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      • Brain SPECT 영상의 Attenuation Correction 방법들에 대한 비교

        조진우,김창호,나수경,이귀원,Jo, Jin U,Kim, Chang Ho,Na, Soo Kyung,Lee, Gui Won 대한핵의학기술학회 2012 핵의학 기술 Vol.16 No.2

        이 연구의 목적은 Brain SPECT (Single Photon Emission Computed Tomography)의 Non-attenuation correction (AC-non) 영상에 대한 attenuation correction(AC) 방법 중 Chang's method와 CT based attenuation correction(AC-CT) 사이의 count를 비교하기 위함이다. phantom study는 증류수로 채워진 hoffman 3D phantom에 $^{99m}Tc$ 37Mbq을 투여하였고, patient study는 normal volunteer에 $^{99m}Tc$-HMPAO 750Mbq를 정맥주입하고 Siemens사의 Symbia T6로 Brain SPECT 영상을 획득하였고 뇌 정량 분석을 하였다. 각각의 방법들을 적용한 transverse image는 같은 위치에서 재구성 되었으며 각각 10, 20, 30번째 slice에서 6개의 region of interest(ROI)를 그려 AC-non 과 AC-CT 그리고 Chang's method의 count를 비교하였다. phantom study에서 AC-non, AC-CT, Chang's method의 각각 평균 count는 $4606.8{\pm}511.3$, $16794.6{\pm}2429.4$, $8752.6{\pm}896.5$이었으며 patient study에서 $5460.8{\pm}519.6$, $15320{\pm}1171.6$, $12795{\pm}1422.1$이었다. phantom study에서 AC-CT와 AC-non 사이의 비는 3.70이고 Chang's method와 AC-non 사이의 비는 1.92였으며 patient study에서는 각각 2.85, 2.38이었다. 우리는 이 연구를 통하여 AC-CT가 Chang's method보다 더 높은 AC을 해준다는 걸 알 수 있었다. 그리고 Chang's method는 patient study에서의 AC 값이 phantom study에서의 AC값보다 더 높다는 것을 알 수 있었다. brain SPECT/CT를 시행하는 경우 scatter correction을 같이 시행하고 bone에 의한 감쇠 정보를 반영할 수 있는 AC-CT가 chang's method보다 정확하다 할 수 있겠다. Purpose : The purpose of this study was to compare count between Chang's method and CT-based attenuation correction (AC-CT) among the attenuation correction (AC) methods for non-attenuation correction (AC-non) images of Brain SPECT (Single Photon Emission Computed Tomography). Materials and Methods : We injected $^{99m}Tc$ 37Mbq in a Hoffman 3D phantom filled with distilled water in the phantom study, and injected intravenously $^{99m}Tc$-HMPAO 740Mbq in a normal volunteer in the patient study, and then obtained Brain SPECT images with Symbia T6 of Siemens and conducted quantitative brain analysis. Transverse images to which each method was applied were rebuilt at the same position, and 6 regions of interest (ROI) were drawn on each of Slice No. 10, 20 and 30 and then the counts of AC-non, AC-CT and Chang's method were compared. Results : The mean counts of AC-non, AC-CT and Chang's method were $4606.8{\pm}511.3$, $16794.6{\pm}2429.4$, and $8752.6{\pm}896.5$, respectively, in the phantom study and $5460.8{\pm}519.6$, $15320{\pm}1171.6$ and $12795{\pm}1422.1$, respectively, in the patient study. In the phantom study, the ratio of AC-CT to AC-non was 3.70 and the ratio of Chang's method to AC-non was 1.92, and in the patient study, they were 2.85 and 2.38, respectively. Conclusion : From this study, we found that AC-CT makes higher AC than Chang's method. In addition, when Chang's method was used, AC in the patient study was higher than that in the phantom study. These results need to be considered also in other examinations.

      • SCOPUSKCI등재

        Ce$O_2$첨가 및 분말처리가 U$O_2$ 분말의 소결에 미치는 영향

        김형수,이영우,최창범,양명승,전풍일,Kim, Hyeong-Su,Lee, Yeong-U,Choe, Chang-Beom,Yang, Myeong-Seung,Jeon, Pung-Il 한국재료학회 1993 한국재료학회지 Vol.3 No.3

