비디오 흉강경을 이용한 자연기흉의 수술요법

권오춘,안욱수 대구효성가톨릭 대학교 1997 연구논문집 Vol.54 No.2

Primary spontaneous pneumothorax has an annual incidence of 9 cases per 100,000 populations, especially high incidence in young adults. Thoracoscopic surgery is not new, but its applications to chest surgery have been more increasing with advanced video technology and instrumentation. We performed 15 cases of bullectomy using video-assisted thoracoscopy(VATS) for patients of pneumothorax. The mean age of patients was 25.1±7.6 years old, 105.5±40.1 minutes of mean operation times, and 3.2±1.9 days of postoperative tube indwelling time. Postoperative complications were persistent air leakage in one case, which was converted to open thoracotomy later, and recurrence of pneumothotax in one case. Video-assisted thoracoscopic bullectomy is effective alternative to thoracotomy for treatment of pneumothorax in terms of short hospital stay, less morbidity, low rate of recurrence, less pain, and good cosmetic results. But objective comparison with mini-thoracotomy will be needed in many aspects.

Flowable Composite Resin의 미세변연누출 및 전단결합강도

박성준,오명환,김오영,이광원,엄정문,권혁춘,손호현 대한치과보존학회 2001 Restorative Dentistry & Endodontics Vol.26 No.4

조혈모세포이식 후 골성장인자의 변화 및 골대사에 미치는 영향 : Impact on Bone Mineral Metabolism

백기현,오은숙,오기원,이원영,김혜수,권순용,한제호,강무일,차봉연,이광우,손호영,강성구,김춘추 대한내분비학회 2002 Endocrinology and metabolism Vol.17 No.5

