주파수 변화 추정 알고리즘 비교분석 (pp.1233-1234)

김철훈(Chul-Hun Kim),강상희(Sang-Hee Kang),남순열(Soon-Ryul Nam),김수환(Su-Whoan Kim) 대한전기학회 2006 대한전기학회 학술대회 논문집 Vol.2006 No.7

Reliable frequency estimation is important for active power control, load shedding and generator protection. Thereby, frequency estimation is researched and some algorithms is proposed. This paper analyzed strength and weakness of each algorithms through comparative analysis of frequency estimation. Used algorithms are Zero Crossing detection, Discrete Fourier Transformation, Least Error Squares.

서울지역 길고양이의 Toxoplasma 감염증 실태조사

김능희 ( Neung Hee Kim ),채희선 ( Hee Sun Chae ),한혜진 ( Hye Jin Han ),손홍락 ( Hong Rak Son ),김창기 ( Chang Ki Kim ),김선흥 ( Sun Heung Kim ),이정학 ( Jung Hark Lee ),김철훈 ( Chul Hun Kim ) 한국가축위생학회 2009 韓國家畜衛生學會誌 Vol.32 No.3

Toxoplasma gondii is one of the most common protozoa parasites of human and other warm-blooded animals. Cats and wild felidae play crucial roles in the epidemiology of toxoplasmosis. This study was performed to survey the prevalence of T. gondii infection among stray cats in the Seoul. A total of 422 stray cat blood samples were collected from Seoul area. Positive sera for T. gondii were identified in 56 samples (13.3%) exclusively via the latex agglutination test and the detection no antigen particles among seropositive samples by PCR. The overall infection rate of male stray cats (14.4%) presented as higher than that of female cats (10.7%). This study suggested that T. gondii is widespread in stray cats of Seoul area. It is needed to control urban stray cat population and to reduced the risk of zoonotic transmission of toxolasmosis to other animals and humans.

서울지역의 개와 고양이에서 분리한 Staphylococcus aureus의 항생제 감수성 및 multiplex PCR을 이용한 장독소의 검출

김능희 ( Neung Hee Kim ),채희선 ( Hee Sun Chae ),손홍락 ( Hong Rak Son ),김창기 ( Chang Ki Kim ),김선흥 ( Sun Heung Kim ),이정학 ( Jung Hark Lee ),김철훈 ( Chul Hun Kim ) 한국가축위생학회 2010 韓國家畜衛生學會誌 Vol.33 No.3

The antimicrobial susceptibility of 73 strains of Staphylococcus aureus isolated from dogs and cats was determined against 16 antimicrobial agents. All isolates were susceptible to cephalothin (CF), vancomycin (VA), rifampin (RA), quinupristin-dalfopristin (SYN) and linezolid (LZD), whereas more than 86.3% of the isolates were resistant to penicillin (P). In the case of enterotoxin production, 8.2% of 73 strains produced enterotoxin A and 1 strain produced enterotoxin C. Appropriate protocols for antimicrobial agents and strategies to reduce antimicrobial resistance will need to be investigated in the future.

당뇨 유도 백서 경골에 매식한 티타늄 임플란트 주위에 지방조직 유래 줄기세포 적용 시 골치유에 미치는 영향

김민구(Min-Gu Kim),정인교(In-Kyo Jung),신상훈(Sang-Hun Shin),김철훈(Chul-Hoon Kim),김복주(Bok-Joo Kim),김정한(Jung-Han Kim),황영섭(Young-Sup Hwang),정유진(Eu-Gene Jung),김진우(Jin-Woo Kim),김욱규(Uk-Kyu Kim) 대한구강악안면외과학회 2010 대한구강악안면외과학회지 Vol.36 No.5