        순수 $UO_2$에 첨가량 변화 및 ball-milling 시간에 따른 (U, Ce)$O_2$ 분말의 특성과 각 조건별로 제조된 분말을 압분 및 소결하여 (U, Ce)$O_2$ 분말 특성에 따른 소결성을 비교 조사하였다. 실험 결과로 부터 ball-milling시간이 길어짐에 따라 입자들은 미세화되고, Ce$O_2$ 함량이 증가할수록 압분, 소결밀도는 저하 하였으며, $CeO_2$는 소결성을 저하시키는 산화물임을 확인하였다. 10wt%,$CeO_2$ 가 첨가된 (U, Ce)$O_2$ 분말의 경우, ball-milling 4시간 수행한 분말의 소결체가 기공의 수도 적고, 구형에 가까왔으며, 소결밀도가 가장 높았다. 이는 4시간 ball-milling한 (U, Ce)$O_2$분말이 비표면적이 크로 그의 packing ratio가 적절하였기 때문이다. We investigated the changes of (U, Ce)$O_2$ powder characteristics with $CeO_2$ contents and ball-milling time and then studied on the sintering properties with those (U, Ce)$O_2$ powder characteristics. From the results of this study, it was concluded that the longer ball-milling time of (U, Ce)$O_2$ powder was, the finer its particle size was. Green and sintered densities were decreased with $CeO_2$ contensts increase. And also $CeO_2$ was recongized deteriorating oxide on the $UO_2$ sintering. In case of the lOwt. % $CeO_2$ contents, (U, Ce)$O_2$ sintered pellet which was made of ball-milled powder for 4 hours had few pores and its pores got near to the sphere. And its sintered density had the highest. Because its powder had higher surface area and its packing ratio was appropriated much better than others.

      • Economic Threshold for Diamondback Moth (Plutella xylostella (L.) ) on Leaf Broccoli (Brassica oleracea var. botrytis italiana)

        Seon-u Choi,Ju-Rak Lim,Ju-Hee Kim,Ki-Kwan Lee,Chang-yun Hwang 한국응용곤충학회 2009 한국응용곤충학회 학술대회논문집 Vol.2009 No.05

        This study was conducted to develop the economic threshold for the diamondback moth (Plutella xylostella (L.) on Leaf Broccoli (leaf vegetable) in 2007. To investigate the relationship between initial density of diamondback moth larvae and broccoli leaf yield, experimental plots with five treatments (0, 0.5, 1.0, 2.0, 4.0 larvae per plant) as initial density were established. We inoculated larvae in chesses cloth covering to survey larvae density change. When grown to eat, leaves of broccoli were harvested by periods. 60-70% of larvae were removed whenever we picked the leaves. High levels of larvae were associated with significant reductions in leaf yield. There were 85%, 64%, 58%, and 56% yield reductions from the diamond back moth larvae density in 0, 0.5, 1,0, 1.5, 2.0 per plant, respectively 25days after larvae inoculation. The regression equation used to predict leaf yield based on the number of initial larvae density per a plant was y=1635-393x(R2=0.79***). The economic injury level of diamondback moth on leaf broccoli was 2-3 larvae per 10 plants for a damage level of 5%. The economic thresholds was 1-2 larvae per 10 plants. Thus, the diamond back moth management should be initiated 1-2 larvae occurrence per plant.

      • 설진 시스템 특허동향 분석

        정창진 ( Chang Jin Jung ),이유정 ( Yu Jung Lee ),김재욱 ( Jaeuk U. Kim ),김근호 ( Keun Ho Kim ) 대한한의진단학회 2013 大韓韓醫診斷學會誌 Vol.17 No.2

        Objectives Tongue diagnosis is an important diagnostic method in traditional Eastern medicine, and it has a high potential to be used in the future healthcare because of easy, quick, and non-contact measuring features. Recently, research and development efforts on computerized tongue diagnosis systems (CTDS) have been active that led to the technical advancements in the field of photographing techniques, image extraction and classification algorithms. In this study, we analyzed the trends in the CTDS patents. Using the WIPS search engine (www.wipsglobal.com), quantitative and qualitative patent analyses were performed through Korea, China, Japan, U.S.A and Europe. Methods For a systematic search and data analysis, we defined patent categories based on the application area and technical details. By applying thus-obtained categorical key words, we obtained 360 relevant patents on photographing techniques, image extraction and classification algorithms for the purpose of diagnosis or security. Results As a result, companies related to image acquisition, medical imaging and mobile devices and research groups of universities in East Asia were major patent applicants. In all the five countries, the number of patents have been increasing since 1980. In particular, technology related to color correction and image segmentation were most actively patented categories, and expected to continue a high application rate.