연구배경: 각종 장기이식의 시행이 많아지고 이식 후 생존율이 증가함에 따라 이식 후 합병증에 대한 관심 또한 높아지고 있다. 조혈모세포이식 후에도 다양한 내분비적 합병증이 발생할 수 있으며 골격에 대한 합병증도 문제점으로 대두되고 있다. 조혈모세포 이식 후 발생하는 골소실에는 이식 후 초기의 골형성 저하와 골흡수 증가가 중요한 역할을 담당하리라고 추측되는데 이러한 골재형성불일치(biochemical uncoupling)에 골 성장인자들이 미치는 영향에 대해서는 알려진 바가 없다. 본 연구에서는 조혈모세포이식 전, 후로 말초 혈액에서 IGF-I, FGF-2, M-CSF같은 성장인자의 변화를 알아보고, 이들 성장인자의 변화가 조혈모세포이식 후의 골형과 골흡수에 미치는 영향 및 이식 후 발생되는 골량 소실과의 연관성을 확인해 보고자 하였다. 방법: 여러 가지 혈액질환으로 인해 동종 골수이식을 시행 받은 환자들을 전향적으로 관찰하였으며 이식 전 및 이식 후 1주, 2주, 3주, 4주 및 3개월, 6개월 1년에 말초 혈액에서 골교체표지자를 측정하였다. 이식 전 및 이식1년 후에 요추골 및 대퇴골 골밀도를 측정할 수 있었던 36명의 환자들을 대상으로 냉동 보관되어 있던 혈청을 이용하여 IGF-I, FGF-2 및 M-CSF를 시기별로 측정하였으며 이들 성장인자와 골교체표지자의 변화 및 골밀도 변화 사이의 상관관계를 확인하였다. 결과: 골흡수 표지자인 혈청 ICTP는 이식 전에 비해 이식 후 4주까지 점차 의의 있게 증가하다가 이후 6개월까지 더욱 증가한 후 감소하였다. 골형성 표지자인 osteocalcin은 이식 후 3주까지는 점차 감소하다가 이후 증가하여 이식 후 3개월 및 6개월에 기저치보다 통계적으로 유의하게 증가한 후 감소하였다. 혈청 IGF-I과 FGF-2는 각각 이식 후 3주 및 1주까지 의미있게 감소하다가 이후 증가하였으며 혈청 M-CSF는 이식 후 1주째에 기저치에 비해 의미 있게 증가하였다가 이후 기저치로 회복되었다. 이식 1년 후 평균 요추부 골밀도는 5.2% 감소하였고 평균 근위대퇴골 골밀도는 11.6% 감소하였다. 이식 전 및 이식 후 3주에 측정한 IGF-I과 같은 시기에 측정한 오스테오칼신 사이에 유의한 상관관계가 관찰되었으며 이식 후 3주째의 M-CSF와 골흡수표지자인 M-CSF 사이에서 의미 있는 양의 상관관계를 관찰할 수 있었다. 이식 후 3주 및 3개월에 IGF-I이 낮은 환자일수록 이식 1년 후 근위대퇴골에서의 골소실이 많은 것으로 분석되었다. 결론: 조혈모세포이식 후 발생하는 골소실에는 기존에 알려진 기저질환의 영향, 성호르몬의 감소, 면역억제의 투여, 골수기질세포와 조골세포의 손상 및 이식초기 사이토카인의 변화이외에도 골성장인자가 관련이 있음을 확인하였고, 이는 이식 후 발생되는 골량소실에 중요한 역할을 할 것이라고 사료된다. Background: A loss of bone mass is usually detected after a bone marrow transplantation (BMT), especially during the early post-transplant period. We recently reported that enhanced bone resorption following a BMT was related to both the steroid dose and the increase in IL-6. We also suggested damage to the marrow stromal microenvironment, by myoablation, partly explains the impaired bone formation following a BMT. It is well known that some growth factor play important role in bone growth and osteogenesis. However, the pathogenetic role of bone growth factors in post-BMT bone loss is unknown and data on the changes in the growth factors, in accordance with bone turnover markers and bone mineral density (BMD) changes are scarce. We investigated changes in bone growth factors such as IGF-I (Insulin-like growth factor-I), fibroblast growth factor-2 (FGF-2) and Macrophage colony stimulating factor (M-CSF), during the post-BMT period, and assessed whether the growth factor changes influenced the bone turnover and post-BMT bone loss. The present study is the first prospective study to describe the changes in bone growth factors following a BMT. Methods: We prospectively investigated 110 patients undergoing a BMT, and analyzed 36 patients (32.4±1.3 years, 17 men and 19 women) whose BMDs were measured before, and 1 year after, the BMT. The serum biochemical markers of bone turnover were measured before, 1, 2, 3 and 4 weeks, 3 and 6 months, and 1 year, after the BMT. The serum, FGF-2, IGF-I and M-CSF levels were measured before and 1 and 3 weeks, and 3 months after the BMT. The correlation between the changes of growth factors and various bone parameters was analyzed. Results: The mean bone losses in the lumbar spine and total proximal femur, calculated as the percentage change from the baseline to the level at 1 year, were 5.2(p<0.05) and 11.6%(p<0.01), respectively. the serum type I carboxyterminal telopeptide(ICTP), a bone resorption marker, increased progressively until 6 months after the BMT, but thereafter decreased, to the base value after 1 year. Serum osteocalcin, a bone formation marker, decreased progressively, until 3 weeks after the BMT but then increased transiently, and finally returned to the base level at 1 year. The serum IGF-I and FGF-2 also decreased progressively until 3 weeks 1 week after the BMT, respectively, then increased to the base values at 3 months. The serum M-CSF increased briskly at 1 week post-BMT, then decreased to the base level. There were positive correlations between the percentage changes from the baseline proximal femur BMD and the IGF-I levels 3 weeks and 3 months (r=0.52, p<0.01, r=0.41, p<0.05) post BMT. A significant correlation was found between the IGF-I and osteocalcin levels pre-BMT, and 3 weeks after the BMT. Another positive correlation was found between the M-CSF and the ICTP levels at 3 weeks post BMT (r=0.54, p<0.05). Conclusion: In conclusion, there were significant changes in the serum IGF-I, FGF-2 and M-CSF levels in the immediate post-BMT period, which were related to a decrease in bone formation and loss in the proximal femoral BMD during the year following the BMT (J Kor Soc Endocrinol 17:664∼674, 2002).