Introduction: Diabetes mellitus, as a major health problem for the elderly has been shown to alter the properties of the bone and impair bone healing around a titanium implant in both humans and animals. The aim of this study was to examine the effect of adipose-derived stem cells on the healing process around a titanium implant in streptozotocin-induced diabetic rats. Materials and Methods: Thirteen rats were divided into two groups: adipose-derived stem cells injected group and a control group. A titanium screw implant (diameter: 2.0 mm, length: 3.5 mm) was placed into both tibia of 13 rats: 13 right tibia as the control group and 13 left tibia as the experimental group. The rats were sacrificed at different intervals (1, 2, and 4 weeks) after implantation for histopathology observations and immunohistochemistric analysis. Results: The histopathological findings revealed earlier new formed bone in the experimental group than the control group. In particular, at 1 week after implantation, the experimental group showed more newly formed bone and collagen around the implant than the control group. In immunohistochemistric analysis, osteoprotegerin (OPG) expression in the experimental group increased early compared to that of the control group until 2 weeks after implantation. However, after 2 weeks, OPG expression in the experimental group was similar to OPG expression in the control group. The receptor activator of nuclear factor κB ligand (RANKL) expression in the experimental group increased early compared to that of the control group, and then decreased at 2 weeks. After 2 weeks, the level of RANKL expression was similar in both groups. Conclusion: These results suggest that adipose-derived stem cells in implantation can promote bone healing around titanium, particularly in diabetes mellitus induced animals.

가토의 측두하악관절원판 결손에서 간세포 성장인자가 치유에 미치는 영향

김복주,성화식,김철훈,김규천,황희성,신상훈,Kim, Bok-Joo,Seong, Hwa-Sik,Kim, Chul-Hoon,Kim, Gyoo-Cheon,Hwang, Hee-Sung,Shin, Sang-Hun 대한악안면성형재건외과학회 2009 Maxillofacial Plastic Reconstructive Surgery Vol.31 No.1

Purpose: The purpose of this study is to investigate the therapeutic use of Hepatocyte growth factor(Adv.CMV.HGF) in temporomandibular joint disc defect. Materials and methods: Twelve New Zealand white rabbits, weighing 2.5 - 3.0 kg, were used in this experiment. Defects(2 mm in diameter) were created in their TMJ discs. Recombinant Adv.CMV.HGF with gelatin sponge($Gelfoam^{(R)}$) as carrier was implanted in the defects. We divided the rabbits into four batches according to the duration of the implantation - of 1, 4, 8, 12 weeks - and both left and right TMJ of each rabbit in all groups were used in the research : left joints were used as experiment group and right were control group. Each batch of rabbits was killed one, four, eight and twelve weeks after the experimentation respectively, and called Group A, B, C, and D. (Group A = 1 wk, B = 4 wks, C = 8 wks, and D = 12 wks) Results: The experimental group showed a significant increase in the number of chondroblasts and active cell differentiation at the margin of the defects. Compared to the control group, in the experiment group chondroblasts increased and chondrocytes showed a columnar arrangement, which is witnessed at the time of cell differentiation. Conclusion: This study supports the case that Avd.CMV.HGF may be useful in the repair of articular disc of the rabbit TMJ.

Chios Gum Mastic Induces Cell Cycle Arrest and Apoptosis in YD9 Human Oral Squamous Carcinoma Cells

Jae-Hyoun Park(박재현),Gyoo-Cheon Kim(김규천),Hyun-Ho Kwak(곽현호),In-Ryoung Kim(김인령),Seung-Eun Lee(이승은),Jin Chung(정진),Hae-Ryoun Park(박혜련),Sang-Hun Shin(신상훈),Soo-Hyun Choi(조수현),Chul-Hoon Kim(김철훈),Chang-Ok Nam( 대한체질인류학회 2008 대한체질인류학회지 Vol.21 No.1

