• Title/Summary/Keyword: Half Life

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Phantom Study of the Mutual Influences Between 18F-FDG and 99mTcO4- on the Same Day (18F-FDG와 99mTcO4-를 이용한 당일 검사 시 상호 영향에 대한 Phantom 연구)

  • Ham, Jun Cheol;Park, Min Soo;Bahn, Young Kag;Lim, Han Sang;Kim, Jae Sam
    • The Korean Journal of Nuclear Medicine Technology
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    • v.18 no.2
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    • pp.68-72
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    • 2014
  • Purpose The nuclear medicine examination, there is a difficulty to carry out the inspection of both on the day of residual isotope due to the half-life. In this study, by studying the mutual influence and $^{18}F$-FDG of $^{99m}TcO_4{^-}$, I would like to explain the matters to be considered in the case of performing the same day. Materials and Methods With the NEMA-1994 Phantom, and experiments were performed 3 times. Create a 1: 4 Background ratio HOT and the $^{99m}TcO_4{^-}$ The first experiment: After underwent SPECT in INFINIA (GE Healthcare, MI, USA), and were injected with $^{18}F$-FDG 37 MBq in the Background area, 13 once for 60 minutes under the same conditions was time Scan. Create a 1: 4 Background ratio HOT and the $^{18}F$-FDG second is: The Scan in PET/CT Discovery 600 (GE Healthcare, MI, USA), and 148 MBq after injection $^{99m}TcO_4{^-}$ the Background area, once for 60 minutes, 6 under the same conditions was time Scan. Create a 1: 4 Background ratio HOT and the $^{18}F$-FDG experiments las, increments of 296 MBq and 148 MBq the 1 Bed Scan after $^{99m}TcO_4{^-}$, was 1 Bed Scan under the same conditions. Non BKG area and HOT, I was measured comparing the Total Counts and SNR or CNR. Results Showed a significant difference in the ratio CNR of enforcement during SPECT $^{18}F$-FDG is, (p>0.05). The $^{99m}TcO_4{^-}$ was no significant difference between the SNR ratio of PET / CT at the time of the effective date (p<0.05). I got the results $^{99m}TcO_4{^-}$ that reduce the Total Counts of PET / CT scan. Conclusion If you make a PET / CT scan, may affect the test using the $^{99m}TcO_4{^-}$ up to 12 hours, when it is performed before the $^{99m}TcO_4{^-}$, does not affect the SNR and SUV, PET / CT scan I reduced the detection efficiency. The inspection of day, we'd like to recommend a way to complement the detection efficiency to increase the inspection time of PET / CT in move forward the inspection using the $^{99m}TcO_4{^-}$.

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Development of Radiosynthetic Methods of 18F-THK5351 for tau PET Imaging (타우 PET영상을 위한 18F-THK5351의 표지방법 개발)

  • Park, Jun-Young;Son, Jeong-Min;Chun, Joong-Hyun
    • The Korean Journal of Nuclear Medicine Technology
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    • v.22 no.1
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    • pp.51-54
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    • 2018
  • Purpose $^{18}F-THK5351$ is the newly developed PET probe for tau imaging in alzheimer's disease. The purpose of study was to establish the automated production of $^{18}F-THK5351$ on a commercial module. Materials and Methods Two different approaches were evaluated for the synthesis of $^{18}F-THK5351$. The first approach (method I) included the nucleophilic $^{18}F$-fluorination of the tosylate precursor, subsequently followed by pre-HPLC purification of crude reaction mixture with SPE cartridge. In the second approach (method II), the crude reaction mixture was directly introduced to a semi-preparative HPLC without SPE purification. The radiosynthesis of $^{18}F-THK5351$ was performed on a commercial GE $TRACERlab^{TM}$ $FX-_{FN}$ module. Quality control of $^{18}F-THK5351$ was carried out to meet the criteria guidelined in USP for PET radiopharmaceuticals. Results The overall radiochemical yield of method I was $23.8{\pm}1.9%$ (n=4) as the decay-corrected yield (end of synthesis, EOS) and the total synthesis time was $75{\pm}3min$. The radiochemical yield of method II was $31.9{\pm}6.7%$ (decay-corrected, n=10) and the total preparation time was $70{\pm}2min$. The radiochemical purity was>98%. Conclusion This study shows that method II provides higher radiochemical yield and shorter production time compared to the pre-SPE purification described in method I. The $^{18}F-THK5351$ synthesis by method II will be ideal for routine clinical application, considering short physical half-life of fluorine-18 ($t_{1/2}=110min$).

