Safety of Perioperative Maintenance of Antiplatelet Agents in Elderly Patients Undergoing Lung Cancer Surgery

Hee Ju Hong,Ji Hyeon Park,Samina Park,In Kyu Park,Chang Hyun Kang,Young Tae Kim The Korean Society for Thoracic and Cardiovascular 2024 Journal of Chest Surgery (J Chest Surg) Vol.57 No.4

Background: The maintenance of antiplatelet therapy increases the risk of bleeding during lung cancer surgery. Conversely, the perioperative interruption of antiplatelet therapy may result in serious thrombotic complications. This study aimed to investigate the safety of continuing antiplatelet therapy in the context of lung cancer surgery. Methods: We retrospectively reviewed a cohort of 498 elderly patients who underwent surgery for lung cancer. These patients were categorized into 2 groups: group N, which did not receive antiplatelet therapy, and group A, which did. Group A was subsequently subdivided into group Am, where antiplatelet therapy was maintained, and group Ai, where antiplatelet therapy was interrupted. We compared the incidence of bleeding-related and thrombotic complications across the 3 groups. Results: There were 387 patients in group N and 101 patients in group A (Ai: 70, Am: 31). No significant differences were found in intraoperative blood loss, thoracotomy conversion rates, transfusion requirements, volume of chest tube drainage, or reoperation rates for bleeding control between groups N and A or between groups Am and Ai. The duration of hospital stay was longer for group A compared to group N (7 days vs. 6 days, p=0.005), but there was no significant difference between groups Ai and Am. The incidence of cardiovascular or cerebrovascular complications did not differ significantly between groups Ai and Am. However, group Ai included a severe case of in-hospital ST-elevation myocardial infarction. Conclusion: The maintenance of antiplatelet therapy was found to be safe in terms of perioperative bleeding and thrombotic complications in elderly lung cancer surgery patients.

췌담관 합류이상이 있는 환자에서 담도계 손상 기전에 대한 연구

정인호,정용식,김지훈,최수윤,김정운,김욱환,홍정,왕희정,유병무,김진홍,한재호,김영배,김재근,김명욱 한국간담췌외과학회 2003 한국간담췌외과학회지 Vol.7 No.2

서울의 Penicillinase Producing Neisseria gonorrhoeae 발생빈도(1997)

김재홍,문득곤,김정수,김용준,임동진,박상훈,김희성,이민수,송기훈,김갑형,김형석,성소영,이인섭,김석우,황지환,조창근,김경문,부태성 대한화학요법학회 2000 대한화학요법학회지 Vol.18 No.3

Background : In recent years, gonorrhea has been pandemic and remains one of the most common STDs in the world, especially in developing countries. Objective & Methods : For the detection of a more effective therapeutic regimen and assessing the prevalence of PPNG, we have been trying to study the patients who have visited the Venereal Disease Clinic of Choong-Ku Public Health Center in Seoul since 1980 by means of the chromogenic cephalosporin method. Results : In 1997. 99 strains of N. gonorrhoeae were isolated, among which 45(45.5%) were PPNG. Conclusion : The prevalence of PPNG in Seoul, which had been decreased to 39% in 1996 after a peak of 74.3% in 1993, is increased to 45.5% in 1997.

윤리적 소비자가 경험하는 행복한 소비의 특성에 관한 현상학적 연구

송인숙(Song, In Sook),천경희(Chun, Kyung Hee),홍연금(Hong Yeon Geum) 한국소비문화학회 2013 소비문화연구 Vol.16 No.4