Flowable 및 microfill 복합레진으로 충전된 제 5급와동에서 load cycling 전,후의 미세변연누출 비교

강석호,김오영,오명환,조병훈,엄정문,권혁춘,손호현 大韓齒科保存學會 2002 Restorative Dentistry & Endodontics Vol.27 No.2

Low-viscosity composite resins may produce better sealed margins than stiffer compositions (KempScholte and Davidson, 1988; Crim, 1989). Flowable composites have been recommended for use in Class V cavities but it is also controversial because of its high rates of shrinkage. On the other hand, in the study comparing elastic moduli and leakage, the microfil had the least leakage (Rundle et al. 1997). Furthermore, in the 1996 survey of the Reality Editorial Team, microfills were the clear choice for abfraction lesions. The purpose of this study was to evaluate the microleakage of 6 composite resins (2 hybrids, 2 microfills, and 2 flowable composites) with and without load cycling. Notch-shaped Class V cavities were prepared on buccal surface of 180 extracted human upper premolars on cementum margin. The teeth were randomly divided into non-load cycling group (group 1) and load cycling group(group 2) of 90 teeth each. The experimental teeth of each group were randomly divided into 6 subgroups of 15 samples. All preparations were etched, and Single bond was applied. Preparations were restored with the following materials (n=15) : hybrid composite resin [Z250(3M Dental Products Inc. St.Paul, USA), Denfil(Vericom, Ahnyang, Korea)], microfil [Heliomolar RO(Vivadent, Schaan, Liechtenstein), Micronew(Bisco Inc. Schaumburg, IL, USA)], and flowable composite[AeliteFlo(Bisco Inc. Schaumburg, IL, USA), Revolution(Kerr Corp. Orange, CA, USA)]. Teeth of group 2 were subjected to occlusal load (100N for 50,000 cycles) using chewing simulator(MTS 858 Mini Bionix Ⅱ system, MTS Systems Corp., Minn, USA). All samples were coated with nail polish 1mm short of the restoration, placed in 2% methylene blue for 24 hours, and sectioned with a diamond wheel. Enamel and dentin/cementum margins were analyzed for microleakage on a sclale of 0 (no leakage) to 3 (3/3 of wall). Results were statistically analyzed by Kruskal-Wallis One way analysis, Mann-Whitney U-test, and Student-Newmann-Keuls method. (p=0.05) Results: 1. There was significantly less microleage in enamel margins than dentinal margins of all groups. (p<0.05) 2. There was no significant difference between six composite resin in enamel margin of group 1. 3. In dentin margin of group 1, flowable composite had more microleakage than others but not of significant differences. 4. There was no significant difference between six composite resin in enamel margin of group 2. 5. In dentin margin of group 2, the microleakage were R>A=H=M>D>Z. But there was no significant differences. 6. In enamel margins, load cycling did not affect the marginal microleakage in significant degree. 7. In dentin margins, load cycling did affect the marginal microleakage only in Revolution. (p<0.05)

노화가 인체 중간엽 줄기세포로부터 조골세포로의 증식 및 분화에 미치는 영향

백기현,태현정,오기원,이원영,조정기,권순용,강무일,차봉연,이광우,손호영,강성구,김춘추 대한내분비학회 2003 Endocrinology and metabolism Vol.18 No.3

