• Title/Summary/Keyword: ${\tau}_m$

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Effect of KwyBiChongMung-Tang Hot Water Extract & Ultra-fine Powder on the Alzheimer's Disease Model (귀비총명탕 열수추출물과 초미세분말제형이 Alzheimer's Disease 병태 모델에 미치는 영향)

  • Lee, Seung-Hee;Lee, Sang-Ryong;Jung, In-Chul
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.21 no.4
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    • pp.921-933
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    • 2007
  • This experiment was designed to investigate the effects of the KBCMT hot water extract & ultra-fine powder on Alzheimer's Disease Model Induced by ${\beta}A$. The effects of the KBCMT hot water extract on expression of $IL-1{\beta}$, IL-6, $TNF-{\alpha}$, NOS-II, COX-2 mRNA and production of $IL-1{\beta}$, IL-6, $TNF-{\alpha}$, NO in BV2 microglial cell line treated by lipopolysacchaide(LPS). The effects of the KBCMT hot water extract & ultra-fine powder on (1) the behavior (2) expression of $IL-1{\beta}$, $TNF-{\alpha}$, MDA, CD68 and CD11b; (3) AChE in serum (4) the infarction area of the hippocampus, and brain tissue injury in Alzheimer's diseased mice induced with ${\beta}A$ were investigated. The KBCMT hot water extract suppressed the expression of $IL-1{\beta}$, IL-6 and $TNF-{\alpha}$ mRNA in BV2 microglia cell line treated with LPS. The KBCMT hot water extract suppressed the production of $IL-1{\beta}$, IL-6, $TNF-{\alpha}$, NO in BV2 microglial cell line treated with LPS. The KBCMT hot water extract & ultra-fine powder a significant inhibitory effect on the memory deficit was shown for the mice with Alzheimer's disease induced by ${\beta}A$ in the Morris water maze experiment, which measured stop-through latency and distance movemet-through latency The KBCMT ultra-fine powder suppressed the expression of TNF-a protein significantly in the microglial cell of mice with Alzheimer's disease induced by ${\beta}A$. The KBCMT hot water extract & ultra-fine powder reduced the MDA and suppressed the over-expression of CD68, CD11b in the mice with Alzheimer's disease induced by ${\beta}A$. The KBCMT hot water extract & ultra-fine powder decreased AChE significantly in the serum of the mice with Alzheimer's disease induced by ${\beta}A$. The KBCMT hot water extract & ultra-fine powder reduced infarction area of hippocampus, and controlled the injury of brain tissue in the mice with Alzheimer's disease induced by ${\beta}A$. The KBCMT hot water extract & ultra-fine powder reduced the tau protein, GFAP, and presenilin1, 2 of hippocampus in the mice with Alzheimer's disease induced by ${\beta}A$. These results suggest that the KBCMT hot water extract & ultra-fine powder may be effective for the prevention and treatment of Alzheimer's disease. Investigation into the clinical use of the KBCMT hot water extract & ultra-fine powder for Alzheimer's disease is suggested for future research.

Effects of Sesim-tang Hot Water Extract & Ultra-fine Powder on the Alzheimer's Disease Model (세심탕(洗心湯) 열수추출물, 초미세분말제형이 Alzheimer's Disease 병태 모델에 미치는 영향)

