Synthesis of the orhto, meta, and para isomers of cycloaliphatic epoxy for cationic ring opening polymerization on UV curing

이도완,노승만 한국공업화학회 2022 한국공업화학회 연구논문 초록집 Vol.2022 No.1

생체 외 조직 고 분해능 Magic Angle Spinning을 이용한 정상 Adult Mice에서의 뇌 부위별 뇌 신경화학 대사물질 정량분석

이도완,우동철,이성호,김상영,김구영,임향숙,최치봉,김휘율,이창욱,최보영,Lee, Do-Wan,Woo, Dong-Cheol,Lee, Sung-Ho,Kim, Sang-Young,Kim, Goo-Young,Rhim, Hyang-Shuk,Choi, Chi-Bong,Kim, Hwi-Yool,Lee, Chang-Wook,Choe, Bo-Young 한국의학물리학회 2010 의학물리 Vol.21 No.1

본 연구는 생체 외 $^1H$ 고분해능 매직앵글스핀닝($^1H$ High-Resolution Magic Angle Spinning; $^1H$ HR MAS) 기술을 이용하여 정상군 adult mice의 뇌에서의 부위별 뇌 신경화학 대사물질(brain neurochemical metabolites)을 정량적으로 분석하고, 이를 이용하여 정상군의 뇌 대사물질의 표준 data base를 정립하기 위함이다. 실험에 사용된 adult mice는 C57BL/6J 모델의 체중 25~28 g, 40주령 수컷 10마리를 사용하였으며, 연령과 성별을 일치시켰다. 또한 뇌의 전두엽(frontal cortex), 측두엽(temporal cortex), 해마(hippocampus), 시상(thalamus) 총 4개의 부위를 채취하여 생체 외 $^1H$ 고분해능 매직앵글 스핀닝 실험을 진행 하였다. 생체 조직의 뇌 대사물질의 절대농도를 획득하기 위하여 대표적인 대사물질(Ace, NAA, NAAG, tCr, Cr, tCho, Cho, mIns, GPC+PC, Lac, GABA, Glu, Gln, tau, Ala)을 각 피크의 면적과 대사물질의 프로톤 개수를 계산하였다. 결과적으로 정상 군에서의 mice 뇌의 신경화학 대사물질들을 Acet, NAA, NAAG, Cho, mIns가 부위별로 절대농도차의 유의성을 나타내었으며, 이 외의 대사물질에서는 유의성이 없는 것으로 나타났다. 본 연구 결과를 토대로 $^1H$ HR-MAS을 이용한 생체조직 실험은 뇌조직 내 대사물질의 절대농도를 측정하고 기본적인 지표를 확보하는데 매우 정확하고 정량적인 방법이 될 수 있을 것으로 사료되며, 더 나아가 mice를 이용한 인간질병 모델의 실험동물에서의 뇌 신경화학 대사물질의 표준 자료화 하는데 도움이 될 수 있을 것으로 판단된다. The purpose of this study is to quantitate regional neurochemical profile of regional normal adult mice brain and assess regional metabolic differences by using ex vivo $^1H$ high-resolution magic angle spinning nuclear magnetic resonance spectroscopy ($^1H$ HR-MAS NMRS). The animals were matched in sex and age. The collected brain tissue included frontal cortex, temporal cortex, thalamus, and hippocampus. Quantitative 1D spectra were acquired on 40 samples with the CPMG pulse sequence (8 kHz spectral window, TR/TE = 5500/2.2 ms, NEX = 128, scan time: 17 min 20 sec). The mass of brain tissue and $D_2O$+TSP solvent were 8~14 mg and 7~13 mg. A total of 16 metabolites were quantified as follow: Acet, NAA, NAAG, tCr, Cr, tCho, Cho, GPC + PC, mIns, Lac, GABA, Glu, Gln, Tau and Ala. As a results, Acet, Cho, NAA, NAAG and mIns were showed significantly different aspects on frontal cortex, hippocampus, temporal cortex and thalamus respectively. The present study demonstrated that absolute metabolite concentrations were significantly different among four brain regions of adult mice. Our finding might be helpful to investigate brain metabolism of neuro-disease in animal model.

