Effects of epigallocatechin gallate on CoCl_(2)-induced apoptosis in PC12 cells

Yang, Kyu-Ho,Mo, Hyun-Chul,Choi, Nam-Ki,Kim, Seon-Mi,Kim,Won-Jae 大韓小兒齒科學會 2006 大韓小兒齒科學會誌 Vol.33 No.1

Neuronal apoptotic events, consequently resulting in neuronal cell death, are occurred in hypoxic/ischemic condition. This cell death has been shown to be accompanied with the production of reactive oxygen species (ROS), which can attack cellular components such as nucleic acids, proteins and phospholipid. However, the underlying mechanisms of apoptosis induced in hypoxic/ischemic condition and its treatment methods are unsettled. Cobalt chloride (CoCl_(2)) has been known to mimic hypoxic condition including the production of ROS. Epigallocatechin gallate (EGCG). a green tea polyphenol, has diverse pharmacologial activities in cell growth and death. This study was aimed to investigate the apoptotic mechanism by CoCl_(2) and effects of EGCG on CoCl_(2)-induced apoptosis in PC12 cells. Administration of CoCl_(2) decreased cell survival in dose- and time-dependent manners and induced genomic DNA fragmentation. Treatment with 100 µM EGCG for 30 min before PC12 cells were exposed to 150 µM CoCl_(2), being resulted in the cell viability and DNA fragmentation being rescued. CoCl_(2) caused morphologic changes such as cell swelling and condensed nuclei, whereas EGCG attenuated morphologic changes by CoCl_(2). EGCG suppressed the apoptotic peak and a loss of Δψ_(m) induced by CoCl_(2). CoCl_(2) decreased Bcl-2 expression but Bax expression was not changed in CoCl_(2)-treated cells. EGCG attenuated the Bcl-2 underexpression by CoCl_(2). CoCl_(2) augumented the cytochrome c release from mitochondria into cytoplasm and increased caspase-8, -9 and caspase-3 activity, a marker of the apoptotic executing stage. EGCG ameliorated the incruement in caspase-8, -9 and -3 activity, and cytochrome c release by CoCl_(2). NAC (N-acetyl-cysteine), a scavenger of ROS, attenuated CoCl_(2)-induced apoptosis in consistent with those of EGCG. These results suggest, that CoCl_(2) induces apoptotic cell death through both mitochondria- and death receptor-dependent pathway and EGCG has neuroprotective effects against CoCl_(2)-induced apoptosis in PC12 cells. 신경세포자멸사는 저산소 및 허혈환경에서 일어나며 이러한 세포죽은 reactive oxidant species (ROS) 생성을 동반함이 알려져있다. 그러나, 저산소 및 허혈환경에서 일어나는 세포자멸사의 기전 및 그 치료방법은 아직 정립되어 있지 않다. CoCl_(2)는 ROS를 생성하는 등 저산소환경과 유사한 조건을 초래하는 것으로 알려져 있다. Epigallocatechin gallate (EGCG)는 녹차의 polyphenol 성분으로서 세포성장과 죽음에 다양한 약리학적 효과를 나타냄이 알려져 있다. 본 연구는 PC12 세포에서 CoCl_(2)에 의한 세포자멸사기전을 밝히고 이에 미치는 EGCG의 효과를 조사하는데 목적이 있다. Cell viability는 MTT 측정으로 조사되었고, DNA fragmentation은 DNA laddering으로 조사되었다. Bcl-2와 Bax발현 정도는 RT-PCR로, caspase-3와 -9의 활성은 spectrophotometer, caspase-8의 활성은 flow cytometry에 의해 측정되었다. 미토콘드리아에서 세포질로 분비된 cytochrome c는 western blot으로, 분해된 DNA 양과 미토콘드리아 세포막전위 (Δψ_(m))는 FACScan으로 조사되었다. CoCl_(2)투여로 PC12 세포수는 용량 및 시간 의존형태로 감소하였고, genomic DNA fragmentation이 발생하였다. CoCl_(2)투여로 야기된 cell viability의 감소와 DNA fragmentation은 EGCG 전처치에 의해 억제되었다. CoCl_(2)은 세포용적팽창과 condensed nuclei 같은 형태적 변화를 일으켰으며, apoptotic peak, Δψ_(m)감소 및 cytochrome c 유리를 야기하였다. EGCG는 CoCl_(2)에 의한 세포형태변화, apoptotic peak, Δψ_(m)소실 및 cytochrome c 유리를 억제시켰다. CoCl_(2)는 Bcl-2 발현을 감소시켰지만, Bax 발현에는 영향을 미치지 않았다. EGCG는 CoCl_(2)에 의해 야기된 Bcl-2 발현 감소를 억제시켰다. CoCl_(2)는 caspase-3, -8, 그리고 -9의 활성을 증가시켰으며, EGCG는 CoCl_(2)에 의한 세포자멸사를 억제시켰다. 본 실험결과는 PC12 세포에서 CoCl_(2)가 미토콘드리아 의존 및 death receptor의존 기전으로 세포자멸사를 일으키며, EGCG는 세포자멸사기전을 억세지킴으로 신경보호기능을 가짐을 시사하였다.

