질식 분만된 조산아에서 아프가 점수 , 제대 동맥혈 가스분석의 임상적 의의

박지용(Ji Yong Park),정진훈(Jin Hoon Chung),박교훈(Kyo Hoon Park),조용균(Yong Kyoon Cho),최훈(Hoon Choi),김복린(Bok Rin Kim),이홍균(Hong Kyoon Lee),고수진(Su Jin Ko),서정식(Joung Sik Seo),유태환(Tae Hwan Yoo) 대한산부인과학회 1998 Obstetrics & Gynecology Science Vol.41 No.11

N/A Objective: The Apgar score has long been used to determining birth asphyxia and assessing early neonatal status and long-term outcome. Unfortunately, some components of this system depend upon subjective interpretation. Also, although, low Apgar score, Most of newborns are relatively healthy. The objective of our studt is attempt to assure the linical significance of Apgar score and umbilical cord blood gas analysis on assessing status of uncomplicated preterm infants delivered vaginally. Methods: The present study was performed in attempt to compare umbilical arterial blood gas values for uncomplicated preterm infants delivered vaginally with low 1 and 5 minutes Apgar score (<7) with those for term or preterm infant with normal 1 and 5 minutes score (>7), each other, The present study included 82 uncomplicated term infants delivered vaginally and 24 preterm infants. Inclusion criteria of our study is as follows: 1) Singleton neonate with vertex presentation, 2) No congenital malformation, 3) Infants whose mother had no obstetrical and medical complications, 4) Immediately after delivery, umbilical arterial blood was sampled, before first breathing of neonate, 5) Infants applied Apgar score at I minute and again 5 minutes after birth, and 6) Infants whose mothers gestational age was estimated by ultrasonography during first-trimester of pregnancy. The statistical analysis was performed by Mann-Whitney U test and Fishers exact test. Results: 1) There was no significant difference in umbilical arterial blood gas values between uncomplicated preterm infants delivered vaginally with low 1 and 5 minutes Apgar score (<7) and term infants with normal score (>7). 2) There was no significant difference in umbilical arterial blood gas values between uncomplicated preterm infants delivered vaginally with low 1 and 5 minutes Apgar score (<7) and preterm infants with normal score (>7). 3) There was significant difference in frequency of lower Apgar score (<7) between term (2%[2/82]) and preterm infants (38%[9/24]), but not in frequency of acidemia (defined as less than pH 7.2) (28%[23/82] Vs 33%[8/24]). Conclusion: The Apgar score is not a reliable indieator of well-being in preterm neonate. We recommend umbilical arterial blood sampling at delivery of preterm infant with low Apgar score, because umbilical cord blood gas indices on objective means of assessing birth status of the newbarn and more useful than Apgar score in ruling out birth asphyxia.

임신 중기 원인불명 모체혈청 인간 융모성 성선자극호르몬이 상승된 임부에서의 임신 예후

박지용(Ji Yong Park),정진훈(Jin Hoon Chung),고수진(Su Jin Ko),박교훈(Kyo Hoon Park),서정식(Jung Sik Seo),유태한(Tae Hwan Yoo),조용균(Yong Kyoon Cho),최훈(Hoon Choi),김복린(Bok Rin Kim),이홍균(Hong Kyoon Lee) 대한산부인과학회 1998 Obstetrics & Gynecology Science Vol.41 No.11

N/A Objective: Our purpose was to determine whether unexplained elevation in maternal serum human chorionic gonadotropin without abnormal elevation in matemal serum alpha-fetoprotein (MSAFP) in the second trimester may be associated with adverse pregnancy outcomes. Methods: Between January 1997 and December 1997, we evaluated 906 pregnant women undergoing second trimester triple marker screening tests who delivered at our hospital. Multiple pregnancy, fetal anomaly, intrauterine fetal death before 20 completed weeks of gestational age, insulin dependent diabetes mellitus and maternal serum alpha-fetoprotein level greater than 2.0 multiple of the median (MoM) were excluded fiom the study. Seventy-two women with hCG level greater than 2.0 MoM were included in the study group while 809 women with hCG level less than 2.0 MoM served as the control group. Adverse pregnancy outcomes were obtained from hospital delivery records and neonatal records. Statistical analysis were performed by students t-test and chi square test. Results: Women with unexplained elevation of human chorionic gonadotropin level showed increased risks for intrauterine growth retardation (P<0.01) and pregnancy induced hypertension (P<0.05). There were no significant differences between study and control groups with respect to preterm delivery, placental abruption, fetal anomaly and intrauterine fetal death. Conclusion: Unexplained elevation of human chorionic gonadotropin in the second trimester was associated with intrauterine growth retardation and pregnancy induced hypertension.

