정상, 고안압증, 녹내장 의증, 녹내장안에서 매트릭스 시야계와 험프리 표준 자동 시야계간의 결과 비교

천현철,정우진,노세현,Hyun Chul Cheon,M,D,Woo Jin Jeung,M,D,Sae Heun Rho,M,D 대한안과학회 2007 대한안과학회지 Vol.48 No.5

Purpose: To study the correlation between the Humphrey standard automated perimetry (SAP) and the Humphrey Matrix Frequency Doubling Technology (FDT) perimetry and diagnostic usefulness of the Humphrey Matrix FDT perimetry. Methods: This study included 170 eyes of 170 patients. The 170 eyes were classified into 50 normal eyes, 20 ocular hypertensive eyes, 50 glaucoma-suspect eyes and 50 glaucomatous eyes. All subjects were examined with the Humphrey Matrix perimetry and the Humphrey standard automated perimetry. We studied the correlations between mean deviation (MD) and pattern standard deviation(PSD) of the Humphrey SAP and those of the Humphrey Matrix perimetry, respectively, in each of the classified group. Results: Overall, MD and PSD of the Humphrey SAP were significantly correlated with MD and PSD of the Humphrey Matrix perimetry, respectively. However, MD and PSD of the Humphrey Matrix perimetry were not showed a significant correlation in normal subjects (P>0.05). Conclusions: In this study, there were significant correlations between the MD and PSD of the SAP and those of the Humphrey Matrix perimetry in glaucoma, glaucoma-suspect and ocular hypertension. These finding suggests the Humphrey Matrix perimetry has performance characteristics similar to SAP and diagnostic value.

골막하 농양을 동반한 심한 안와연조직염의 치료로서 고용량 스테로이드 병용요법의 임상 효과

천현철,박정민,이진화,안희배,Hyun Chul Cheon,Jung Min Park,Jin Hwa Lee,Hee Bae Ahn 대한안과학회 2006 대한안과학회지 Vol.47 No.12

Purpose: To investigate the effect of corticosteroids in the treatment of orbital cellulites with subperiosteal abscess. Methods: The medical records of 4 patients treated for orbital cellulitis with subperiosteal orbital abscess were reviewed. The class and dose of corticosteroids, surgical drainage, treatment course and clinical outcomes were reviewed. Results: All patients received corticosteroids showed satisfactory results during 4.5 months of average follow up. Only one patient have been decreased visual acuity. Complications were minimal including mild hypokalemia, increased hepatic enzyme including aspartate aminotransferase and alanine aminotransferase. Conclusions: The use of corticosteroids may be beneficial in the treatment of orbital cellulitis with subperiosteal abscess.

안구표면 편평상피세포 암종

천현철,이동열,박우찬,안희배,Hyun Chul Cheon,Dong Yeoul Lee,Woo Chan Park,Hee Bae Ahn 대한안과학회 2006 대한안과학회지 Vol.47 No.12

Purpose: To assess the characteristics and treatments of ocular surface squamous neoplasms (OSSN). Methods: We analyzed four representative cases of squamous neoplasms present on the ocular surface and discussed a new paradigm for the diagnosis and management of such lesions. Conclusions: Conjunctival and corneal tumors differentiated to squamous cells are rare. OSSN has various clinical appearances, and because OSSN itself is either malignant or has potential to become malignancy, precise discrimination and adequate treatment methods are necessary. We hope that the results from this study provide a basic source of information for diagnosing and treating OSSN.

생체 내에서 배양한 각막윤부 상피세포 이식술의 장기 경과 관찰 결과

천현철,신동민,이동준,박우찬,Hyun Chul Cheon,M,D,Dong Min Shin,M,D,Dong Joon Lee,M,D,Woo Chan Park,M,D 대한안과학회 2008 대한안과학회지 Vol.49 No.3

`Purpose: To investigate the characteristics and the results of long-term follow-up of limbal epithelial cells cultivated in vivo on amniotic membranes (LIVAM) in corneal limbal deficiency. Methods: Twenty-two eyes of twenty-two patients diagnosed with corneal limbal deficiency underwent transplantation of in vivo cultivated corneal limbal epithelial cells on the amniotic membrane. Biopsy and immunohistochemical staining (AE5, MUC5AC) of the amniotic membrane cultivated for one week were performed to verify that the cultivated epithelial cells on the amniotic membrane were corneal epithelial cells. Impression cytology was performed to evaluate the characteristics of the transplanted corneal limbal epithelial cells at postoperative 1 week, 3 months, 6 months, and 1 year. Results: Successful epithelial growth was observed on the amniotic membrane at one week. The epithelial cells were confirmed to be corneal epithelial cells by immunohistochemical staining. Transplanted in vivo cultivated corneal epithelial cells were confirmed to have corneal specificity by impression cytology and immunohistochemical staining at postoperative 1 week, 3 months, 6 months, and 1 year. Conclusions: In vivo cultured corneal epithelial cells showed morphological and immunohistochemical findings similar to those of normal corneal epithelial cells. Transplanted in vivo cultivated corneal epithelial cells were maintained and showed the characteristics of corneal epithelial cells. Transplantation of in vivo cultivated corneal limbal epithelial cells can be performed to reconstruct the corneal limbus in treating corneal limbal deficiency. `

