녹내장 환자에서 유리체강 내 베바시주맙 주사가 망막신경섬유층에 미치는 영향

박창현,이기일,박혜영,이진해,김인태,박찬기,Chang Hyun Park,Kee Il Lee,Hae Young Park,Jin Hae Lee,In Tae Kim,Chan Kee Park 대한안과학회 2014 대한안과학회지 Vol.55 No.5

Purpose: To examine retinal nerve fiber layer (RNFL) changes after intravitreal injection of bevacizumab in patients with or without underlying glaucoma. Methods: A total of 104 eyes of 104 patients with retinal disease undergoing intravitreal injection of bevacizumab were prospectively investigated. Bevacizumab injections (1.25/0.05 mg/mL) were performed using a standardized technique. In the patient who had pretreatment with intraocular pressure (IOP)-lowering medication, 1 drop of brimonidine was instilled 30 minutes before the injection. Before and after the intravitreal injections, the patients were monitored for IOP and evaluated with optical coherence tomography using Stratus at least 3 months after the injection. Results: Thirty minutes after injection, 6.4% of patients had an IOP over 30 mm Hg in the non-pretreatment group while no patient had an IOP over 30 mm Hg in the pretreatment group. In eyes with only retinal diseases, the RNFL thickness did not change significantly after the injection regardless of pretreatment, whereas in eyes with underlying glaucomatous damage and no pretreatment, significant decrease in RNFL thickness was observed at the superior (<em>p</em> = 0.036) and temporal (<em>p</em> = 0.048) sectors of the optic nerve head without pretreatment. Conclusions: Intravitreal injection of bevacizumab did not typically cause significant changes in RNFL thickness; however, in eyes with underlying glaucoma without pretreatment, a significant decrease in RNFL thickness was observed in the superior and temporal sectors of the optic nerve head. Therefore, applying IOP-lowering pretreatment medication before intravitreal injection of bevacizumab is required for protection of RNFL in glaucoma patients. J Korean Ophthalmol Soc 2014;55(5):693-701

홍화(Carthamus tinctorius L.)씨 분말의 랫드 골절에 대한 치유 효과

박창현,엄창섭,배춘식,Park, Chang-Hyun,Uhm, Chang-Sub,Bae, Chun-Sik 한국현미경학회 2001 Applied microscopy Vol.31 No.4

12주령 랫드의 비골의 골절을 유발한 후 골절치유에 미치는 홍화씨 분말의 영향을 알아보고자 실험을 실시한 결과 다음과 같은 결과를 얻었다. 비골의 골절은 골절유발 후 5주에 성숙된 신생골 조직으로 충만되어 조직형태학적으로 완전한 유합이 이루어지는데, 홍화씨 분말을 투여한 결과 골절유발 후 4주에 성숙된 신생골 조직으로 골절단이 충만되어 완전한 유합을 이룬 후 5주에서는 골수강도 개통되는 등 대조군과 비교하여 유합시기를 기준으로 1.5주 정도의 빠른 골절의 치유가 이루어졌다. 이상의 결과는 홍화씨 분말에 골절의 치유를 촉진시키는 성분이 포함되어 있을 가능성을 시사한다고 사료된다. Safflower (Carthamus tinctorius L.) is a thistle-like annual plant mainly grown in dry hot climates as an oilseed or birdseed. Traditionally, the oil has mainly been sold in the health food market because it is unsaturated having high linoleic and oleic acid levels. With increased health consciousness in recent years, the oil quality has become a more general health issue. This study was designed to understand whether safflower seed powder has positive effects on the fracture healing in rats. Simple transverse fracture of rat fibula was made with a rotating diamond disc saw. The histologic changes of rats were observed with a scanning electron microscope. The fractured fibulae showed a complete fusion at the fracture site in the 4th to 5th week after a simple transverse fracture. Administration of safflower seed powder facilitated the speed of histologic changes without affecting qualitative changes. These results suggest that safflower seed powder nay have substances that help the fracture healing process.