태반조기박리가 동반된 임신성 고혈압 임산부와 정상혈압 임산부에서의 주산기 예후에 대한 비교 분석

박지용(Ji Yong Park),정진훈(Jin Hoon Chung),조용균(Yong Kyoon Cho),최훈(Hoon Choi),김복린(Bok Rin Kim),이홍균(Hong Kyoon Lee),유태환(Tae Hwan Yoo),고수진(Soo Jin Ko),박교훈(Gyo Hoon Park),서정식(Jeong Sik Seo) 대한산부인과학회 1998 Obstetrics & Gynecology Science Vol.41 No.11

N/A Objective: The objective of this study was to compare perinatal outcomes of pregnancy-induced hypertensive and normotensive women experiencing abruptio placentae, Our hypothesis is that pregnancy-induced hypertensive women have a less favorable perinatal outcome than do normotensive women. Methods: Women with the diagnosis of abruptio placentae delivered between August 1,1989 and December 1,1996, composed the study group (n-92) in this case-control study. The women with abruptio placentae were divided according to their hypertensive (n 37) or normotensive (n 55) status. Maternal and neonatal medical records were reviewed and abstracted for demographic variables, antepartum complications, delivery route, abruptio placentae grade, neonatal gender, birth weight, Apgar score and perinatal mortality. We compared these perinatal outcome variables between the pregnancy-induced hypertensive and normotensive pregnant women. Results: The incidence of abruptio placentae was 0.35%. The two groups of woman wne similar with regard to age and parity. Abruptio placentae grades 2 occurred more often in hypertensive women (P=0.0053). Pregnancy-inducedhypertensive women were similar to normotensive women with regard to antenatal complications. The mean gestational age of delivery, delivery route, neonatal weight and sex were similar between two groups of women. Neonates from pregnancy-induced hypertensive women were no more likely to have low 1 and 5-minute Apgar score or to die than those from normotensive women. Statistical analysis was performed with two-tailed independent t-test and Kruskal-Wallis analysis. Conclusion: Although pregnancy-induced hypertensive women experiencing abruptio placentae are more likely to have grade 2 abruptio placentae with fetal distress, the overall perinatal outcome was not significantly different from that of normotensive women experiencing abruptio placentae.

포장 콘크리트

정진훈(Jin-Hoon Jeong),박상구(Sang-Goo Park),홍승호(Seung-Ho Hong),남정희(Jeong-Hee Nam) 한국콘크리트학회 2010 콘크리트학회지 Vol.22 No.1

섬유보강 아스팔트 포장 부착 전단강도 개선방안 연구

박상구(Park Sang Gu),김기현(Kim Ki Hyun),권수안(Kwon Soo Ahn),정진훈(Jeong Jin Hoon) 대한토목학회 2009 대한토목학회논문집 D Vol.29 No.5D

본 연구에서는 반사균열 및 러팅을 저감시키는 것으로 알려진 섬유보강 아스팔트 포장의 성능을 극대화하기 위한 방안을 찾기 위하여 3곳의 구간에서 현장 시험시공을 실시하였다. 섬유보강 아스팔트의 부착 전단강도에 영향을 미칠 수 있는 시공 도중 발생 가능한 문제점을 정의하고 시험시공 시 이에 맞는 시공조건을 의도적으로 만들어 주었다. 시험시공 직후와 약 1년이 지난 후 시공 상태가 양호한 위치와 불량한 위치에서 각각 코어를 채취하고 부착 전단강도 실험을 수행하여 그 결과를 비교 분석하였다. 이를 통하여 섬유보강 아스팔트의 성능을 향상시키기 위하여 현장에서 지켜야 할 만한 규정을 제안하였다. Test constructions were performed at 3 sites to investigate ways for maximizing performance of geogrid-reinforced asphalt pavements known to reduce reflection cracking and rutting. Problems during construction operation which can affect bonding shear strength of the geogrid-reinforced asphalt pavements were defined and the construction conditions were intentionally made during the test constructions. Both immediately and 1year after the test constructions, cores were obtained from positions with good and bad construction conditions and then bonding shear strength tests were performed to be compared each other. Rules to be kept at construction sites were suggested to improve performance of the geogrid-reinforced asphalt pavements.

