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

단안 분지망막정맥폐쇄 환자의 무증상 반대안에서 안구관류압의 일중변동

박창현,박혜영,윤재윤,박찬기,Chang Hyun Park,Hae Young Park,Jae Yoon Yoon,Chan Kee Park 대한안과학회 2014 대한안과학회지 Vol.55 No.2

Purpose: To investigate diurnal change in blood pressure (BP), intraocular pressure (IOP), and ocular perfusion pressure (OPP) in patients with unilateral branch retinal vein occlusion (BRVO) and compare the results with healthy controls. Methods: We conducted a prospective case‐control study which included 50 patients with unilateral BRVO and 50 agematched volunteers as controls. Each participant underwent a comprehensive ophthalmic examination including optical coherence tomography (OCT). BP and IOP were evaluated 4 times daily at 8 AM, 10 AM, 2 PM and 6 PM. The mean and fluctuation of BP, IOP, mean arterial pressure (MAP), mean OPP (MOPP), and diastolic OPP (DOPP) were compared between fellow eyes of BRVO patients and normal control eyes. Results: The average retinal nerve fiber layer (RNFL) thickness was significantly reduced in the fellow eyes of BRVO patients compared to control eyes (p < 0.001). Mean IOP and IOP fluctuation did not differ, but BP fluctuation (systolic BP fluctuation, p = 0.045; diastolic BP fluctuation, p = 0.037) and MAP fluctuation (p = 0.011) were greater in the fellow eyes of BRVO patients compared to normal eyes. The mean MOPP and DOPP did not differ between groups, however, the fluctuation of MOPP (p < 0.001) and DOPP (p < 0.001) were significantly increased in the fellow eyes of BRVO patients. The mean and fluctuation of BP, MAP, MOPP and DOPP were associated with reduced average RNFL thickness in the fellow eyes of BRVO patients. Conclusions: These results suggest the fellow eyes of unilateral BRVO patients may be at risk of developing glaucomatous damage. J Korean Ophthalmol Soc 2014;55(2):237-246

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.

분산 감소 기법에 의한 몬테칼로 선량 계산 효율 평가

박창현,박성용,박달,Park, Chang-Hyun,Park, Sung-Yong,Park, Dal 한국의학물리학회 2003 의학물리 Vol.14 No.4

몬테칼로 계산은 다른 어떤 알고리즘보다 정확한 선량 계산 결과를 주지만 계산 시간이 오래 걸리는 단점이 있다. 본 연구에서는 Varian 600 C/D 선형가속기로부터지 6 MV 광자선에 대해 몬테칼로 계산을 사용하여 얻은 선량 분포가 측정에 의해 얻은 선량 분포와 2% 이내에서 서로 잘 일치하도록 하며 분산 감소 기법을 사용하여 계산 시간 단축 정도를 평가하였다. 그리고 연산 능력을 높여 계산 시간 단축 정도를 평가하여 분산 감소 기법을 사용한 경우와 연산 능력을 높인 경우 간에 계산 시간 단축 정도를 비교하였다. 몬테칼로 계산 코드로는 빔 모사를 위해 BEAMnrc 코드, 선량 계산을 위해 DOSXYZnrc 코트를 각각 사용하였는데 분산 감소 기법은 이 코드들에서 지원하는 방법들을 사용하였고 연산 능력을 높이는 방법으로는 컴퓨터 클러스터를 이용한 병렬 처리를 사용하였다. 비교 결과, 분산 감소 기법을 사용하여 계산 시간을 최대 1/25 이상 단축시킬 수 있었고 9대의 컴퓨터를 이용한 병렬 처리 결과 계산 시간을 1/9로 단축시킬 수 있었다. 계산 곁과의 정확성을 만족할 만한 수준으로 유지할 수 있다면 분산감소 기법을 포함한 간략화된 물리의 적용은 현 시점에서 몬테칼로 선량 계산 시간을 획기적으로 단축시킬 대안이 될 수 있다. The Monte Carlo calculation is the most accurate means of predicting radiation dose, but its accuracy is accompanied by an increase in the amount of time required to produce a statistically meaningful dose distribution. In this study, the effects on calculation time by introducing variance reduction techniques and increasing computing power, respectively, in the Monte Carlo dose calculation for a 6 MV photon beam from the Varian 600 C/D were estimated when maintaining accuracy of the Monte Carlo calculation results. The EGSnrc­based BEAMnrc code was used to simulate the beam and the EGSnrc­based DOSXYZnrc code to calculate dose distributions. Variance reduction techniques in the codes were used to describe reduced­physics, and a computer cluster consisting of ten PCs was built to execute parallel computing. As a result, time was more reduced by the use of variance reduction techniques than that by the increase of computing power. Because the use of the Monte Carlo dose calculation in clinical practice is yet limited by reducing the computational time only through improvements in computing power, introduction of reduced­physics into the Monte Carlo calculation is inevitable at this point. Therefore, a more active investigation of existing or new reduced­physics approaches is required.