생물시료의 전자현미경 시료 제작 및 관찰 과정에서 발생되는 인공물

박창현,조강용,엄창섭,Park, Chang-Hyun,Cho, Kang-Yong,Uhm, Chang-Sub 한국현미경학회 2005 Applied microscopy Vol.35 No.1

전자현미경 관찰에 있어서 최종적인 목표는 정확한 정보를 포함하는 좋은 사진을 얻는 것이라 할 수 있다. 이를 위하여는 사진에 인공물이 포함되지 않도록 표본의 채취, 처리, 관찰 및 사진 작업 등 모든 단계에서 주의를 기울여야 한다. 본 고에서는 통상적인 전자현미경 관찰을 위한 시료의 채취로부터 사진의 현상, 인화에 이르는 여러 단계에서 발생될 수 있는 인공물들과 그 원인을 살펴 보고 해결책을 제시함으로써 전자현미경 관찰을 위한 표본의 올바른 제작과 미세구조의 해석에 도움을 주고자 하였다. Fine photographs are essential in the electron microscopy. Artifacts can be introduced during all steps of electron microscopy; specimen processing, observation and printing. Every caution is necessary to avoid the artifact formation. In this review, the authors discussed the causes of various artifacts and suggested the solution to help the correct tissue handling and electron microscopic observations.

국내 발전기업의 아시아 화력발전플랜트 시장 진출전략

박창현,문승재,Park, Chang-Hyun,Moon, Seung-Jae 한국플랜트학회 2011 플랜트 저널 Vol.7 No.4

The power plant companies reached the culmination for growth in the domestic market. Besides, we have faced many challenges such as an electricity opening market trend for overseas, banning the use of coal due to the United nations framework convention on climate change, and the meticulous attention regarding the government's electricity charge plan. On the other hand, the overseas business has been a critical issue since China and many other developing countries expanded their projects abroad. Another factor is that power plant industry is being privatized, and it made the market regulation a bit loose. Thus, the market environment became favorable toward those companies which planned many overseas businesses. In this research, the power plant company's current condition for construction and operation as well as its technical competitiveness were analyzed, and an alternative plan using SWOT analysis for entering an oversea market was made. It dealt with both internal and external factors. Also, examined was the current situation under the power plant industry dealing with restructure for electric industry, lack of fossil fuel, and the United nations framework convention on climate change. From the research, it was suggested that many successful strategies to enter the overseas business by using the market trend I researched.

산소로 유도된 망막증 모델에서 인간재조합 적혈구생성인자가 망막혈관에 미치는 영향

박창현,박태관,김성신,이승준,온영훈,김성운,Chang Hyun Park,Tae Kwann Park,Seung Joon Lee,Young Hoon Ohn,Sung Woon Kim 대한안과학회 2007 대한안과학회지 Vol.48 No.6

Purpose: To evaluate the effect of recombinant human erythropoietin (rhEPO) on the retinal vessels in a rat model of oxygen-induced retinopathy (OIR). Methods: Twenty-six Sprague-Dawley rat siblings were exposed to seven cycles each of hyperoxia (80% O2, 23.5 hours) and room air recovery (0.5 hours), followed by exposure to room air for five days. After each of the test group and control group was divided into two groups of rhEPO injected group and normal saline injected group, 400 u/kg of rhEPO or normal saline were intraperitoneally injected, respectively on the third, fifth, and eighth days of the experiment. Retinal neovascularization and capillary densities were compared between the rats on the eighth and fourteenth day after injection. The extent of VEGF164, and IGF-1 mRNA expression was measured in the rats on the 14th day post-injection. Results: Neovascularization and capillary density was the most increased in the rhEPO injected test group, but the avascular area was widely distributed in the vicinity of the retina. The degree of VEGF164 mRNA expression was highest in the test group that had been injected with normal saline. We found no difference in IGF-1 mRNA levels between the groups. Conclusions: We can infer that rhEPO can be a potent factor for inducing retinal neovascularization.

열공망막박리에서 냉동고정술과 도상검안경레이저광응고술의 결과 비교

박창현,박성희,이성진,Chang Hyun Park,M,D,Song Hee Park,M,D,Ph,D,Sung Jin Lee,M,D,Ph,D 대한안과학회 2008 대한안과학회지 Vol.49 No.11

Purpose: To compare the efficacy and safety of intraoperative laser indirect ophthalmoscopy and cryopexy for rhegmatogenous retinal detachment through the use. Methods: We retrospectively analyze the clinical results of 60 patients (61 eyes) with rhegmatogenous retinal detachment. All eyes had an attached macula and were scheduled for conventional scleral buckling surgery with cryopexy (25 eyes) or laser indirect ophthalmoscopy (36 eyes) from March 2001 to August 2007. The visual acuities of the two groups at the first postoperative day, 1 week, 1 month, and 3 months were compared. Retinal reattachment, macular pucker, cystoid macular edema, and proliferative vitreoretinopathy were confirmed 3 months after surgery. Results: The visual recovery was faster in patients who received laser indirect ophthalmoscopy (1 day, P=0.044; 1 week, P=0.017). During the follow-up period, anatomical failure in the laser indirect ophthalmoscopy group did not develop, but there were two anatomical failures in the cryopexy group. In addition, 1 PVR was detected in the cryopexy group. However, neither group exhibited macular pucker or cystoid macular edema. Postoperative additional laser photocoagulation was performed on 7 eyes (19.4%) in thelaser indirect ophthalmoscopy group and 2 eyes (4.0%) in the cryopexy group. Conclusions: Although intraoperative laser indirect ophthalmoscopy causes less chorioretinal scar formation than cryopexy, it has a higher anatomical success rate and allows for faster visual recovery. J Korean Ophthalmol Soc 2008;49(11):1779-1784