8년간(1992~1999) 산업안전보건연구원에 의뢰된 직업병 심의 사례 분석

강성규,김규상,김양호,최정근,안연순,진영우,최병순,양정선,김은아,채창호,최용휴,김대성,박정선,정호근 대한산업의학회 2000 대한직업환경의학회지 Vol.12 No.2

Objectives : Pneumoconisis and noise-induced hearing loss (NIHL) have been reported as main occupational diseases by the Special Health Examination. The Industrial Accident Compensation Insurance has reported various work-related diseases, however, these two diseases occupied almost a half of compensated cases. Therefore, it was not well known about the status of occupational diseases other than pneumoconiosis, NIHL, and cardio-cerebrovascular accident (CVA). This study was conducted to analyze claimed cases as an occupational disease, that was requested to the Korea Industrial Safety and Health Agency (KOSHA). Methods : The local office of the Korea Labor Welfare Corporation (KLWC) has asked the KOSHA for confirmation of claimed cases as an occupational disease. We analyzed 379 cases requested from KLWC, the Ministry of Labor, employers, unions and occupational health agencies from 1992 to 1999. Results : Male was 80.7 % of the requested cases. Their mean age was 42 years old and 75.5 % of them were more than 35 years old. The requested cases were increased rapidly from 25 cases in 1992 to 108 cases in 1999 and the accept rate was 50.7 %. The majority of requested cases were respiratory diseases(22.4%), cancers(18.5%), Neuropsychiatric problems(14.5%), and musculoskeletal problems(13.5%). The accept rate was high in reproductive, respiratory, musculoskeletal and digestive disorders and low in neuropsychiatric, renal and otologic problems and occupational cancers. 73.6% of them were caused by chemical agents, especially 28.5 % were by organic solvents. 67% of them were clinically confirmed at university hospitals. A half of the cases were from KyongIn area, even the request came from the whole country. Conclusions : A claim was common in workers whose age was over 35 years old and exposure history was over 10 years. The respiratory diseases and neuropsychiatric disorders were still main problems in occupational health and occupational cancers was increasing even though its accept rate was not high yet.

유치열의 이중치 및 결손치의 발생빈도와 영구치열과의 상호관계

양규호,임혜정,최남기,김선미 대한소아치과학회 2007 大韓小兒齒科學會誌 Vol.34 No.3

Congenital Insensitivity to Pain with Anhidrosis 환아의 치험례

양규호,최남기,김태근 大韓小兒齒科學會 1999 大韓小兒齒科學會誌 Vol.26 No.1

본 병원에 동통을 느끼지 못하는 것으로 인한 혀나 손가락 깨물기 등이 자가 손상,무한증,반복적 발열등의 임상증상을 보이며 유전성이 없이 CIPA로 내원한 환아에서 보호자에게 세심한 보호와 우발사고 방지에 대한 교육이 무엇보다도 중요하며, 치면세마,불소도포,소와열구전색등의 예방적인 처치와 주기적으로 내원시켜 치과적인 문제를 조기에 해결하는 것이 필요하다고 사료된다. Congenital Insensivity to Pain with Anhidrosis(CIPA) is rare autosomal recessive disorder which is known to be hereditary sensory and autonomic neuropathies(HSAN) typeⅣ. It is predilection for male and observed in early infant. Its clinical features include congenital analgesia, which leads to self-mutilation; inability to sweat, which leads to defective thermoregulation; and mild to moderate mental retardation. Its dental features include self-mutilation by nail peeling, which leads to gingival ulcer, tongue ulcer due to tongue biting, and enamel hypoplasia. Partial anodontia is often observed as well. Seventeen-months-old boy with CIPA was reported. This is the case in which the dental characteristics are described and the dental treatment of patient is discussed.