연구배경: 일반적으로 골다공증과 연관된 위험인자로는 연령, 폐경, 약물, 불충분한 칼슘섭취, 만성질환 및 운동부족 등이 있는데, 특히 노화가 진행할수록 골밀도가 감소하는 것은 잘 알려져 있다. 노화와 관련하여 진행되는 골소실은 조골세포 및 전구조골세포의 기능적 결핍에 의한 골형성의 감소가 주요한 요인으로 여겨지고 있다. 그 동안 연령이 조골모 세포의 양과 조골모 세포로부터 성숙조골세포로의 분화 및 증식에 미치는 영향에 대한 일부 보고들이 있었으나 아직 일치된 견해는 없는 형편이다. 방법: 다양한 연령의 사람으로부터 골수를 채취, 중간엽 줄기세포가 포함된 단핵세포를 분리한 후 조골세포로 분화하기 좋은 조건하에서 배양하였다. 대상군은다시 젊은군과 노령군으로 구분하여 다양한 변수를 비교 분석하였다. 일차배양에서는 CFU-F를 계수하여 골수내 중간엽 줄기세포의 수를 추산하였고, 칼슘측정을 통하여 기질의 무기화 정도를 비교하였다. 계대배양후 이차배양에서는 시기별로 알카리성 포스파타제 활성도를 측정하고 오스테오칼신 mRNA의 발현을 관찰하여 젊은군과 노령군 사이의 증식능 차이를 비교하였다. 또한 이차배양 시기별로 MTT 측정을 하여 양군간에 증식능 차이가 있는지 알아보았다. 결과: 1. 일차배양 15일째에 평균 CFU-F의 수는 젊은군에서 유의하게 많았다(젊은군 148.3±28.9, 노령군 54.3±9.1, p=0.02). CFU-F의 평균면적은 젊은군에서 넓은 경향을 보였으나 통계적으로 유의하지는 않았다. 2. 일차배양 17일 경과 후 양군간에 기질 칼슘 침착정도는 유의한 차이를 보이지 않았다(젊은군 103.6±50.6, 노령군: 114.0±56.5, p=NS). 3. 이차배양 10일째에 젊은군에서 알카리성 포스파타제 활성도가 고령군에 비해 유의하게 높았다(젊은군: 935.5±115.0 U/mg, 노령군: 578.4±115.7U/mg,p.0.05). 고령군에서는 시간 경과에 따른 변화가 미약했으며 전반적으로 알카리성 포스파타제의 활성도가 젊은군에 비해 낮았다. 4. 이차배양도중 오스테오칼신 mRNA의 발현은 배양시기별로 젊은군에 비해 고령군에서 더 낮은 경향을 관찰할 수 있었다. 5. 이차배양 10일과 15일에 젊은군에서 노령군보다세포증식이 유의하게 증가된 양상을 보였다(10앓 젊은군 0.73±0.05, 노령군 0.58±0.04, p=0.05, 15일; 젊은군 0.80±0.05, 노령군 0.70±0.03, p=0.05).결론: 이상의 연구에서 저자들은 노령군에서 젊은군보다 골수 내 중간엽줄기세포의 수가 적고, 노령군에서 유래한 전구조골세포의 성숙조골세포로의 증식 및 분화가 젊은군 보다 감소해 있는 것을 관찰할 수 있었다. Background: Osteoblasts originate from osteoprogenitor cells in bone marrow stroma, termed mesenchymal stem cells (MSCs) or bone marrow stromal cells. Each MSC forms colonies (colony forming units-fibroblasts [CFL-Fs]) when cultured ex vivo. There are some reports about the age-related changes of the number and osteogenic potential of osteoprogenitor cells, but any relationship has not been clearly established in humans. In this study, we counted MSCs using CFU-Fs count and examined the proliferative capacity and differentiation potential of osteoprogenitor cells. Finally, we analyzed how these parameters varied with donor age. Methods: Bone marrow was obtained from the iliac crest of young (n=6, 27.2±8.6 years old) and old (n= 10, 57.4k6.7 years old) healthy donors. Mononuclear cells, including MSCs, were isolated and cultured in osteogenic medium. In primary culture, we compared the colony-forming efficiency of MSCs between the two groups and determined the matrix calcification. When primary culture showed near confluence, the cells were subcultured. Alkaline phosphatase activity, osteocalcin expression by RT-PCR and proliferative potential by MTT assay were examined by the time course of secondary culture. Results: At the 15th day of primary culture, the mean number of CFU-Fs was significantly higher in the younger donors (young: 148.3±28.9, old: 54.3±9.1, p=0.02) and the mean size of CFL-Fs was also larger in the younger donors than the older donors. However, matrix calcification was not different between the two groups (young: 103.6±50.6, old: 114.0±56.5, p=NS). In secondary culture, alkaline phosphatase activities were significantly lower in the older donors. The younger donors showed peak alkaline phosphatase activity at day 10, while the older donors didn't showed a remarkable peak (young: 935.5±115.OU/mg, old: 578.4±115.7U/mg, p<0.05). Total cell number as a proliferative index increased progressively during the secondary culture and a significantly greater cell number was noted in the younger donors. Osteocalcin expression was generally upregulated in the younger donors, but this was not statistically significant. Conclusion: Our study shows that the number of osteoprogenitor cells is decreased during aging and that the proliferative capacity and differentiation potential of osteoprogenitor cells seem to be reduced during aging (J Kor SOC Endocrinol 18:296-305, 2003).

