Isolated Non-Compaction of the Left Ventricle in a Patient with New-Onset Heart Failure: Morphologic and Functional Evaluation with Cardiac Multidetector Computed Tomography

이헌,김석연,U. Joseph Schoepf 대한영상의학회 2012 Korean Journal of Radiology Vol.13 No.2

We describe a case of new-onset heart failure in a patient in whom cardiac CT enabled the non-invasive diagnosis of isolated non-compaction and associated functional abnormalities of the left ventricle with the concomitant evaluation of coronary arteries. This case highlights the utility of cardiac CT for the morphological and functional evaluation of the heart as a single imaging modality.

하이브리드 광촉매 시스템을 이용한 TNT 활성 평가

이헌,이미리,안현근,정상철 한국공업화학회 2010 한국공업화학회 연구논문 초록집 Vol.2010 No.1

Myocardial Contrast Defect Associated with Thrombotic Coronary Occlusion: Pre-Autopsy Diagnosis of a Cardiac Death with Post-Mortem CT Angiography

이헌,박혜진,차장규,이수경,양경무 대한영상의학회 2015 Korean Journal of Radiology Vol.16 No.5

We report the case of a female who died of suspected acute myocardial infarction. Post-mortem CT angiography (PMCTA) was performed with intravascular contrast infusion before the standard autopsy, and it successfully demonstrated the complete thrombotic occlusion of a coronary artery and also a corresponding perfusion defect on myocardium. We herein describe the PMCTA findings of a cardiac death with special emphasis on the potential benefits of this novel CT technique in forensic practice.

A Case Report of Congenitally Corrected Transposition of Great Arteries: Morphologic and Functional Evaluation with Cardiac CT

이헌,박병원 대한영상의학회 2013 대한영상의학회지 Vol.69 No.3

Congenitally corrected transposition of the great arteries (ccTGA) is a rare congenital anomaly characterized by atrioventricular and ventriculoarterial discordance. We report a case of new-onset heart failure in a 69-year-old female in whom cardiac CT demonstrated ccTGA without the associated cardiovascular anomalies. In this case, cardiac CT was useful for elucidating the rare and unexpected congenital etiologies of abrupt-onset heart failure in an old patient by the simultaneous evaluation of cardiac morphology and function as a single study (inserted).

조영증강 CT촬영후 발생한 대량의 심실내 공기 색전: 증례 보고

이헌 대한영상의학회 2006 대한영상의학회지 Vol.54 No.5

Venous air embolism, although considered as a rare condition, it occurs more frequently than it is recognized. Air embolism has been reported to occur after contrast-enhanced CT examination in up to 23% of patients. Because these emboli are usually small to moderate size and they are venous, the patients are usually asymptomatic. However, a large amount of intravenous air can cause disastrous consequences and it can be fatal. The author reports here on 2 cases of symptomatic massive intraventricular air embolism after contrast enhanced CT with a brief review of the pathophysiology and the recommended treatment of air embolization. 조영제 주입과 관련된 정맥 내 공기 색전은 생각보다 드물지 않은 합병증으로 조영증강 CT 후 23%까지 관찰되는 것으로 보고되어 있다. 이들 대부분은 색전된 공기의 양이 적고 증상이 없어 치료가 필요하지 않지만 대량의 공기 색전인 경우 치명적일 수 있다. 저자는 조영제 주입과 관련하여 발생한 대량의 심실 내 공기 색전 2예를 경험하였기에 영상소견, 색전의 병태생리, 방사선과 내에서의 초기대처 방법 등을 간단한 문헌고찰과 더불어 보고하고자 한다.

Overview of Phase change memory

이헌 한국화학공학회 2007 화학공학의이론과응용 Vol.10 No.1

This coming 21st century is a digital era based on information revolution. All of human being``s intellectual products will be reformed as the form of digital format which is represented as the combination of ``0`` and ``1`` and they will be transferred from the place to the place in a blink of time. In order to realize such a drastic change, new information storage technology must be invented. It also means that the invention of new materials and devices for improved information storage must be followed. Due to the new emerging markets of personal digital devices, including PDA, digital camera/camcoder, cellular phone, MP3 player and e-book reader, flash memory market is continuously increasing. However, flash memory has somewhat fatal disadvantages such as high voltage operation, limited endurance and slow write/read speed and thus there are various efforts to replace flash memory device to new improved non-volatile memory. Among new non-volatile devices, PCRAM is regarded as one of the most promising non-volatile memory device which can replace the flash memory. In this presentation, operation principle, advantages and disadvantages of phase change memory will be explained and be compared with MRAM and FRAM.

