• Title/Summary/Keyword: Chemical imaging

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Radioimmunotherapy in Head and Neck Cancer (두경부암에서 방사면역치료의 역할)

  • Choi, Ik Joon
    • Korean Journal of Otorhinolaryngology-Head and Neck Surgery
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    • v.61 no.12
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    • pp.637-643
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    • 2018
  • Radioimmunotherapy (RIT) is a therapy that takes advantage of the "cross-fire" effect of emitted radiation by radionuclides conjugated to tumor-directed monoclonal antibodies (mAb) (including those fragments) or peptides. While RIT has been successfully employed for the treatment of lymphoma, mostly with radiolabeled antibodies against CD20 [$^{90}yttrium$ ($^{90}Y$)-ibritumomab tiuxetan; $Zevalin^{(R)}$ and $^{131}iodine$ ($^{131}I)-tositumomab$; $Bexxar^{(R)}$], its use in solid tumors is more challenging, so far. Immuno-PET, a tool for tracking and quantification of mAbs with PET in vivo, is an exciting novel option to improve diagnostic imaging and guide mAb-based therapy. RIT in solid tumors including head and neck cancer may be an alternative treatment with advances in various biological, chemical, and treatment procedures, and it may help to reduce unnecessary exposure and enhance the therapeutic efficacy. Also, immuno-PET based on RIT might play an important role in cancer staging, in patients or targets selection of targeted therapeutics and in monitoring the response of targeted therapeutics as precision medicine. In this review, fundamentals of RIT/immune-PET and current knowledge of the preclinical/clinical trials in RIT for solid tumor including head and neck cancer are reviewed.

Deep Impact: Molecular Gas Properties under Strong Ram Pressure Probed by High-Resolution Radio Interferometric Observations

  • Lee, Bumhyun;Chun, Aeree
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.2
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    • pp.39.3-39.3
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    • 2019
  • Ram pressure stripping due to the intracluster medium (ICM) is an important environmental process, which causes star formation quenching by effectively removing cold interstellar gas from galaxies in dense environments. The evidence of diffuse atomic gas stripping has been reported in several HI imaging studies. However, it is still under debate whether molecular gas (i.e., a more direct ingredient for star formation) can be also affected and/or stripped by ram pressure. The goal of this thesis is to understand the impact of ram pressure on the molecular gas content of cluster galaxies and hence star formation activity. To achieve this, we conducted a series of detailed studies on the molecular gas properties of three Virgo spiral galaxies with clear signs of active HI gas stripping (NGC 4330, NGC 4402, and NGC 4522) based on high-resolution CO data obtained from the Submillimeter Array (SMA) and Atacama Large Millimeter/submillimeter Array (ALMA). As a result, we find the evidence that the molecular gas disk also gets affected by ram pressure in similar ways as HI even well inside of the stellar disk. In addition, we detected extraplanar 13CO clumps in one of the sample, which is the first case ever reported in ram pressure stripped galaxies. By analyzing multi-wavelength data (e.g., Hα, UV, HI, and CO), we discuss detailed processes of how ram pressure affects star formation activities and hence evolution of cluster galaxies. We also discuss the origin of extraplanar 13CO, and how ram pressure can potentially contribute to the chemical evolution of the ICM.

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The Effect of Nuclear Overhauser Enhancement in Liver and Heart $^{31}P$ NMR Spectra Localized by 2D Chemical Shift Technique (이차원 화학변위 기법을 이용한 간 및 심장 $^{31}P$ 자기공명분광에서의 Nuclear Overhauser 효과에 대한 연구)

  • Ryeom Hun-Kyu;Lee Jongmin;Kim Yong-Sun;Lee Sang-Kwon;Suh Kyung-Jin;Bae Sung-Jin;Chang Yongmin
    • Investigative Magnetic Resonance Imaging
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    • v.8 no.2
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    • pp.94-99
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    • 2004
  • Purpose : To investigate the signal enhancement ratio by NOE effect on in vivo $^{31}P$ MRS in human heart muscle and liver. we also evaluated the enhancement ratios of different phosphorus metabolites, which are important in 31P MRS for each organ. Materials and Methods : Ten normal subjects (M:F = 8:2, age range = 24-32 yrs) were included for in vivo $^{31}P$ MRS measurements on a 1.5 T whole-body MRI/MRS system using $^1H-^{31}P$ dual tuned surface coil. Two-dimensional Chemical Shift Imaging (2D CSI) pulse sequence for $^{31}P$ MRS was employed in all $^{31}P$ MRS measurements. First, $^{31}P$ MRS performed without NOE effect and then the same 2D CSI data acquisitions were repeated with NOE effect. After postprocessing the MRS raw data in the time domain, the signal enhancements in percent were estimated from the major metabolites. Results : The calculated NOE enhancement for liver $^{31}P$ MRS were $\alpha-ATP\;(7\%),\;\beta-ATP\;(9\%),\;\gamma-ATP\;(17\%),\;Pi\;(1\%),\;PDE\;(19\%)$ and $PME\;(31\%)$. Because there is no creatine kinase activity in liver, PCr signal is absent. For cardiac $^{31}P$ MRS, whole body coil gave better scout images and thus better localization than surface coil. In $^{31}P$cardiac multi-voxel spectra, DPG signal increased from left to right according to the amount of blood included. The calculated enhancement for cardiac $^{31}P$ MRS were : $\alpha-ATP\;(12\%),\;\beta-ATP\;(19\%),\;\gamma-ATP\;(30\%),\;PCr\;(34\%),\;Pi\;(20\%),\;(PDE)\;(51\%),\;and\;DPG\;(72\%)$. Conclusion : Our results revealed that the NOE effect was more pronounced in heart muscle than in liver with different coupling to 1H spin system and thus different heteronuclear cross-relaxation.

