• Korean Journal of Radiology
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• 제1권3호
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• pp.152-158
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• 2000

Objective: The purpose of this study was to compare the effectiveness of MR urography (MRU) with that of ultrasonography (US) in the evaluation of urinary tract when this failed to opacify during excretory urography (EXU). Materials and Methods: Twelve urinary tracts in 11 patients were studied. In each case, during EXU, the urinary system failed to opacify within one hour of the injection of contrast media, and US revealed dilatation of the pelvocalyceal system. Patients underwent MRU, using a HASTE sequence with the breath-hold technique; multi-slice acquisition was then performed, and the images were reconstructed using maximal intensity projection. Each set of images was evaluated by three radiologists to determine the presence, level, and cause of urinary tract obstruction. Results: Obstruction was present in all twelve cases, and in all of these, MRU accurately demonstrated its level. In this respect, however, US was successful in only ten. The cause of obstruction was determined by MRU in eight cases, but by US in only six. In all of these six, MRU also successfully demonstrated the cause. Conclusion: MRU is an effective modality for evaluation of the urinary tract when this fails to opacify during EXU, and appears to be superior to US in demonstrating the level and cause of obstruction.

• Investigative Magnetic Resonance Imaging
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• 제17권3호
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• pp.181-191
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• 2013

목적: 급성 신부전 쥐 모델에서 상자성 철 산화물 (superparamagnetic iron oxide(SPIO)로 표지한 인간탯줄혈관내피 세포를 자기공명영상으로 추적할 수 있는지 그 유용성을 평가하고자 하였다. 대상과 방법: 인간탯줄혈관내피 세포를 SPIO와 poly-L-lysine (PLL) 혼합물로 표지 하였다. SPIO 농도에 따라서 이완율, 세포 생존율, 표지 안정성을 SPIO 농도의 변화에 따라 평가하였다. 인간탯줄혈관내피 세포를 급성 신부전 쥐 모델에서 꼬리정맥을 통하여 주사하였다. MR을 이용한 추적 검사는 $T2^*$ 경사에코 MR 영상을 이용하였다. 1, 3, 5, 7일째 추적한 MR 영상 소견을 조직 소견과 서로 견주어 보았다. 결과: SPIO-PLL 혼합물을 표지 한 후 Prussian blue 염색에서 평균 $98.4{\pm}2.4%$ 세포가 양성반응을 보였다. 3일과 5일 후 측정한 이완율은 1일에 비해 큰 차이가 없었다. 인간탯줄혈관내피 세포를 SPIO로 표지 한 후 안정성이 유지됨을 알 수 있었다. 추적 MR 영상에서 급성신부전을 유도한 왼쪽 신장 외곽 신 수질에서 신호강도 소실을 보였으나 오른쪽은 정상이었다. 3, 5, 7일 후 촬영한 영상에서 왼쪽 신 수질에서 보인 신호강도 소실이 점차 사라졌으나 오른쪽 신장에서는 여전히 특별한 변화를 보이지 않았다. 조직학 검사에서도 MR 영상의 신호강도 소실이 Prussian blue 염색을 보인 부분과 일치하였다. 면역화학적 분석에서 신 수질에서 보인 세포들이 인간탯줄혈관내피 세포임을 확인하였다. 결론: MR 영상은 급성 신부전 치료의 한 방법인 세포 치료의 경우 세포 추적 검사에 유용하게 사용될 수 있음을 확인하였다.

• 보험의학회지
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• 제29권2호
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• pp.18-21
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• 2010

Background: The kidney transplantation is increasing. The kidney donation of a living donor is more common in Korea than in other countries. Underwriters may encounter a case of a kidney donor. So we need to determine medical risk for a living kidney donor. Methods: Comparative mortality figures were calculated from a source article using mortality analysis methods. Results: Mortality Ratio of a living kidney donor was estimated to 106%, and Excess Death Rate was 0.89 per 1000. Discussion: A healthy kidney donor is quite within standard, even better in terms of medical risk.