톨루엔 취급 근로자의 ALDH2 Genetic Polymorphism에 따른 뇨중 마뇨산 배설량

김창윤,정종학,권오춘,김성용,이중정,주리 大韓産業醫學會 1997 대한직업환경의학회지 Vol.9 No.2

In this study we evaluated the effects of the genetic polymorphism of aldehyde dehydrogenase2 (ALDH2) on the toluene metabolism and determined biological exposure indices(BEIs) for toluene by the genotypes of ALDH2. The study subject were 77 men workers who are handling toluene in a video tape manufacturing factory and a textile company. Through the face-to-face interview, the information about smoking and drinking behavior was obtained. For determination of ALDH2 polymorphism, 5ml of venous blood sample was obtained from each subject after informed consent. DNA was extracted from the buffy coat and ALDH2 genotyping were performed using a polymerase chain reaction(PCR) method. The genotype of ALDH2 was classified into the homozygous genotype of normal ALDH2(NN), and the heterozygous genotype of normal and inactive ALDH2(ND), and homozygous genotype of an inactive ALDH2(DD). The concentration of hippuric acid (HA), the main metabolite of toluene, was determined in urine specimens collected at the end of shift, corrected with creatinine(HA/C), and compared with BEI for toluene, which is 2.5 g/g creatinine. The personal exposure level of toluene were monitored, using personal air sampler and analyzed by gas chromatography. The frequencies of the three genotypes in this study subject were, NN : 45 (58.4%), ND : 26 (33.8%) and DD : 6 (7.8%), and frequencies of the genotypes in the middle or heavy toluene exposure workers were not significantly different from those in the mild toluene exposure workers. The frequencies of the DD type of ALDH2 was lower among alcohol drinkers than among non-drinkers. The urinary HA concentration of DD group was significantly lower than that of the NN or ND group, which suggests that the HA formation from toluene decreased in DD group. Regression lines were used to estimate the BEIs of the NN, ND, and DD groups. NN : y = 0.0085x + 0.23, r = 0.90 ND : y = 0.0074x + 0.21, r = 0.85 DD : y = 0.0041x + 0.82, r = 0.83 The three regression lines revealed that the estimated urinary HA concentration of NN, ND, and DD groups at 377 mg/㎥ toluene (TLV-TWA) exposure were 3.43, 3.00, and 2.37g/g than that of the ACGIH BEI (2.5 g/g creatinine) ; however, the HA level of DD group was lower than the BEI. These results suggest that the ACGIH BEI is not adequate to estimate the toluene exposure of the NN, ND and DD groups at the same time. Based upon these results, a new BEI for ALDH2 deficient workers may be necessary.

H₂O/LiBr+HO(CH₂)₃OH계 공냉형 이중효용 흡수식 냉방시스템의 사이클 해석

권오경,문춘근,윤정인,Kwon, Oh-Kyung,Moon, Choon-Geun,Yoon, Jung-In 대한기계학회 1999 大韓機械學會論文集B Vol.23 No.2

A cycle analysis was achieved to predict the characteristics by comprehensive modeling and simulation of an air-cooled, double-effect absorption system using a new $H_2O/LiBr+HO(CH_2)_3OH$ solution. The simulation results showed that the new working fluid may provide the crystallization limit 8% higher than the conventional $H_2O/LiBr$ solution. With a crystallization margin of 3wt%(weight%), the optimal solution distribution ratio was found in the range of 36 to 40%. Variation of cooling air Inlet temperature has a sensitive effect on the cooling COP and corrosion problem. The simulation of heat exchangers with UA value revealed that the absorber and the evaporator are relatively important for an air-cooled system compared with the condenser and the low temperature generator. The effect of cooling air flow rate, circulation weak solution flow rate and chilled water inlet temperature were also examined. The new working fluid may provide the COP approximately 5% higher than the conventional $H_2O/LiBr$ solution.