재령초기 콘크리트포장 줄눈거동에 미치는 온도의 영향

최기효,정진훈,천성한,박문길,Choi. Ki-Hyo,Jeong. Jin-Hoon,Chun. Sung-Han,Park. Moon-Gil 한국방재학회 2007 한국방재학회 학술발표대회논문집 Vol.2007 No.1

The temperature variation of concrete pavement at early-age significantly affects the initiation and movement of joint cracks. For this analysis, we have built on IIA(Incheon International Airport) concrete pavement construction zone, and we measured the temperature and movement of the concrete slabs by using thermocouples, moisture sensors, V/W strain gages, and Demac discs. The analysis results showed that pavement`s temperature significantly affected the joint movement. The widths of the joint cracks increased at evening and early in the morning when the temperature dropped but, those decreased in the day time when the temperature rose because of the effect of thermal expansion of the concrete slabs. The movements of the joints where the cracks never developed showed opposite trend to the cracked joints. 콘크리트포장의 줄눈의 초기균열발생과 움직임에 영향을 주는 중요한 인자는 콘크리트 내부의 초기온도이므로 이를 측정하고 분석하는 것은 매우 중요하다. 이를 연구하기 위해 인천국제공항 포장공사 지역에 써머커플과 습도센서, 진동형스트레인게이지, 디멕디스크 등을 설치하였다. 초기균열 거동은 디멕게이지를 이용하여 측정하였고, 초기균열 및 줄눈분 균열은 육안으로 확인 하였다. 분석결과, 콘크리트포장의 온도는 줄눈거동에 크게 영향을 주는 것으로 나타났다. 줄눈에 발생한 균열의 폭은 콘크리트슬래브의 열팽창의 영향으로 온도가 하강하는 야간이나 새벽에 증가하고, 온도가 상승하는 주간에는 줄어드는 것을 확인할 수 있었다. 균열이 발생하지 않은 줄눈의 거동은 이와는 반대의 경향을 나타내었다.

반강성 덧씌우기 포장의 기능적 및 구조적 성능 평가

박강용(Park Kang Yong),이재준(Lee Jae Jun),권수안(Kwon Soo Ahn),정진훈(Jeong Jin Hoon) 대한토목학회 2010 대한토목학회논문집 D Vol.30 No.3D

반강성 포장은 공극률이 큰 개립도 아스팔트 혼합물의 공극에 시멘트 페이스트를 침투시켜 아스팔트 포장의 연성과 콘크리트 포장의 강성을 동시에 이용하는 포장형식이다. 반강성 포장은 콘크리트 포장에 비해 평탄성이 좋고 주행에 의한 진동이나 소음을 저감할 수 있으며, 아스팔트 포장에 비해 소성변형이 적고 온도저감 효과가 있는 것으로 알려져 있다. 본 연구에서는 반강성 덧씌우기 포장을 시험시공하여 반강성 포장의 온도저감 효과를 조사하였고 시편을 제작하여 옥외에서 온도 및 중량을 측정하여 반강성 포장의 온도저감 및 보수 효과를 확인하였다. 상용 3차원 유한요소해석 프로그램인 Abaqus 6.8로 반강성 포장과 아스팔트 포장을 구조해석하여 하중재하 위치에서의 수평 및 연직방향 응력과 변형률을 비교하고 다층탄성해석 프로그램 Bisar 3.0으로 검증하였다. 구조해석 결과를 바탕으로 피로균열을 예측하여 반강성 포장과 아스팔트 포장의 공용성을 비교하였다. Semi rigid pavement is a pavement type using advantages of both flexibility of asphalt pavement and rigidity of concrete pavement by infiltrating cement paste into voids of open graded asphalt mixtures. The semi rigid pavement has better smoothness and smaller driving vibration or noise comparing to the concrete pavement, and has smaller permanent deformation and has temperature falling effect comparing to the asphalt pavement. The temperature falling effect were investigated at a semi rigid overlay pavement test section, and the temperature falling and water retaining effects were verified by measuring the temperature and weight of specimens at a housetop. Horizontal and vertical stresses and strains were compared by structural analysis of the semi rigid pavement and asphalt pavement using the Abaquser o, a commercial 3D finite element analysis program. The results were verified by Bisar 3.0, a multi-layered elastic analysis program. Performance of the semi rigid pavement and asphalt pavement were compared by predicting fatigue cracking based on the structural analysis results.