  • Kim, Hyun-Soo;Lee, Sang-Yong;Jung, In-Chul
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.21 no.3
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    • pp.688-699
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    • 2007
  • This experiment was designed to investigate the effect of the SST hot water extract & ultra-fine Powder on Alzheimer's Disease Model Induced by ${\beta}$A. The effects of the SST hot water extract on expression of IL-1${\beta}$, IL-6, TNF-${\alpha}$, NOS-II, COX-2 mRNA and production of IL-l${\beta}$, IL-6, TNF-${\alpha}$, NO in BV2 microglial cell line treated by lipopolysacchaide(LPS). The effects of the SST hot water extract & ultra-fine powder on (1) the behavior (2) expression of IL-1${\beta}$, TNF-${\alpha}$, MDA, (3) Glucose, AChE in serum (4) the infarction area of the hippocampus, and brain tissue injury in Alzheimer's diseased mice induced with ${\beta}$A were investigated. The SST hot water extract suppressed the expression of IL-1${\beta}$, IL-6 and TNF-a mRNA ${\alpha}$in BV2 microglia cell line treated with LPS. The SST hot water extract suppressed the production of IL-1${\beta}$, IL-6, TNF-${\alpha}$, NO in BV2 microglial cell line treated with LPS. The SST hot water extract & ultra-fine powder a significant inhibitory effect on the memory deficit was shown for the mice with Alzheimer's disease induced by ${\beta}$A in the Morris water maze experiment, which measured stop-through latency. The SST ultra-fine powder suppressed the expression of TNF-a protein significantly in the microglial cell of mice with Alzheimer's disease induced by ${\beta}$A. The SST hot water extract & ultra-fine powder reduced the MDA and suppressed the over-expression of CD68, CD11b in the mice with Alzheimer's disease induced by ${\beta}$A. The SST hot water extract & ultra-fine powder decreased AChE significantly in the serum of the mice with Alzheimer's disease induced by ${\beta}$A. The SST hot water extract & ultra-fine powder reduced infarction area of hippocampus, and controlled the injury of brain tissue in the mice with Alzheimer's disease induced by ${\beta}$A. The SST hot water extract & ultra-fine powder reduced the tau protein, GFAP, and presenilin1, 2 of hippocampus in the mice with Alzheimer's disease induced by ${\beta}$A. These results suggest that the SST hot water extract & ultra-fine powder may be effective for the prevention and treatment of A1zheimer's disease. Investigation into the clinical use of the SST hot water extract & ultra-fine powder for Alzheimer's disease is suggested for future research.

Assessment of Bone Metastasis using Nuclear Medicine Imaging in Breast Cancer : Comparison between PET/CT and Bone Scan (유방암 환자에서 골전이에 대한 핵의학적 평가)

  • Cho, Dae-Hyoun;Ahn, Byeong-Cheol;Kang, Sung-Min;Seo, Ji-Hyoung;Bae, Jin-Ho;Lee, Sang-Woo;Jeong, Jin-Hyang;Yoo, Jeong-Soo;Park, Ho-Young;Lee, Jae-Tae
    • Nuclear Medicine and Molecular Imaging
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    • v.41 no.1
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    • pp.30-41
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    • 2007
  • Purpose: Bone metastasis in breast cancer patients are usually assessed by conventional Tc-99m methylene diphosphonate whole-body bone scan, which has a high sensitivity but a poor specificity. However, positron emission tomography with $^{18}F-2-deoxyglucose$ (FDG-PET) can offer superior spatial resolution and improved specificity. FDG-PET/CT can offer more information to assess bone metastasis than PET alone, by giving a anatomical information of non-enhanced CT image. We attempted to evaluate the usefulness of FDG-PET/CT for detecting bone metastasis in breast cancer and to compare FDG-PET/CT results with bone scan findings. Materials and Methods: The study group comprised 157 women patients (range: $28{\sim}78$ years old, $mean{\pm}SD=49.5{\pm}8.5$) with biopsy-proven breast cancer who underwent bone scan and FDG-PET/CT within 1 week interval. The final diagnosis of bone metastasis was established by histopathological findings, radiological correlation, or clinical follow-up. Bone scan was acquired over 4 hours after administration of 740 MBq Tc-99m MDP. Bone scan image was interpreted as normal, low, intermediate or high probability for osseous metastasis. FDG PET/CT was performed after 6 hours fasting. 370 MBq F-18 FDG was administered intravenously 1 hour before imaging. PET data was obtained by 3D mode and CT data, used as transmission correction database, was acquired during shallow respiration. PET images were evaluated by visual interpretation, and quantification of FDG accumulation in bone lesion was performed by maximal SUV(SUVmax) and relative SUV(SUVrel). Results: Six patients(4.4%) showed metastatic bone lesions. Four(66.6%) of 6 patients with osseous metastasis was detected by bone scan and all 6 patients(100%) were detected by PET/CT. A total of 135 bone lesions found on either FDG-PET or bone scan were consist of 108 osseous metastatic lesion and 27 benign bone lesions. Osseous metastatic lesion had higher SUVmax and SUVrel compared to benign bone lesion($4.79{\pm}3.32$ vs $1.45{\pm}0.44$, p=0.000, $3.08{\pm}2.85$ vs $0.30{\pm}0.43$, p=0.000). Among 108 osseous metastatic lesions, 76 lesions showed as abnormal uptake on bone scan, and 76 lesions also showed as increased FDG uptake on PET/CT scan. There was good agreement between FDG uptake and abnormal bone scan finding (Kendall tau-b : 0.689, p=0.000). Lesion showed increased bone tracer uptake had higher SUVmax and SUVrel compared to lesion showed no abnormal bone scan finding ($6.03{\pm}3.12$ vs $1.09{\pm}1.49$, p=0.000, $4.76{\pm}3.31$ vs $1.29{\pm}0.92$, p=0.000). The order of frequency of osseous metastatic site was vertebra, pelvis, rib, skull, sternum, scapula, femur, clavicle, and humerus. Metastatic lesion on skull had highest SUVmax and metastatic lesion on rib had highest SUVrel. Osteosclerotic metastatic lesion had lowest SUVmax and SUVrel. Conclusion: These results suggest that FDG-PET/CT is more sensitive to detect breast cancer patients with osseous metastasis. CT scan must be reviewed cautiously skeleton with bone window, because osteosclerotic metastatic lesion did not showed abnormal FDG accumulation frequently.

