폐쇄성 수면무호흡 환자의 상기도 형태의 특징과 압력강하에 관한 3차원 전산유체역학해석

모성서,안형택,이정선,정유삼,문윤식,배응권,성상진 대한치과교정학회 2010 대한치과교정학회지 Vol.40 No.2

폐쇄성 수면무호흡(obstructive sleep apnea, OSA)은 수면 중에 반복적으로 상기도의 완전폐쇄나 부분폐쇄가 일어나는 질환으로서 흡기된 공기는 반드시 상기도라는 연조직 관(tube) 구조를 통과해야 하므로 상기도의 폐쇄경향은 관의 형태 및 관을 통과하는 공기의 유체역학적 특성에 따라서도 큰 영향을 받을 수 있다. 본 연구에서는 OSA 환자 3인의 치료 전 상기도 CT 이미지를 이용하여 개별화된 3차원 유한요소모델 A, B, C를 제작하고, 비공 당 170, 200, 230 ml/s의 흡기유량에 대하여 3차원 전산유체역학 해석을 시행하였다. 상기도의 유속, 음압 그리고 압력강하를 측정한 결과 관찰된 3개의 모델에서 모두 단면적이 가장 작은 부위에서 유속이 증가하였고, 음압이 크게 나타났다. 기도의 형태는 구개인두와 구인두 부위에서 좁아지는 형태를 가지며, 최소 단면적 영역과 하인두 단면적의 차이가 클수록 유속과 음압의 변화가 크게 나타났다. 비강 부위의 최고 압력과 최소 단면적 영역의 최저 압력의 차이를 의미하는 압력강하는 상기도 저항을 종합적으로 판단할 수 있는 유용한 지표이며, 유량에 따라 증가하였다. Objective: Obstructive sleep apnea (OSA) is a common disorder which is characterized by a recurrence of entire or partial collapse of the pharyngeal airway during sleep. A given tidal volume must traverse the soft tissue tube structure of the upper airway, so the tendency for airway obstruction is influenced by the geometries of the duct and characteristics of the airflow in respect to fluid dynamics. Methods: Individualized 3D FEA models were reconstructed from pretreatment computerized tomogram images of three patients with obstructive sleep apnea. 3D computational fluid dynamics analysis was used to observe the effect of airway geometry on the flow velocity, negative pressure and pressure drop in the upper airway at an inspiration flow rate of 170, 200, and 230 ml/s per nostril. Results: In all 3 models, large airflow velocity and negative pressure were observed around the section of minimum area (SMA), the region which narrows around the velopharynx and oropharynx. The bigger the Out-A (outlet area)/ SMA-A (SMA area) ratio, the greater was the change in airflow velocity and negative pressure. Conclusions: Pressure drop meaning the difference between highest pressure at nostril and lowest pressure at SMA, is a good indicator for upper airway resistance which increased more as the airflow volume was increased.

발포폴리스티렌비드를 사용한 경량콘크리트의 역학적 특성에 관한 실험적 연구

주재금,이종찬,오세출,유택동,정광량,서치호 대한건축학회 2003 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.23 No.1(구조계)

The purpose of this study is to obtain basic data on the properties of the lightweight concrete within expanded polystyrene beads for various applications in the field. Inquiring into the change of the properties as altering cement matrix mixture and the capacity mixture ratio of expanded polystyrene beads, the mixture plane of this study is set up as W/C is fixed 50%, expanded polystyrene beads is increased 10% from 0% to 80% per 1m³ and the ratio of cement:sand in the cement matrix is 1:0, 1:0.5, 1:1. The results of this study are as follow. The slump as changing the mixture ratio of expanded polystyrene beads decrease smoothly until mixture ratio 50% but decrease rapidly being in excess of 50%. The density decrease regularly as the mixture ratio of expanded polystyrene beads increase but the ratio of strength decrease. The difference of cement matrix. The strength of cement matrix having more sand mixture ratio relatively decrease rapidly as increasing the mixture ratio of expanded polystyrene beads. It is judged decreased strength phenomenon as the quantity of coherent material created in the mixture decrease rapidly.