Investigation of the Neuroprotective Effects of Bee-venom Acupuncture in a Mouse Model of Parkinson’s Disease by Using Immunohistochemistry and <i>In−vivo</i> ¹H Magnetic Resonance Spectroscopy at 9.4 T

윤문현,이도완,김현진,정진영,두아름,박히준,김승남,최보영 한국물리학회 2013 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.62 No.2

Neuroprotective therapeutics slows down the degeneration process in animal models of Parkinson’s disease (PD). The neuronal survival in PD animal models is often measured by using immunohistochemistry. However, dynamic changes in the pathology of the brain cannot be explored with this technique. Application of <i>in-vivo</i> ¹H magnetic resonance spectroscopy (¹H MRS) can cover this shortcoming, as these techniques are non-invasive and can be repeated over time in the same animal. Thus, the sensitivity of both techniques to measure changes in the PD pathology was explored in an experiment studying the neuroprotective effects of the vigilance enhancer bee-venom (BV) in a mouse model of PD. The mice were pre-treated with 0.02-ml BV administered to the acupuncture point GB34 (Yangneungcheon) once every 3 days for 2 weeks. Three groups were classified as control, MPTP-intoxicated PD model and BV-treated mice. Outer volume suppression combined with the ultra-short echo-time STEAM (TE = 2.2 ms, TM = 20 ms, TR = 5000 ms) was used for localized <i>in-vivo</i> ¹H MRS. Based on the ¹H MRS spectral analysis, substantial changes of the neurochemical profiles were evaluated in the three investigated groups. In particular, the glutamate complex (Glx)/creatine (Cr) ratio (7.72 ± 1.25) in the PD group was significantly increased compared to that in the control group (3.93 ± 2.21, P = 0.001). Compared to the baseline values, the Glx/Cr ratio of the BV-treated group was significantly decreased 2 weeks after MPTP intoxication (one-way ANOVA, p < 0.05). In conclusion, the present study demonstrated that neurochemical alterations occurred in the three groups and that the neuroprotective effects of the BV acupuncture in a mouse model of PD could be quantified by using immunohistochemistry and ¹H MRS.

Quality Assurance for Diffusion Tensor Imaging Using an ACR Phantom: Comparative Analysis with 6, 15, and 32 Directions at 1.5T and 3.0T MRI Systems

이정훈,김상영,이도완,정진영,Kyu-Ho Song,최보영 한국물리학회 2014 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.65 No.1

Although diffusion tensor imaging (DTI) has been widely used for the quantitative analyses ofthe integrity of white matter in the brain in clinical and research fields, quality assurance (QA) forDTI has not been fully established. Thus, we suggest a QA guideline for DTI using the AmericanCollege of Radiology (ACR) Magnetic resonance imaging (MRI) head phantom. In this study, thegeometric accuracy, slice-position accuracy, image intensity uniformity, percent signalghosting, lowcontrastobject detectability, image distortion, fractional anisotropy (FA), and apparent diffusioncoefficient (ADC) were measured and evaluated in 1.5T and 3.0T MRI scanners equipped withan 8-channel SENSE head coil. The standard axial spin echo (SE) T1-weighted MR images andDTI with 6, 15 and 32 directions were obtained. Concerning geometric accuracy, image twisting inthe three directions was observed due to the inhomogeneity of echo planar imaging (EPI). Imageintensity uniformity was significantly lower for DTI than for the standard SE T1-weighted MRimages. Percent signal ghosting was higher for images from 3.0T MRI than for images from 1.5TMRI. Low-contrast object detectability was visually identified and measured at a low contrasttonoiseratio (CNR) and a low signaltonoise ratio (SNR). Image distortion changed remarkably to the phaseencodingdirection. The present study using the ACR MRI phantom suggests a QA method forDTI with high reproducibility and easy accessibility.

Evaluation of Fractional Anisotropy and Apparent Diffusion Coefficient of Broca’s Area in Patients with Parkinson’s Disease: Quantitative MR Diffusion Tensor Imaging Study at 3 Tesla

이정훈,최보영,이경배,김상영,이도완,최연봉 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.58 No.2