Characteristics and Recurrence Risk Factors of Urinary Tract Infection in Early Infancy (6개월 미만 영아 요로 감염의 특성과 재발의 위험 인자)

  • Kang Hee-Gyung;Kim Nam-Hee;Kang Ju-Hyung;Ha Il-Soo;Cheong Hae-Il;Choi Yong
    • Childhood Kidney Diseases
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    • v.8 no.2
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    • pp.223-228
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    • 2004
  • Purpose and Methods: Urinary tract infection(UTI) is one of the most important diseases of childhood, especially for young infants. To characterize the patients diagnosed with febrile UTI in their first 6 months of life and to explore the risk factors of recurrent UTI, a retrospective study was performed. Results: Among the 90 patients studied, 77 were boys(86%). First episodes of UTI were diagnosed at the age of $2.5{\pm}1.4$ months. These patients underwent ultrasonographic evaluation of urinary tract(n=90) and voiding cystourethrography(n=81) where 53 and 35 studies showed abnormal findings respectively, and a total of 45 cases of urinary tract anomaly including vesicoureteral reflux(VUR, n=35) were diagnosed. Normal findings on ultrasonography indicated decreased risk of VUR in boys of 1-3 months of age(n=30). 53 patients were followed up more than 6 months and 45 episodes of subsequent UTI developed in 29 patients during the first 6-month period. Patients with relapse were older than patients without relapse at the diagnosis of first UTI, but other clinical parameters including abnormal findings on the imaging studies and prophylactic antibiotics prescription were not different between the two groups. Conclusion: UTI in early infancy occurred mainly in male infants and half of the patients had structural anomalies. USG was of clinical value in detecting anomalies requiring surgical intervention, and to rule out high grade VUR in 1-3 months old boys. Results of the imaging study or prophylactic antibiotics could not modify the risk of recurrent UTI. (J Korean Soc Pediatr Nephrol 2004;8:223-228)

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A Study on the Synthesis and Its Biodistribution of C-11 and F-18 Labelled Choline (C-11 및 F-18 표지 콜린의 합성과 체내동태에 관한 연구)

  • Yang, Seung-Dae;Kim, Sang-Wook;Suh, Yong-Sup;Chun, Kwon-Soo;Ahn, Soon-Hyuk;Hur, Min-Goo;Lim, Sang-Moo;Hong, Sung-Woon;Yu, Kook-Hyun
    • The Korean Journal of Nuclear Medicine
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    • v.35 no.3
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    • pp.185-191
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    • 2001
  • Objectives: Recently, $[methyl-^{11}C]-({\beta}$-Hydroxyethyl)trimethylammonium ($[^{11}C]$choline) Has been discovered to be a very effective tracer in imaging various human tumors using positron omission tomography. Because of the short half-life of C-11, it is very difficult to use in a routine imaging procedure and needs a frequent synthesis of $[^{11}C]$choline. This can be supplemented by the substitution of $[^{11}C]$choline with $[methyl-^{18}F]$fluorocholine. Here, we would like to report ceil uptake and biodistribution of $[^{11}C]$choline and $[^{18}F]$fluorocholine as a basic study. Methods: $[^{11}C]$Choline was prepared by the treatment of $[^{11}C]CH_3I$ with N,N-dimethylaminoethanol and $[^{18}F]$fluorocholine was synthesized from reaction of $CH_2Br[^{18}F]F$ with N,N-dimethylaminoethanol. The radiochemical purity was checked by high performance liquid chromatography (HPLC). The blodistribution of $[^{11}C]$choline and $[^{18}F]$fluorocholine was determined in balb/c mouse at 5 min, 20 min, 40 min and 80 min. The cell uptake was measured using glioma (9L) and colon adenocarcinoma (SW620). Results: The radiochemical purity was more than 98% after purification. In the liver, uptake did not change over time; the uptake was 20%ID/g for $[^{11}C]$choline and 13%ID/g for $[^{18}F]$fluorocholine. In the kidney, radioactivity decreased over time; the uptake was 15%ID/g for $[^{11}C]$choline and 20%ID/g for $[^{18}F]$fluorocholine, 80 min post-injection. The cell uptake of $[^{11}C]$choline was 4.93% for glioma (9L) and 18.69% for colon adenocarcinoma (SW620). For $[^{18}F]$fluorocholine, 1.77% for glioma (9L) and 2.77% for colon adenocarcinoma (SW620). Conclusion: $[^{11}C]$Choline and $[^{18}F]$fluorocholine showed a different cell uptake tendency, depending on cancer cell line.