인 흡착을 위한 Mill Scale 전처리 및 Magnetite 제조 연구

천현철(Hyun Cheol Chun),최영균(Young Gyun Choi) 大韓環境工學會 2015 대한환경공학회지 Vol.37 No.4

철강공장의 열연공정에서 발생하는 폐부산물인 mill scale을 원료로 하여 인흡착에 효율적인 무기흡착제인 magnetite를 생산하고자 하였다. Mill scale의 주요 구성성분은 wustite (FeO), magnetite (FeO), hematite (FeO)였으며, 산처리를 수행할 경우 대부분의 wustite가 magnetite와 hematite로 전환되었다. Mill scale의 산처리는 HCl과 H₂O₂를 이용하여, 염기처리는 NaOH이용하여, 산-염기 복합처리는 H₂SO₄와 NaOH를 이용하여 수행하였다. Oil 제거 및 DI water로 rinsing만 한 경우, 인 흡착용량은 0.28 mgP/g으로 나타난 반면, 염기처리를 한 경우 0.68, 산처리를 한 경우 1.19 mgP/g으로 인 흡착용량이 증가하였다. 산-염기 복합처리 과정을 통해 단일상의 magnetite 입자를 얻을 수 있었으며, 이 입자의 인 흡착용량은 3.11 mgP/g 이상인 것으로 파악되었다. 산화철의 인 흡착에 대한 동력학적 특성 분석결과 Freundlich와 Langmuir 두 등온 흡착모델 모두 magnetite의 인흡착 거동을 잘 모사하였다. Freundlich 모델의 흡착능(K)과 흡착강도(1/n)를 조사한 결과, 온도가 증가할수록 강한 흡착능을 보이는 것으로 나타났다. Langmuir 모델 적용결과 최대 흡착용량은 20℃에서 5.1 mgP/g인 것으로 파악되었다. In steel factory, hot roller cleaning process produces a lot of iron oxide particles called as mill scale. Major components of these particles are wustite (FeO), magnetite (Fe3O₄), and hematite (Fe₂O₃). In this study, we tried to produce pure magnetite from the mill scale because of the largest phosphate adsorption capacity of the magnetite. The mill scale was treated with acid (HCl+H₂O₂), base (NaOH), and acid-base (H₂SO₄+NaOH). Batch adsorption tests showed the acid and/or base treatment could increase the phosphate adsorption capacity of the iron oxides from 0.28 to over 3.11 mgP/g. Magnetite, which could be obtained by acid and base treatment of the mill scale, showed the best adsorption capacity. From the kinetic analysis, both Freundlich and Langmuir isotherm well described the phosphate adsorption behavior of the magnetite. In Langmuir model, maximum phosphate adsorption capacity was found to be 5.1 mgP/g at 20℃.

수중에서의 비소 흡착제거 적정 기술: 역사 및 적용사례

천현철(Hyunchul Chun),이민형(Minhyeong Lee),최영균(Younggyun Choi) 적정기술학회 2016 적정기술학회지(Journal of Appropriate Technology) Vol.2 No.1

수중에서의 비소제거를 위한 방법으로 흡착제를 사용한 적정기술 적용사례를 산업 부산물 및 폐기물 계열, 금속물질 계열, 활성탄 계열의 흡착제를 활용한 경우로 구분하여 정리하였다. 비소제거를 위한 최근의 흡착제 활용 연구의 상당 수가 이러한 3가지 계열에 포함되기 때문이다. 또한 이러한 적정기술의 발전 과정을 정리함으로써 향후 기술개발 방향을 설정하는데 도움을 주고자 하였다. 비소의 형태 및 기타 환경인자에 따라 흡착제의 흡착효율이 크게 달라지기 때문에 적절한 흡착제의 선택은 상당히 까다로운 결정과정을 가진다. 이런 의미에서 본 논문은 향후 비소제거를 위한 흡착제 선택 및 연구 방향 설정, 그리고 실험 연구에 필요한 기초적 배경 지식 전달에 도움을 줄 수 있을 것으로 판단된다. In this study, appropriate technologies for adsorptive removal of arsenic are classified and summarized based upon the basic adsorbent materials-industrial by-products, metal-based materials, and activated carbons. A lot of recent research papers deal with these three kinds of basic materials for adsorptive removal of arsenic from water and wastewater. Historical progress for developing arsenic adsorbent is also introduced in order to give helpful information for future study. Selection of appropriate adsorbent is very difficult because adsorption efficiency is highly dependent on arsenic oxidation state and the other environmental conditions. In this point of view, this paper may give a helpful information to choice an adsorbent for arsenic removal, to make good research plan and to understand basic knowledge.

