• Title/Summary/Keyword: bio-medical

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Gadoteridol's Signal Change according to TR, TE Parameters in T1 Image (T1영상에서 TR, TE 매개변수에 따른 Gadoteridol의 신호강도 변화)

  • Jeong, Hyun Keun;Jeong, Hyun Do;Nam, Ki Chang;Kim, Ho Chul
    • Journal of the Institute of Electronics and Information Engineers
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    • v.52 no.9
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    • pp.117-124
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    • 2015
  • In this paper, we introduce how to control TR, TE physical MR parameters for managing $H_1$ spin's SI(Signal Intensity) which is combined with gadolinium following administration MR agent in T1 effect for diagnostic usefulness. we used MRI phantom made with 0.5 mol Gadoteridol. This phantom was scanned by FSE sequence with different TR, TE parameters. In this study, to make T1 effect, TR was 200, 250, 300, 350, 400, 450, 500, 550, 600 msec. In addition to, TE was 6.2, 12.4, 18.6, 21.6 msec. The results were as follows ; Each RSP(Reaction Starting Point) was 100, 50, 40, 30 mmol in TE 6.2, 12.4, 18.6, 21.6 msec being irrelevant to TR. In MPSI(Max Peak Signal Intensity), 4 mmol was showed in TR 200 msec while peak signal was decreased to low concentration mol in TR 250-600 msec. In terms of RA(Reaction Area), the highest SI was TE 6.2 msec in TR 200-600msec. According to the study, we are able to recognize it is possible to control enhance rates by managing TR and TE of MR parameters; moreover, we expect that enhanced T1 image in MR clinical field can be performed in a practical way with this quantitative data.

Development of Lead Free Shielding Material for Diagnostic Radiation Beams (의료영상용 방사선방호를 위한 무납차폐체 개발)

  • Choi, Tae-Jin;Oh, Young-Kee;Kim, Jin-Hee;Kim, Ok-Bae
    • Progress in Medical Physics
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    • v.21 no.2
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    • pp.232-237
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    • 2010
  • The shielding materials designed for replacement of lead equivalent materials for lighter apron than that of lead in diagnostic photon beams. The absorption characteristics of elements were applied to investigate the lead free material for design the shielding materials through the 50 kVp to 110 kVp x-ray energy in interval of 20 kVp respectively. The idea focused to the effect of K-edge absorption of variable elements excluding the lead material for weight reduction. The designed shielding materials composited of Tin 34.1%, Antimon 33.8% and Iodine 26.8% and Polyisoprene 5.3% gram weight account for 84 percent of weight of lead equivalent of 0.5 mm thickness. The size of lead-free shielder was $200{\times}200{\times}1.5\;mm^3$ and $3.2\;g/cm^3$ of density which is equivalent to 0.42 mm of Pb. The lead equivalent of 0.5 mm thickness generally used for shielding apron of diagnostic X rays which is transmitted 0.1% for 50 kVp, 0.9% for 70 kVp and 3.2% for 90 kVp and 4.8% for 110 kVp in experimental measurements. The experiment of transmittance for lead-free shielder has showed 0.3% for 50 kVp, 0.6% for 70 kVp, 2.0% for 90 kVp and 4.2% for 110 kVp within ${\pm}0.1%$. respectively. Using the attenuation coefficient of experiments for 0.5 mm Pb equivalent of lead-free materials showed 0.1%. 0.3%, 1.0% and 2.4%, respectively. Furthermore, the transmittance of lead-free shielder for scatter rays has showed the 2.4% in operation energy of 50 kVp and 5.9% in energy of 110 kVp against 2.4% and 5.1% for standard lead thickness within ${\pm}0.2%$ discrepancy, respectively. In this experiment shows the designed lead-free shielder is very effective for reduction the apron weight in diagnostic radiation fields.

