation charges in ambient air. The amount of spontaneous polarization charges can be varied by changing the temperature, which in turn varies the amount of charge that appears on the crystal surface. For example, negative compensation charges appear on the (001) surface of a LiTaO3 crystal by raising the temperature of the crystal. The compensation charges gradually discharge into the air. In a vacuum, however, the charges accumulate to form a high potential, which then grounds via energetic electrons being ejected from the surface. Brownridge et. al. discovered that when these energetic electrons contact a metal target, characteristic X-rays and bremsstrahlung radiation are produced when using a pyroelectric CsNO3 crystal [1]. Thereafter, mostly monoenergetic electrons [2,3] and positive ions [3] were observed using pyroelectric LiNbO3 and LiTaO3 crystals. Furthermore, neutron production originating from D-D fusion reaction was observed using a pyroelectric LiTaO3 crystal [4]. Hence, this work suggests that pyroelectric crystals have the potential to develop a compact radiation source for electrons, photons, ions, and neutrons without a high voltage power supply. In order to develop a compact radiation source, we investigated a method for controlling radiation sources using the pyroelectric crystals. We investigated the X-ray energy and intensity produced by a LiTaO3 single crystal over a wide range of pressures since there have been no past studies on this [5-7]. We found that the pressure dependence of the endpoint energy may be attributed to the breakdown potential between the crystal surface and the metal target. We are now studying the effects of the size of the gap between the crystal surface and the metal target on X-ray energy and intensity. [1] J.D. Brownridge, Nature 358 (1992) 287. [2] J.D. Brownridge, S.M. Shafroth, D.W. Trott, B.R. Stoner, W.M. Hooke, Appl. Phys. Lett. 78 (2001) 1158. [3] J.A. Geuther, Y. Danon, J. Appl. Phys. 97 (2005) 074109. [4] B. Naranjo, J.K. Gimzewski, S. Putterman, Nature 434 (2005) 1115. [5] K. Hanamoto, A. Kawabe, A. Sakoda, T. Kataoka, M. Okada, K. Yamaoka, Nucl. Instr. Meth. A 669 (2012) 66. [6] K. Hanamoto, T. Kataoka, K. Yamaoka, Appl. Radat. Isot. 116 (2017) 134. [7] K. Hanamoto, T. Kataoka, K. Yamaoka, Appl. Radat. Isot. 135 (2018) 40.
List of 5 publications in the field of expertise
  1. Hanamoto K, Kataoka T, Yamaoka K, Pressure dependence of X-rays produced by an LiTaO3 single crystal over a wide range of pressure. Appl Radiat Isot 2018;135:40-42
  2. Hanamoto K, Kataoka T, Yamaoka K, Pressure dependence of X-rays produced by an LiTaO3 single crystal at the pressures of 1-20 Pa. Appl Radiat Isot 2016;116:134-137
  3. Hanamoto K, Kawabe A, Sakoda, A, Kataoka T, Okada M, Yamaoka K, Pressure dependence of X-rays produced by an LiTaO3 single crystal at low pressures. Nucl Instr Meth A 2012;669:66-69
  4. Hanamoto K, Yamaoka K, Simplification of analysis for comparison of radioactive characteristics and its application to some minerals for radon therapy. Int Congress Series 2005; 1276:253-255
  5. Hanamoto K, Yamaoka K, A comparative study on radioactive characteristics of the minerals for radon therapy. Radiat Measurements 2005; 39:157-160
 

Toshimasa Kusuhara, PhD.