This study examined the characteristics of ethical consumer's happiness in consumption empirically. Our viewpoint is that the ethical consumers continue to practice ethical consumption because they experience happiness in those behaviors. We conducted in-depth interview 12 ethical consumers about what they think the happy life or happy consumption is, what they experience in ethical consumption, especially focused on happiness, what kind of difficulties and conflicts do they have in ethical consumption, and analyzed their textual contents applying the qualitative data analysis method of Giorgi's on the phenomenological research. As a result, ethical consumers want to live happily together with all the people surround them, specially with producers, to do meaningful works and to focus on one's inside. Ethical consumers experience happiness in consumption of making relationships with people, doing someone please help, controlling their desires, feeling comforts without doubt, and improving the market environment. On the other hand, the ethical consumers feel burden for the price of ethical products, a conscious effort to find out and ethical reliability issues, the circumstances for inappropriate conditions, and keeping consistency their ethical value orientation in consumption. This study shows ethical consumers practice ethical consumption not only for moral obligation but also for their own happiness. This study also increases the understanding of happy consumption and ethical consumption, so may contribute to the spread of ethical consumption. 본 연구는 윤리적 소비자들이 윤리적 소비를 지속적으로 실천하게 하는 원동력의 본질을 깊이 있게 이해하기 위하여, 윤리적 소비자들이 경험하는 행복한 소비의 특성을 실증적으로 살펴보고자 하였다. 즉 윤리적 소비자들이 윤리적 소비를 지속적으로 실천하게 하는 원동력이 행복을 경험하기 때문이라고 보고 윤리적 소비자가 경험하는 행복한 소비의 특성을 파악하고자 한 것이다. 이를 위해 윤리적 소비자 12명을 대상으로, 윤리적 소비자가 생각하는 행복한 삶은 무엇이며, 윤리적 소비자가 자신의 소비생활에서 경험하는 행복한 소비의 특성은 무엇인지, 윤리적 소비를 실천하면서 겪는 갈등이나 어려움은 무엇인지에 대해 심층 면접하였으며, 이들의 진술을 질적연구방법인 현상학적 연구방법 중 Giorgi의 분석방법을 활용하여 분석하였다. 그 결과, 윤리적 소비자들은 ‘함께 하는 삶’, 즉 나만 좋은 것이 아니라 주위 사람들과 나누는 공동체적인 삶, 본인이 ‘의미 있다고 생각하는 일을 하는 삶’, ‘내적으로 충만하고 소신 있는 삶’을 행복한 삶이라고 인식하고 있었으며, 이들 윤리적 소비자들은 ‘관계를 맺는 소비’, ‘누군가를 돕는 소비’, ‘욕구를 조절하는 소비’, ‘의심하지 않고 안심할 수 있는 소비’, ‘소비환경을 변화시켜 나가는 능동적인 소비’를 하면서 행복감을 경험하고 있었다. 한편, 윤리적 소비자들은 윤리적 소비를 실천하면서 ‘윤리적 제품의 가격에 대한 부담’, ‘윤리적 제품을 찾기 위해 의식적인 노력과 시간의 필요’, ‘윤리적 소비 대상에 대한 신뢰성 문제’, ‘시스템과 여건의 미비’, ‘자신이 가지고 있는 윤리적 소비에 대한 가치관의 일관성을 지키지 못하는 점’ 등에 대한 갈등과 어려움을 경험하고 있었다. 본 연구는 윤리적 소비자들이 도덕적 의무감에서 뿐 아니라 개인의 행복한 소비를 위해서도 윤리적 소비를 실천하고 있다는 것을 실증적으로 밝힌 것으로, 행복한 소비에 대한 이해를 높이고 나아가 윤리적 소비의 확산에 기여할 수 있는 새로운 근거를 제공했다는데 그 의의가 있다.

사람 성상세포종 세포주에서 사이토카인에 의한 Fas 및 FasL mRNA의 발현 조절

김옥준,임정희,최철희,최인홍,이병인,최일생 대한신경과학회 1999 대한신경과학회지 Vol.17 No.1

Uncoupling Protein 3의 골격근 세포내 과발현이 OLETF 백서 및 배양된 골격근 세포에서 포도당대사에 미치는 영향

한정희,박혜선,고정민,김하영,강호경,이인규,박중열,홍성관,이재담,이기업 대한당뇨병학회 2002 Diabetes and Metabolism Journal Vol.25 No.6