Parkinson’s disease (PD) is a neurodegenerative disorder caused by progressive loss of dopaminergic neurons in the substantia nigra. The symptoms of Parkinson’s disease include movement, speech and sleep disorders, as well as depression. With regard to the speech disorders, 9 out of 10 patients have difficulties with communication. To date, the neurological mechanisms associated with the speech disorders of PD have not been identified. The purpose of this study was to determine if changes in the fractional anisotropy (FA) and in the apparent diffusion coefficient (ADC) of Broca’s and Wernicke’s areas could be observed in patients with PD by diffusion tensor imaging (DTI). Patients over 60 years of age were divided into a gender- and aged-matched control group of 11 and gender- and aged-matched Parkinson group of 11; the experiments were performed in these two groups. For comparison of the two groups, a single-shot spin-echo EPI sequence for the DTI and 3D T1 turbo field echo sequences for anatomical information were obtained. The acquired images were used to reconstruct the fiber bundles connected to the arcuate fasciculus (AF) in Broca’s and Wernicke’s areas by fiber tractography. The regions of interest (ROIs) were selected from the nerve fibers in both areas. Values of the FA and ADC were obtained. The mean FA values in Broca’s and Wernicke’s areas were lower in the PD group than in the control group; this difference was statistically significant (p < 0.001, p = 0.045). However, the ADC values in the PD group were higher in both areas compared to the control group; this difference was not statistically significant (p = 0.115, p = 0.224). The two major findings of this study were that the FA values in patients with PD were significantly lower in Broca’s and Wernicke’s areas compared to the controls and, the pathways associated with nerve fibers in Broca’s and Wernicke’s areas in patients with PD could be visualized by fiber tractography. The results of this study suggest that neurodegenerative changes in the brains of patients with PD can be observed in specific language areas of the cortex.

Evaluations of ACR MRI Phantom Images with SENSE Factors by Using the JPEG2000 Image Compression Technique

이경배,이정훈,김상영,이도완,최보영,최연봉,성동욱,박용성,홍성완 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.58 No.5

Until now, in the Magnetic resonance imaging image quality assessment using JPEG2000 software, phantom images have been mostly assessed by the compression rate, not considering SENSE factors. In this study, performed on a Philips 3.0-Tesla scanner, we took images for various SENSE factors (1, 1.5, 2, 2.5, and 3) and used the ACR MRI phantom system, largely used worldwide. We performed lossy compression of the individual images by using the JPEG2000 software to evaluate those images (Q-factor = 5:1, 10:1, 20:1, and 40:1, respectively). According to the ACR MRI QC manual, the geometric accuracy of the phantom images did not depend on the SENSE factors and on the lossy image compression rate. Without any change induced by the SENSE factors and on the lossy image compression rate, the high contrast spatial resolution measured 1.0 mm in T1 TSE. The slice thickness accuracy was measured at 4.36 mm, 4.36 mm, and 4.32 mm in the original, 5:1 and 10:1 compressions of the T1 TSE, respectively, without any change in the SENSE factors. However, in the 20:1 lossy compression, it was reported at 4.28 mm, thus surpassing the baseline. In the compressions of the T2 TSE, it measured on average 4.54 mm, 4.54 mm, 4.53 mm, and 4.46 mm in the original, 5:1, 10:1, and 20:1 compressions, respectively, without any change in the SENSE factors. The slice position accuracy in slice 1 and slice 11 of the T1 and of the T2 TSE measured 2.93 mm and 0.98 mm, respectively, without any dependence on the SENSE factors on the lossy image compression rate. The present study suggests that a SENSE factor of more than 2.5 not be applied in T1 and T2 TSE and that lossy compression not be done where a SENSE of 1.5∼ more factor is given in the use of JPEG2000.

저자장 자기공명영상시스템에서 선주사확산강조영상기법 개발

홍철표(Cheolpyo Hong),이동훈(Donghoon Lee),이도완(Dowan Lee),이만우(Manwoo Lee),백문영(Munyoung Paek),한봉수(Bongsoo Han) 한국방사선학회 2008 한국방사선학회 논문지 Vol.2 No.2