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Preparation and Mechanical Properties of Bulk Molding Compound Composite Prepared using Recycled FRP Waste Powder (폐FRP 미분말을 재활용한 BMC 복합재료의 제조 및 기계적 물성)

  • Hwang, Eui-Hwan;Jeon, Jong-Ki
    • Applied Chemistry for Engineering
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    • v.21 no.2
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    • pp.217-223
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    • 2010
  • In general, fiber-reinforced plastics (FRP) wastes are simply buried or burned. Landfill brings about a permanent contamination of soil due to the inability of FRP to decompose and incineration causes an issue of generating toxic gases and dusts. There have been several ways to treat the FRP wastes such as landfill, incineration, chemical recycling, material recycling and the utilization of energy from combustion. Most methods excluding material recycling are known to have critical limitations in economic, technical and environmental manners. However it is known that material recycling is most desirable among the methods handling FRP wastes. In this study, to investigate the purpose of feasibility of material recycling, various bulk molding compound (BMC) specimens were prepared with the various contents of unsaturated polyester resin binder (25, 30, 35 wt%) and the various replacement ratios of FRP wastes powder (0, 25, 50, 75, 100 wt%) substituted for filler. To evaluate the physical properties BMC specimens, various tests such as tensile strength, flexural strength, impact strength, hot water resistance and SEM imaging were conducted. As a results, mechanical strengths decreased with an increase of replacement ratio of FRP waste powder and physical properties of BMC specimens were deteriorated in the hot water resistance. The fluidity of BMC with more than 50 wt% of the replacement ratio of FRP wastes powder decreased remarkably, causing a problem in the BMC composite.

Synthesis and Small Animal Brain PET Study of a Serotonin Receptor Radiotracer, 18F-Mefway (세로토닌 5-HT1A수용체 방사성 추적자 18F-Mefway의 합성과 소동물 뇌 PET 연구)

  • Ahn, Sung-Min;Hong, Tae-Kee;Ryu, Young-Hoon;Choi, Jae-Yong;Kim, Sung-Chul
    • The Journal of the Korea Contents Association
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    • v.9 no.11
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    • pp.262-270
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    • 2009
  • $^{18}F$-mefway has been developed as radioligand for serotonin receptor 5-$HT_{1A}$. The object of this study was to obtain the mefway precursor with the higher yield than previous method and to identify whether $^{18}F$-mefway can bind to 5-$HT_{1A}$ or not. from microPET imaging of small animal brain. Precursor was prepared by a modification of the reported procedure then [$^{18}F$] labeling was performed by adding $^{18}F$ ion at $130^{\circ}C$ in the hot cell for 30min. After purification of reaction mixture using alumina Sep-pak and HPLC, microPET images of small animal brain were determined. The chemical yield of precursor was increased from 9% to 34% using oxalyl chloride and LAH/diethylether. We synthesized a precursor which was successfully labeled with no-carrier-added $^{18}F$-by new synthetic route. This research suggest that $^{18}F$-mefway will be used a radiopharmaceutical for evaluation of central nerve system disorder as imaging a gent for 5-$HT_{1A}$ receptor.