연구배경:Uncoupling protein(UCP)는 미토콘드리아의 내막에 위치하는 단백질로 세포내의 과다한 에너지를 열로 발산시키는 기능을 가진다. 최근 동물의 갈색지방조직에만 존재하는 UCP와 유사성을 가진 아형들(UCP2,3)이 사람에게도 존재함이 알려져 큰 관심을 끌도 있는데 이중 UCP3는 그 발현이 골격근세포와 갈색지방조직에만 국한된다. 본 연구에서는 UCP3가 체내 인슐린 감수성을 결정하는데 가장 중요한 조직인 골격근에 국한되어 발현되는 점에 착안하여 UCP3를 골격근세포에 과발현시켰을 때 포도당 대사에 어떠한 영향이 나타나는 지를 조사하였다. 방법:25주령의 8마리의 OLETF 백서를 대상으로 하여 4마리는 골격근에 adenovirus 2mL(1×10¹²pfu/mL)를 주사하여 대조군으로 하였고 4마리는 골격근에 재조합법으로 제작된 adenovirus­UCP3 2mL(1×10¹²pfu/mL)를 주사하였다(UCP3 과발현군). UCP3를 투여한 백서에서 먹이섭취가 증가하는 경향이 있어 그 전날 대조군이 먹은 야의 먹이만큼 투여하였다. 골격근에 adenovirus를 주사한 10일 후에 euglycemic hyperinsulinemic clamp를 시행하였다. Adenovirus­UCP를 C2C12 골격근 세포에 transfection시켜 UCP3를 C2C12 골격근 세포에 transfection시켜 UPS3­C2C12를 만들고 C2C12 골격근 세포와 UPS3­C2C12 골격근 세포에서 포도당 수송 및 당원합성을 측정하였다. 결과:UCP3 과발현 OLETF에서 체중이 감소하는 경향을 보였고 인슐린 감수성이 증가하였다. C2C12세포에서 기저상태 포도당 수송은 1.28±0.17μmol/L/min였고 100nM 인슐린으로 2시간 처리한 후 2.67±0.20 μmol/L/min로 증가하였다. UCP3­C2C12 세포에서는 기저상태 포도당 수송이 3.98±0.13μmol/L/min로 증가되었고 인슐린 처리 후 5.74±0.44μmol/L/min로 증가하였다. 인슐린을 처리한 UCP3­C2C12 세포에 P13K 억제제인 wortmannin을 첨가하였을 때 포도당 수송활성이 3.81±0.20μmol/L/min로 감소하였다. 기저상태 당원합성은 C2C12 세포에서 0.25±0.01μmol/L/min였고 인슐린 처리 후 0.45±0.01μmol/L/min로 증가하였다. UCP3­C2C12 세포에서는 기저상태 당원합성이 0.62±0.01μmol/L/min였고 인슐린 처리 후 1.26±454μmol/L/min로 증가하였다. UCP3­C2C12세포에 wortmannin을 첨가하였을 때 당원합성율이 0.80±0.04μmol/L/min로 감소하였다. 결론:UCP3 과발현이 OLETF 백서에서 인슐린 감수성을 증가시켰고 골격근세포에서 포도당 수송 및 당원합성을 증가시켰다. wortmannin을 첨가하였을 때 포도당 수송 및 당원합성이 감소함으로 보아 이 과정이 인슐린 신호전달체계인 P13K에 일부 의존함을 알 수 있었다. Background : UC P3 is a mitochondrial membrane protein expressed selectively in the skeletal muscle and brown adipose tissue. Since the skeletal muscle is the main organ determining insulin sensitivity in the body, it was hypothesized that UCP3 overexpression in skeletal muscle cells would improve glucose metabolism. Methods : An adenovirus-UCP3 was produced by a recombinant DNA method. OLETF rats were divided into 2 groups. Four rats were injected with the adenovirus-UCP3 (UCP3 group) and others were injected with the adenovirus(control group) in the skeletal muscle. The UCP3 group was provided with the same quantity of food as that consumed by the control group on the previous day. Insulin sensitivity was evaluated by the euglycemic hyperinsulinemic clamp method. In a separate experiment, glucose transport and glycogen synthesis we evaluated in C2C212 cells transfected with ether an adenovirus or the adenovirus-UCP3. Results : The insulin sensitivity improved significantly and the body weight decreased in the UCP3 group. The glucose transport and glycogen synthesis were higher in the UCP3-C2C12 skeletal muscle cells at the basal state. After insulin treatment, glucose transport and glycogen synthesis were also higher in the UCP3-C2C12 cells but the increments were reduced after treatment with wortmannin, a PI3K inhibitor. Conclusion : Insulin sensitivity was higher in the UCP3-overexpressed OLETF rats in the in vivo study. UCP3 transfection also increased glucose transport and glycogen synthesis in the cultured skeletal muscle cells by a PI3K dependent mechanism(J Kor Diabetes Asso 25 :460~468, 2001).