0.32 T 자기공명영상시스템에서 선주사영상기법(line scan imaging)을 이용한 확산강조영상(diffusion weighted imaging; DWI) 펄스열(pulse sequence)을 개발하였다. 선주사영상은 단면선택 경사자장과 함께 90도 펄스를 가하여 단면을 선택한 후 y 방향으로 경사자장을 가한 후 180도 라디오파 펄스를 가하여 단면영상의 y-방향 픽셀크기와 같은 너비의 x축에 평행한 띠를 따라 에코가 발생하게 한 뒤 x-방향으로 주파수부호화해서 1차원 k-공간 데이터를 획득하며 이를 1차원 푸리에변환하여 영상을 재구성하였다. 또한 선주사확산강조영상(line scan diffusion weighted image)을 위해서 한 쌍의 사다리꼴모양의 경사자장을 선주사영상기법의 180도 펄스 전후에 대칭으로 배치하였으며 사용된 확산경사자장기울기의 최대값은 G = 15 mT/m 이었고 최대 b 값은 301.50 s/㎟이었다. 본 연구에서 개발된 선주사확산강조펄스열을 이용하여 0.32 T 자기공명영상 장비에서 트리아실글리세롤 팬텀(triacylglycerol, TAG) 및 염화나트륨 수용액 (NaCl = 0.1w/v%) 팬텀 영상을 획득하였다. 또한 1.5 T 자기공명영상시스템에서 단일여기에코평면영상화(single shot echo planar imaging)로 동일한 팬텀의 확산강조영상을 구하였다. 선주사확산강조영상은 가장 널리 이용되고 있는 에코평면영상을 이용한 확산강조영상과 비교하여 자화율차이에 의한 영상왜곡이나 화학이동에 의한 허상들이 없음을 확인하였다. 특히 선주사확산강조영상에서 측정한 염화나트륨 수용액 팬텀의 확산계수(963.90 ± 79.83 ×10¯⁶ ㎟/s)는 1.5 T에서 계산된 확산계수(956.77 ± 4.12 × 10¯⁶ ㎟/s)와 오차범위 내에서 일치하였다. Line scan diffusion weighted imaging (LSDI) pulse sequence for 0.32 T magnetic resonance imaging (MRI) system was developed. In the LSDI pulse sequence, the imaging volume is formed by the intersection of the two perpendicular planes selected by the two slice-selective π/2-pulse and π-pulse and two diffusion sensitizing gradients placed on the both side of the refocusing π-pulse and the standard frequency encoding readout was followed. Since the maximum gradient amplitude for the MR system was 15 mT/m the maximum b value was 301.50 s/㎟. Using the developed LSDI pulse sequence, the diffusion weighted images for the aqueous NaCl solution phantom and triacylglycerol phantom were required at 0.32 T MRI system and analyzed. The mean diffusivity of the aqueous NaCl solution phantom calculated from the line scan diffusion weighted images gives the same results within the standard error range (mean diffusivities = 963.90 ± 79.83 (× 10¯⁶ ㎟/s) at 0.32 T, 956.77 ± 4.12 (× 10¯⁶ ㎟/s) at 1.5 T) and the LSDI images were insensitive to the magnetic susceptibility difference and chemical shift.

Comparison of Noise Power Spectrum Methodologies in Measurements by Using Megavoltage X-ray Energies

민정환,손진현,정회원,김정민,성열훈,Soon-Yong Son,김호경,김상영,이도완,정재용,서태석,최보영 한국물리학회 2012 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.60 No.1

The noise power spectrum (NPS) is one of the most general methods for measuring the noise amplitude and the quality of an image acquired from a uniform radiation field. The purpose of this study was to compare different NPS methodologies by using megavoltage X-ray energies. The NPS evaluation methods in diagnostic radiation were applied to therapy using the International Electrotechnical Commission standard (IEC 62220-1). In order to measure the region of interest (ROI) of the NPS, we used the following five factors: the overlapping impact, the non-overlapping impact, the penumbra, the flatness and different ROI sizes. We used NPS from four different types of detectors,the CR-IP (computed radiography image plate: photo-stimulable phosphor screen), the CR-IP-lead (hexalon lead screen), the CR-IP-back [lanex TM fast back screen: {terbium-doped gadolinium oxysulfide granular phosphor screen (Gd2O2S:Tb,133 mg/cm2)} + 1-mm-thick copper plate] and the CR-IP-front (lanex TM fast front screen). A Kodak 2000 RT photo-stimulable phosphor-based computed radiographic (CR) system showed that the normalized noise power spectrum (NNPS)curve gradually decreased, in compliance with increasing spatial resolution. In addition, each detector showed a different reactivity of the NPS to megavoltage. The results of multivariate analysis of variance (MANOVA) test (methods × detectors) revealed significant main effects of the methods [F(1, 4) = 53.543, P = 0.001] and of the detectors [F(1, 4) = 17.556, P = 0.001]. The present study revealed that various factors could be employed to produce megavoltage imaging (MVI) of the NPS and as a baseline standard for NPS control in MVI.