하악골 성장 지표로서 경추골 성숙도의 유용성

최봉선,최남기,김선미,양규호,정성수 大韓小兒齒科學會 2007 大韓小兒齒科學會誌 Vol.34 No.4

This study was to investigate if cervical vertebrae maturation stages are as useful as hand-wrist maturation stages in evaluating the mandibular growth. The subject consisted of 292 girls aged from 8 to 16 years with normal occlusion. They were classified according to diagnosis by using studycast. lateral cephalogram, and handwrist X-ray film. The results were as follow: 1. Cervical vertebrae and hand-wrist maturation stages increased with age. 2. All mandibular measurements (Ar-Go, Go-Me, N-Go, S-Gn, N-Me) increased linearly with cervical vertebrae maturation stages. 3. Ar-Go, Go-Me, N-Go, S-Gn increased linearly with hand-wrist maturation stages. 4. Ar-Go, Go-Me, N-Go, S-Gn increased relatively rapidly between cervical vertebrae maturation stages 3 and 4. Go-Me and S-Gn increased relatively rapidly between hand-wrist maturation stages 6 and 7. 5. Ar-Go, Go-Me, N-Go, S-Gn, N-Me had high correlations with cervical vertebrae maturation stages as well as hand-wrist maturation stages. These results suggest that cervical vertebrae maturation stages are reliable on evaluating the mandibular growth. 하악골 성장을 평가하는 데 경추골 성숙도가 수완부골 성숙도만큼 유용한가 규명하고자 본 연구를 시행하였다. 정상교합을 가진 만 8세∼만 16세 여성 292명을 연구대상으로 하여 진단석고모형,측모두부규격방사선사진,그리고 수완부방사선사진을 이용하여 경추 및 수완부의 골성숙도를 비교하여 다음과 같은 결과를 얻었다. 1. 연령 증가에 따라 경추 및 수완부의 골성숙도가 일정하게 증가하였다. 2. 경추골 성숙도가 증가할수록 Ar-Go,Go-Me,N-Go,S-Gn,N-Me이 일정하게 증가하였다. 3. 수완부골 성숙도가 증가할수록 Ar-Go,Go-Me,N-Go,S-Gn이 일정하게 증가 하였다. 4. 경추골 성숙도 3단계와 4단계 사이에서 Ar-Go,Go-Me,N-Go,S-Gn이 크게 증가하였고,수완부골 성숙도 6단계와 7단계 사이에서 Go-Me,S-Gn이 크게 증가 하였다. 5. Ar-Go,Go-Me,N→Go,S一Gn,N-Me은 경추 및 수완부 골성숙도와 각각 유의 한 상관성을 보였다. 이상의 결과는 하악골 성장을 평가하는 데에 경추골 성숙도가 수완부골 성숙도처럼 유용하게 사용될 수 있음을 시사한다.

정상교하 아동의 두개안면부 성장에 관한 종적 연구

양규호,박창헌,손정수,김낙현,최남기,김선미,김기백,신혜성 大韓小兒齒科學會 2009 大韓小兒齒科學會誌 Vol.36 No.3

혼합치열기 정상교합 아동 24명(남:14명 여:10명 초진 시 평균 나이 9±1.3세, 평균 관찰 기간: 13±1.3개월)에 대한 성장량을 측정하여 기능적 교정장치의 순수 치료효과를 평가하는데 도움이 되기 위해 3회(5~8개월 간격) 촬영한 측모 두부 방사선 규격 사진에 대한 분석 결과 다음과 같은 결론을 얻었다. 1. 남아는 상악골은 전하방, 하악골은 전방성장하였고, 여아는 상하악골이 전하방 성장하였다(p<0.05). 2. 상하악골의 남녀간 차이에서 수평적 성장상태는 여아가 컸고(A point 여아: 2.39mm, 남아: 1.26mm, p<0.05), 수직적 성장상태는 유의한 차이가 없었다. 3. 상악 전치의 치축은 두개저에 대해서 순측 경사하였고(p<0.01) 하악 전치의 치축은 큰 변화가 없었다. The purpose of this study was to provide the reference data evaluating the treatment effect of orthopedic appliances. The skeletal and dental growth increments were measured in 24 normal mixed dentition children(boys: 14, girls: 10) by three serial lateral cephalograms: initial mean age: 9±1.3 years, mean observation period: 13±1.3 months, Cephalometric changes were analysed. The results were as follows: 1. In boys, the maxilla showed forward and downward growth pattern and the mandible showed forward growth pattern(p<0.05). In girls, the maxilla and mandible showed forward and downward growth pattern(p<0.05). 2. Horizontal growth of both maxilla and mandible in girls was superior to those in boys(A point: girls: 2.39mm, boys: 1.26mm, with p<0.05), whereas vertical growth of both maxilla and mandible in boys was similar to those in girls. 3. The change in tooth axis showed labioversion of upper incisor(p<0.01) and comparatively stable lower incisor position.