Research Projects
1. Quantitative Classification of Spasticity by Pendulum-test
Spasticity caused by the aging or the cerebrovascular disorders is a disease that significantly interferes with daily motions. Spasticity is classified in clinical practice using Modified Ashworth Scale (MAS). But these results are macroscopic and depends on the examiner's subjectivity. In this study, we are implementing the pendulum-test of the lower legs to detect the spasticity of the quadriceps femoris. Furthermore, we are developing an inverse simulator of the biological model based on the spasticity mechanism and estimating the evaluated value by using pendulum waveforms.
2. Development of the Evaluating Device of Skin Barrier Function by Skin Electrical Impedance
The stratum corneum is the outermost layer of the human body and functions to protect the body from physical invasion or loss of moisture. Decreasing this barrier function causes dry skin or allergic reaction. Understanding the condition of the stratum corneum is important in dermatology. However there is no established method which can be easily implemented. In this study, we develop a device that quantitatively evaluates the skin barrier function of the stratum corneum by utilizing skin electrical impedance.
3. Evaluation of Swallowing Function using Neck Electrical Impedance
Dysphagia caused by esophageal cancer, nerve or muscle disease, etc. greatly decreases QOL (Quality of Life), and is a big problem in aging society. However, there is no quantitative indicator of the swallowing function, and evaluating the swallowing function depends on the doctor's subjectivity using video fluorography (VF) or ultrasound (US) in clinical practice. In this study, we propose an Impedance Pharyngography (IPG) method to measure neck electrical impedance during swallowing. Furthermore, we are working on the quantitative evaluation of dynamic abnormalities of related organs by analyzing IPG waveforms.
List of 5 publications in the field of expertise
  1. Kusuhara T, Jikuya K, Nakamura T, Michinishi H, Yamamoto Y, Okamoto T, Detection of knee-joint motions using two linear accelerometers for pendulum test. Electronics and Communications in Japan 2012; 95, 7: 41-48
  2. Yamamoto Y, Jikuya K, Kusuhara T, Nakamura T, Michinishi H, Okamoto T, Precise Measurement System for Knee Joint Motion During the Pendulum Test Using Two Linear Accelerometers. Advanced Topics in Measurements (InTech) 2012: 19-42
  3. Kusuhara T, Nakamura T, Yamamoto Y, Evaluation of Swallowing Functions Depend on Aging and Surgical Operation of Gullet Cancer Using Neck Bioelectrical Impedance. IFMBE Proceedings vol.14 World Congress on Medical Physics and Biomedical Engineering 2006; 4137: 2609-2612
  4. Kusuhara T, Nakamura T, Yamamoto Y, et al. Parameter Analysis of Impedance Pharyngography (IPG) for Assessment of Swallowing Function. Systems & Computers in Japan 2006; 37, 13: 20-27
  5. Kusuhara T, Nakamura T, YamamotoY, et al. Impedance Pharyngography to Assess Swallowing Function. The Journal of International Medical Research 2004; 32: 608-616
 

Radiological Health Supporting Sciences

Masahiro Kuroda, MD, PhD.

Research Projects
1) Research on breast cancer radiotherapy
The effect of modern clinical radiotherapy techniques for breast cancer are investigated regarding the long-term survival and high quality of life for patients.
2) Research on magnetic resonance imaging (MRI)
Several new sequences for clinical 3-tesla MRI are examined as a superior tumor imaging technique using cell-biology.
List of 5 publications in the field of expertise
  1. Kuroda M. Clinical Practice guide for radiotherapy technique: Breast cancer. Bunkodo 2014; 899-903 (in Japanese)
  2. Hara M, Kuroda M, et al. A new phantom and empirical formula for apparent diffusion coefficient measurement by a 3 Tesla magnetic resonance imaging scanner. Oncol Lett 2014; 8: 819-824
  3. Kuroda M, et al. Hyperthermic Oncology from Bench to Bedside: Development of Heating Device. Springer Science 2014; 421-437
  4. Matsuya, R, Kuroda M, et al. A new phantom using polyethylene glycol as an apparent diffusion coefficient standard for MR imaging. Int J Oncol 2009; 35: 893-900
  5. Kuroda M, et al. Induction thermochemotherapy increases therapeutic gain factor for the fractionated radiotherapy given to a mouse fibrosarcoma. Int J Radiat Oncol Biol Phys 1997; 38: 411-417
 

Takehito Taguchi, MD, PhD.