텅스텐 엣지 블록을 이용하여 Megavoltage (MV) 영상의 질 평가

민정환,손진현,김기원,이정우,손순룡,백금문,김정민,김연래,정재용,김상영,이도완,최보영,Min, Jung-Whan,Son, Jin-Hyun,Kim, Ki-Won,Lee, Jung-Woo,Son, Soon-Yong,Back, Geum-Mun,Kim, Jung-Min,Kim, Yeon-Rae,Jung, Jae-Yong,Kim, Sang-Young,Lee, Do- 한국의학물리학회 2012 의학물리 Vol.23 No.3

최근 백만 볼트 영상(megavoltage imaging, MVI)에서 급격히 발전해 온 디지털 방사선영상(digital radiography, DR)은 치료용 방사선영상 기술이 발전함에 따라 매우 정확하면서 간단하게 측정할 수 있는 일반적인 정도관리(quality assurance, QA) 방법을 요구하게 되었다. 본 연구의 목적은 일반적인 QA 방법과 computed radiography (CR) 장비를 사용하여 MVI의 변조전달함수(modulation transfer function, MTF), 잡음전력스펙트럼(noise power spectrum, NPS), 양자검출효율(detective quantum efficiency, DQE)를 평가하고자 하였다. 텅스텐으로 구성된 $19{\times}10{\times}1cm^3$ 두께의 엣지(edge) 블록을 사용하였으며, 6 MV energy를 사용하였다. 또한 검출기는 CR-IP (image plate), CR-IP-lead, the CR-IP-back (lanex TM fast back screen), CR-IP-front (lanex TM fast front screen)를 사용하였으며, pre-sampling MTF를 계산하였다. CR-IP의 MTF는 0.70 lp/mm를 나타내었고, CR-IP front의 MTF는 1.10 lp/mm로서 가장 높은 값의 고해상도 공간분해능을 보였다. 가장 우수한 검출기의 NPS는 CR-IP front screen에서 확인되었다. 공간주파수가 증가함에 따라 1.0 cycles/mm의 가까운 DQE를 획득하였다. 본 연구결과로서 자체 제작한 엣지 블록 방법은 MVI의 MTF, NPS, DQE를 평가하는 일반적인 QA 방법으로 사용될 수 있음을 확인하여 주었다. Digital Radiography (DR) has rapidly developed in megavoltage X-ray imaging (MVI). Thus, a very simple and general quality assurance (QA) method is required. The purpose of this study was to evaluate the modulation transfer function (MTF), the noise power spectrum (NPS) and the detective quantum efficiency (DQE) for MVI using general QA method and computed radiography (CR) device. We used tungsten edge block with $19{\times}10{\times}1cm^3$ thickness and 6MV energy. For detector, CR-IP (image plate), CR-IP-lead, the CR-IP-back (lanex TM fast back screen), CR-IP-front (lanex TM fast front screen) were used and pre-sampling MTF was calculated. The MTF of CR-IP-front showed the highest value with 1.10 lp/mm although the CR-IP showed the only 0.70 lp/mm. The best NPS was observed in CR-IP front screen. According to the increase in spatial frequency, our results showed that DQE was approximately 1.0 cycles/mm. The present study demonstrates that the QA method with our home-made edge block can be used to evaluate MTF, NPS and DQE for MVI.

Performance of an Edge Block Used in a Configuration Detector: Image Quality Measurements

Jung-Whan Min,김기원,성열훈,김정민,최인석,정회원,손순영,김상영,이도완,최보영 한국물리학회 2014 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.64 No.5

In megavoltage X-ray imaging (MVI), computed radiography (CR) has required a very simple andgeneral quality assurance (QA) method based on a radiotherapy imaging technique. The purposeof this study was to develop a general QA method for evaluating the modulation transfer function(MTF), the noise power spectrum (NPS) and the detective quantum efficiency (DQE) for MVI. Thus, a simple and compact edge block made of tungsten, with dimensions of 19 × 10 × 1 cm3,was efficiently designed and developed. The pre-sampling MTF was evaluated with the followingsettings: a 6 megavoltage (MV) energy, four different types of detectors, CR-IP (image plate:photo-stimulable phosphor screen), CR-IP-Lead (image plate + lead screen), CR-IP-Regular (fastfront screen + image plate + fast front screen) and CR-IP-Fast (fast back screen + image plate +fast front screen). The MTF values at 1 mm−1 for CR-IP-Regular showed the highest resolutionof 0.18. The best noise distribution was observed in the measurement of the NPS with CR-IPRegular. With increasing spatial frequency, our results showed that value of the DQE for the fourtypes of detectors was approximately 1.0 mm−1, which is comparable to the values reported in theliterature. In this report, measurements for megavoltage imaging based on line-pair modulationsby using an edge block are presented. When the wide side of the tungsten block was reduced, theaccuracy of the edge measurement was improved to match those offered by edge techniques. Thepresent study demonstrates that the QA method with our home-made edge block can be used toevaluate the MTF, NPS and DQE for MVI.