사람 단핵구 종양괴사인자의 유도 , 정제 . 크로닝 및 발현

이헌,김정현,김승수 ( Hun Lee,Jeong Hyun Kim,Soung Soo Kim ) 생화학분자생물학회 1989 BMB Reports Vol.22 No.4

The gene encoding subtilisin Carlsberg from Bacillus licheniformis has been isolated by the $quot;in-situ colony hybridization technique$quot; using synthetic oligonucleotide as a probe. Pstl digested chromosomal DNA was ligated into the Pstl site of pBR322. The ligation mixture was used to transform E. coli and the transformants were screened by the in-situ colony hybridization technique. Out of 3,500 colonies screened, one colony was hyridized to the probe. The recombinant DNA of this positive clone was named pS113. Digestion of pS113 by restriction endonucleases showed that the size of the inserted DNA was about 4.6 Kb and the restriction map was nearly like that of Jacobs`. To express the gene in Bacillus, Pstl digested pS113 was ligated into the Pstl site of pMK4. The ligation mixture was used to transform B. licheniformis and the transformants were assayed on casein plate for protease secretion. We obtained a clony having a distinctively large halo.

Fractional Laser Photothermolysis for Treatment of Facial Wrinkles in Asians

이헌,윤진숙,이상열 대한안과학회 2009 Korean Journal of Ophthalmology Vol.23 No.4

Purpose: To evaluate the safety and efficacy of fractional photothermolysis (FP) in the treatment of facial wrinkles in Asians. Methods: A total of 27 Korean patients (Fitzpatrick type Ⅲ or Ⅳ) received 2-3 FP treatment sessions (Sellas; Dinona Inc., Seoul, Korea) spaced two weeks apart. Treatments were performed at settings of 7 to 9 mJ/microthermal treatment zone (MTZ) and a density of 1000 MTZ/㎠. Standardized digital photographs were obtained before each treatment and three months after the final treatment. The evaluations of clinical photographs were performed by three physicians blinded to the study subjects using a five-point grading scale. In addition, the patients’ perceived degree of improvement was assessed three months after the final treatment using a five-point grading scale. Side effects were monitored at each follow-up visit. Results: The physicians’ assessed degrees of improvement were excellent in three patients (12%), significant in ten (40%), and moderate in seven (28%). The patients’ self-assessed degrees of improvement were excellent in five patients (20%), significant in 11 (44%), and moderate in six (24%). Adverse events were limited to transient pain, erythema and edema, except in one case of transient postinflammatory hyperpigmentation. Conclusions: FP is an effective treatment modality for reducing facial wrinkles with minimal side effects in Asian patients.

발명의 진보성 판단과 기술적 과제- 특허법원 2014. 1. 28. 선고 2013허1313 판결

이헌 서울대학교 기술과법센터 2015 Law & technology Vol.11 No.3

Tumor Necrosis Factor from Human Peripheral Monocytes: Induction, Purification, Gene Cloning and Expression

이헌,김정현,김승수,Lee, Hun,Kim, Jeong-Hyun,Kim, Soung-Soo 생화학분자생물학회 1989 한국생화학회지 Vol.22 No.4

LPS와 PMA를 다양하게 조합하여 사람 단핵구 세포를 처리해서 이들로부터 사람 종양괴사인자가 생성되었다. 특히 사람 단핵구 세포 ($2{\times}10^7$ 세포/ml)를 PMA (10 ng/ml)로 먼저 6시간 처리하고 LPS $(20{\mu}g/ml)$로 나중에 6시간 처리하였을 때 가장 높은 종양괴사인자 활성을 얻을 수 있었다. 유도한 종양괴사인자는 혈청이 포함되지 않은 배양배지로부터 DEAE-Sephacel 이온교환 크로마토그라피, Sephadex G-75 gel filtration, SDS-PAGE 용출방법에 의해 정제하였다. SDS-PAGE 방법에 의해 결정된 종양괴사인자의 분자량은 대략 17,800 정도였고 Sephadex G-150 gel filtration 방법에 의해 얻은 native 분자량은 68,000 정도였다. 반면에 ${\lambda}gt11$ 발현 운반체 system에 의해 E. coli에서 발현된 recombinant 사람 종양괴사인자의 분자량은 Western blot 분석과 Sephadex G-150 gel filtration 방법에 의해 모두 17,400 정도로 나타났다. 이 같은 결과들로 보아 종양괴사인자의 monomer 형태와 multimer 형태가 모두 생물학적으로 활성을 갖는다는 것을 알 수 있다. Human tumor necrosis factor(TNF) was produced from human peripheral monocytes by treatment of the cells with various combinations of lipopolysaccharide(LPS) and phorbol myristate acetate(PMA). The best induction of TNF activity could be achieved when human peripheral monocytes ($2{\times}10^7$ cells/ml) were first treated with 10 ng/ml of PMA for 6 hours followed by 6 hours treatment with LPS$(20{\mu}g/ml)$. Induced TNF from serum-free culture media was purified by DEAE-Sephacel ion exchange chromatography, Sephadex G-75 gel filtration and SDS-PAGE elution. The molecular weight of the TNF as determined by SDS-PAGE was about 17,800, while the native molecular weight obtained by Sephadex G-150 gel filtration was 68,000. On the other hand, the molecular weight of recombiant human TNF obtained in E. coli by ${\lambda}gt11$ expression vector system was estimated to be 17,400 by Western blot analysis and Sephadex G-150 gel filtration. These results suggest that both monomeric and multimeric forms of TNF are biologically active.