• Journal of Magnetics
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• 제17권3호
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• pp.219-224
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• 2012

In the present study, changes in signal-to-noise ratio (SNR) and apparent diffusion coefficient (ADC) of the diffusion-weighted images in the normal livers were investigated using changes in b values in 1.5 T MR (magnetic resonance) instruments. Respective diffusion-weighted images and ADC map images were obtained from 20 healthy individuals by increasing b values from 50 to 400 and 800 $s/mm^2$ using 1.5T MR scanner between January 2011 and November 2011. At each ADC map image obtained at each b value, ADCs in the right hepatic lobe, spleen and kidney were measured. As a result, ADCs of the right hepatic lobe, spleen and kidney have gradually decreased in the diffusion-weighted images in accordance with the reduced b value. This outcome may be used as preliminary data for applications to various abdominal diseases.

• Korean Journal of Radiology
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• 제25권3호
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• pp.257-266
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• 2024

Objective: To investigate molecular and functional consequences of additional exposures to iodine- or gadolinium-based contrast agents within 24 hours from the initial intravenous administration of iodine-based contrast agents through an animal study. Materials and Methods: Fifty-six Sprague-Dawley male rats were equally divided into eight groups: negative control, positive control (PC) with single-dose administration of CT contrast agent, and additional administration of either CT or MR contrast agents 2, 4, or 24 hours from initial CT contrast agent injection. A 12 µL/g of iodinated contrast agent or a 0.47 µL/g of gadolinium-based contrast agent were injected into the tail vein. Serum levels of blood urea nitrogen, creatinine, cystatin C (Cys C), and malondialdehyde (MDA) were measured. mRNA and protein levels of kidney injury molecule-1 (KIM-1) and neutrophil gelatinase-associated lipocalin (NGAL) were evaluated. Results: Levels of serum creatinine (SCr) were significantly higher in repeated CT contrast agent injection groups than in PC (0.21 ± 0.02 mg/dL for PC; 0.40 ± 0.02, 0.34 ± 0.03, and 0.41 ± 0.10 mg/dL for 2-, 4-, and 24-hour interval groups, respectively; P < 0.001). There was no significant difference in the average Cys C and MDA levels between PC and repeated CT contrast agent injection groups (Cys C, P = 0.256-0.362; MDA, P > 0.99). Additional doses of MR contrast agent did not make significant changes compared to PC in SCr (P > 0.99), Cys C (P = 0.262), and MDA (P = 0.139-0.771) levels. mRNA and protein levels of KIM-1 and NGAL were not significantly different among additional CT or MR contrast agent groups (P > 0.05). Conclusion: A sufficient time interval, probably more than 24 hours, between repeated contrast-enhanced CT examinations may be necessary to avoid deterioration in renal function. However, conducting contrast-enhanced MRI on the same day as contrast-enhanced CT may not induce clinically significant kidney injury.

• 대한한방소아과학회지
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• 제22권1호
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• pp.13-24
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• 2008

Objectives This study was designed to analyze the clinical studies on Mental retardation(MR) in traditional Chinese medicine(TCM). Methods For this study, we searched the clinical studies on MR, which had been published from 2003 to 2007, through web site CNKI(中國知識基礎設施工 http://www.cnki.net). There were 17 clinical studies and we focused on those studies. Results 1. In those Chinese studies, they used following words to describe Mental retardation; 小人弱智($xi\check{a}o\acute{e}rru\grave{o}zh\grave{i}$), 智能發育不全($zh\grave{i}n\acute{e}ngf\bar{a}y\grave{u}buqu\acute{a}n$), 智力低下($zh\grave{i}l\grave{i}d\bar{i}xi\grave{a}$), 精神發育遲滯($j\bar{i}ngsh\acute{e}f\bar{a}y\grave{u}ch\acute{i}zh\grave{i}$), 智能落后($zh\grave{i}n\acute{e}nglu\grave{o}h\grave{o}u$), 智能落后($zh\grave{i}n\acute{e}ngch\acute{i}hu\check{a}n$), 失天愚型患人($xi\bar{a}nti\bar{a}ny\acute{u}x\acute{i}nghu\grave{a}n'\acute{e}r$). 2. There were many kinds of TCM treatment methods for MR, such as herbal medicine, acupuncture, electroacupunture, acupoint injection, Chuna therapy, and special education. And those TCM treatments methods showed higher efficacies in the treatment of MR compared with Western medicine. 3. Mental retardation was related with the deficiency of heart, kidney, liver, spleen(心虛, 腎虛, 肝虛, 脾虛) and the pathological mechanism of Phlegm(絹) and Blood stasis(慫沂)in the studies about the Bian Zheng-the types of differential diagnosis- of MR. 4. Most of studies used Intelligence Quotient(IQ) to assess the efficacy of TCM treatment of MR. And the duration of treatment, the degree of illness, the age of patient, and the cause of illness affected the prognosis of MR. Conclusions These results suggest that traditional medicine could be one of the useful treatments on MR. And these results could be used in the clinical practices and studies on MR in Korea.