제4주제 : 세계측지계 적용에 따른 RFID활용에 관한 연구

천현철(Cheon Hyun-Chul) 한국지적정보학회 2006 한국지적정보학회 학술발표대회 논문집 Vol.- No.-

Safety of One-Day Admission Transradial Coronary Intervention

오혜림,권현철,이선미,김용훈,천일석,천우정,최진호,이상철,성지동,김준수,전은석,김덕경,이상훈,홍경표,박정의,서정돈 대한심장학회 2004 Korean Circulation Journal Vol.34 No.7

Background:Recent advances of percutaneous coronary intervention (PCI) and transradial coronary intervention(TRI) have made it possible to reduce the local complication rate and the time until a return to ambulation.The aim of this study is to assess the safety and the patient satisfaction of the TRI-based one-day admissionprogram for PCI. Methods:Total 230 consecutive patients underwent TRI on the day of admission, according topre-determined inclusion criteria, from May 2001 to October 2003. The subjects were examined for clinical andangiographic characteristics. The patients having a same-day discharge were telephone-interviewed one day andseven days after discharge to assess late complications and the patients' satisfaction. Results:The mean age ofthe subjects was 59±9 years and 77.4% were male patients. 169 (73.4%) had stable angina and 37 (16.1%) hadunstable angina. Stents were implanted in 178 cases (69.3%). Of the 230 patients who underwent TRI, 206 patients(89.6%) could discharge on the same day after the procedure. The procedure was successful in 98.5%. The averagehospital stay for them was 9.4±1.4 hours. Two subjects reported hematoma near the puncture site within 24hours after discharge, and one reported this problem 7 days after discharge. During the follow-up, there wereno cases reporting chest pain needing rehospitalization or such complications as subacute vessel closure. Nodeaths, myocardial infarctions or revascularization were noted during the follow-up period. The majority ofthe patients (n=197, 95.6%) were satisfied with the same-day admission and discharge. Conclusions:Samedayadmission and discharge after TRI seems to be safe as well as satisfactory for not low-risk patients.

The Feasibility of 5-French Transradial Coronary Intervention, as Compared with a 6-French Approach, for Treating Chronic Total Occlusion

유철웅,권현철,천우정,최유정,김용훈,최진호,이상철,이상훈,홍경표,박정의 대한심장학회 2007 Korean Circulation Journal Vol.37 No.7

Background and Objectives:Recent studies have shown that transradial coronary intervention (TRI) is feasible for percutaneous revascularization of chronic total occlusion (CTO). We investigated the feasibility and safety of using a 5-French catheter (5F) TRI for CTO and we compared it with that of using a 6F catheter TRI. Subjects and Methods:One hundred fifteen patients (117 lesions) who underwent TRI for CTO (TIMI 0 or 1 for more than 2 months) were prospectively registered in this study from April 2002 to July 2004 (54 patients for the 5F and 61 patients for the 6F). The clinical, angiographic and procedural characteristics were evaluated and compared between the 2 groups. Results:No major difference was noted for the clinical characteristics between the 2 groups. Coronary angiography showed a shorter occlusion length (5F: 8.8±7.6 mm, 6F: 14.7±12.7, p=0.008) and a higher incidence of the tapered type of entry morphology (5F: 74%, 6F: 56%, p=0.042) in the 5F group. A deep-seating technique was used more often in the 5F group (5F: 83%, 6F: 51%, p<0.001). The procedural success rate was similar between the 2 groups (5F: 82%, 6F: 86%, p<0.54). The most common cause of procedural failure for both groups was failure to pass the guidewire. The occlusion duration, lesion length and lesion angulation were the statistically significant predictors of procedural failure. No major procedural or local complication was noted. Minor hematoma occurred in 2 patients and no radial artery occlusion was noted. Conclusion:A 5F catheter TRI may be feasible and safe to use for a selected group of CTO lesions. (Korean Circulation J 2007;37:298-303)

가토의 생체내에서 양막위에 배양된 자가 각막윤부상피세포의 특성

박정민,우정민,천현철,정우진,박우찬 대한안과학회 2006 대한안과학회지 Vol.47 No.10

Purpose: To investigate the characteristics of the limbal epithelial cells auto-cultivated in vivo on amniotic membrane (LIVAMs) designed for the treatment of limbal stem cell deficiency. Methods: We removed the epithelium of AM with a No.15 blade after it was blotted with 20% ethanol and made a 360˚stromal flap along the epithelial defect. We then mounted over-sized AM (1 mm larger in diameter than the defect) over the defect with the border of AM inserted under the flap, and performed interrupted suture with 10-0 nylon. A therapeutic contact lens was fitted over the AM and a temporary tarsorrhaphy was performed. To examine whether the limbal epithelial cells grew well onto AM, we observed the cornea after fluorescein dye staining using a slit lamp. To explore the characteristics of LIVAMs, we performed hematoxylin-eosin (H&E) staining, immunochemical staining with AK-2, AE-5, AM-3 monoclonal antibodies, and transmission electron microscopy. Results: Three of four rabbits had successful epithelial growth on the amniotic membrane. The epithelial growth on the amniotic membrane was stained using immunohistochemical staining (AK-2, AE-5). Electron microscopy showed a structure similar to that of a normal corneal epithelium. Conclusions: The technique of auto-cultivation of limbal epithelial cells in vivo on amniotic membrane can be an efficient and convenient method and preserves the characteristics of limbal epithelial cells for the treatment of limbal stem cell deficiency.