Evaluation of Image Quality for Various Electronic Portal Imaging Devices in Radiation Therapy (방사선치료의 다양한 EPID 영상 질평가)

  • Son, Soon-Yong;Choi, Kwan-Woo;Kim, Jung-Min;Jeong, Hoi-Woun;Kwon, Kyung-Tae;Cho, Jeong-Hee;Lee, Jea-Hee;Jung, Jae-Yong;Kim, Ki-Won;Lee, Young-Ah;Son, Jin-Hyun;Min, Jung-Whan
    • Journal of radiological science and technology
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    • v.38 no.4
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    • pp.451-461
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    • 2015
  • In megavoltage (MV) radiotherapy, delivering the dose to the target volume is important while protecting the surrounding normal tissue. The purpose of this study was to evaluate the modulation transfer function (MTF), the noise power spectrum (NPS), and the detective quantum efficiency (DQE) using an edge block in megavoltage X-ray imaging (MVI). We used an edge block, which consists of tungsten with dimensions of 19 (thickness) ${\times}$ 10 (length) ${\times}$ 1 (width) $cm^3$ and measured the pre-sampling MTF at 6 MV energy. Various radiation therapy (RT) devices such as TrueBeam$^{TM}$ (Varian), BEAMVIEW$^{PLUS}$ (Siemens), iViewGT (Elekta) and Clinac$^{(R)}$iX (Varian) were used. As for MTF results, TrueBeam$^{TM}$(Varian) flattening filter free(FFF) showed the highest values of $0.46mm^{-1}$ and $1.40mm^{-1}$ for MTF 0.5 and 0.1. In NPS, iViewGT (Elekta) showed the lowest noise distribution. In DQE, iViewGT (Elekta) showed the best efficiency at a peak DQE and $1mm^{-1}DQE$ of 0.0026 and 0.00014, respectively. This study could be used not only for traditional QA imaging but also for quantitative MTF, NPS, and DQE measurement for development of an electronic portal imaging device (EPID).

Analysis of Factors Influencing the Integrated Bolus Peak Timing in Contrast-Enhanced Brain Computed Tomographic Angiography (Computed Tomographic Angiography (CTA)의 검사 시 조영제 집적 정점시간에 영향을 미치는 특성 인자를 분석)

  • Son, Soon-Yong;Choi, Kwan-Woo;Jeong, Hoi-Woun;Jang, Seo-Goo;Jung, Jae-Yong;Yun, Jung-Soo;Kim, Ki-Won;Lee, Young-Ah;Son, Jin-Hyun;Min, Jung-Whan
    • Journal of radiological science and technology
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    • v.39 no.1
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    • pp.59-69
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    • 2016
  • The objective of this study was to analyze the factors influencing integrated bolus peak timing in contrast-enhanced computed tomographic angiography (CTA) and to determine a method of calculating personal peak time. The optimal time was calculated by performing multiple linear regression analysis, after finding the influence factors through correlation analysis between integrated peak time of contrast medium and personal measured value by monitoring CTA scans. The radiation exposure dose in CTA was $716.53mGy{\cdot}cm$ and the radiation exposure dose in monitoring scan was 15.52 mGy (2 - 34 mGy). The results were statistically significant (p < .01). Regression analysis revealed, a -0.160 times decrease with a one-step increase in heart rate in male, and -0.004, -0.174, and 0.006 times decrease with one-step in DBP, heart rate, and blood sugar, respectively, in female. In a consistency test of peak time by calculating measured peak time and peak time by using the regression equation, the consistency was determined to be very high for male and female. This study could prevent unnecessary dose exposure by encouraging in clinic calculation of personal integrated peak time of contrast medium prior to examination.