음향공에 의한 LOX-RP1 고주파 음향-연소안정화에 관한 연구

  • 이길용;윤웅섭;조용호
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2000.04a
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    • pp.5-5
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    • 2000
  • 액체 추진 로켓 엔진의 고주파 연소 불안정 관련 이론은 대체로 연소기 내부의 음향 공명 모드와 분무 연소 과정의 상호 작용을 구동 메커니즘으로 전제하며 Rayleigh Criterion의 재해석에 기초하여 불안정성 평가를 위한 매개변수를 도입하고 연소 불안정성을 예측한다. 여기에는 음향장 분석 이론, 음향 불안정 이론, 연소응답 및 기화반응 이론 등이 포함된다. 본 연구에서는 LOX/RPl 추진제 조합의 액체 추진 로켓 엔진 연소기를 대상으로 다차원 순수 음향장 해석과 연소-음향장 분석을 통해 대상 엔진의 고주파 연소 불안정 특성을 예측하였다. 수동 제어 기기인 음향공 설치에 따른 연소기의 음향장 및 연소-음향장의 특성 변화를 고찰하고 위 결과를 종합하여 음향공의 연소 불안정 억제 성능 및 대상 엔진의 연소 불안정성을 평가하였다. 연소기 형상 및 음향공 설치에 따른 다차원 순수 음향장 해석은 상용코드인 ANSYS를 사용하여 수행하였다. 내부 유체는 압축성, 비점성 유체로 유체의 평균 유동은 무시하며 위치에 관계없이 균일한 물성치를 부여하였다. 정상상태 연소과정을 가정하고 평형 화학을 이용한 분석 결과로부터 연소 기체의 관련 물성치를 결정하였다. 연소기 길이 방향, 반경 방향, 원주 방향 격자점들의 음향 특성을 주파수 영역에 대해 해석하고 3차원 음향 모드 형상을 토대로 음향장을 분석하였다. 연소-음향장 해석은 음향 불안정 이론 중 n- $\tau$ 2 매개변수 기법을 사용하였다. 연료 액적의 분무 연소 과정을 1차원적으로 가정하고 정상상태의 평형 화학 계산 결과를 이용하여 엔진의 연소면을 1차원적으로 설정하였다. 상류 연소응답과 중립 안정 곡선을 토대로 대상 엔진의 연소 불안정 특성을 분석하였다.구 분석 결과 기술적 문제점으로는 배기 가스온도가 낮은데 따른 출구 부분의 Bearing, Sealing이 문제가 될 수 있다고 판단되며 배기 가스 자체에 대기 공기중에 함유되어 있던 습기가 얼어붙는(Icing화) 문제가 발생하기 때문에 배기가스의 Icing을 방지하기 위하여 압축기 끝단에서 공기를 추출하여 배기부분에 송출할 필요성이 있는 것으로 판단되었다. 출구가스의 기체 유동속도가 매우 빠르므로 (100-l10m.sec) 이를 완화하기 위한 디퓨저의 설계가 요구된다고 판단된다. 또 연소기 후방에 물을 주입하는 경우 열교환기 및 기타 부분품에 발생할 수 있는 부식 및 열교환 효율 저하도 간과할 수 없는 문제로 파악되었다. 이러한 기술적 문제가 적절히 해결되는 경우 비활성 가스 제너레이터는 민수용으로는 대형 빌딩, 산림, 유조선 등의 화재에 매우 적절히 사용되어 질 수 있을 뿐 아니라 군사적으로도 군사작전 중 및 공군 기지의 화재 그리고 지하벙커에 설치되어 있는 고급 첨단 군사 장비 등의 화재 뿐 아니라 대간첩작전 등에 효과적으로 활용될 수 있을 것으로 판단된다.가 작으며, 본 연소관에 충전된 RDX/AP계 추진제의 경우 추진제의 습기투과에 의한 추진제 물성 변화는 미미한 것으로 나타났다.의 향상으로, 음성개선에 효과적이라고 사료되었으며, 이 방법이 편측 성대마비 환자의 효과적인 음성개선의 치료방법의 하나로 응용될 수 있으리라 생각된다..7%), 혈액투석, 식도부분절제술 및 위루술·위회장문합술을 시행한 경우가 각 1례(2.9%)씩이었다. 13) 심각한 합병증은 9례(26.5%)에서 보였는데 그중 식도협착증이 6례(17.6%), 급성신부전증 1례(2.9%), 종격동기흉과 폐염이 병발한 경우와 폐염이 각 1례(2.9%)였다. 14)