The Accuracy of the Radiographic Method in Root Canal Length Measurement (근광장 측정에서 방사선 사진술의 정확도)

  • Jo Eun-Young;Park Chang-Seo
    • Journal of Korean Academy of Oral and Maxillofacial Radiology
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    • v.28 no.2
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    • pp.471-489
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    • 1998
  • For the successful endodontic treatment, root canal should be cleaned thoroughly by accurate mechanical and chemical canal preparation and sealed completely with canal filling material without damaging the periapical tissues. The accuracy of the root canal length measurement is a prerequisite for the success of the endodontic treatment, and the root canal length is often determined by the standard periapical radiographs and digital tactile sense. In this study, the accuracy and the clinical usefulness of Digora/sup (R)/, an intraoral digital imaging processor and the conventional standard radiographs were compared by measuring the length from the top of the file to the root apex. 30 single rooted premolars were invested in a uniformly sized blocks and No.25 K-file was inserted into and fixed in each canal. Each block was placed in equal distance and position to satisfy the principle of the bisecting angle and paralleling techniques and Digora/sup (R)/ system's image and standard periapical radiographs were taken. Each radiograph was examined by 3 different observers by measuring the length from top of the file to the root apex and each data was compared and analyzed. The results were as follows; 1. In the bisecting angle technique, the average difference between the Digora/sup (R)/ system and standard periapical radiograph was 0.002 mm and the standard deviation was 0.341 mm which showed no statistically significant difference between the two systems(p>0.05). Also, in the paralleling technique, the average difference between these two system was 0.007 mm and the standard deviation was 0.323 mm which showed no statistically significant difference between the two systems(p>0.05). 2. In Digora/sup (R)/ system, the average difference between the bisecting angle and paralleling technique was -0.336 mm and the standard deviation was 0.472 mm which showed a statistically significant difference between the two techniques(p<0.05). Also, in the standard periapical radiographs, the average difference between the bisecting angle and paralleling technique was 0.328 mm and the standard deviation was 0.517 mm which showed a statistically significant difference between these two techniques(p<0.05). 3. In Digora/sup (R)/ system and the standard periapical radiographs. there was a statistically significant difference between the measurement using the bisecting angle technique and the actual length(p<0.05), But there was no statistically significant difference between the measurement using the paralleling technique and the actuallength(p>0.05). In conclusion. the determination of the root canal length by using the Digora/sup (R)/ system can give us as good an image as the standard periapical radiograph and using the paralleling technique instead of the bisecting angle technique can give a measurement closer to the actual canal length. thereby contributing to a successful result. Also. considering the advantages of the digital imaging processor such as decreasing the amount of exposure to the patient. immediate use of the image. magnification of image size. control of the contrast and brightness and the ability of storing the image can give us good reason to replace the standard periapical radiographs.

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Assesment Of Image Quality in the Abdominal Magnetic Resonance Imaging: Comparison with 1.5 T and 3.0 T (복부 자기공명영상에서 영상의 질 평가: 1.5 T 와 3.0 T 비교)

  • Goo, Eun-Hoe
    • Journal of the Korean Society of Radiology
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    • v.10 no.5
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    • pp.367-373
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    • 2016
  • This study conducted an analysis to compare the differences in the properties of the magnetic field and the generation of artifacts because of the difference in the magnetic field between 1.5 T equipment and 3.0 T equipment, centering around four types of pulse sequences, mainly applied to the abdominal Magnetic Resonance Imaging (MRI). With data on 500 persons transmitted to the PACS, this study analyzed the SNR value, quantitatively and carried out a qualitative evaluation, dividing MSA, CSA, and DA into three steps. As a result of the quantitative evaluation, the SNR value was significantly higher in the 1.5 T equipment; however, there was a factor deteriorating the image quality, too, as artifacts were generated in the images. The 1.5 T equipment generated fewer artifacts than the 3.0 T equipment did, so it could compensate the image quality for 3.0 T. In conclusion, based on these findings, this study could understand the differences in the properties of the magnetic field and the generation of artifacts occurring because of the difference in the magnetic field and could provide a measure for them. This study would be guidelines for MRI users who directly examine the patients in abdominal MRI using the two types of equipment in the clinical setting in the future.

Analysis of Polymer Characteristics Using Matrix-assisted Laser Desorption/Ionization Time-of-flight Mass Spectrometry (말디토프 질량분석을 이용한 고분자의 특성분석)

  • Kang, Min-Jung;Seong, Yunseo;Kim, Moon-Ju;Kim, Myung Soo;Pyun, Jae-Chul
    • Applied Chemistry for Engineering
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    • v.28 no.3
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    • pp.263-271
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    • 2017
  • The application of mass spectrometry to polymer science has rapidly increased since the development of MALDI-TOF MS. This review summarizes current polymer analysis methods using MALDI-TOF MS, which has been extensively applied to analyze the average molecular weight of biopolymers and synthetic polymers. Polymer sequences have also been analyzed to reveal the structures and composition of monomers. In addition, the analysis of unknown end-groups and the determination of polymer concentrations are very important applications. Hyphenated techniques using MALDI-tandem MS have been used for the analysis of fragmentation patterns and end-groups, and also the combination of SEC and MALDI-TOF MS techniques is recommended for the analysis of complex polymers. Moreover, MALDI-TOF MS has been utilized for the observation of polymer degradation. Ion mobility MS, TOF-SIMS, and MALDI-TOF-imaging are also emerging technologies for polymer characterization because of their ability to automatically fractionate and localize polymer samples. The determination of polymer characteristics and their relation to the material properties is one of the most important demands for polymer scientists; the development of software and instrument for higher molecular mass range (> 100 kD) will increase the applications of MALDI-TOF MS for polymer scientists.