Biological Activity of Ethanol Extracts from Amelanchier asiatica Fruits (채진목(Amelanchier asiatica) 열매 에탄올 추출물의 생리활성)

  • Chae, Jung-Woo;Kim, Jin-Sung;Jo, Bun-Sung;Kang, Sun-Ae;Park, Hye-Jin;Joo, Sung-Hyun;Chun, Sung-Sook;Cho, Young-Je
    • Journal of Applied Biological Chemistry
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    • v.54 no.4
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    • pp.238-243
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    • 2011
  • Amelanchier asiatica fruits have been used as a traditional medical food. This research was investigated to assess angiotensin converting enzyme, xanthine oxidase (XOase) and elastase inhibitory activity and antioxidant activities. The content of total phenolic compounds in A. asiatica fruits extracts was 17.6mg/mL. In extracts, the electron donating ability by 1,1-diphenyl-2-picrylhydrazyl free radical scavenging test of A. asiatica fruits extracts was 90.18% at $200{\mu}g/mL$. The 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid radical decolorization of A. asiatica fruits extracts was 98.81% at $200{\mu}g/mL$. The inhibition rate of the antioxidant protection factor was 1.03, and thiobarbituric acid reactive substance was 73.27% at $200{\mu}g/mL$. The XOase inhibition activity of A. asiatica fruits extracts of showed to be 13.19% at $200{\mu}g/mL$. The angiotensin converting enzyme activity was significantly inhibited by A. asiatica fruits extracts as 82.52% inhibitory rate at $200{\mu}g/mL$. Elastase inhibitory activity in the A. asiatica fruits extracts (41.48% at $200{\mu}g/mL$) was higher than vitamin C (12.8% at $200{\mu}g/mL$). These results suggests that A. asiatica fruits extracts have the greatest property as a functional food and functional cosmetic source.

Removable implant-supported partial denture using milled bar with Locator® attachments in a cleft lip & palate patient: A clinical report (구순구개열 환자에서 Locator® 유지장치가 장착된 milled titanium bar를 이용한 가철성 임플란트 피개 국소의치의 보철수복증례)

  • Yang, Sang-Hyun;Kim, Kyoung-A;Kim, Ja-Yeong;Seo, Jae-Min
    • The Journal of Korean Academy of Prosthodontics
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    • v.53 no.3
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    • pp.207-214
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    • 2015
  • Due to the limitations of conventional removable partial denture prostheses to treat a cleft lip & palate patient who shows scar tissue on upper lip, excessive absorption of the maxillary residual alveolar ridge, and class III malocclusion with narrow palate and undergrowth of the maxilla, 4 implants were placed on the maxillary edentulous region and a maxillary removable implant-supported partial denture was planned using a CAD/CAM milled titanium bar. Unlike metal or gold casting technique which has shrinkage after the molding, CAD/CAM milled titanium bar is highly-precise, economical and lightweight. In practice, however, it is very hard to obtain accurate friction-fit from the milled bar and reduction in retention can occur due to repetitive insertion and removal of the denture. Various auxiliary retention systems (e.g. $ERA^{(R)}$, $CEKA^{(R)}$, magnetics, $Locator^{(R)}$ attachment), in order to deal with these problems, can be used to obtain additional retention, cost-effectiveness and ease of replacement. Out of diverse auxiliary attachments, $Locator^{(R)}$ has characteristics that are dual retentive, minimal in vertical height and convenient of attachment replacement. Drill and tapping method is simple and the replacement of the metal female part of $Locator^{(R)}$ attachment is convenient. In this case, the $Locator^{(R)}$ attachment is connected to the milled titanium bar fabricated by CAD/CAM, using the drill and tapping technique. Afterward, screw holes were formed and 3 $Locator^{(R)}$ attachments were secured with 20 Ncm holding force for additional retention. Following this procedure, satisfactory results were obtained in terms of aesthetic facial form, masticatory function and denture retention, and I hereby report this case.