"부로일러" 飼料에 있어 油脂 添加에 對한 飼養試驗과 經濟性 分析에 關한 硏究 : 同熱量 水準의 飼料에서 on an Isocaloric basis

吳世正,金春洙,權恒基 건국대학교 1971 學術誌 Vol.12 No.1

The usage of tallow to replace corn on an isocaloric basis upto 9 percent level did not improve the growth over the control chicks and no significant difference was. also observed in the feed efficiency of control group from those of the experimental groups of receiving 3,6 and 9 percent tallow. This is also true for the values of among the experimental groups. Through the observations of these results. it is concluded that tallow as a feed ingredient can be added to the diet upto 9 percent level on an isocaloric basic, without deteriorating it's untritive value. With an estimated price of tallow 70 won per kg. weight, the addition of tallow for the place of corn on an isocaloric basis resulted in higher prices of the feeds of added tallow. Since no improvement on the feed efficiency was affected by the addition tallow, it is assumed that the economy of broiler production is very much depended upon the cost of tallow rather than the value of tallow itself. Based on the current market price of corn 25.28 won per kg. weight, it is estimated that tallow as a feed ingredient is to bepriced at less than 65.73 won per kg. weight to bring about broiller production cost economically possible.

Si3N4-304 스테인리스강 브레이징접합체의 계면반응생성물과 파단면의 조직적 특징

권오양,강춘식,이우천 대한금속재료학회(대한금속학회) 1993 대한금속·재료학회지 Vol.31 No.3

The Si₃N₄/STS304 joints vacuum-brazed with four types of Cu-Ag-Ti brazing alloy was shearing-tested. For the joints showing interfacial fracture the position, morphology and microchemistry of reaction products on the fracture surface of Si₃N₄- side was investigated by scanning electron microscope (SEM) equipped with energy-dispersive spectrometer (EDS). Types and fratures of interfacial reaction products observed on the fracture surface are following : first, titanium silicide that is a layer structure and contains the network-shaped microcrack ; second, iron titanium silicide that is a granular (grain size is about several hundred nanometer in dia.) and layer structure ; third, Fe-Ti compounds can be classified into Fe-Ti-Si-Cr and Fe-Ti-Cr systems, the former is the angular-type grains (of several micrometer in size) and the latter is a compound showing the brittle cleavage fracture ; fourth, Cu-Ti-Fe compound that is a granular (grain size is about several hundred nanometer in dia.) and layer structure. All the compound consisted of a granular structure showed a intergranular fracture. Interfacial fracture of Si₃N₄/STS 304 joints is classified into three types as following ; first, seperation (fracture) at the interface between Si₃N₄and titanium silicide ; second, complex fracture varying the path through each interface between reaction products ; third, a part of fracture occur in the second form, but a large part of fracture occur through the inner of reaction products. The shear strength of Si₃N₄/STS304 joints showing three types of interfacial fracture is below 42 ㎫, average 180 and 202 ㎫ respectively. Therefore, the more the strength of joints is high, the more fracture occur through the inner of reaction products than at the interface between reaction products.

Experience of 21 Totally Laparoscopic Donor Hepatectomies for Adult Liver Transplant Recipients

Choon Hyuck David Kwon,Jae-Won Joh,Jong-Man Kim,Gyuseong Choi,Jinyong Choi,Wontae Cho,Seunghwan Lee,Byonggon Na,Dongkyu Oh,Junhyung Ha,Suk-Koo Lee 한국간담췌외과학회 2014 한국간담췌외과학회 학술대회지 Vol.2014 No.4