Research Projects
Cell and tissue morphology by conventional transmission and scanning electron microscopy (TEM, SEM).
1.Cytoskeleton of red blood cell(erythrocyte)
The mammalian erythrocytes transform from a sphere into a biconcave disc followed by enucleation. The biconcave disc shape is considered to be maintained with only a membrane underlain by a membranous cytoskeleton. Our improved hemolysis method can remove abundant hemoglobin from inside the cells and keep the cytoskeleton within the cells to suggest the existence of the cytoplasmic cytoskeleton apart from the classical membranous one by electron microscopy. Subsequent steps are to identify cytoskeleton molecules by immune electron microscopy and further observe the structural dynamics of the skeleton in the erythrocyte enucleation by electron microscopy.
2.Cytoskeleton of bacteria.
The bacterial cytoskeleton has been observed by immune staining/fluorescence microscopy. Our improved hemolysis/TEM has also revealed the microarchitecture of bacterial cytoskeleton. Subsequent steps are to identify cytoskeleton molecules by immune electron microscopy.
3.Collagenous skeletons of various tissues and organs.
The cell NaOH maceration method can digest cell and tissue elements except for some types of collagen fibers in a cold NaOH solution, leading to the observation of tissue collagen skeleton by SEM.
4.Architecture of blood vessels.
The blood vessel corrosion cast method injects resin into the blood vessel lumen and eliminate cell and tissue elements in a hot NaOH solution to observe the microarchitecture of blood vessels in various tissues and organs using SEM
List of 5 publications in the field of expertise
  1. Terasawa K, Taguchi T, et al.. Human erythrocytes possess a cytoplasmic endoskeleton containing beta-actin and neurofilament protein. Arch Histol Cytol. 2006;69:329-340.
  2. Ohtani O1, Ushiki T, Taguchi T, Kikuta A. Collagen fibrillar networks as skeletal frameworks: a demonstration by cell-maceration/ scanning electron microscope method. Arch Histol Cytol. 1988;51:249-61.
  3. Taguchi T. Blood vascular organization of the rat carotid body: a scanning electron microscopic study of corrosion casts. Arch Histol Jpn. 1986;49:243-54.>
 

Yoshihiro Takeda , MD, PhD.

Research Projects
1.Study on evaluating multidrug resistance (MDL) of anticancer drugs by nuclear medicine.
Contents: Elucidation of Tc-99m-MIBI uptake / wash out into multidrug resistant cells and elucidation of multidrug resistance mechanism of anticancer drugs.
2.Evaluation of tumor viability by tumor scintigraphy.
Contents: Use Tc - 99m - MIBI to quantitatively determine the accumulation of tumors and evaluate therapeutic effects and recurrence.
List of 5 publications in the field of expertise
  1. Yatake H, Takeda Y, et al. Accuracy assessment methods of tissue marker clip placement after 11-gauge vacuum-assisted stereotactic breast biopsy: comparison of measurements using direct and conventional methods. Breast Cancer 2017;24(4):593-600
  2. Gotanda T, Takeda Y, et al. Effective energy measurement using radiochromic film: application of a mobile scanner. Polish Journal of Medical Physics and Engineering 2016;22(4):85-92
  3. Hayashida K, Takeda Y, et al. Relationship between Bone Mineral Density and Body Composition Estimated by Dual-Energy X-ray Absorptiometry:Comparison between Groups Aged 20–39 and 40–59 Years. Kobe Journal of Medical Sciences 2015;61(4):101-105
  4. Gotanda T, Takeda Y, et al. Evaluation of GAFCHROMIC EBT2 dosimetry for the low dose range using a flat-bed scanner with the reflection mode. Australasian Physical and Engineering Sciences in Medicine 2013;36(1):59-63
  5. Yatake H, Takeda Y, et al. Improved detection of gastric cancer during screening by additional radiographs as judged necessary by the radiographer. Japanese Journal of Radiology 2011;29:177-186
 

