競馬大會

李學鍾 朝鮮思想通信社 1928 朝鮮思想通信 Vol.- No.802

초음파 조영제의 합성 및 합성된 초음파 조영제의 특성 분석

이학종,윤태종,윤영일 대한초음파의학회 2013 ULTRASONOGRAPHY Vol.32 No.1

Purpose: The purpose of this study is to establish the methodology regarding synthesis of ultrasound contrast agent imaging, and to evaluate the characteristics of the synthesized ultrasound contrast agents, including size or degradation interval and image quality. Materials and Methods: The ultrasound contrast agent, composed of liposome and SF6, was synthesized from the mixture solution of 21 μmol DPPC (1, 2-Dihexadecanoyl-sn-glycero-3-phosphocholine, C40H80NO8P), 9 μmol cholesterol, 1.9μmol of DCP (Dihexadecylphosphate, [CH3(CH2)15O]2P(O)OH), and chloroform. After evaporation in a warm water bath and drying during a period of 12-24 hours, the contrast agent was synthesized by the sonication process by addition of buffer and SF6gas. The size of the contrast agent was controlled by use of either extruder or sonication methods. After synthesis of contrast agents, analysis of the size distribution of the bubbles was performed using dynamic light scattering measurement methods. The degradation curve was also evaluated by changes in the number of contrast agents via light microscopy immediate, 12 hours, 24 hours, 36 hours, 48 hours, 60 hours, 72hours, and 84 hours after synthesis. For evaluation of the role as an US contrast agent, the echogenicity of the synthesized microbubble was compared with commercially available microbubbles (SonoVue, Bracco, Milan, Italy) using a clinical ultrasound machine and phantom. Results: The contrast agents were synthesized successfully using an evaporationdrying-sonication method. The majority of bubbles showed a mean size of 154.2nanometers, and they showed marked degradation 24 hours after synthesis. ANOVA test revealed a significant difference among SonoVue, synthesized contrast agent,and saline (p < 0.001). Although no significant difference was observed between SonoVue and the synthesized contrast agent, difference in echogenicity was observed between synthesized contrast agent and saline (p < 0.01). Conclusion: We could synthesize ultrasound contrast agents using an evaporation-drying-sonication method. On the basis of these results, many prospective types of research, such as anticancer drug delivery, gene delivery, including siRNA or microRNA, targeted molecular imaging, and targeted therapy can be performed. 목적: 본 연구는 초음파 조영제를 직접 합성하고 그 크기및 소멸 시간 등의 특성을 분석하며, 기존의 초음파 조영제와의 영상을 비교하여 앞으로 초음파 조영제를 매개로 한영상 유도 하 약물 및 유전자 치료제의 전달 시스템 구축의기본을 갖추고자 한다. 대상 및 방법: 초음파 조영제는 21마이크로 몰의DPPC(1, 2-Dihexadecanoyl-sn-glycero-3-phosphocholine,C40H80NO8P), 9 마이크로 몰의 콜레스테롤,1.9 마이크로 몰의 DCP(Dihexadecylphosphate,[CH3(CH2)15O]2P(O)OH) 및 클로로포름 및 SF6 기체를이용하여 합성하였다. 약 12-24시간의 동결건조 후에 초음파 조영제는 SF6 기체와 초음파 처리(sonication) 법을이용하여 합성하였고 그 초음파 조영제의 크기는 압출기를 이용하여 일정한 크기로 조정하였다. 합성된 초음파 조영제는 동적 광산란 측정법(dynamic light scattering measurement)을 이용하여 그 크기를 분석하였다. 한편 합성한 초음파 조영제의 소멸 양상을 평가하기 위하여 광학 현미경을 이용하여 그 숫자를 합성 직후,12시간, 24시간, 36시간, 48시간, 60시간, 72시간 및 84시간 후에 평가하였다. 초음파 조영제로서의 효과를 평가하기 위하여 모형을 만들어 현재 임상적으로 사용되고 있는 초음파 조영제와 그 에코를 비교 분석하였다. 결과: 초음파 조영제는 동결건조-초음파 처리 방법을통하여 성공적으로 합성 할 수 있었다. 합성된 초음파 조영제는 154.2 nm의 정점 (peak)에서 가장 많이 분포하였으며 합성 후 24시간부터는 입자의 숫자들이 감소하는 양상을 보였다. 소노뷰와 합성된 초음파 조영제의 에코밝기는유의한 차이를 보이지 않았으나 소노뷰와 생리식염수 및합성된 초음파 조영제와 생리식염수의 에코 밝기는 통계적으로 유의한 차이를 보였다 (p < 0.01). 결론: 본 연구를 통하여 초음파 조영제를 직접 합성할 수있는 방법을 습득할 수 있었고 그 크기 및 특성을 분석할수 있었다.