• Investigative Magnetic Resonance Imaging
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• 제2권1호
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• pp.39-49
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• 1998

신장질환의 자기공명영상은 영상시간이 단축되면서 이용이 확대되고 있다. 다른 영상진단법에 비하여 높은 연부조직대조도, 다면영상능, MRI용 조영제의 안전성 등의 장점에도 불구하고 신장질환의 영상진단에 있어서 아직은 일반적으로 초음파검사와 CT의 보조적 역할을 하고 있는 것이 사실이다. 그러나 선택적으로는 MRI로만 평가할 수 있는 소견들이 신장질환의 진단에 도움이 되기도 한다.

• 대한방사성의약품학회지
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• 제1권2호
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• pp.130-136
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• 2015

We evaluate the influence of MR contrast agent on positron emission tomography (PET) image using phantom, animal and human studies. Phantom consisted of 15 solutions with the mixture of various concentrations of Gd-based MR contrast agent and fixed activity of [$^{18}F$]FDG. Animal study was performed using rabbit and two kinds of MR contrast agents. After injecting contrast agent, CT or MRI scanning was performed at 1, 2, 5, 10, and 20 minutes. PET image was obtained using clinical PET/CT scan, and attenuation correction was performed using the all CT images. The values of HU, PET activity and MRI intensity were obtained from ROIs in each phantom and organ regions. In clinical study, patients (n=20) with breast cancer underwent sequential acquisitions of early [$^{18}F$]FDG PET/CT, MRI and delayed PET/CT. In phantom study, as the concentration increased, the CT attenuation and PET activity also increased. However, there was no relationship between the PET activity and the concentration in the clinical dose range of contrast agent. In animal study, change of PET activity was not significant at all time point of CT scan both MR contrast agents. There was no significant change of HU between early and delayed CT, except for kidney. Early and delayed SUV in tumor and liver showed significant increase and decrease, respectively (P<0.05). Under the condition of most clinical study (< 0.2 mM), MR contrast agent did not influence on PET image quantitation.

• Journal of Microbiology and Biotechnology
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• 제6권1호
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• pp.7-11
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• 1996

MR-387Al (ARPA-Val-Pro) and A2 (AHPA-Val-Hyp) were prepared as aminopeptidase N inhibitors through the synthesis of peptide MR-387A and B analogues which contained 3-amino-2-hydroxy-4-phenyl butanoic acid (ARPA) as a zinc-chelating moiety. They are competitive inhibitors of aminopeptidase N with inhibition constants(Ki) of 4.1 $\times 10^{-7}\;and 1.1 \times 10^{-6}$ M, respectively. MR-387Al also strongly inhibited aminopeptidase B of human myelogenous leukemia K-562 cell with $IC_50$ of 0.35 $\mu$ M. Inhibitions of aminopeptidase N activity by ARPA-bearing inhibitors of various peptide chain lengths also have been studied. $IC_ 50$ values of AHPA-Val (bestatin), ARPA-Val-Pro (MR-387Al) and ARPA-Val-Pro-Leu (MR-387C) compared against porcine kidney aminopeptidase N were 20.1, 0.60 and 0.08 $\mu$ M, respectively. These results support that a multiple interaction between the $S_1\to S'_3$ sites of aminopeptidase N and the $P_1\to P'_3$ of the inhibitor plays a crucial role in stabilizing strongly the enzyme-inhibitor complex.

• 약학회지
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• 제28권3호
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• pp.139-147
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• 1984

L-PHA, a lectin having lymphoagglutinating activity but devoid of erythroagglutinability which is contained in Korean white kidney bean (Phaseolus vulgaris L.), was isolated and purified through several techniques such as ion exchange chromatography, hydroxyapatite column and affinity chromatography. Purified L-PHA was identified as a single band by polyacrylamide disc gel electrophoresis. The molecular weight of the L-PHA was estimated about 125, 000 daltons by polyacrylamide gel electrophoresis and it was turned out having one subunit (probably dimer of the Yachnin's model) of Mr~60, 000. Immunochemical studies also tried and these results reconfirmed the purity of this L-PHA.