      • SCOPUSKCI등재

        HaCaT 세포주에서 Epigallocatechin-3-Gallate (EGCG)가 자외선 및 LPS에 의한 iNOS mRNA 발현 및 NO 생성에 미치는 영향

        탁우정 ( Tag U Jeong ),이창균 ( Lee Chang Gyun ),서성준 ( Seo Seong Jun ),김명남 ( Kim Myeong Nam ),노병인 ( No Byeong In ),홍창권 ( Hong Chang Gwon ) 대한피부과학회 2004 대한피부과학회지 Vol.42 No.1

        N/A Background: Nitric oxide (NO) plays an important role in inflammation and multiple stages of carcinogenesis. Green tea (Camellia sinensis polyphenols are potent antiinflammatory agents and have been shown to inhibit NO production in tumor cell lines. In the present study, we examined the effect of epigallocatechinp-3-gallate (EGCG), a generation of NO in HaCaT cells. Methods: HaCaT cells were treated with 10μM EGCG and 100μM NAC for 1 hour. 1 hour later, they were irradiated with 50mJ/cm^2 UVB and treated with 200 u㎍/ml LPS for 12 hours, respectively. The iNOS mRNA was determined by reverse transcription-polymerase chain reaction (RT-PCR) and NO production was assessed by spectrophotometric method based on Griess reaction. Nuclear factor κB (NF-κB) binding activity was determined by electophoretic mobility shift assay (EMSA). Results: The results were as follows 1. EGCG inhibited UVB and LPS induced expression of inducible nitric oxide synthase. 2. HaCaT cells cotreated with EGCG produced significantly less iNOS mRNA and NO compared with HaCaT cells stimulated with UVB irradiation of LPS. 3. The inhibition of iNOS mRNA and NO production correlated with the suppression of expression of NF-κB dependent gene iNOS. 4. EGCG inhibited the activation and translocation of NF-κB to the nucleus Conclusion: inhibited the activation and translocation of NF-κB to the nucleus in HaCaT cells by interfering with the activation of NF-κB through a novel mechanism. Our results further suggest that EGCG may be therapeutically effective in UVB and cytokine induced cutaneous inflammation. (Korean J Dermatol 2004;42(1):37~46)

      • Hepatitis B Reactivation among Chronic Hepatitis C Patients Treated with Direct Acting Antivirals

        ( Hee Yeon Kim ),( Chang Wook Kim ),( Jin Ah Kim ),( Mi Ju Cheon ),( Chan Ran You ),( Sang Wook Choi ),( Se Hyun Cho ),( Joon-Yeol Han ),( Do Seon Song ),( U Im Chang ),( Jin Mo Yang ),( Sung Won Lee 대한간학회 2017 춘·추계 학술대회 (KASL) Vol.2017 No.1

        Aims: This study aimed to investigate hepatitis B virus (HBV) reactivation among hepatitis C virus (HCV) infected patients treated with oral direct acting antiviral (DAA) therapy in areas endemic for HBV in Korea. Methods: A total of 821 HCV-infected patients receiving oral DAA therapy from March 2015 to November 2016 were evaluated. Serum HBV DNA and HCV RNA was regularly assessed during and after DAA treatment in patients with HBV-HCV coinfection. HBV virological reactivation was defined as a >1 log increase in HBV DNA from baseline or a reappearance of HBV DNA for those with baseline undetectable HBV DNA. Clinical reactivation was defined as a serum alanine aminotransferase level ≥3-fold over the upper limit of normal or > 100 U/L. Results: Prior to DAA therapy 95.8% (787/821) had HBsAg testing and 1.7% (13/787) were positive. HBV virological reactivation was found in 7 (53.8%) of the 13 patients. HBV-related clinical reactivation was not observed in our cohort. Conclusions: For HBV-HCV co-infected patients, the risk of HBV virological reactivation was present after oral DAA treatment for HCV infection. Monitoring the HBV DNA level during oral DAA therapy for HCV infection is warranted.

      • SCIESCOPUSKCI등재

        Near-Normalized Gene Expression Profiles in Bladder With Detrusor Overactivity in Rats With Bladder Outlet Obstruction After Deobstruction

        Lee, Tack,Lim, U-Sung,Kang, Dong Hyuk,Jung, Hae-Do,Kim, Hyunzu,Choi, Bo-Hwa,Kang, Ju-Hee,Yoon, Sang-Min,Park, Chang-Shin Korean Continence Society 2017 International Neurourology Journal Vol.21 No.4

        <P><B>Purpose</B></P><P>The pathophysiological role of detrusor overactivity (DO) in the bladder, which is commonly observed in various bladder diseases, is not well understood. DO appears in bladder outlet obstruction (BOO), and may continue even after subsequent deobstruction. DO therefore provides an excellent opportunity to observe molecular biological changes.</P><P><B>Methods</B></P><P>In this study, to understand the molecular effects of persistent DO after BOO induction and deobstruction, we performed awake cystometry on female Sprague-Dawley rats divided into 4 groups: a sham group, a BOO group, a deobstructed group with DO after BOO (DDO), and a deobstructed group without DO after BOO (non-DDO). Total RNA was extracted from the bladder samples, and gene expression profiles were compared between the sham and model groups.</P><P><B>Results</B></P><P>DO was observed in 5 of the 6 rats (83%) in the BOO group, and in 6 of the 13 rats (46%) in the deobstructed group. The non-DDO group showed a significantly greater residual volume than the DDO group. Through a clustering analysis of gene expression profiles, we identified 7,532 common upregulated and downregulated genes, the expression of which changed by more than 2 fold. In the BOO group, 898 upregulated and 2,911 downregulated genes were identified. The non-DDO group showed 3,472 upregulated and 4,025 downregulated genes, whereas in the DDO group, only 145 and 72 genes were upregulated and downregulated, respectively.</P><P><B>Conclusions</B></P><P>Abnormal function and gene expression profiles in bladders after BOO were normalized in the BOO rats with DO after deobstruction, whereas in those without DO, abnormal function persisted and the gene expression profile became more abnormal. DO may play a protective role against the stress to the bladder induced by BOO and deobstruction as a form of adaptive neuroplasticity.</P>