Condylar positioning changes following unilateral sagittal split ramus osteotomy in patients with mandibular prognathism

Kim, Myung-In,Kim, Jun-Hwa,Jung, Seunggon,Park, Hong-Ju,Oh, Hee-Kyun,Ryu, Sun-Youl,Kook, Min-Suk Korean Association of Maxillofacial Plastic and Re 2015 Maxillofacial Plastic Reconstructive Surgery Vol.37 No.-

Background: This study was performed to evaluate three-dimensional positional change of the condyle using three-dimensional computed tomography (3D-CT) following unilateral sagittal split ramus osteotomy (USSRO) in patients with mandibular prognathism. Methods: This study examined two patients exhibiting skeletal class III malocclusion with facial asymmetry who underwent USSRO for a mandibular setback. 3D-CT was performed before surgery, immediately after surgery, and 6 months postoperatively. After creating 3D-CT images by using the In-vivo $5^{TM}$ program, the axial plane, coronal plane, and sagittal plane were configured. Three-dimensional positional changes from each plane to the condyle, axial condylar head axis angle (AHA), axial condylar head position (AHP), frontal condylar head axis angle (FHA), frontal condylar head position (FHP), sagittal condylar head axis angle (SHA), and sagittal condylar head position (SHP) of the two patients were measured before surgery, immediately after surgery, and 6 months postoperatively. Results: In the first patient, medial rotation of the operated condyle in AHA and anterior rotation in SHA were observed. There were no significant changes after surgery in AHP, FHP, and SHP after surgery. In the second patient, medial rotation of the operated condyle in AHA and lateral rotation of the operated condyle in FHA were observed. There were no significant changes in AHP, FHP, and SHP postoperatively. This indicates that in USSRO, postoperative movement of the condylar head is insignificant; however, medial rotation of the condylar head is possible. Although three-dimensional changes were observed, these were not clinically significant. Conclusions: The results of this study suggest that although three-dimensional changes in condylar head position are observed in patients post SSRO, there are no significant changes that would clinically affect the patient.

Prevalence of Latent Tuberculosis Infection among Health Care Workers in South Korea: A Multicenter Study

Jo, Kyung-Wook,Hong, Yoonki,Park, Jae Seuk,Bae, In-Gyu,Eom, Joong Sik,Lee, Sang-Rok,Cho, Oh-Hyun,Choo, Eun Ju,Heo, Jung Yeon,Woo, Jun Hee,Shim, Tae Sun The Korean Academy of Tuberculosis and Respiratory 2013 Tuberculosis and Respiratory Diseases Vol.75 No.1

Background: We investigated the prevalence of latent tuberculosis infection (LTBI) among the health care workers (HCWs) and analyzed its risk factors in South Korea. Methods: A standard questionnaire regarding the baseline demographics and risk factors for LTBI was given to each participant and tuberculin skin test (TST), QuantiFERON-TB GOLD In-Tube (QFT-GIT) assay, and chest radiography were performed. Results: A total of 493 participants, 152 (30.8%) doctors and 341 (69.2%) nurses were enrolled in eight tertiary referral hospitals. The mean age of the subjects was 30.6 years old, and 383 (77.7%) were female. Of the 152 doctors, 63 (41.4%) and 36 (23.7%) were positive by TST and by QTF-GIT, respectively, and among the 341 nurses, 119 (34.9%) and 49 (14.4%) had positive TST and QFT-GIT results, respectively. Overall, the agreement between the two tests was 0.22 by the chance corrected proportional agreement rate (kappa coefficient) in 493 subjects. Experience of working in tuberculosis (TB)-related departments was significantly associated with positive LTBI test results by QFT-GIT assay, not by TST. In multivariate analysis, only age was independently associated with increased risk of a positive TST result, while age and experience of working in TB-related departments (odds ratio, 2.29; 95% confidence interval, 1.01-5.12) were independently associated with increased risk of a positive QFT-GIT result. Conclusion: A high prevalence of LTBI was found among South Korean HCWs. Considering the association between the experience of working in TB-related departments and high risk of LTBI, QFT-GIT may be a better diagnostic test for LTBI than TST in HCWs.