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Comparison of Regional Myocardial Perfusion, Left Ventricular Volume and Ejection Fraction between 8- and 16-Frame Gated SPECT (8-단위영상과 16-단위영상으로 얻은 게이트 심근관류 스펙트에서 국소 심근관류, 좌심실 용적과 구혈률의 비교)

  • Lee, Sang-Woo;Lee, Jae-Tae;Bae, Jin-Ho;Jeong, Shin-Young;Chun, Kyung-Ah;Ha, Jeoung-Hee;Ahn, Byeong-Cheol;Lee, Kyu-Bo
    • The Korean Journal of Nuclear Medicine
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    • v.37 no.5
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    • pp.269-277
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    • 2003
  • 목적: 게이트 심근관류 스펙트는 심근의 관류와 좌심실 기능을 동시에 평가할 수 있는 유용한 방법이다. 현재, 게이트 영상 획득시 8 단위영상이 널리 사용되지만, 아직 가장 적절한 단위영상의 수에 대해서는 논의의 여지가 있다. 본 연구는 동일한 환자에서 8 단위영상과 16 단위영상으로 게이트 심근관류 스펙트를 2회 연속적으로 시행하여 국소적 심근관류, 좌심실 용적과 구혈률등을 비교하였다. 대상 및 방법: 42명(평균 연령: 55세, 남: 녀=26: 16)의 관상동맥 질환이 의심되거나 알려진 환자를 대상으로 안정시 Tc-99m MIBI를 이용한 게이트 스펙트를 8 단위영상과 16 단위영상으로 2회 연속하여 시행하였다. 좌심실의 확장기말 용적, 수축기말 용적과 구혈률을 각각 얻었으며 확장기말의 단층영상을 18 분절로 나누고 각 분절마다 심근의 관류정도를 4등급으로 나누어 국소적 심근관류를 평가하였다. 결과: 8 단위영상과 16 단위영상 게이트 스펙트에서 국소적 심근관류의 일치도는 85.7% (tau-b=0.786, p<0.001)로 우수하였다. 두 방법간에 1등급의 차이는 100 분절(13.2%), 2등급 차이는 8 분절(1.1 %)이 있었고 3등급 차이는 없었다. 좌심실의 확장기말 용적, 수축기말 용적, 구혈률은 두 방법간에 높은 상관성을 보였으며(r=0.993, 0.989, 0.935), 좌심실 구혈률은 8 단위영상을 사용할 때 평균 1.8% 낮게 측정되어 통계적인 유의성은 있었으나(p<0.05), 그 차이는 크지 않았다. 결론: 8 단위영상과 16 단위영상을 사용한 게이트 심근관류 스펙트에서 국소적 심근관류의 일치도는 우수하였으며, 좌심실의 기능적 계수의 차이도 크지 않았다. 비록 높은 단위영상을 사용했을 때 더 정확하고 자세한 정보를 얻을 수 있다 하더라도, 구혈률과 용적 등을 얻는 일상적인 임상검사에는 8 단위영상 또한 그 역할을 충분히 할 수 있을 것으로 사료된다.