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.

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.

Cyclosporin A를 투여한 랫드 간장의 미세구조적 연구; 담세관을 중심으로

박창현,김윤정,장병준,임창형,윤화중,이덕윤,Park, Chang-hyun,Kim, Yun-jeong,Jang, Byung-joon,Lim, Chang-hyeong,Yoon, Hwa-joong,Lee, Duck-yoon 대한수의학회 1995 大韓獸醫學會誌 Vol.35 No.4

Cyclosporin A extracted from fungus Trichoderma polysporum Rifai and Cyclindrocarpon lucidum Booth serves as an important immunosuppressive drug in transplantation surgery. Systemic treatment with cyclosporin A induces an impairment of the biliary excretion of the bile salts and cholestasis. This study was designed to observe the Ultrastural changes of the hepatocytes and the bile canaliculi in cyclosporin A-induced intrahepatic cholestasis in rats. Cyclosporin A was injected into male Wistar rats intraperitoneally 50mg per kg body weight and rats were necropsied at 1, 3, 6, 9, 12, 24 hours. The liver tissues were observed with transmission and scanning electron microscopes and the results were as follows. Transmission electron microscopy: After cyclosporin A injection, SER and lysosomes were increased in the hepatocytes until 9 hours. At 12 hours after injection of cyclosporin A, RER with dilated cistern were increased, and SER, lysosomes in the cytoplasm were decreased. From 1 hour to 24 hours after injection of cyclosporin A, there were dilation of bile canalliculi and decreased or lost microvilli. At 24 hours the dilation of bile canaliculi were decreased. Scanning electron microsocopy: After cyclosporin A injection, the bile canaliculi were dilated and the microvilli were shortened, decreased or lost according to the sites. At 24 hours, the microvilli packing the bile canaliculi were observed. These observations suggest that cyclosporin A-induced cholestasis is associated with the dilation of bile canaliculi, increased microfilaments of the pericanalicular region and decreased or lost microvilli.

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.

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.

인지 및 행동영역에서 교대 근무의 유해적인 영향 : 비판적 고찰

이수지,박창현,하은지,박신원,홍혜진,박수현,마지영,강일향,강한,송병훈,김정윤,김지은,Lee, Suji L.,Park, Chang-hyun,Ha, Eunji,Park, Shinwon,Hong, Haejin,Park, Su Hyun,Ma, Jiyoung,Kang, Ilhyang,Kang, Hahn,Song, William Byunghoon,Kim, Jungyo 대한생물정신의학회 2017 생물정신의학 Vol.24 No.2

Shift workers experience a disruption in the circadian sleep-wake rhythm, which brings upon adverse health effects such as fatigue, insomnia and decreased sleep quality. Moreover, shift work has deleterious effects on both work productivity and safety. In this review, we present a brief overview of the current literature on the consequences of shift work, especially focusing on attention-associated cognitive decline and related behavioral changes. We searched two electronic databases, PubMed and RISS, using key search terms related to cognitive domains, deleterious effects, and shift work. Twenty studies were eligible for the final review. The consequences of shift work can be classified into the following three categories extracted from the literature review : 1) work accidents ; 2) commuting accidents such as car accidents that occur on the way to and from work ; and 3) attendance management at work (i.e., absenteeism, tardiness, and unscheduled early departure). These cognitive and behavioral consequences of shift work were also found to be associated with sleep disorders in shift workers. Thus, improvements in the shift work system are necessary in order to enhance workers' health conditions, work productivity, and safety.