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Antimicrobial Effects against Food-Borne Pathogens and Antioxidant Activity of Rhododendron brachycarpum Extract (만병초 추출물의 식중독 유발균에 대한 항균효과 및 항산화활성)

  • Choi, Moo-Young;Rhim, Tae-Jin
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.40 no.10
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    • pp.1353-1360
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    • 2011
  • This study was performed to investigate the antimicrobial effects against food-borne pathogens and antioxidant activity of Rhododendron brachycarpum ethanol-extract. The antimicrobial activity of the extract was determined using a paper disc-diffusion method, and the diameter of the clear zone was measured. The diameter of the clear zone in the presence of 10 mg of extract was maximal against Bacillus cereus among the three tested Gram-positive bacteria and against Escherichia coli O157:H7 among the five tested Gram-negative bacteria. Analysis of the minimum inhibitory concentration (MIC) showed that the extract exhibited a similar efficacy as that of sorbic acid, a well-known chemical preservative. The growth inhibitory effects of the extract at concentrations of 250, 500, 1,000, and 2,000 mg/L on food-borne pathogens were determined against Staphylococcus aureus, Listeria monocytogenes, Salmonella Typhimurium, and Escherichia coli O157:H7. Growth of the microorganisms was not affected by the extract at concentrations up to 250 mg/L, but it was significantly (p<0.05) inhibited by the extract at concentrations higher than 1,000 mg/L. The antioxidant effects of the extract were examined via measurement of DPPH radical scavenging activity, inhibition of reactive oxygen species (ROS) generation using fluorescent dichlorofluorescien (DCF) assay, and prevention of peroxyl radical- and hydroxyl radical-induced supercoiled DNA breakage. The $IC_{50}$ of the extract for DPPH radical scavenging activity was about half that of ${\alpha}$-tocopherol, which was used as a positive control. DCF fluorescence intensity decreased as the concentration of the extract increased, demonstrating that ROS generation was inhibited in a concentration-dependent manner. The ROS inhibitory effect of the extract was higher than that of ascorbic acid. The extract prevented supercoiled DNA strand breakage induced by peroxyl radical and hydroxyl radical. Thus, the results of the present study demonstrate that the extract exhibits antimicrobial effects against food-borne pathogens as well as potent antioxidant capacity, suggesting that R. brachycarpum could be used as a natural antibacterial agent and effective antioxidant in food.

Detection and Measurement of Nuclear Medicine Workers' Internal Radioactive Contamination (핵의학과 종사자의 방사성동위원소 체내오염 측정)