Increased Vascular Endothelial Growth Factor in the Ventricular Cerebrospinal Fluid as a Predictive Marker for Subsequent Ventriculoperitoneal Shunt Infection : A Comparison Study among Hydrocephalic Patients

  • Lee, Jeong-Hyun;Back, Dong-Bin;Park, Dong-Hyuk;Cha, Yoo-Hyun;Kang, Shin-Hyuk;Suh, Jung-Keun
    • Journal of Korean Neurosurgical Society
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    • v.51 no.6
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    • pp.328-333
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    • 2012
  • Objective : The aim of this study is to determine the association between the cerebrospinal fluid (CSF) biomarkers and inflammation, and the predictive value of these CSF biomarkers for subsequent shunt associated infection. Methods : We obtained CSF samples from the patients with hydrocephalus during ventriculoperitoneal (VP) shunt operations. Twenty-two patients were enrolled for this study and divided into 3 groups: subarachnoid hemorrhage (SAH)-induced hydrocephalus, idiopathic normal pressure hydrocephalus (INPH) and hydrocephalus with a subsequent shunt infection. We analyzed the transforming growth factor-${\beta}1$, tumor necrosis factor-${\alpha}$, vascular endothelial growth factor (VEGF) and total tau in the CSF by performing enzyme-linked immunosorbent assay. The subsequent development of shunt infection was confirmed by the clinical presentations, the CSF parameters and CSF culture from the shunt devices. Results : The mean VEGF concentration (${\pm}$standard deviation) in the CSF of the SAH-induced hydrocephalus, INPH and shunt infection groups was $236{\pm}138$, $237{\pm}80$ and $627{\pm}391$ pg/mL, respectively. There was a significant difference among the three groups (p=0.01). Between the SAH-induced hydrocephalus and infection groups and between the INPH and infection groups, there was a significant difference of the VEGF levels (p<0.01). However, the other marker levels did not differ among them. Conclusion : The present study showed that only the CSF VEGF levels are associated with the subsequent development of shunt infection. Our results suggest that increased CSF VEGF could provide a good condition for bacteria that are introduced at the time of surgery to grow in the brain, rather than reflecting a sequel of bacterial infection before VP shunt.

Engineering Application of Direct Shear Box Test for Slope Stability Problem (사면 안정 문제에 대한 직접 전단 시험의 공학적 적용)

  • Ikejiri, Katsutoshi;Shibuya, Satoru;Jung, Min-Su;Chae, Jong-Gil
    • Journal of the Korean Geotechnical Society
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    • v.24 no.12
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    • pp.65-73
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    • 2008
  • In the current practice for slope stability problem in Japan, the shear strength, $\tau$, mobilized along the failure surface is usually estimated based on an empirical approximation in which the cohesion, c, is assumed to be equal to the soil thickness above the supposed slip surface, d(m). This approximation is advantageous in that the result of stability analysis is not influenced by the designers in charge. However, since the methodology has little theoretical background, the cohesion may often be grossly overestimated, and conversely the angle of shear resistance, $\phi$, is significantly underestimated, when the soil thickness above the supposed slip surface is quite large. In this paper, a case record of natural slope failure that took place in Hyogo Prefecture in 2007, is described in detail for the case in which the shear strength along the collapsed surface was carefully examined in a series of direct shear box (DSB) tests by considering the effects of in-situ shear stress along the slip surface. It is demonstrated that the factor of safety agrees with that of in-situ conditions when the shear strength from this kind of DSB test was employed for the back-analysis of the slope failure.