이유백서에서 교근절제후 하악과두의 면역조직화학적 연구

최남기,양규호 전남대학교 치과대학 1995 전남치대논문집 Vol.7 No.1

The purpose of this study was to determine whether there was any correlation between temporomandibular joint dysfunction and structure of the mandibular condyle. Weanling rats had their masseter muscles resected and immunohistochemical findings were observed a light microscope. The results obtained were as follows : 1. The condylar cartilage region was divided into articular, proliferating, cartilage cell and hypertrophic cell layers according to cell morphology. 2. In light microscopic views, the proliferating and cartilage cell layers of the experimental group decreased gradually and at the 8the week significantly. 3. In immunohistochemical staining for type Ⅰ and Ⅱ collagen, a reaction was detected in the lower part of proliferating cell and cartilage cell layers. In the acrtilage cell layers, a stronger cellular reaction was present. Immunohistochemical staining for type Ⅱ collagen reacted more strongly than that of type Ⅰ collagen. 4. In immunohistochemical staining for proteoglycan, the staining of the experimental group resembled the control group and gradually showed a weak reaction. The proliferating and cartilage cell layers reacted more strongly than the hypertrophic cell layer. 5. In immunohistochemical staining for proliferating cell nuclear antigen(PCNA), the strong reaction was detected in the nucleus of the proliferating cell layer both in control and experimental groups. But the thickness of the proliferating layer decreased in experimental group, consequently the reaction of the experimental group was reduced more than that of the control group.

이유백서에서 교근절제후 하악과두의 면역조직화학적 연구

최남기,양규호,최홍란 大韓小兒齒科學會 1996 大韓小兒齒科學會誌 Vol.23 No.2

The purpose of this study was to determine whether there was any correlation between temporomandibular joint dysfunction and structure of the mandibular condyle. Weanling rats had their masseter muscles resected and immunohstochemical findings were observed with a light microscope. The results obtained were as follows: 1.The condylar cartilage region was divided into articular,proliferating,cartilage cell and hypertrophic cell layers according to cell morphology. 2.In light microscopic views,the proliferating and cartilage cell layers of the experimental group decreased gradually and at the 8th week significantly. 3.In immunohistochemical staining for type Ⅰand Ⅱ collagen,a reaction was detected in the lower part of proliferating cell and cartilage cell layers.In the cartilage cell layers,a stronger cellular reaction was present.Immunohistochemical staining for type Ⅱ collagen reacted more strongly than that Ⅰ collagen. 4.In immunohistochemical staining for proteoglycan,the staining of the experimental group resembled the control group and gradually showed a weak reaction.The proliferating and cartilage cell layers reacted more strongly then hypertrophic cell layer. 5.In immunohistochemical staining for proliferating cell nuclear antigen(PCNA),the strong reaction was detected in the nucleus of the proliferating cell layer both in control and experimental groups.But the thickness of the proliferating layer decreased in experimental group,consequently the reaction of the experimental group was reduced more than that of the control group.