Production of Gericudranins by Hairy Root Culture of Cudrania tricuspidata

Seo, Weon Taek,Lee, In Kyoung,Yoo, Ick Dong,Park, Young Hoon 한국미생물 · 생명공학회 1995 Journal of microbiology and biotechnology Vol.5 No.4

Production of new flavanol derivatives with cytotoxic activity, gericudranin A and B, was studied by using hairy root cultures of Cudrania tricuspidata. Schenk and Hildebrandt (SH) medium was chosen for root growth and gericudranin production. After 35 days culture in a half-strength liquid SH medium containing 30 g^glucose/ℓ hairy root growth reached 138 g^Fw/ℓ and gericudranin A and B were produced at concentrations of 27 ㎎/ℓ and 21 ㎎/ℓ, respectively. It was also observed that the contents of gericudranin A and B in hairy root were eight and six times higher than those of cudraniae radix, respectively.

Limb Lengthening in the Osteoporotic Bone

Hui Taek Kim(김휘택),Seong Ho Whang(황성호),Jeong Han Kang(강정한),Jong Seo Lee(이종서),Sang Jin Cheon(천상진),Chong Il Yoo(유총일),Hee Kyung Chang(장희경) 대한정형외과학회 2005 대한정형외과학회지 Vol.40 No.8

목적: 스테로이드로 골 다공증을 유도한 가토에서 신연 골형성을 연구하였다. 대상 및 방법: 성숙한 가토에서 스테로이드 투여 용량에 따라 1군(스테로이드를 투여하지 않은 군), 2군(0.4 ㎎/㎏/day 2주간 투여한 군), 3군(0.4㎎/㎏/day 4주간 투여한 군), 4군(0.8 ㎎/㎏/day 2주간 투여한 군), 5군(0.8 ㎎/㎏ 4주간 투여 한 군)으로 나누었다. 스테로이드 투여 후 경골 간부에 외고정 기구를 고정한 후 절골술을 시행하였으며 4주간 골신연술을 시행하였다. 1주마다 단순 방사선 사진 촬영과 골밀도 및 퍼센티지 골밀도를 측정하고, 최종 신생골 형성 정도에 따라 3개의 군으로 나누어 조직학적 분석을 하였다. 결과: 양호한 가골을 형성한 가토는 모두 1군이었다. 그들의 요추 골밀도는 평균 5.1% 감소되었으며, 신연 1주 후 신연부 퍼센티지 골밀도는 50 이상이었다. 결론: 성숙한 가토에서 요추 골밀도가 10% 이상 감소되었거나, 신연 1주 후 퍼센티지 골밀도가 50 미만인 경우 사지 연장술 중 문제점의 발생이 예상된다. 인체에 있어서도 유사한 수치가 적용될 수 있으리라 생각된다. Purpose: This study investigated the results of distraction osteogenesis in steroid-induced osteoporotic rabbits. Materials and Methods: Mature rabbits were assigned to the following five steroid dosage groups: Ⅰ (none); Ⅱ (0.4 ㎎/㎏/day for 2 weeks); Ⅲ (0.4 ㎎/㎏/day for 4 weeks); Ⅳ (0.8 ㎎/㎏/day for 2 weeks); Ⅴ (0.8 ㎎/㎏/day for 4 weeks). After the steroid injection, the tibias were osteotomized and distracted for 4 weeks. The rabbits were classified radiographically into three groups according to the quality of new bone formed, and the Bone mineral density (BMD) and percentage BMD for these groups were then compared. The microscopic results supported the radiographic groupings. Results: The rabbits that formed good calluses were all from group Ⅰ, and their average lumbar BMD remained high (mean decrement, 5.1%). These rabbits had a percentage BMD ≥50 after 1 week of the distraction. Conclusion: Problems can be expected during limb lengthening in mature rabbits that shows a lumbar BMD decrease ≥10%, or a percentage BMD <50 after 1 week of the distraction. Similar guidelines may be indicated for humans.