Increased Growth by LED and Accumulation of Functional Materials by Florescence Lamps in a Hydroponics Culture System for Angelica gigas (당귀의 수경재배에서 LED 광원에 의한 생장 증가와 형광등에 의한 기능성물질 축적)

  • Lee, Gong-In;Kim, Hong-Ju;Kim, Sung-Jin;Lee, Jong-Won;Park, Jong-Seok
    • Journal of Bio-Environment Control
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    • v.25 no.1
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    • pp.42-48
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    • 2016
  • Angelica gigas, belonging family Apiaceae, is a perennial and famous medical plant growing in Korea, Japan, and China. The aims of this study was to analyze the growth and accumulated Decursin and its precursor Decursinol angelate of A.gigas grown under fluorescent lamp and LED. A. gigas 'Manchu' were sowed and managed for seedlings stage in a glass house for 4 weeks. One hundred twenty seedlings with 3 true leafs were transplanted at an ebb & flow system with fluorescent lamp and LED [red: peak wavelength 660nm, blue: peak wavelength 455 nm, white = 3:2:4 ratio] irradiated at $180{\pm}7{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ at the top of plant canopy for 5 weeks. The number of leaves increased by 13.5% in the LED treatment, though it is not statistically significant. Leaf length/width ratio of A. gigas grown under the fluorescent lamps was 24% bigger than the LED treatment and also the stem was 13% larger. Maximum root length was similar to both groups. Fresh weight and dry weight of shoots grown under the LED increased by 50% and 42% and the both weights of roots increased by 125% and 45%, respectively. The contents of Decursin and Decursinol angelate grown under the florescent lamps were larger than LED by 188% and 27% in shoot and 78% and 8% in root. The contents of Decursin and Decursinol angelate per plant grown under LED and florescent lamps were 132mg and 122mg. In conclusion, functional materials in A. gigas were increased by florescent light and its growth was promoted by LEDs light.

Influence of Short-term Application of Abscisic Acid in Nutrient Solution on Growth and Drought Tolerance of Tomato Seedlings (토마토 육묘과정에서 단기간 ABA처리가 묘소질과 건조내성에 미치는 영향)

  • Kim, Il-Seop;Vu, Ngoc-Thang;Vo, Hoang-Tung;Choi, Ki-Young;Kim, Young Shik
    • Journal of Bio-Environment Control
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    • v.24 no.1
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    • pp.13-20
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    • 2015
  • This study was conducted to evaluate influence of short-term application of abscisic acid (ABA) in nutrient solution on growth and drought tolerance of tomato seedlings. The treatments included four ABA concentrations (0.5, 1, 2, $3mg{\cdot}L^{-1}$) and control (non-treatment) were applied to the nutrient solution in a hydroponic system. On the $5^{th}$ and $10^{th}$ day after growing in the nutrient solution containing ABA, seedlings were transferred to -5 bars of PEG-8000 in a growth chamber to induce water stress. Except for stem diameter and fresh and dry weight of root, there were no statistical differences in other growth parameters among control, 0.5 and $1mg{\cdot}L^{-1}$ of ABA treatments. Seedlings growths were strongly inhibited in nutrient solution containing 2 and $3mg{\cdot}L^{-1}$ of ABA. The root growth such as fresh and dry weigh of root, total root surface area, and average root diameter was slightly enhanced in $1mg{\cdot}L^{-1}$ of ABA treatment. The elevation of ABA concentrations in nutrient solution resulted in the decrease in transpiration rate and increase in stomatal diffusive resistance and leaf temperature of tomato seedlings. The initiations of seedling wilting after treating in -5 bars of PEG were delayed from 10 hrs in control to 30 hrs in ABA applied treatments. Additionally, the high percentages of recovered seedlings were observed in 0.5 and $1mg{\cdot}L^{-1}$ of ABA treatments after re-irrigation. Therefore, short-term application of $1mg{\cdot}L^{-1}$ of ABA in the nutrient solution stimulated the root growth and drought tolerance of tomato seedlings by delaying the start time of wilting point and enhancing the recovery after re-irrigation.