식물인 Pistiacia lentiscus L. var. Chia.는 그리이스 키오스 섬의 남부지방에서만 서식하며, Chios gum mastic (CGM)으로 알려져 있는 수지를 만들어 낸다. Pistacia lentiscus 나무의 줄기와 잎에서 추출한 천연물질인 CGM은 과거 수세기 동안 지중해와 중동 지역 국가들에서 음식 첨가물과 치료약으로 광범히 하게 사용되어 왔었다. 본 연구는 사람구강편평상피암종세포(YD9 cells)에서 CGM의 세포독성과 성장억제 효과, 그리고 세포주기의 변형과 세포자멸사(apoptosis)에 대한 분자생물학적 기전을 알기 위해서 수행하였다. YD9 세포와 사람정상각화세포(HaCaT)의 생존률 측정은 MTT법을 시행하였고, YD9 세포의 성장억제를 확인하기 위해서는 clonogenic assay를 사용하였다. 세포자멸사가 유도되는 YD9 세포를 관찰하기 위해서 hoechst 염색법과 DNA 전기영동법을 사용하였다. 그리고 YD9 세포에 CGM을 적용한 후, Western blot 분석, 세포면역화학염색, 공점레이저주사현미경 검경, FACScan flow cytometry, 사립체막 전위변화, proteasome 활성도 측정 등을 시행하였다. CGM으로 처리된 YD9 세포는 용량 의존적인 세포 성장억제와 세포자멸사에 의한 세포죽음을 보였고, caspase-9, caspase-3, PARP 그리고 DFF45 (ICAD)의 파괴와 분절의 생성, DNA의 조각남, 핵 응축, 사립체막전위의 감소, Bax와 Bcl-2의 분율의 변화, cytochrome c의 사립체에서의 세포질로의 유리, AIF와 DFF40 (CAD)의 핵으로의 이동과 같은 세포자멸사 증거를 보였다. Flow cytometry 분석에서는 cyclin D1, cyclin D3, Cdk2 그리고 Cdk4의 발현의 감소와 p21<SUP>WAF1/CIP1</SUP>와 p53의 발현 증가와 관계있는 것으로 보여지는 G1 세포주기 정지를 보였다. 이러한 결과는 CGM이 세포주기 관련 단백질들의 변형을 유도한 G1 세포주기정지와 사립체와 caspase 경로를 통한 세포자멸사를 유도함을 명확하게 증명하고 있다. 이와 같은 강력한 세포주기 정지와 세포자멸사 유도능은 CGM이 사람구강편평세포암종의 새로운 치료전략으로서의 가능성을 높여 준다고 생각한다. Chios gum mastic (CGM) is obtained from the stem and leaves of Pistacia lentiscus trees and has been extensively used for centuries in Mediterranean and Middle Eastern countries, both as a dietary supplement and herbal remedy. This study was undertaken to examine in vitro effects of cytotoxicity and growth inhibition, and the molecular mechanism underlying modulation of cell cycle and induction of apoptosis in YD9 human oral squamous carcinoma cell line treated with CGM. The viability of YD9 cells and human normal keratinocyes (HaCaT cells), and the growth inhibition of YD9 cells were assessed by the MTT assay and clonogenic assay respectively. The hoechst staining and DNA electrophoresis were conducted to observe the YD9 cells undergoing apoptosis. YD9 cells were treated with CGM, and Western blotting, immunocytochemistry, confocal microscopy and FACScan flow cytometry were conducted. Mitochondrial membrane potential change and proteasome activity were measured. CGM treatment on YD9 cells resulted in a does-dependent inhibition of cell growth and induced apoptotic cell death. And tested YD9 cells showed several lines of apoptotic manifestation. Flow cytometric analysis revealed that CGM resulted in G1 arrest in cell cycle progression which was associated with decrease in the protein expression of cyclin D1, cyclin D3, Cdk2 and Cdk4, and increase in the protein expression of p21<SUP>WAF1/CIP1</SUP> and p53. These results demonstrate that CGM induces G1 the cell cycle arrest via the modulation of cell cycle-related proteins, and apoptosis via mitochondria and caspase pathway in YD9 cells, suggesting that CGM can be considered as a novel therapeutic strategy for human oral squamous cell carcinoma from its strong cell cycle arrest and apoptosis-inducing activity.