Kiyonori Yamaoka, Dr Sci, Med

Research Projects
1. Study on Health Effects and Medical Applications by Low Dose Radiation:
Especially the activation of biological defense functions, such as antioxidant function by low dose radiation, and the possibility of application to prevention and treatment of lifestyle-related diseases mostly derived from active oxygen. One study involves elucidating the mechanism of radon hot spring indication, and promotion of full-scale research in globally renowned research institutes, medical facilities and universities.
2. Study on Analysis of Environmental Stress Biological Response and Realization of Healthy Longevity:
We are developing and applying a comprehensive system regarding the influence to health on the living body by various human environmental stress factors and evaluating a method to analyse the response of the living body. In addition, we are focusing on realizing healthy longevity by reproducing appropriate amounts of environmental stress, and conducting quantitative research and recommendations based on optimal medical indices.
3. Study on Change Analysis of Environmental Radioactivity and Rationalization of Radiation Protection:
We have made many achievements in analyzing the dynamics of environmental radioactivity at nuclear facilities and researching improved safety on separation management, treatment and disposal of radioactive waste. Currently, through research on health and the social impact of low-dose radiation accompanying the TEPCO Fukushima Daiichi Nuclear Power Plant accident, we are examining a more reasonable radiation protection system.
4. Public Understanding Promotion through Research Activities on Health Effects of Low Dose Radiation:
By analyzing the public survey on the effects of low dose radiation on health, we can discern the information desired by the public, such as comparison of health risks between radiation and other living environmental factors, and construct easy to understand information dissemination methods. In addition, we have comprehensively collated the results from our own research into the health effects of the familiar radon hot springs and the activities of academic surveys both in Japan and abroad. Consequently, we strongly promote disseminating relevant information to the public through writing, lectures and mass communication activities, etc. (The Commendation for Science and Technology by the Minister of Education, Culture, Sports, Science and Technology (Prizes for Science and Technology) in 2016)
List of 5 publications in the field of expertise
  1. Yamaoka K. Activation of antioxidant system by low dose radiation and its applicable possibility for treatment of reactive oxygen species related diseases. J Clin Biochem Nutr 2006;39:114 -133 (Lipid Peroxide and Free Radical Research Award in 2005)
  2. Yamaoka K. Beneficial health effects of low-dose radiation and possibility of its medical applications. Trends in the Sciences (Science Council of Japan) 2011;16(11):75-79
  3. Toyota T, Yamaoka K, et al. Inhibitory effects of pretreatment with radon on acute alcohol-induced hepatopathy in mice. Mediators of Inflammation 2012, Article ID 382801, 10 pages (Doctoral thesis)
  4. Nishiyama Y, Yamaoka K, et al. Suppression of dextran sulfate sodium-induced colitis in mice by radon inhalation. Mediators of Inflammation 2012, Article ID 239617, 11 pages (Doctoral thesis)
  5. Kataoka T, Yamaoka K, et al. Activation of antioxidative functions by radon inhalation enhances the mitigation effects of pregabalin on chronic constriction injury-induced neuropathic pain in mice. Oxidative Medicine and Cellular Longevity 2016, Article ID 9853692, 8 pages
 