PDGF와 IGF-I 병용 사용시 치주인대세표의 증식과 세포활성에 미치는 영향에 관한 연구

서조영,신홍인,경희문 경북대학교 병원 1997 경북대학교병원의학연구소논문집 Vol.1 No.1

Current acceptable methods for promoting periodontal regeneration are based on removal of diseased soft tissue, root treatment, guided tissue regeneration, introduction of new graft materials and biological mediators. Insulin-like growth factor-I(IGF-I) and Platelet-derived growth factor-BB(PDGF-BB), the members of the polypeptuyde growth factor family have been reported as the biological mediators which regulate a variety cellular matrix biologic activities of wound healing process including the cell proliferation, migration and extracellular matrix synthesis. The purposes of this study is to evaluate the combination effects of IGF-I and PDGF-BB on the cellular activity of the periodontal ligament cells to act as a regeneration promoting agent of periodontal tissue. Human periodontal ligament cells were prepared from the first permolar tooth extracted for the orthodontic treatment and were cultured in DMEM containing 10% FBS at the 37。C, 5% CO2 incubator. Author measured the DNA synthetic activity, and total protein, collagen and noncollagenous protein synthetic activities according to the concentration of 10, 100ng/ml IGF-I and 1, 10 ng/ml PDGF-BB in combination. The results were as follows: significantly increased in the 1 ng/ml PDGF-BB alone compared to the 10 ng/ml PDGF-BB alone(P<0.01)and in the 1 ng/ml PDGF-BB AND 10, 100NG/ML IGF-I in combination compared to the 1ng/ml PDGF-BB alone (P<0.05,P<0.01). The synthetic activity of the noncollagenous protein is increased according to the concentration of IGF_I, but not statistically significant(P>0.05). The percent of collagen is significantly in the 1ng/ml PDGF-BB and 10ng/ml IGF-I in combination compared to the 1ng/ml PDGF-BB alone(P0.05) and in the 10ng/ml IGF-I in combination compared to the 10ng/ml PDGF-BB alone(P<0.05). The synthetic activity of the DNA is in conclusions, the percent study shows that PDGF-BB and IGF-I in combination have a potentiality to enhance the DNA synthesis and the total protein and collagen synthesis of the periodontal ligament cells, especially it is more significant in the low concentration PDGF-BB compared to the high one. Thus, the PDGF-BB and IGF-I in combination may have important roles in promotion of periodontal ligament healing, and consequently, may useful for clinical application in periodontal regenerative procedures.

제1형 탈요오드효소 유전자 갑상선호르몬 반응요소에서 T₃자극에 따른 갑상선호르몬 수용체 역동학 모델

이성진,박철영,정인경,홍은경,최철수,김현규,김두만,유재명,임성희,최문기,유형준,박성우,Larsen, P. Reed 대한내분비학회 2003 Endocrinology and metabolism Vol.18 No.3