그레이브스병에서 치료에 따른 폐동맥압의 변화

남택만,조한수,이진서,송영림,김두만,두영철,박철영,정인경,홍은경,이성진,오기원,김현규,유재명,최문기,유형준,박성우 대한내분비학회 2003 Endocrinology and metabolism Vol.18 No.5

연구배경: 갑상선기능항진증에 의한 갑상선중독증 환자들은 호흡곤란을 호소하며, 그 원인으로 호흡근의 근력 약화, 좌심실부전으로 인한 폐모세혈관의 울혈, 기도저항의 증가, 갑상선종으로 인한 기관의 압박, 호흡기능 이상 등이 거론되고 있다. 폐동맥고혈압이 동반된 그레이브스병 환자가 여러 증례가 보고되었으며, 폐동맥고혈압 환자에게서 갑상선 자가항체와 갑상선기능저하증의 빈도가 높음이 알려지면서 갑상선중독증이 동반된 그레이브스병 환자에게서 관찰되는 호흡곤란의 한 원인으로 폐동맥압 증가가 작용할 가능성이 제시되고 있다. 이에 저자 등은 그레이브스병 환자를 대상으로 폐동맥압을 측정하고 치료 전후의 폐동맥압의 변화를 전향적으로 연구하였다. 방법: 갑상선중독증이 동반된 그레이브스병 환자와 정상 갑상선기능을 나타낸 대조군을 대상으로 갑상선기능검사 및 갑상선 자가항체를 측정하고, 심초음파를 이용하여 치료 전후로 폐동맥압을 측정하여 폐동맥압과 갑상선기능 및 갑상선 자가항체와의 관계, 폐동맥압의 변화 등을 관찰하였다. 결과: 1. 연구대상은 대조군 10명 (남녀비 1:9, 관해 상태의 그레이브스병 3명, 갑상선종 3명, 정상인 4명), 그레이브스병 환자 26명 (남녀비 7:19)이었다. 2. 대조군과 치료 전 그레이브스병 환자의 폐동맥압은 각각 23.5±2.32 mmHg, 29.6±10.3 mmHg이었고, 치료 전의 폐동맥압과 혈청 갑상선자극호르몬 결합억제 면역글로불린 (TBII) 농도는 유의한 양의 상관관계를 보였다. 3. 26명의 그레이브스병 환자 중에서 10명 (38.5%)이 폐동맥고혈압 (기준: 폐동맥압 > 30 mmHg)으로 진단되었다. 4. 치료 전후로 폐동맥압을 측정한 13명은 폐동맥압이 치료 전 29.6±10.3 mmHg에서 치료 후 폐동맥압 22.2±6.48 mmHg로 의미있게 감소하였다. 결론: 갑상선중독증을 보이는 그레이브스병 환자의 약 40% 정도에서 폐동맥고혈압이 발견되어 폐동맥고 혈압은 그레이브스병에 흔하게 동반하는 질환으로 생각된다. 향후 그레이브스병 환자에서 관찰되는 폐동맥압의 증가와 관련한 병인, 발생기전 및 임상적 의의 등에 대한 연구가 필요할 것으로 생각된다. Background: Exertional symptoms, dyspnea and impaired effort tolerance are common in patients with Graves' disease. Proposed explanations include: high-output left heart failure, ineffective oxygen utilization and respiratory muscle weakness. In addition, pulmonary hypertension has also been reported in patients with Graves' disease. A high prevalence of hypothyroidism and positive thyroid autoantibody were also observed in patients with pulmonary arterial hypertension. Therefore, the pulmonary artery pressure in patients with Graves' disease was evaluated. Methods: Two-dimensional and Doppler echocardiographic examinations (Hewlett Packard Sonos 2500) were performed to determine the pulmonary artery (PA) pressure in 26 Graves' disease patients, both before and after treatment (23 patients with propylthiouracil and 3 with RAI), and in 10 euthyroid controls. The changes in the PA pressure after treatment were evaluated in 13 patients with Graves' disease, who became euthyroid after treatment. Results: The pulmonary artery pressure was increased in the untreated Graves' disease patients compared to the normal controls (23.5±2.32 vs. 29.6±10.3 mmHg). 38.5% of the Graves' disease patients (10/26) showed pulmonary arterial hypertension (PA>30 mmHg) and the serum TBII level was higher in the Graves' disease patients with pulmonary arterial hypertension than in those with normal PA pressure (P<0.05). In the Graves' patients who became euthyroid after treatment, the PA pressure was significantly decreased. Conclusion: 38.5% of the untreated Graves' disease patients showed pulmonary arterial hypertension, and the pulmonary artery pressure was significantly decreased in those who became euthyroid after treatment. The pathogenesis and clinical importance of pulmonary arterial hypertension in Graves' disease requires further studies (J Kor Soc Endocrinol 18:465∼472, 2003).