Apoptotic Effect of Co-Treatment with a Natural Product, Chios Gum Mastic, and a Synthetic Chenodeoxycholic Acid Derivative, HS-1200, on Human Osteosarcoma Cells

Ji-Hak Min(민지학),Min-Jeong Kim(김민정),In-Ryoung Kim(김인령),Seung-Eun Lee(이승은),Hyun-Ho Kwak(곽현호),Gyoo-Cheon Kim(김규천),Hae-Ryoun Park(박혜련),Sang-Hun Shin(신상훈),Chul-Hoon Kim(김철훈),Na-Young Jeong(정나영),Hongsuk Suh 대한체질인류학회 2008 대한체질인류학회지 Vol.21 No.2

Chios gum mastic(CGM)은 그리이스 지역에서만 서식하는 Pistacia lenticulus 나무의 줄기와 잎에서 추출한 수지상의 천연 추출물이다. 합성 chenodeoxycholic acid(CDCA) 유E씨가 여러 가지 암세포에 유도한 세포자멸사 연구들이 보고되어져 왔다. 본 연구는 천연물질인 CGM과 항성 CDCA 유도체인 HS-1200의 병용처리가 사람골육종세포에 효과적인 상승 세포자멸사 효과가 있는지를 알기 위해서 수행되었다. CDM과 HS-1200의 병용처리가 단독처리에 비해서 효과적인 세포생존율 감소가 있는지 확인하기 위해서 MIT법을 시행하였고, 세포자멸사의 유도와 증가를 확인하기 위해서 Hoechst 염색법과 DNA 전기영동법을 사용하였다. 병용처리 때, 세포자멸사에 관계하는 단백질의 발현 변화와 세포내에서의 이동을 밝혀내기 위해서 Western bot 분석과 면역형광염색법을 수행하였다. 더 나아가서 proteasome 활성도와 사립체막 전위 변화를 측정하였다. 병용처리 된 사람골육종세포는 단독처리 된 사람골육종세포에서 거의 관찰할 수 없었던 많은 핵 응축, DNA 조각남, 사립체막 전위와 proteasome 활성도의 감소, DNA 양의 감소, cytochrome c의 세포질로의 유리, AIF와 DFF40(CAD)의 핵으로의 이동, caspase-7, caspase-3 그리고 PARP의 활성화와 같은 세포자멸사 증거를 보였다. 24시간 동안 40㎍/mL CGM과 25μM HS-1200을 각기 단독처리 한 결과에서는 세포자멸사를 유도 못했으나, 병용처리한 결과에는 아주 탁월한 세포자멸사의 유도를 보였다. 이러한 병용처리 결과는 사람골육종의 새로운 치료적 전략으로 응용될 수 있다고 생각한다. Chios gum mastic (CGM) is a resinous exudate obtained from the stem and the main leaves of Pistacia lenticulus tree native to Mediterranean areas. Recently it reported that CGM induced apoptosis in a few cancer cells in vitro. It has been reported that the synthetic chenodeoxycholic acid (CDCA) derivatives showed apoptosis-inducing activity on various cancer cells in vitro. This study was undertaken to investigate the synergistic apoptotic effect of co-treatment with a natural product, CGM and a CDCA derivative, HS-1200 on human osteosarcoma (HOS) cells. To investigate whether the co-treatment of CGM and HS-1200 compared with each single treatment efficiently reduced the viability of HDS cells, MTT assay was conducted. Induction and augmentation of apoptosis were confirmed by DNA electrophoresis, Hoechst staining and DNA hypoploidy, Westen blot analysis and immuno-fluorescent staining were performed to study the alterations of the expression level and translocation of apoptosis-related proteins in co-treatment. Furthermore, proteasome activity and mitochondrial membrane potential (MMP) change were also assayed. In this study, HOS cells co-treated with CGM and HS-1200 showed several lines of apoptotic manifestation whereas each single treated HOS cells did not. Although the single treatment of 40 ㎍/㎖, CGM or 25 μM HS-1200 for 24 h did not induce apoptosis, the co-treatment of them induced prominently apoptosis. Therefore our data provide the possibility that combination therapy of CGM and HS-1200 could be considered as a novel therapeutic strategy for human osteosarcoma.