Masataka Oita, Ph.D

Research Projects
Recent years, to advance significant clinical technology advances, such as image-guided radiotherapy, intensity-modulated radiotherapy, stereotactic radiotherapy, proton therapy, boron neutron capture therapy enable to deliver selectively higher dose to the tumor with significantly lower doses to normal surrounding tissues. Our laboratory work is both basic and clinical research of radiotherapeutic technology with combination of radiological physics and biology. Our main research projects are described below. (1) Basic research of a computer simulation for 4-Dimensional photon/electron and proton/neutron radiotherapy (2) Clinical research for 4-Dimensional radiotherapy using IGRT related equipment (3) Development and application of radiation detectors using films and other materials for clinical radiological technology (4) Development and application of biological effects for clinical radiological treatment planning (5) Research of radiation control in radiotherapy facilities using a monte carlo simulation
List of 5 publications in the field of expertise
  1. Sasaki M, Tominaga M, Kamomae T, Ikushima H, Kitaoka M, Bando R, Sakuragawa K, M Oita, Influence of multi-leaf collimator leaf transmission on head and neck intensity-modulated radiation therapy and volumetric-modulated arc therapy planning. JJR 2017;35:511-525
  2. Kamomae T, Oita M, Hayashi N, et al. Characterization of stochastic noise and post-irradiation density growth for reflective-type radiochromic film in therapeutic photon beam dosimetry. Phys Med 2016;16:30224-1
  3. Oita M, Nakata K, Sasaki M, et al. Does the biophysical modelling for immunological aspects in radiotherapy precisely predict tumor and normal tissue responses? Med Phys 2016;43:3621
  4. Sasaki M, Ikushima H, Tominaga M, Kamomae, Kishi T, Oita M, et al. Dose impact of rectal gas on prostatic IMRT and VMAT. JJR 2015;33:723-733
  5. Oita M, Uto Y, Tominaga M, et al. Radiosensitivity Unceartainty Evaluation for the In Vitro Biophysical Modeling of EMT6 Cells. Anticancer Res 2014;34:4621-4626
 

Yousuke Inai, MS

Research Projects
Visualization of coronary arterial microvessels in hypertension.
In coronary microcirculation, arterial vascular tone was modulated by the vasodilatory factors, such as nitric oxide (NO) or endothelium-derived hyperpolarizing factor (EDHF). We visualized coronary arterial microvessels in in vivo beating rat hearts by our needle-prove intravital video microscope system to evaluate functional alterations of NO and EDHF time-sequentially in hypertension.
List of 5 publications in the field of expertise
  1. Inai Y, et al. Nitric Oxide-mediated Endothelial Dysfunction is Compensated by EDHF in Spontaneously HypertensiveRats. Supp Circ 2015;110:178-181
  2. Kajiya F, Inai Y, et al. Coronary microcirculation in the beating heart. Med Biol Eng Computing 2013;46:411-419
  3. Kajiya M, Inai Y, et al. Impaired Coronary Capillary Hemodynamics and Irregular Inner Wall in Right Ventricle of Pulmonary Hypertensive Rats. Supp Circ 2012;Ⅲ78
  4. Inai Y, et al. Visualization of Coronary Microcirculation in Rats and Analysis of Size-dependent Flow Control. IEIMBE 27: 9-12
  5. Kajiya M, Inai Y, et al. Impaired NO-mediated vasodilation with increased superoxide but robust EDHF function in right ventricular arterial microvessels of pulmonary hypertensive rats. Am J Physiol Heart and Circulatory Physiology 2008;292:H2737-H2744
 

Takahiro Kataoka, PhD.