  • Jeong, Gyu-Hwan;Kim, Yong-Jae;Jang, Jeong-Chan;Lee, Jai-Ki
    • The Korean Journal of Nuclear Medicine Technology
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    • v.13 no.3
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    • pp.123-131
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    • 2009
  • Purpose: We tested a sample of nuclear medicine workers at Korean healthcare institutions for internal contamination with radioactive isotopes, measuring concentrations and evaluating doses of individual exposure. Materials and Methods: The detection and measurement was performed on urine samples collected from 25 nuclear medicine workers at three large hospitals located in Seoul. Urine samples were collected once a week, 100~200 mL samples were gathered up to 6~10 times weekly. A high-purity germanium detector was used to measure gamma radiations in urine samples for the presence of radioactive isotopes. Based on the detection results, we estimated the amounts of intake and committed effective doses using IMBA software. In cases where committed effective doses could not be adequately evaluated with IMBA software, we estimated individual committed effective doses for radionuclides with a very short half life such as $^{99m}Tc$ and $^{123}I$, using the methods recommended by International Atomic Energy Agency. Results: Radionuclides detected through the analysis of urine samples included $^{99m}Tc$, $^{123}I$, $^{131}I$ and $^{201}Tl$, as well as $^{18}F$, a nuclide used in Positron Emission Tomography examinations. The committed effective doses, calculated based on the radionuclide concentrations in urine samples, ranged from 0 to 5 mSv, but were, in the majority of cases, less than 1 mSv. The committed effective dose exceeded 1 mSv in three of the samples, and all three were workers directly handling radioactive sources. No nurses were found to have a committed effective dose in excess of 1 mSv. Conclusions: To improve the accuracy of results, it may be necessary to conduct a long-term study, performed over a time span wide enough to allow the clear determination of the influence of seasonal factors. A larger sample should also help increase the reliability of results. However, as most Korean nuclear medicine workers are currently not necessary to monitored routinely for internal contamination with radionuclides. Notwithstanding, a continuous effort is recommended to reduce any unnecessary exposure to radioactive substances, even if in inconsequential amounts, by regularly surveying workplace environments and frequently monitoring atmospheric concentrations of radionuclides.

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Thermal Stability of Israeli Carp Actomyosin and Its Protection by Chemical Additives (이스라엘 잉어 Actomyosin의 열안정성과 그 보호)

  • NAM Taek-Jeong;CHOI Yeung-Joon;PYEUN Jae-Hyeung
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.17 no.4
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    • pp.271-279
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    • 1984
  • Effects of temperature and additives on the stability of actomyosin extracted from skeletal muscle of Israeli carp, Cyprinus carpio nudus, were studied by analyzing free SH-group, ATP-sensitivity and Ca-ATPase activity. The used additives were sucrose, sorbitol, Na-glutamate and L-cysteine. Furthermore, the denaturation constant($K_D$), protective effect(${\Delta}E/M$) and the other thermo-dynamic parameters on protein denaturation are systematically discussed. The actomyosin showed $4.12{\sim}4.68 mg/ml$ in protein concentration, $2.63{\sim}2.93\%$ in ribonucleic acid to the protein, $1:2.20{\sim}2.63$ in the binding ratio of myosin and actin, $4.33{\sim}5.26\%$ in fat content, 109.78 in ATP-sonsitivity, $0.159{\sim}0.201\;{\mu}M-Pi/min/mg-protein$ in Ca-ATPase activity and $3.3{\sim}3.4M/10^5$g-protein in free SH-group content. The first-order rate plots were obtained on the decrease of Ca-ATPase activity and ATP-sensitivity with an increase in temperature, while the free SH-group was increased to $60^{\circ}C$ and decreased rapidly above the temperature. The half-life of Ca-ATPase activity on the actomyosin Ca-ATPase was 280 min at $12^{\circ}C$, 125 min at $20^{\circ}C$, 55 min at $30^{\circ}C$ and 13 min at $40^{\circ}C$, and activation energy, activation enthalpy, activation entropy and free energy of the proteins at $20^{\circ}C$ wene 5,395 cal/mole, 4,814 cal/mole, -40.42 e.u. and 17,626 cal/mole, respectively. The protective effect of the additives on the actomyosin Ca-ATPase showed that the most effective material is $3\%$ sorbitol and followed in the order of $8\%$ Na-glutamate, $1\%$ sucrose and $1\%$ L-cysteine. The actomyosin was more stable at $-30^{\circ}C$ than at $0^{\circ}C$ and $-20^{\circ}C$. and when the additives were used in the low temperature storage, $8\%$ Na-glutamate was the most effective. $3\%$ sorbitol, $1\%$ sucrose and $1\%$ L-cysteine was to become lower in the order.