기아 마우스 담세관의 전자현미경적 연구

박창현,신영철,장병준,Park, Chang-Hyun,Shin, Young-Chul,Jang, Byung-Joon 한국현미경학회 1996 Applied microscopy Vol.26 No.2

This study was designed to investigate the ultrastructural alterations of the hepatocyte and bile canaliculus of the fasted mice with transmission and scanning electron microscopes. The morphometry was also carried out for the caliber of the bile canaliculus and the number, length and thickness of the microvillus. The hepatocyte observed in the three day fasting group showed ultrastructural images of active function. The dilated bile canaliculi, especially of type II were increased in number as compared with those seen in the normal group. However, the hepatocyte observed in the six day fasting group showed ultrastructural images of inactive function. The bile canaliculi without dilation (type I) were increased in number. The number of microvilli were identical with one another among the different types of bile canaliculi, while their length and thickness were reduced in the dilated bile canaliculi. From the evidence, the luminal size of the bile canaliculi seems to be easily changeable according to the functional state of the hepatocyte. However, the microvilli may not be changed in number but may be changed length and thickness when the bile canaliculi are dilated.

Correlation 분석 기법을 적용한 요통 환자에 관한 레지스트리 데이터의 탐색적 분석

박창현,박무순,김형석,차윤엽,김순중,고연석,오민석,황의형,신병철,김창업,송윤경,Park, Chang-Hyun,Park, Mu-Sun,Kim, Hyung-Suk,Cha, Yun-Yeop,Kim, Soon-Joong,Ko, Youn-Suk,Oh, Min-Seok,Hwang, Eui-Hyoung,Shin, Byung-Cheul,Kim, Chang-Eop,Song 한방재활의학과학회 2017 한방재활의학과학회지 Vol.27 No.4

Objectives The aim of this study is to analyze the patients who have low back pain through registry. Methods We registered patients with low back pain who visited department of korean rehabilitation medicine in university hospitals on study. We collected data from 116 subjects consisted of 51 inpatients and 65 outpatients and ruled out 8 who didn't have pattern identification data at the point of inpatient or outpatient visit so we analyzed 108 in total. We used Pearson's product moment correlation to find correlationship among variables, and analyzed statistical data using Phyton scipy library stats package. Results We set general features, region of the pain, physical examination, ROM, questionnaire results, pattern identification as variables and draw a conclusion by analyzing these variables. Conclusions Registry aimed at low back pain patients was established in department of korean rehabilitation medicine of university hospitals and exploratory analysis based on data were made. Through the registry, we expect that more advanced studies will be performed; for example, executing research which verifies effectiveness and stability of korean medical treatment or developing tools to fill the gap between pattern identification and disease identification.

흰쥐에서 분리 배양한 간세포의 담세관 형성에 있어서 액틴미세섬유의 역할에 관한 전자현미경적 연구

박창현,장병준,엄창섭,Park, Chang-Hyun,Chang, Byung-Joon,Uhm, Chang-Sub 한국현미경학회 1999 Applied microscopy Vol.29 No.4