Research Projects
Oxidative stress induced by reactive oxygen species (ROS) can cause cell damage and death and can induce many types of disease. Low-dose X-ray or γ- irradiation induces various stimulating effects, especially activation of the biological defense system including antioxidative and immune functions due to the production of a small amount of ROS induced by radiation. Therefore, we examine the positive effects of low-dose irradiation on ROS-related diseases. For example, X-irradiation (0.5 Gy) before or after carbon tetrachloride (CCl4) treatment inhibits hepatopathy in mice. X-irradiation (0.5 Gy) before ischemia-reperfusion injury or cold-induced brain injury also inhibits edema. These findings suggest that low-dose X-ray irradiation has antioxidative effects due to blocking free radical-induced damage or ROS. Moreover, radon inhalation increases superoxide dismutase activity in many organs and inhibits CCl4-induced hepatic and renal damage, streptozotocin-induced type I diabetes, and transient global cerebral ischemic injury. These findings suggest that radon inhalation also has antioxidative effects similar to X-ray or γ- irradiation. This activation contributed to the increase of manganese-superoxide dismutase via nuclear factor-κB activation which occurs in response to DNA damage and oxidative stress. This antioxidative effect against CCl4-induced hepatopathy is comparable to treatment with ascorbic acid (vitamin C) at a dose of 500 mg/kg weight or α-tocopherol (vitamin E) treatment at a dose of 300 mg/kg weight and is due to activation of antioxidative functions. In addition, radon inhalation inhibits carrageenan-induced inflammatory paw edema, suggesting that radon inhalation has anti-inflammatory effects. Furthermore, radon inhalation inhibits formalin-induced inflammatory pain and chronic constriction injury-induced neuropathic pain, suggesting that radon inhalation relieves pain. Interestingly, the therapeutic effects of radon inhalation or the combined effects of radon and pregabalin (3 mg/kg weight) were almost equivalent to treatment with pregabalin at a dose of 1.4 mg/kg weight or 4.1 mg/kg weight, respectively. These findings suggest that the activation of antioxidative functions by radon inhalation enhances the mitigation effects of pregabalin on chronic constriction injury-induced neuropathic pain in mice. Thus, low-dose irradiation very likely activates the defense systems in the body, and therefore, contributes to preventing or reducing ROS-related injuries, which are thought to involve peroxidation.
List of 5 publications in the field of expertise
  1. Kataoka T. Study of Antioxidative Effects and Anti-inflammatory Effects in Mice due to Low-dose X-irradiation or Radon Inhalation. J Radiat Res 2013;54:587-596
  2. Kataoka T, Yamaoka K, et al. Activation of antioxidative functions by radon inhalation enhances the mitigation effects of pregabalin on chronic constriction injury-induced neuropathic pain in mice. Oxid Med Cell Longev 2016;2016; 8 pages (Article ID 9853692)
  3. Kataoka T, Yamaoka K, et al. Radon inhalation protects against transient global cerebral ischemic injury in gerbils. Inflammation 2014;37:1675-1682
  4. Kataoka T, Yamaoka K, et al. Protective effects of radon inhalation on carrageenan-induced inflammatory paw edema in mice. Inflammation 2012;35:713-722
  5. Kataoka T, Yamaoka K, et al. Study of the response of superoxide dismutase in mouse organs to radon using a new large-scale facility for exposing small animals to radon. J Radiat Res 2011;52:775-781
 

Ryutaro Matsuura, MHSc

Research Projects
1.Study on image quality of radiation diagnostic images
Image quality analysis is related to X-ray imaging, X-ray CT and MRI. We research indices including resolution and noise when evaluating image quality. We also study the effect of imaging method and filtering on image quality.
2.New MRI imaging method
We study clinical research on new imaging methods used in MRI. Compared with conventional methods, we find reduced imaging time, improved image quality, and adaptation to specific diseases.
3.Analysis of substances using dual-energy CT
There is a technique that utilizes two X-rays with different energies to create an image by utilizing the different absorption characteristics for each energy. The atomic number, density, moisture content etc. of a target can be obtained by utilizing this technique. We aim to use this technique to accurately measure the type of calculus, bone density and water content of objects.
4.Skill training before clinical training and survey of students' attitudes
Study and observation of students' awareness of clinical change will vary after taking the Objective Structured Clinical Examination (OSCE). At the same time, we using Information and Communication Technology (ICT) to improve the efficiency of training.
List of 5 publications in the field of expertise
  1. 1Takao Hiraki, Tetsushi Kamegawa, Takayuki Matsuno, Jun Sakurai, Yasuzo Kirita, Ryutaro Matsuura, et al. Robotically Driven CT-guided Needle Insertion: Preliminary Results in Phantom and Animal Experiments. Radiology 2017:285 (2):454-461