줄눈균열 유도장치를 사용한 콘크리트 포장의 줄눈거동

박문길(Park Moon Gil),최기효(Choi Ki Hyo),남영국(Nam Young Kug),정진훈(Jeong Jin Hoon) 대한토목학회 2008 대한토목학회논문집 D Vol.28 No.1D

콘크리트 포장의 줄눈은 초기 콘크리트 슬래브에 건조수축과 온도변화에 의한 무작위 균열이 발생하지 않도록 해주어 도로포장의 공용성 향상에 기여한다. 하지만 콘크리트가 충분히 양생되기 전에 수행된 줄눈 절단 작업은 줄눈 주변의 콘크리트에는 미세균열 등의 손상을 발생시키고 이로 인하여 반복적인 교통 및 환경하중에 의한 줄눈부의 파손이 장기적으로 발생한다. 본 연구에서는 이러한 인위적인 줄눈 절단작업 때문에 발생할 수 있는 줄눈부 파손을 감소시키기 위하여 선행연구를 통해 개발된 100㎜, 150㎜, 220㎜ 높이의 줄눈균열 유도장치와 다양한 깊이를 갖는 균열유도 홈을 시험시공 구간에 설치하고 줄눈균열의 발생과 거동을 약 5개월에 걸쳐 조사하였다. 그 결과, 줄눈균열 유도장치의 높이가 높을수록 균열유도 효과가 높은 반면 줄눈균열의 거동은 큰 것으로 나타났다. 향후 추가적인 조사와 줄눈균열 유도장치의 개선을 통하여 균열 유도 효율을 높이고 줄눈의 성능을 향상시켜야 할 것으로 판단되었다. Joint of concrete pavement contributes to improvement of pavement performance by preventing occurrence of random cracking due to drying shrinkage and temperature changes of concrete slabs at early age. However, saw-cutting operations performed prior to sufficient concrete hardening develop micro-cracking of the concrete near the joints, which may develop to long-term distresses due to repetitious traffic and environmental loadings. To reduce the distresses, the joint crack inducers with heights of 100 ㎜, 150 ㎜, and 220 ㎜ and the joint cracking slots with various depth were installed at a test section to investigate occurrence of the joint cracks and their behaviors over 5 months. As the results, higher efficiency of the crack inducing and larger behavior of the joint cracks were observed for the taller joint crack inducer. Higher efficiency of the crack inducing and improvement of the joint performance are warranted by additional investigation and reformation of the joint crack inducer.

태아의 염색체의 수적 이상을 유발하는 모계 위험인자로서 5, 10-Methylentetrahydrofolate Reductase (MTHFR C677T)와 Methionine Synthase Reductase (MTRR A66G) 유전자의 다형성 연구

김도진(Do Jin Kim),김신영(Shin Young Kim),박소연(So Yeon Park),김진우(Jin Woo Kim),김문영(Moon Young Kim),한정렬(Joung Yeol Han),양재혁(Jae Hyug Yang),안현경(Hyun Kyong Ahn),최준식(Jun Seek Choi),정진훈(Jin Hoon Chung),류현미(Hyun Me 대한의학유전학회 2008 대한의학유전학회지 Vol.5 No.2

목적: 다운증후군을 비롯한 염색체의 수적이상은 태아의 유산이나 정신박약의 가장 큰 요인으로 알려져 있다. 이에 본 연구에서는 엽산 대사에 관련된 효소의 다형성(MTHFR C677T, MTRR A66G)을 조사하여 태아의 염색체 수적이상과 유전적인 연관성을 알아보고자 한다. 대상 및 방법: 염색체 수적이상이 확인된 태아를 임신한 37명의 산모와 유산이나 비정상적인 임신을 한 경험이 없고 2명 이상의 건강한 아이를 출산한 78명의 여성을 정상군으로 하여 혈액으로부터 DNA를 추출하고 PCR-RFLP를 이용하여 각 지역의 다형성 여부를 확인하였다. 결과: MTHFR C677T 유전자형은 CC, CT, TT에 대해 각각 30.7%, 48.7%, 20.6%였으며, 환자군에서 각각 37.8%, 48.6%, 13.5% 였다. 정상군과 환자군 사이 모든 조합에서 유의한 차이를 보이지 않았다. 대립유전자의 비율 역시 대조군과 환자군에서 각각 44.9%, 37.8%였으며, 통계적 유의한 차이는 없었다. MTRR A66G 유전자형은 대조군에서 AA, AG, GG에 대해 각각 50.0%, 46.1%, 3.9%였으며, 환자군에서는 각각 13.5%, 81.1%, 5.4%였다. MTRR의 정상 유전자형인 AA와 이형접합성 변이형인 AG 유전자형을 비교하였을 때 유의한 차이를 보였으며(OR: 6.5, 95% CI: 2.3-18.6, P<0.05), 정상이 아닌 모든 다른 유전자형(AG/GG)과 비교하였을 때에도 역시 유의한 차이를 보였다(OR: 6.4, 95% CI: 2.3-18.1, P<0.05). 결론: 본 연구에서는 MTHFR 677번째 염기의 다형성은 염색체 비분리로 인한 태아 염색체의 수적이상과 연관성이 없는 것으로 확인하였으나, MTRR 66부위의 경우 염기의 다형성이 태아 염색체의 수적이상을 유발하는 유전적 요소로서의 가능성을 제시하고 있다. Purpose: Aneuploidy is the cause of diseases such as Down syndrome or Edward syndrome and, more generally, is a major cause of mental retardation and fetal loss. The purpose of this study was to evaluate the association between MTHFR (C677T) or MTRR (A66G) polymorphisms and fetal aneuploidy. Materials and Methods: Data was collected from 37 women who had a fetus with aneuploidy (cases) and 78 women who had previously delivered at least two healthy children without aneuploidy and did not have a history of miscarriage or abnormal pregnancy (controls). The MTHFR (C677T) or MTRR (A66G) polymorphisms were analyzed by PCR-restriction fragment length polymorphism assay. Results: The frequencies of the MTHFR 677 CC, CT, and TT genotypes were 30.7%, 48.7%, and 20.6% in the control group and 37.8%, 48.6%, and 13.5% in the case group, respectively. There were no significant differences in genotype frequencies between the two groups. For the MTRR A66G polymorphism, the frequencies of the AA, AG and GG genotypes were 50%, 46.1%, and 3.9% in the control group and 13.5%, 81.1%, and 5.4% in case group, respectively. The frequency of the MTRR AG mutant was significantly increased in the case group, with an odds ratio of 6.5 (95% CI: 2.3-18.6, P<0.05). Conclusion: The results of this study suggest that mother carriers with the MTRR G allele have an increased risk of fetal aneuploidy, while the MTHFR T allele is not associated with increased risk of fetal aneuploidy. The MTRR A66G polymorphism may be a risk factor for producing a child with chromosomal aneuploidy.