敎育小言

李學鍾 朝鮮思想通信社 1928 朝鮮思想通信 Vol.- No.802

여성경영자와 Leadership

이학종 이화여자대학교 경영연구소 1970 여성과 경영 Vol.1 No.-

전립선암의 영상의학적 소견

이학종 대한의사협회 2015 대한의사협회지 Vol.58 No.1

The clinical significance of prostate cancer is increasing markedly with an increased population of aged persons and Westernized behavior patterns. Accordingly, the role of prostate imaging is also becoming important in the early diagnosis of prostate cancer. Transrectal prostate ultrasound (TRUS) is used for the estimation of prostate volume as well as the detection of prostate cancer, seen as focal hypoechoic lesions. Almost all prostate tissue biopsies are performed under the guidance of TRUS. One of the important issues in prostate imaging is the visualization of suspected prostate cancer lesions. In order to obtain detailed information regarding a suspected prostate lesion, contrast-enhanced imaging is utilized, using microbubbles and elastography. In addition, magnetic resonance imaging-ultra sonography (MRI-US) fusion imaging, in which the ultrasound machine archives magnetic resonance (MR) images and facilitates MRI-US fusion imaging-guided biopsy, has been revealed to be superior to conventional ultrasound-guided biopsy. Prostate MR is usually performed in patients with confirmed prostate cancer, after prostate biopsy for the evaluation of tumor staging or follow-up changes after chemotherapy, hormone therapy, or radiation therapy. In particular, the evaluation of seminal vesicles is crucial for accurate identification of tumor staging. Advanced functional MR techniques, including diffusion-weighted imaging, dynamic contrast-enhanced imaging, and MR spectroscopy, also have potential in the localization of prostate cancer. In summary, the role of prostate imaging in the diagnosis and localization of prostate cancer is increasing. Advanced technologies in ultrasound and MR imaging may have important roles in localization of prostate cancer and image-guided biopsy.

陪審制度と法曹

李學鍾 朝鮮思想通信社 1928 朝鮮思想通信 Vol.- No.802

항암제 치료에 있어서 영상 생체표지자로서의 초음파 조영제 영상검사: 파크리탁셀과 이종이식 종양 모델을 이용한 예비연구

이학종,황성일,변종회,공훈영,정현숙,강미라 대한초음파의학회 2011 ULTRASONOGRAPHY Vol.30 No.2

Purpose: We wanted to assess tumor angiogenesis of human prostate cancer cells (PC3) implanted in mice before and after paclitaxel injection via contrast-enhanced ultrasonography (CEUS). Materials and Methods: Twelve mice were injected with human prostate cancer cells (PC3) on the back or hind limbs. The mice were grouped into two groups; one was the paclitaxel treated group (n = 6) and the other was the control group, which was treated with normal saline (n = 6). Before injection of paclitaxel into the peritoneal cavity, baseline CEUS was performed by the administration of 500 μl (1×108microbubbles) of contrast agent. The area under the curve (AUC) up to 50 seconds after contrast injection was derived from the time-intensity curves. After injection of paclitaxel or saline, one week follow up CEUS studies were performed. The changes of the tumor volume and the AUC in both two groups were evaluated. After CEUS, the mice were sacrificed and the microvessel density (MVD) was compared. Results: In the paclitaxel treated group, the AUC from CEUS showed a significant decrease one week after paclitaxel administration (p = 0.03), even though the tumor volume showed no significant changes (p = 0.116). In the control group, there was no significant decrease of the AUC (p = 0.173). Pathologically, there was a significant difference of microvessel density in both groups (p = 0.002). Conclusion: The AUC from the time intensity curve derived from CEUS showed early change in response to the anti-cancer drug treatment in advance of a tumor size response. The findings of CEUS could be an imaging biomarker for assessing the tumor response to anti-cancer drug treatment.

米價の前途如何

李學鍾 朝鮮思想通信社 1928 朝鮮思想通信 Vol.- No.803

Michael A. Cusmano and Richare W. Selby, Microsoft Secrets

이학종 연세대학교 경영연구소 1996 연세경영연구 Vol.33 No.1

사례연구 : 필립 모리스 그룹

李學鍾 연세대학교 경영연구소 1992 연세경영연구 Vol.29 No.1