가토의 하악관절에 Collagenase 주입을 통한 관절염 유발 모델에 관한 연구

송동석,김기현,이재열,정유진,안상욱,송진우,김철훈,신상훈,정인교,Song, Dong-Seok,Kim, Ki-Hyun,Lee, Jae-Yeol,Jung, Eu-Gene,Ahn, Sang-Wook,Song, Jin-Woo,Kim, Chul-Hun,Shin, Sang-Hun,Chung, In-Kyo 대한악안면성형재건외과학회 2010 Maxillofacial Plastic Reconstructive Surgery Vol.32 No.6

Purpose: The purpose of this study is to induce artificial arthritis on rabbit TMJ by injecting collagenase. Materials and Methods: An experimental animal model of arthritis induced by surgical method or intraarticular injection of chemical agent like LDH, papain, ketorolac. Surgical method is complex and needs a long time in inducing arthritis. Intra-articular injection of chemical agent like LDH, papain, ketorolac is simple. But chemical agent like LDH, papain, ketololac needs multiple injections to induce arthritis and mechanism inducing arthritis was known. Collagenase destroys helical domain of type II collagen in extracellular matrix produced by chondrocyte and then induces arthritis. We injected collagenase (0.5, 1.0, 2.0 mg) into the temporomandibular joint of rabbit. In the control group saline was intra-articularly injected. The condylar cartilage, disk and synovia were histologically examined at 1, 2, 4, 6 weeks after the initiation of collagenase injections. Results: Four weeks after injection of 2.0 mg collagenase, we could see histologic change like arthritis. In other groups, we couldn't see arthritis-like change. Conclusion: In our study, we produce arthritis on temporomandibular joint of rabbit by using injection of collagenase in temporomandibular joint of rabbit. And this experimental osteoarthritis is a useful animal model.

발전기 과도현상에 따른 발전기 보호 계전기 동작 분석

권영진(Young-Jin Kwon),강상희(Sang-Hee Kang),김철훈(Chul-Hun Kim) 대한전기학회 2006 대한전기학회 학술대회 논문집 Vol.2006 No.11

Loss of excitation, over excitation and motoring of generator are simulated by using synchronous generator with an exciter and a governor. This paper presents an analysis of transient state of generator and protection relay operation with loss of excitation, over excitation and motoring of generator.

골다공증 유도 백서경골에 티타늄 임플란트 매식 시저출력 초음파 적용이 골 치유에 미치는 영향

황영섭(Young-Seob Hwang),전현준(Hyun-Jun Jeon),신상훈(Sang-Hun Shin),정인교(In-Kyo Chung),김규천(Gyoo-Cheon Kim),김철훈(Chul-Hoon Kim),김욱규(Uk-Kyu Kim) 대한구강악안면외과학회 2011 대한구강악안면외과학회지 Vol.37 No.5

Introduction: Osteoporosis is a major health problem in the elderly that involves changes in the properties of bone as well as impaired bone healing around a titanium implant in both humans and animals. This study examined effect of low intensity pulsed ultrasound (LIPUS) on the bone healing process around a titanium implant in osteoporosis-induced rats. Materials and Methods: Sixteen rats were divided into two groups. A control group with osteoporosis induced by removing both ovaries and an experimental group of rats that were applied with LIPUS after osteoporosis had been induced. A screw type titanium implant (diameter, 2.0 mm: length, 3.5 mm, Cowell-Medi, KOREA) was placed into the tibias of 16 rats. The control and experimental group contained 8 rats each. The rats were sacrificed at 1, 2, 4, and 8 weeks after implantation to examine the histopathology and immunochemistry. Results: The histopathology examination revealed earlier new bone formation in the experimental group than the control group. In particular, at 1 week after implantation, more new bone matrix and collagen were observed around the implant of the experimental group compared to the control group. Immunochemistry analysis showed that the level of OPG expression of the experimental group was higher in the early stages than in the control group. After 8 weeks, the levels of OPG expression were similar in both groups. The expression level of receptor activator of nuclear factor kB ligand (RANKL) was stronger in the experimental group than the control group. After 4 weeks, the level of RANKL expression was similar in both groups. Conclusion: These results suggest that the application of LIPUS to implantation can promote bone healing around titanium in osteoporosis animals.