      • Effect of irradiation on the parameters that influence quality characteristics of raw beef round eye

        Feng, Xi,Jo, Cheorun,Nam, Ki Chang,Ahn, Dong U. Elsevier 2018 Innovative food science & emerging technologies Vol.45 No.-

        <P><B>Abstract</B></P> <P>The objective of this study was to elucidate the relationships among lipid/protein oxidation, color changes, off-taste and off-odor in irradiated raw beef round eye. Raw beef round eye was prepared and irradiated at 0, 1.5, 3.0 and 4.5kGy using a linear accelerator. Significant increases in lipid oxidation and protein oxidation were found in irradiated raw beef round eye, while significant decreases were observed in the color values (L*-, a*-, and b*-value). The degradation of nucleotides can contribute to the taste changes (increase in sourness and decrease in umami taste) in the irradiated raw beef round eye, which was further confirmed by the electronic tongue data. The sulfur volatiles (e.g.: dimethyl disulfide) from the sulfur-containing amino acids increased significantly after irradiation, indicating these are closely related to the off-odor of irradiated beef round eye.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Lipid/protein oxidation was accelerated in raw beef round eye by irradiation. </LI> <LI> After irradiation, color values (L*-, a*-, and b*-value) in raw beef round eye decreased. </LI> <LI> The nucleotides degradation by irradiation can contribute to the taste changes. </LI> <LI> Irradiation off-odor was correlated to dimethyl disulfide and 2-butanone productions. </LI> </UL> </P>

      • HBV : Retrospective Observational Study to Evaluate the Efficacy of Entecavir in Patients with Chronic Hepatitis B Virus Infection in Korea: Real-Life Clinical Outcomes

        ( Chung-Hwa Park ),( Sung Won Lee ),( Hee Yeon Kim ),( Do Seon Song ),( Hyun Jin Kim ),( Myeong Jun Song ),( Jung Hyun Kwon ),( Chan Ran You ),( Jeong Won Jang ),( U Im Chang ),( Chang Wook Kim ),( So 대한간학회 2013 춘·추계 학술대회 (KASL) Vol.2013 No.1

        Background: Entecavir, has demonstrated superior histologic, virologic, and biochemical benefit. Still, its long-term clinical outcome is not well established in the Korean clinical area, and also in subjects who stopped the treatment. Methods: This is a multicenter, retrospective cohort observational study to evaluate the efficacy of Entecavir long-term treatment in CHB patients at hospitals affiliated to the Catholic University of Korea through analysis of the electronic medical record data from January 1, 2006 to December 31, 2012. Results: Among 2,440 patients prescribed with entecavir 0.5mg qd, 1,337 patients were treatment naive. Excluding 533 patients with concomitant conditions, 578 patients were ontreatment and 226 patient stopped entecavir during the study period. At 6mo, year 1, 2, 3, 4 and 5, cumulative incidences of complete virologic response (HBV-DNA < 300 copies/mL) was 379, 530, 573, 577, 579 and 579, respectively. HBsAg loss rate was 9.86%, and among 440 HBeAg-positive patients, HBeAg loss rate and HBeAg loss with HBeAb positivity rate was 20.00% and 17.43%, respectively, at year 1. During the study period, 226 patients stopped entecavir, and at year 1 after cessation, cumulative virologic relapse (HBV-DNA>10^4 copies/ mL) and biochemical relapse (ALT>40 U/L) were 22.57% and 20.35%, respectively with mean days of 191.06±67.0 and 188.39±90.15, respectively. Prognotsic factor for earlier CVR was HBV-DNA<10^7cpm at initiating entecavir (P<0.005). Among those who stopped the medication, prognostic factor for virological relapse was HBV-DNA ≥10^7cpm at initiating entecavir (P=0.022). Conclusions: Long term use of entecavir may achieve CVR in most patients, and patients with higher viral load should be considered of indefinite duration of treatment regardless of age, sex, biochemical markers or HBeAg status.

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