TIMP-1 inhibits apoptosis in breast carcinoma cells via a pathway involving pertussis toxin-sensitive G protein and c-Src

Lee, Seo-Jin,Yoo, Ho Jung,Bae, Yun Soo,Kim, Hwa-Jung,Lee, Seung-Taek 梨花女子大學校 藥學硏究所 2003 藥學硏究論文集 Vol.- No.12

In addition to inhibiting matrix metalloproteinases. tissue inhibitor of metailoprotemase-1 (TIMP-1) is involved in the regulation of cell growth and survival. To determine its mechanism of action, we investigated effects of TIMP-1 on cell proliferation and survival and signaling pathways induced by TIMP-1 in the human breast carcinoma T-47D cell line. Treatment of T-47D cells with TIMP-1 strongly inhibited apoptosis induced by serum deprivation, but did not affect cell protiferation. TIMP-1 induced phosphorylation of Akt and extracellular signal-regulated protein kinases (ERKs). but pertussis toxin and specific inhibitors of Src family tyrosine kinases, protein tyrosine kinases, and phosphatidylinositol-3 kinase (PI3 kinase) blocked the ability of TIMP-1 to activate Akt and ERKs as well as the anti-apoptotic effect of TIMP-l .We found that TIMP-1 enhanced the kinase activities of c-Src and P13 kinase and that this enhancement was inhibited by pertussis toxin. Inhibition of ERK activation, however, resulted in a slight decrease of the TIMP-1-induced anti-apoptotic effect. These findings demonstrate that the ability of TIMP-1 to inhibit apoptosis in T-47D cells is mediated by the sequential activation of pertussis toxin-sensitive G protein. c-Src. PI3 kinase. and Akt.

임팩트시 테니스 라켓 재질의 차이에 따른 근전도 분석

윤양진,유국종,서국웅,정미라,강영택,이훈식,서국은 釜山大學校 附設 體育科學硏究所 1999 體育科學硏究所 論文集 Vol.15 No.-

The purpose of this paper is to select 7 male athletes and female athletes of high school, and to compare their active potential differences of upper arm muscles according to characteristic of a racket. the results obtained are as follows: 1. According to the accumulative distribution rate of racket material, graphite and wood material show better efficiency in case of brachio radialis muscle of male athletes, but the racket material shows no constant efficiency in brachii radialis muscle of female athletes. In case of flexor carpi radialis muscle, wood material provides better efficiency only for male athletes. In case of triceps brachii muscle, wood material gives better efficiency to males athletes and steel material gives better efficiency to females athletes. Especially in case of biceps brachii muscle, neither male nor female athletes are influenced by racket materials at impact. 2. In the muscle load rate according to racket material, wood has the highest muscle active potential and graphite has the lowest active potential. Therefore, graphite is thoght to be better in the efficiency of muscle load rate.

The Controlling Greenhouse Using ZigBee Wireless Network for Crop Production and Quality

Hun Kyo Seo,Jong Pill Han,Yoo Taek Seo,Yeo Jin Jung,Kwon Kyoo Kang,Yu Jin Jung 한국원예학회 2015 한국원예학회 학술발표요지 Vol.2015 No.5

응력집중과 변위를 고려한 연료전지 시스템 프레임의 구조최적설계

박광서(Kwang Seo Park),전유택(Yoo Taek Joen) 대한기계학회 2013 대한기계학회 춘추학술대회 Vol.2013 No.5

가토 대퇴골의 골 연장술에 따른 좌골신경의 생리학적 및 조직학적 변화

김휘택(Hui Taek Kim),서용호(Yong Ho Suh),백상대(Sang Dae Baek),이종서(Jong Seo Lee),박순미(Soon Mi Park),장희경(Hee Kyung Chang),류총일(Chong Il Yoo) 대한정형외과학회 2003 대한정형외과학회지 Vol.38 No.4