Survey of Unexpected Antibodies Identified at a General Hospital in Jeju (제주지역 일개 종합병원에서 동정된 비예기항체의 실태조사)

  • Chong, Moosang;Lee, Kyu-taeg;Cho, Young-Kuk
    • Korean Journal of Clinical Laboratory Science
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    • v.49 no.4
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    • pp.390-394
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    • 2017
  • Unexpected antibody screening and identification tests are highly important in the prevention of hemolytic transfusion reactions. Therefore, it is highly recommended to perform unexpected antibody screening test in all transfusion candidates. Here, the frequency and distribution of unexpected antibodies identified in Jeju for the past 3 years were evaluated. Between Jan 2014 and Dec 2016, unexpected antibody screening test was performed for 10,360 sera of transfusion candidates in Jeju general hospital using a column agglutination method with the Ortho BioVue system (Ortho-clinical Diagnostics, Raritan, NJ, USA). Eighty-seven (0.84%) of 10,360 cases that underwent unexpected antibiotics screening showed positive results. Among them, unexpected antibodies were identified in 41 cases (0.40%). Unidentified antibodies were detected in 8 cases (19.51%) and autoantibodies were detected in 3 cases (7.32%). The anti-E antibody included in warm antibodies were detected most frequently in 8 cases (19.51%); 6 cases (14.63%) of anti-E + anti-c antibody and 3 cases (7.32%) of $anti-Le^a+anti-Le^b$. $Anti-Le^a$ and $anti-Le^b$ antibodies were detected in 2 cases (4.88%), respectively. The anti-D, $anti-Di^a$, $anti-Fy^b$, $anti-Jk^a$, $anti-Jk^b$, anti-M and anti-P1 were detected in 1 case (2.44%). Complex antibodies were detected in 1 case (2.44%) in anti-C+anti-D and anti-E+anti-c+$anti-Jk^b$, respectively. In this study, we analyzed the frequency and distribution of unexpected antibodies in one general hospital for the past 3 years. However, there has been a general increase in multicultural families and foreign workers in Jeju, and it would be a meaningful study to compare the frequency and distribution of unexpected antibodies.

Evaluation of the Automated Immunohematology Analyzer DAYMATE M (혈액은행 자동화 검사장비 DAYMATE M의 수행능 평가)

  • Yoo, Jaeeun;Yu, Hain;Choi, Hyunyu;Lee, Gyoo Whung;Song, Young-Sun;Lee, Seungok;Jekarl, Dong Wook;Kim, Yonggoo
    • Laboratory Medicine Online
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    • v.7 no.4
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    • pp.163-169
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    • 2017
  • Background: An automated immunohematology analyzer, DAYMATE M (DAY Medical, Switzerland), has been recently developed. The potential of this analyzer to improve test results has been evaluated. Methods: A total of 300 blood samples from Seoul St. Mary's hospital and Incheon St. Mary's hospital were tested for ABO and RhD typing. In addition, 336 antibody screening test (AST) samples and 82 patients treated with hematopoietic stem cell transplantation (HSCT) were included. AST results by DAYMATE M were compared with those obtained by a manual method using DS-Screening II (Bio-Rad Laboratories, Switzerland) and red blood cells from Selectogen (Ortho-Clinical diagnostics Inc., USA). Results: Of the 300 patients enrolled, 87, 73, 79, and 61 had type A, B, O, and AB blood, respectively. The concordance rate was 99.9% for cell typing and 97.0% for serum typing. One discordant case was classified as type B instead of AB, and six discordant serum-typing cases were type A, but classified as type AB. Among the 336 AST samples, the concordance rate was 93.2%. From 136 positive cases, six were discordant. Within the 82 HSCT-treated patients, the concordance rate for ABO blood typing was 92.2%. Among the six discordant cases, DAYMATE M typed four cases as donor type where the standard method typed them as the recipient blood type. Conclusions: The DAYMATE M automated immunohematology analyzer performs reliably for ABO and RhD typing, as well as for ASTs and on samples from patients treated with HSCT.