Selective Pattern Growth of Silica Nanoparticles by Surface Functionalization of Substrates (기판 표면 기능화에 의한 실리카 나노입자의 선택적 패턴 성장)

  • Kim, Ki-Chul
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.4
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    • pp.20-25
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    • 2020
  • As nanoscience and nanotechnology advance, techniques for selective pattern growth have attracted significant attention. Silica nanoparticles (NPs) are used as a promising nanomaterials for bio-labeling, bio-imaging, and bio-sensing. In this study, silica NPs were synthesized by a sol-gel process using a modified Stöber method. In addition, the selective pattern growth of silica NPs was achieved by the surface functionalization of the substrate using a micro-contact printing technique of a hydrophobic treatment. The particle size of the as-synthesized silica NPs and morphology of selective pattern growth of silica NPs were characterized by FE-SEM. The contact angle by surface functionalization of the substrate was investigated using a contact angle analyzer. As a result, silica NPs were not observed on the hydrophobic surface of the OTS solution treatment, which was coated by spin coating. In contrast, the silica NPs were well coated on the hydrophilic surface after the KOH solution treatment. FE-SEM confirmed the selective pattern growth of silica NPs on a hydrophilic surface, which was functionalized using the micro-contact printing technique. If the characteristics of the selective pattern growth of silica NPs can be applied to dye-doped silica NPs, they will find applications in the bio imaging, and bio sensing fields.

Differential Diagnosis of Chemical-induced Hepatobiliary Toxicities Using a New Hepatobiliary Imaging Agent in Mice

  • Ryu, Chong-Kun;Pie, Jae-Eun;Choe, Jae-Gol;Cheon, Joon;Sohn, Jeong-Won;Jurgen Seidel;David S. Paik;Michael V. Green;Chang H. Paik;Kim, Meyoung-Kon
    • Environmental Mutagens and Carcinogens
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    • v.21 no.1
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    • pp.1-8
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    • 2001
  • We have synthesized $^{99m}$Tc-mercaptoacetyltriglycine (MAG3)-biocytin as a new imaging agent for hepatobiliary scintigraphy. The aim of this study was to evaluate the usefulness of $^{99m}$Tc-MAG3-biocytin scintigraphy in differentiating carbon tetrachloride ( $CCl_4$)-induced hepatotoxicity from $\alpha$-naphthylisothiocyanate (ANIT)-induced cholestasis in mice, which reflecting the differential diagnosis of neonatal jaundice caused by neonatal hepatitis from congenital biliary atresia in humans. Methods: Balb/c mice (female, 20 g, n=4-6) were pretreated with $CCl_4$(0.5 or $1.0m\ell$/kg) and ANIT ($150 or 300 m\ell$/kg) 18 h before scintigraphy. Biochemical and histopathological examinations showed a pattern of typical acute hepatitis (increase of transaminases and hepatocellular necnsis) in $CCl_4$-treated mice and cholestasis (increase of alkaline phosphatase and ${\gamma}$-glutamyltransferase, and biliary hyperplasia) in ANIT-treated mice, respectively, Mice were fasted at least 4 hr prior to the intravenous injection of $^{99m}$Tc-MAG3-biocytin (18.5 MBq/20$\mu\textrm{g}$) in 2% human serum albumin in saline. Scintigraphy was performed with a ${\gamma}$-camera equipped with a 1-mm diameter pin-hole collimator for 30 min and images were acquired every 15 s. We compared the values of physical parameters, such as peak liver/heart ratio ($${\gamma}$_{max}$) and peak ratio time ($t_{max}$) far $^{99m}$Tc-MAG3-biocytin scintigraphy. Results: Scintigraphic parameters of the $CCl_4$-pretreated (0.5 $m\ell$/kg) group showed a 81.9% decrease of r$_{max}$, and 42.2% decrease of $t_{max}$, whereas the ANIT-pretreated ( $150m\ell$/kg) group showed a 53% decrease of $r_{max}$, and 2.36-fold increase of $t_{max}$, (P<0.05). These results demonstrate that the decrease of $r_{max}$ and the shortening of $t_{max}$ are characteristic features for hepatotoxicity, in contrast to the increase of $t_{max}$ and decrease of $r_{max}$ for biliary hyperplasia. Conclusion: $^{99m}$Tc-MAG3-biocytin hepatobiliary scintigraphy can distinguish hepatitis from cholestasis in mice model and may be similarly useful in humans which differentiating the cause of neonatal jaundice in clinical study.cal study.cal study.cal study.

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