콘크리트 슬래브와 보조기층 사이의 마찰특성 조사

임진선(Lim Jin Sun),박문길(Park Moon Gil),남영국(Nam Young Kug),정진훈(Jeong Jin Hoon) 대한토목학회 2009 대한토목학회논문집 D Vol.29 No.6D

본 연구에서는 슬래브와 보조기층 간의 마찰 특성을 조사하기 위하여 국내 콘크리트 포장에 주로 사용되는 린 콘크리트, 쇄석, 아스팔트 보조기층에 대하여 마찰력 실험을 실시하였다. 이 외에도 분리막 사용 여부와 보조기층의 습윤 상태를 실험 변수로 사용하였다. 슬래브에 40㎜/hour의 속도로 수평하중을 가한 1차 하중 재하 시와 안정화 상태(2차 및 3차) 및 습윤 상태(4차)에서의 슬래브의 수평변위와 마찰계수를 측정하였다. 1차 하중재하 시 린 콘크리트, 아스팔트, 쇄석, 그리고 분리막을 사용한 보조기층 순으로 최대 마찰계수가 컸으며, 안정화 상태에서는 아스팔트, 쇄석, 린 콘크리트 그리고 분리막을 사용한 보조기층 순으로 크게 측정되었다. 분리막을 사용한 보조기층은 습윤 상태에 의한 영향이 거의 없었으나 분리막을 사용 하지 않은 쇄석 및 아스팔트 보조기층은 습윤 상태로 인하여 마찰계수가 감소하였다. 향후 슬래브의 두께와 아스팔트의 온도 민감성이 미치는 영향에 대한 추가 마찰력 실험이 수행될 것이다. 그리고, 실험 결과를 이용한 구조해석을 통하여 슬래브와 보조기층 간의 마찰특성이 콘크리트 포장의 거동 및 공용성에 미치는 영향을 조사할 계획이다. In this study, a series of push-off tests for lean concrete, aggregate, asphalt subbases mainly used in Korea were performed to investigate the friction characteristics between the slab and subbase layers. Use of separation membrane and wet condition of subbase were other parameters in the tests. Horizontal displacements of the slabs and friction coefficients were measured at 1st loading, stable condition (2nd and 3rd loadings), and wet condition (4th loading) by applying 40㎜/hour horizontal loadings. Larger maximum friction coefficients were measured in order of the lean concrete, asphalt, aggregate, and subbases using the separation membrane at lst loading, and in order of the asphalt, aggregate, lean concrete, and subbases using the separation membrane at stable and wet conditions. The friction coefficients of the aggregate and asphalt subbases which did not used the separation membrane decreased by the wet condition while the subbases using the separation membrane were not affected. Additional push-off tests for effects of slab thickness and temperature sensitivity of asphalt will be performed. And, effects of the friction characteristics between the slab and subbase layers on behavior and performance of concrete pavements will be investigated by structural analyses using the test results.