복합레진 표면에 대한 APF gel의 영향

최남기,육근영,양규호,김선미 大韓小兒齒科學會 2006 大韓小兒齒科學會誌 Vol.33 No.1

소아의 치아우식증을 예방하기 위한 불소의 국소도포는 소아치과 영역에서 널리 시행되고 있다. 하지만 이러한 잇점에도 불구하고 최근 수복물 표면을 거칠게 한다는 부작용에 대해 논란이 되고 있다. 이에 본 연구에서는 불소도포가 심미 수복물의 표면변화에 미치는 영향을 평가하기 위해 수종의 복합레진에 국소도포용 불소젤을 도포시킨 후 변화를 관찰하였다. 시판용 레진인 Z 250(3M ESPE, USA), Ultraseal XT^(®)(Ultradent, USA), Filtek flow^(®)(3M, USA) , Revolution^(®)(Kerr, USA), Denfil^(®)(Vericom,Korea)를 이용하여 시편을 제작하고, 불소젤은 Topex^(®)(Sultan Dental Products,Canada)을 각각 1분과 4분동안 도포시켰다. 각 제품마다 불소젤을 도포하지 않은 5개의 시편을 대조군으로 사용하였다. 그 후 이 시편들의 표면 거칠기(Ra value,㎛)와 무게 차이를 측정하고 주사전자현미경을 이용하여 다음과 같은 결과를 얻었다. 1. 불소젤을 도포시키지 않은 대조군에서 가장 평활한 표면을 보였으며 1분군, 4분군 순으로 표면 거칠기가 증가하였다. 그리고 Revolution을 제외한 모든 제품에서 유의한 차이를 보였다(p<0.05). 2. 국소도포용 불소젤을 도포한 각 레진 시편의 무게 차이를 비교한 결과 대조군, 1분군, 4분군 간에 유의한 차이는 없었다(p>0.05). 3. 주사전자현미경 관찰시 불소젤에 도포시킨 실험군은 대조군에 비해 거친 표면을 나타냈다. 이상의 결과로 국소적 불소도포는 복합레진의 표면 거칠기에 영향을 미치며 이를 고려하여 사용한다면 4분보다는 1분간의 불소도포법을 이용하는 것을 추천할 수 있을 것으로 사료된다. Topical fluoride application for children is a widely performed procedure in the field of pediatric dentistry to prevent dental caries. However, it is recently recognized as having some unwanted effects on several esthetic restorative materials as it roughens the surface of the restorative materials. The aim of this study was to evaluate the surface changes in composite resins to topical fluoride. Composite resins(Z 250^(®),Ultraseal XT^(®),Filtek flow^(®),Revolution^(®),Denfil^(®))in topical fluoride agents were immersed and their surface roughness, weight loss and SEM were evaluated. The results were as follows: 1. The 4 minutes-immersion groups showed more roughened surface than 1 minute-immersion groups and the control groups showed the smoothest surface among all the materials, and there was statistically significant difference except the revolution between the groups. 2. There was no significant difference between the 1 minute-immersion groups and 4 minutes-immersion groups in weight loss. 3. The experimental group treated with topical fluoride gel showed the generally mere roughened surface than control group in the SEM findings.

Hypophosphatemia rickets 환아의 증례보고 : A CASE REPORT

양규호,최남기,김선미,정희경 大韓小兒齒科學會 2005 大韓小兒齒科學會誌 Vol.32 No.1

Hypophosphatemia rickets는 비타민 D의 치료량에 내성을 갖기 때문에 Vitamin D-resistant rickets(VDRR)라고도 명명되며, 이는 요세관으로부터 무기질 인산의 재흡수가 감소됨으로써 혈청 칼슘농도는 정상이나 인산농도가 낮고 alkaline phosphatase가 약간 증가되기 때문에 쉽게 진단되는 구루병의 한 형태이다. 이러한 Hypophosphatemia rickets의 임상적인 소견으로 양 다리가 휘는 것, 작은 키, 척추측만, 손목과 발목부위의 팽대가 나타나며 구강내 소견으로는 자발적인 치성농양의 높은 발생률, 맹출 지연, 근단공의 폐쇄지연, 얇고 저형성된 법랑질, 명확히 인지하기 힘든 치조백선, 확대된 치수강, 법랑상아경계까지 연장된 치수각 등이 있다. 본 증례는 유치의 상실과 그에 따른 치료를 위해 본원 소아과에서 의뢰된 비타민 D 저항성 구루병 환아의 임상소견과 그 치과적 치료에 대해 보고하는 바이다. Hypophosphatemia rickets, also known as Vitamin D-resistant rickets(VDRR) and refractory rickets, is a form of rickets which is resistant to the usual doses of vitamin D. VDRR is characterized by decreased renal tubular reabsorption of inorganic phosphate and is easily diagnosed by a normal blood calcium, hypophosphatemia, and slightly elevated alkaline phosphatase. Clinical features of Hypophosphatemia rickets included lateral bowing deformities of the legs, short stature, scoliosis, and enlargement of wrist and ankles. Dental finding in patient with VDRR were spontaneous dental abscesses in caries free teeth and other dental findings included delayed eruption, delayed apical closure, thin and hypoplastic enamel, absent or poorly defined lamina dura, enlarged pulp chambers, and numerous accessory canals and pulp horns that extend up and into the dentinoenamel junction. we reported the clinical feature and treatment of VDRR child who was referred from the department of pediatrics for early loss of primary teeth and its treatment.