간세포의 기능적 연구를 위한 배양계를 확립하기 위하여 Sprague-Dawley계 흰쥐의 간장에서 collagenase와 hyaluronidase의 혼합액을 이용하여 간세포를 분리하고 배양하여, 배양중인 간세포의 구조적인 변화와 담세관의 형성 과정을 확인하고, cytochalasin D를 배양계에 첨가한 경우 발생되는 간세포 및 담세관의 구조적인 변화를 살펴보아 다음과 같은 결과를 얻었다. 분리 배양한 흰쥐의 간세포는 원형이었고, 표면에 미세융모를 가지고 있었으며. 배양중 서로 부착되어 세포띠를 형성하였다. Cytochalasin D처리후 간세포의 표면은 미세융모가 소실되어 편평하게 변화되었으며, 소포성 돌출물이 자주 관찰되었다. 담세관은 부착된 간세포의 사이에서 형성되었으며, 간세포 표면의 작은 융기에서 기시하는 다양한 길이 및 형태의 미세융모로 채워져 있었고, 양단에는 치밀결합 및 부착만 등으로 구성된 연접복합체가 존재하였다. Cytochalasin D 처리후 당세관의 내강은 팽창되었으며 미세융모는 소실되어 거의 존재하지 많았고, 양단에 존재하는 연접복합체는 파괴되어 간격이 벌어진 곳이 많았다. 담세관내에 존재하는 미세융모 속에 존재하는 액틴미세섬유심은 완전하게 형성되어 있는 경우, 불완전하게 적은 양만 존재하는 경우, 그리고 전혀 존재하지 않는 경우가 있었다. 담세관주변세포질에 존재하는 액틴미세섬유얼기의 형성은 불완전하여 부위에 따라 없는 곳도 있었다. Cytochalasin D처리후 담세관주변세포질의 액면미세섬유얼기는 존재하지 많았다. 이상의 결과로 흰쥐의 간장에서 분리한 간세포는 배양중 성장하면서 정상적인 담세관을 형성함을 알 수 있었으며, 담세관의 형성은 접착부위의 연접복합체의 형성 및 미세융모의 형성,담세관 내 액틴미세섬유심 및 담세관주변세포질내 액틴미세섬유얼기의 형성 등을 특정으로 하는 것으로 판단된다. Bile canaliculi are the structure delivering bile secreted by hepatocytes into the bile passage. Bile secretion is mainly controlled by the cytoskeletal elements, mainly of actin in the microvilli, pericanalicular web. Most studies on the bile secretion have been done in viva situation, however, to control the various parameters in vitro culture system seem to be more useful. To set up an in vitro experimental system, the investigator isolated hepatocytes with an enzymatic method using a mixture of collagenase and hyaluronidase from normal Sprague-Dawley rat liver and cultured. Isolated hepatocytes were round and formed cords in culture. Microvilli covered the whole surface of hepatocytes. Bile canaliculi were formed between hepatocytes and were characterized by the presence of microvilli of various lengths and shapes mainly arising from small surface mounds. Actin filament core in the microvilli and pericanalicular actin web were incomplete. After cytochalasin D treatment, cultured hepatocytes were round but the surface were irregular with surfacen blebs, folds and grooves. Microvilli on the surface were scarce. Bile canaliculi were markedly dilated often with the detached junctional complexes. Bile canaliculi lacks microvilli almost completely and extended into the pericanalirular cytoplasm showing complex vacuolar and tubular structures by transmission electron mciroscopy. Pericanalicular actin web, intermediate filaments were hardly identified. Subsurface actin filaments were scattered scarcely under the cell membranes. These results suggest that hepatocytes isolated from rats can survive and form bile canaliculi in culture and the actin filaments are involved in the formation and/or maintenance of the bile canaliculi.

근사최적화 기법을 이용한 RC 빌딩의 구조 최적설계

박창현,안희재,최동훈,정철규,Park, Chang-Hyun,Ahn, Hee-Jae,Choi, Dong-Hoon,Jung, Cheul-Kyu 한국전산구조공학회 2011 한국전산구조공학회논문집 Vol.24 No.2

본 논문에서는 수직하중, 풍하중 및 지진하중에 의해 발생하는 변위 관련 구속조건을 만족하면서 RC(Reinforced Concrete) 빌딩 구조의 부피를 최소화하기 위한 설계문제를 정식화하였다. 구조해석 절차 자동화의 어려움으로 인해 실험 계획법과 근사화기법, 최적화기법을 이용한 근사모델기반 최적설계를 수행하였다. 특히, 만족할 만한 설계 결과를 얻을 때까지 설계변수의 범위와 구속조건의 허용값을 조정하는 단계적 최적설계 방법을 제안하였다. 제안된 단계적 최적설계 방법을 통해 주어진 구속조건을 모두 만족하면서 RC 빌딩 구조의 부피를 초기 설계 대비 53.3% 감소시키는 결과를 얻음으로 써 본 논문에서 보인 단계적 최적설계 방법의 타당성을 보였다. A design optimization problem was formulated to minimize the volume of an RC building structure while satisfying design constraints on structural displacements under vertical, wind and seismic loads. We employed metamodel-based design optimization using design of experiments, metamodeling and optimization algorithm to circumvent the difficulty of the automation of structural analysis procedure. Especially, we proposed a design approach of repetitive design optimizations by stages with changing the side constraint values on design variables and limit values on design constraints until a satisfactory design result was obtained. Using the proposed design approach, the volume of the RC building structure has been reduced by 53.3 % compared to the initial one while satisfying all the design constraints. This design result clearly shows the validity of the proposed design approach.