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A Case Study about Counting Uncertainty of Radioactive Iodine (131I) in Public Waters by Using Gamma Spectrometry (감마분광분석을 이용한 환경 중 방사성요오드(131I)의 측정 불확도에 관한 사례 연구)

  • Cho, Yoonhae;Seol, Bitna;Min, Kyoung Ok;Kim, Wan Suk;Lee, Junbae;Lee, Soohyung
    • Journal of Korean Society of Environmental Engineers
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    • v.38 no.1
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    • pp.42-46
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    • 2016
  • The radioactive iodine ($^{131}I$) presents in the environment through the excrete process of nuclear medicine patients. In the detecting of low level of $^{131}I$ in the public water, the counting uncertainty has an effect on the accuracy and reliability of detecting $^{131}I$ radioactivity concentration. In this study, the contribution of sample amount, radioactivity concentration and counting time to the uncertainty was investigated in the case of public water sample. Sampling points are public water and the effluents of a sewage treatment plant at Sapkyocheon stream, Geumgang river. In each point, 1, 10 and 20 L of liquid samples were collected and prepared by evaporation method. The HPGe (High Purity Germanium) detector was used to detect and analyze emitted gamma-ray from samples. The radioactivity concentration of $^{131}I$ were in the range of 0.03 to 1.8 Bq/L. The comparison of the counting uncertainty of the sample amount, 1 L sample is unable to verify the existence of the $^{131}I$ under 0.5 Bq/L radioactivity concentration. Considering the short half-life of $^{131}I$ (8.03 days), a method for measuring 1 L sample was used. However comparing the detecting and preparing time of 1, 10 L respectively, detecting 10 L sample would be an appropriate method to distinguish $^{131}I$ concentration in the public water.

A Study on the Comparative Art theory in the Arts and Crafts Movement and Post-impressionism (미술 공예 운동과 후기 인상주의 비교 예술론 연구)

  • 박연실
    • Archives of design research
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    • v.20
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    • pp.279-291
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    • 1997
  • The history of modern design begins with the arts and crafts movement(1860). The importance of the movement which decorated the outset gave birth to all the trends of thought which would occur under the circumstances within it, and is deemed that the ideas of the figures who played an active part in the movement might be ceaselessly continued through the works and ideas of their outstanding juniors or purpils as a doctrine of the philosophy of design. Therefore, it might be a prerequisite that the significance and spirit of the movement, and its developing process should be addressed in detail in the first place, but for the limited space of this paper, it was intended to desvribe only the part which can be interpreted in duplicate, linked with post-impressionism. The subject of this thesis is about a theory of art in which both ideas of the movement(1860) and the post-impressionism(1910) are comparatively reviewed. The genre, strictly speaking, is classified into the history of painting, and there is a gap fo about an half century between the issues which are comparatively discussed here. Both the movements began in a same environmental place of England, specially the movement at Milieu in England, and since there is a common point that the representative runners of each movement, William Morries(1834-1896) and Roger Fry(1866-1934), belong to a same race of Engol-Saxon, their ideas coincide with an aesthetic scholar, H. Tanie's aesthetic interpretation method and the more important is, as being elucidated in the comment and aesthetic theory for which Roger Fry gave effort and activity in his later life, that when he read intensively Ruskin's books, $\ulcorner$Modern Painters$\lrcorner$and$\ulcorner$Stones of Venice$\lrcorner$he had solidified his idea of post-impressionism while giving approval and criticism on them. After all, as in a co-painter, Windyham Lewis's reference of 'Roger Fry's Too Late Morris Movement', he, inspired by the actual activities of Morris, played activities similar to that of Morris in which exhibiting and selling some of his decorative art works signed by him and the works of post-impressionism through (1913-1920). Herein, that is wished to add a remark by this author is a point that the author of$\ulcorner$Vision and Design$\lrcorner$, Roger Fry, has not be made a subject of discussion specially in the Korean world of design. So, with this case of a thesis, it's wished that many latent awakened, design persons in korea give efforts to researching into Roger Fry so that their findings could be officially announced in the would. By the way, what is tried to describe in this paper from now on is to analyse and review the origin of post-impressionism which idea was first coined in the art world through the 1st and 2nd exhibitions of 'Manet and Post-impressionism' which were opened each at the Grafton Gallery in 1910 and 1913 by him. And also, it is intended to review it through the art journals and some references by critics of the day in which favorable criticism or severe criticism were ready to comment through the opinions and influences of the coworkers of Roger Fry, say, Clive Bell, Desmond Maccarthy, etc. and of himself as a main axis, on the art ideas of Gauguin, Gogh, Matisse, and Cezanne whose works were the typical ones participated and exhibited in those 1st and 2nd exhibitions.