Protective effect of Gabjubaekmok (Diospyros kaki) extract against amyloid beta (Aβ)-induced cognitive impairment in a mouse model (아밀로이드 베타(amyloid beta)로 유도된 인지장애 마우스 모델에서 갑주백목(Diospyros kaki) 추출물의 인지기능 및 뇌 신경세포 보호 효과)

  • Yoo, Seul Ki;Kim, Jong Min;Park, Seon Kyeong;Kang, Jin Yong;Han, Hye Ju;Park, Hyo Won;Kim, Chul-Woo;Lee, Uk;Heo, Ho Jin
    • Korean Journal of Food Science and Technology
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    • v.51 no.4
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    • pp.379-392
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    • 2019
  • The current study investigated the effect of Gabjubaekmok (Diospyros kaki) ethanolic extract (GEE) on $H_2O_2$-induced human neuroblastoma MC-IXC cells and amyloid beta $(A{\beta})_{1-42}$-induced ICR (Institute of Cancer Research) mice. GEE showed significant antioxidant activity that was evaluated based on ABTS, DPPH scavenging activity, and inhibition of malondialdehyde (MDA) and acetylcholinesterase activity. Further, GEE inhibited ROS production and increased cell viability in $H_2O_2$-induced MC-IXC cells. Administration of GEE ameliorated the cognitive dysfunction on $A{\beta}$-induced ICR mice as evaluated using Y-maze, passive avoidance, and Morris water maze tests. Results of ex vivo test using brain tissues showed that, GEE protected the cholinergic system and mitochondrial functions by increasing the levels of antioxidants such as ROS, mitochondrial membrane potential (MMP), and adenosine triphosphate (ATP) against $A{\beta}$-induced cognitive dysfunction. Moreover, GEE decreasd the expression levels of apoptosis-related proteins such as $TNF-{\alpha}$, p-JNK, p-tau, BAX and caspase 3. While, expression levels of p-Akt and $p-GSK3{\beta}$ increased than $A{\beta}$ group. Finally, gallic acid was identified as the main compound of GEE using high performance liquid chromatography.

$^{17}O$ NMR Study On Water Excharge Rate of Paramagnetic Contrast Agents ($^{17}O$ NMR 기법을 이용한 상자성 자기공명조영제의 물분자 교환에 관한 연구)

  • Yongmin Chang;Sung Wook Hong;Moon Jung Hwang;Il Soo Rhee;Duk-Sik Kang
    • Investigative Magnetic Resonance Imaging
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    • v.5 no.1
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    • pp.33-37
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    • 2001
  • Purpose : The water exchange rate between bulk water and bound water is an important parameter in deciding the efficiency of paramagnetic contrast agents. In this study, we evaluated the water exchange rates of various Gd-chelates using oxygen-17 NMR technique. Material and Methods : The samples (Gd-DTPA, Gd-DTPA-BMA, Gd-DOTA, Gd-EOB-DTPA) were prepared by mixing 5% $^{17}O-enriched$ water (Isotech, USA). The pH of the samples was adjusted to physiological value [pH=7.0] by buffer solution. The variable temperature $^{17}O-NMR$ measurements were performed using Bruker-600 (14.1 T, 81.3 MHz) spectrometer. Bruker VT-1000 temperature control units were used to stabilize the temperature. The $^{17}O$ spin-spin relaxation times (T2) were measured using Carr-Purcell-Meiboom-Gill (CPMG)I pulse sequence with 24 echo trains. The variable temperature T2 relaxation data were then fitted into Solomon-Bloembergen equations using least square fit algorithm to estimate the water exchange times. Results : From the measured $^{17}O-NMR$ relaxation rates, the determined water exchange rates at 300K are $0.42{\;}{\mu}s$ for Gd-DTPA, $1.99{\;}{\mu}s$ for Gd-DTPA-BMA, $0.27{\;}{\mu}s$ for Gd-DOTA, and $0.11{\;}{\mu}s$ for Gd-EOB-DTPA. The Gd-DTPA-BMA showed slowest exchange whereas Gd-EOB-DTPA had fastest water exchange rate. In addition, it was found that the water exchange rates (${\tau}_m$) of all samples had exponential temperature dependence with different decay constant. Conclusion : $^{17}O-NMR$ relaxation rate measurements, when combined with variable temperature technique, provide a solid tool for studying water exchange rate, which is very important in investigating the detailed mechanism of relaxation enhancement effect of the paramagnetic contrast agents.

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