연구배경: 제1형 탈요오드효소의 발현에 관여하는 hdiol 유전자는 5 flanking region 내 서로 다른 특성을 가진 두 종류의 갑상선호르몬 반응요소, 즉 TREI과 TRE2를 가지고 있음이 알려져 있다. 사람의 간암세포주인 HepG2 세포에서 T₃를 투여하였을 때 hdiol유전자의 전사작용이 급격하게 증가하는데 hdiol mRNA가 충분히 발현하기 위해서는 두 종류의 갑상선호르몬 반응요소가 모두 필요함이 보고 되어 있으나 T₃ 투여시 갑상선호르몬 반응요소와 결합하는 갑상선호르몬 수용체의 역동학에 대해서는 아직까지 연구된바 없다. 한편 현재까지 보고 된 연구 결과들은 갑상선호르몬 자극이 없더라도 갑상선호르몬 수용체와 갑상선호르몬 반응요소가 서로 지속적으로 상호작용 한다는 전제 조건을 바탕으로 하고 있는데 아직까지 이러한 가정은 간접적으로만 증명되어 있는 상태이다. 이에 저자들은 본 연구에서 사람의 간암세포주인 HepG2세포를 대상으로 염색체 면역침전법과 중합효소연쇄반응을 이용하여 갑상선호르몬 자극 전·후 hdiol 유전자의 갑상선호르몬 반응요소에 결합하는 갑상선호르몬 수용체의 결합양상 변화를 분석함과 동시에 갑상선호르몬 자극 전에도 갑상선호르몬 수용체와 갑상선호르몬 반응요소가 서로 결합된 상태로 존재함을 직접적으로 확인하고자 하였다. 방법: 사람의 간암세포주인 HepG2 세포를 대상으로 100 nM T₃를 투여하기 전과 투여한 후 12시간 뒤 TRα1, TR 1, TR 2 항체와 IREI, TRE2에 상보적인 시발체를 이용하여 염색체 면역침전법과 고식적 중합효소연쇄반응 및 정량적 중합효소연쇄반응을 시행하였다. 100nM T₃를 투여하기 전과 투여한 후 12시간 뒤 hdiol mRNA 발현량의 변화를 정량적으로 측정하기 위하여 역전사 중합효소연쇄반응을 시행하였다. 100 nM T₃를 투여하기 전과 투여한 후 12시간 뒤 TR4'1, TR 1, TR 2 단백질의 발현량을 알아보고자Western blot을 시행하였다. 결과: 100 nM T₃를 투여하기 전과 투여한 후 12시간 뒤 염색체 면역침전법과 TREI 시발체를 이용한 고식적 중합효소연쇄반응을 시행하였을 때 T₃ 투여 전후 TREI 부위에는 TRgl이 결합하였으며 T₃를 투여한 후 TRal 결합이 감소하였다. 정량적 중합효소연쇄반응으로 TR4'1 결합량을 측정하였을 때 T₃ 투여 전3.74에서 T₃ 투여 후 1.97로 감소하여 통계적으로 유의한 차이를 나타내었다(Δ=-47.3%, p<0.05). T₃ 투여 전 ·후 TRβl과 TRβ2의 결합은 관찰되지 않았다. 100 nM T₃를 투여하기 전과 투여한 후 12시간 뒤 염색체 면역침전법과 TRE2 시발체를 이용한 고식적 중합효소연쇄반응을 시god하였을 때 T₃ 투여 전ㆍ후 TRE2 부위에는 TRα1, TR 1, TR 2가 모두 결합하였으며 T₃를 투여한 후 TRα1과 TR 1의 결합은 감소하였으나 TR 2의 결합은 증가하였다. 정량적 중합효소연쇄반응으로 갑상선호르몬 수용체의 결합량을 측정하였을 때 TRαl은 T₃ 투여 전 10.41에서 T₃ 투여 후 3.01, TRβl은 T₃ 투여 전 12.56에서 T₃ 투여 후 2.93으로 유의하게 감소하였으며 TRβ2는 T₃ 투여 전 9.17에서 T₃ 투여 후 9.84로 증가하는 경향을 보였다(TRα1, Δ=-71.1%, p<0.05; TR 1, Δ=-76.7%, p<0.05; TR2, Δ=+7.3%). 정량적 중합효소연쇄반응으로 측정한 갑상선호르몬 수용체의 전체 결합량은 T₃ 투여 전 32.14에서 T₃ 투여 후 15.78로 감소하여 통계적으로 유의한 차이를 나타내었다(Δ=-50.9%, p.0.05). 갑상선호르몬 수용체 항체를 1.5μL와 4.5μL 첨가한 후TREI과 TRE2에 대하여 염색체 면역침전법 및 정량적 중합효소연쇄반응을 각각 시깡하였을 때 첨가한 갑상선호르몬 수용체 항체의 양에 따른 갑상선호르몬 수용체 결합량의 차이는 없었다. 100 nM T₃를 투여하기전과 투여란 후 12시간 뒤 역전사 중합효소연쇄반응 및 hdiol cDNA 시발체를 이용한 정량적 중합효소연쇄반응을 시행하였을 때 T₃를 투여한 후 hdiol mRNA발현량은 2.03배 증가하였다(p<0.001). 100 nM T₃를 투여하기 전과 투여한 후 12시간 뒤 Western blot을 시행하였을 때 갑상선호르몬 수용체 발현량은 유의한 차이가 없었다. 결론: 현재까지 갑상선호르몬 수용체의 역동학에 대한 연구가거의 이루어지지 않았던 실정을고려하여볼 때 본 연구는 제한적이나마 일정한 농도의 갑상선호르몬 자극 전 · 후 갑상선호르몬 수용체 결합양상의 변화, 특히 T₃ 자극 전 hdiol 유전자의 TREI 부위에서 TRal이 억제자 (silencer)로서 작용할 가능성 및 T₃자극 전 · 투 TRE2 부위에서 갑상선호르몬 수용체 교대현상을 처음으로 제시하였다는 점에서 의의가 있으며 향후 다른 종류의 세포주 및 체내에서 갑상선호르몬 자극 전 후 갑상선호르몬 수용체 결합양상의 변화 및 유전자 발현에 미치는 영향을 연구할 필요가 있으리라 생각된다. 