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The Study on Consumption of Health Supplements and Herbal Medicines by Elementary School Students in Gyeonggi-do (수도권 지역 초등학생의 건강기능식품 및 한약 복용 실태에 대한 연구)

  • Kim, Mi-Ki;Jung, Ji-Ho;Shin, Kwon-Sung;Lee, John Dong-Yeop;Lee, Hai-Ja;Park, Eun-Jung
    • The Journal of Pediatrics of Korean Medicine
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    • v.24 no.2
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    • pp.40-48
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    • 2010
  • Objectives The purpose of this study is to get the basic information about the actual amount of consumption of the Health supplements and Herbal Medicines. Also, we investigated the consumption differences according to the regions. Methods 500 questionnaires were handed out to parents of elementary students in O O, Gyeonggi-do province, and 331 questionnaires were collected and evaluated for this study. Results Among the 331 students, 58.4% were female, and 41.6% were male. The percentages of the subjects consuming health supplements and herbal medicines were 67.4% and 59.2% respectively. The maximum period of taking the health supplements were from 1 month to 6 month (49.5%), and the maximum period of taking the herbal medicine was within one month (55.6%). The total cost of the health supplements was less than 100,000won (43.7%), which was the most common while herbal medicine cost was between 100,000won and 200,000won (40.6%). The most common age of consuming the health supplements and herbal medicine for the first time was six to ten years old (47.3%); the case of herbal medicine was one to six years old (64.0%). Most of people purchased health supplements from pharmacy (48.0%), and purchased the herbal medicine from the oriental medical clinic (61.8%). Among those people who purchased health supplements, they bought nutritional supplements (82.8%), red ginseng or ginseng products (43.4%), plum extract products (10.9%), and chlorella products (6.8%). The reason for consuming health supplements was to be healthier even though there is no ongoing illness (47.1%), which was the most common reason. The reason for consuming herbal medicine was to cure weakness (39.3%). For the responses about effectiveness after taking medications, people thought herbal medicine seemed to be more effective compare to health supplements (72.3%, 63% respectively). Only 1.4% of the subjects consuming the health supplements showed adverse effects while herbal medicine showed 4.6%. The most common adverse effects were 'general reaction' caused by the health supplements and dermatologic problems caused by the herbal medications. Conclusions Among 331 subjects, the percentage of consuming the health supplements (67.4%) was higher than the Herbal Medicine (59.2%). The total consuming cost of the herbal medications was higher than general health supplements. Also, the maximum period of consuming the health supplements was longer than herbal medications. Therefore, it is shown that herbal medications have no price competitiveness compare to health supplements. The age of using the herbal medicine for the first time was younger than the health supplements. Even though many people can purchase both health supplements and herbal medication from pharmacies and local oriental medical clinic, it is also shown that some people thought that the health supplements should be purchased from oriental medical hospital (13.9%). The most commonly taken forms of the health supplement was nutrition-supplying products, and the second common health supplements were ginseng and red ginseng. The health supplements were commonly consumed for preventing illness and for maintaining healthy life rather than for cure diseases. On the other hand, the herbal medicine was more commonly consumed to be taller or to treat diseases. More than half of the entire people replied as 'satisfied' for their purchase. Some adverse effects and general reaction were common with the subjects consuming health supplements while dermatological adverse reaction was common with the subjects consuming herbal medications.