한편 염색체 면역침전법을 통해 HepG2 세포에서 T₃ 자극이 없더라도 갑상선호르몬 수용체와 갑상선호르몬 반응요소 사이에 지속적인 상호작용이 존재할 뿐 아니라 갑상선호르몬 반응요소에 대한 갑상선호르몬 수용체의 결합이 교대로 이루어지고 있음을 직접적으로 확인할 수 있었으며 향후 T₃ 자극 전 · 후 갑상선호르몬 수용체를 통한 유전자 전사조절기전에 관여하는 전사인자와 역동학적 기전을 규명함에 있어서 염색체 면역침전법과 정량적 중합효소연쇄반응이 매우 유용하게 이용될 수 있을 것이다. Background: Type 1 iodothyronine deiodinase (Dl), the product of the hdiol gene, is involved in thyroid hormone activation by the deiodination of thyroxine (T4) to form 3,5,3'-triiodothyronine (T3). Recent studies have identified two thyroid hormone response elements (TREs) in the 5 ' flanking region of the hdiol gene. TRE1, proximal to TRE in the hdiol gene, consists of a direct repeat of thyroid hormone receptor (TR) binding octamers with 10 bp separating the two TR binding sites. The upstream TRE, TRE2, is a classical direct repeat of retinoid X receptor (RXR)/TR binding half-sites with a 4-bp separation. There are few studies clarifying the TR dynamics in the TRE of a specific gene with or without the exposure of activated thyroid hormone. We evaluated TR binding patterns in the proximal and distal TREs of the hdiol gene before and after T₃ stimulation. Methods: We employed chromatin immunoprecipitation (ChIP) technique to investigate the TR- TRE interaction before and after T₃ stimulation in human hepatocellular carcinoma HepG2 cell line. Following cross-linking and sonication of the cells, immunoprecipitation was performed overnight at 4℃ with TRαl, TRβ1 and TRβ2 antibodies. We analyzed the binding patterns and amounts of TRαl, TRβl and TRβ2 to TREl and TRE2 before and after 12 hours stimulation with 100 nM T3 by using conventional and quantitative real-time polymerase chain reactions (RQ-PCR). Reverse transcriptional PCR (RT-PCR) and Western blot with TR 1, TR 1 and TR 2 antibodies were performed to measure the levels of hdiol mRNA and TR 1, TR 1 and TR 2 proteins before and after 12 hours exposure to l00nM T3. Results: In TRE1, TRαl binding was significantly decreased after 12 hours stimulation with l00nM T3 (3.74→97, Δ=-47.3%, p<0.05), but TRβ1 and TRβ2 bindings were not detected by conventional PCR and RQ-PCR. Although all TR isoforms were bound to TRE2, the binding patterns were quite different. While TRα1 and TRβ1 bindings to TRE2 after 12 hours stimulation with 100 nM T3 were significantly decreased (10.41→3.01, Δ=-71.1%, p<0.05; 12.56 →2.93, Δ =-76.7%, p<0.05, respectively), TRβ2 binding was increased but not significantly (9.17 →9.84, Δ =+7.3%). Total TR bindings in TRE2 were significantly decreased after 12 hours stimulation with 1OOnM T₃ (32.14 →15.78, Δ=-50.9%, p<0.05). The TR bindings to TREl and TRE2 were not significantly different by the amounts of TR antibodies used during ChIP assays. The levels of hdiol mRNA were significantly increased, 2.03 times, after 12 hours exposure to l00nM T3 (p<O.001). Western blot showed no significant change of the level of each TR isoform protein before and after 12 hours exposure to 100nM T3. Conclusion: Our results demonstrate the dynamics of TRal at proximal TRE (TRE1) and the switching phenomenon of TR isoforms at distal TRE (TRE2) of the hdiol gene after T3 stimulation. Further investigation, however, is needed to clarify the mechanisms of these observations (J Kor SOC Endocrinol 18:283-295, 2003).