Epstein-Barr 바이러스 감염과 관련된 우두모양물집증 모양(HV-Like) 발진

조광현 ( Kwang Hyun Cho ) 대한피부과학회 2011 大韓皮膚科學會誌 Vol.49 No.9

Hydroa vacciniforme (HV) is a rare self-limiting disease characterized by vesicles and crust formation after sun exposure. However, cases with HV-like eruptions and severe systemic symptoms have also been described. It had been regarded as a different entity from typical HV. But latent Epstein-Barr Virus (EBV) infection has also been detected in typical HV patients and the possibility has been suggested that typical HV and atypical HV are variants within the same disease spectrum of EBV-associated lymphoproliferative disorders, which ranges from typical HV as a benign pole to severe HV progressing to hematologic malignancy as a malignant pole. Chronic active Epstein-Barr virus infection (CAEBV) is an atypical illness associated with serologic evidence of persistent EBV infection. The extremely high levels of EBV measured in affected tissue or peripheral blood are the most recently proposed diagnostic criteria. Recently, we found high levels of EBV in the peripheral blood of patients with EBV-associated HV-like eruptions. (Korean J Dermatol 2011;49(9):773~779)

토마토 뿌리조직에서 분리한 마이크로솜 이온펌프의 특성

조광현,사공정,김영기 ( Kwang Hyun Cho,Jung Sakong,Young Kee Kim ) 한국응용생명화학회 1998 Applied Biological Chemistry (Appl Biol Chem) Vol.41 No.2

Microsomes of tomato roots were prepared and the activities of microsomal ATPases were measured in order to understand the molecular mechanisms of various ion transports. The activities of plasma membrane H^+-ATPase and vacuolar H^+-ATPase were evaluated to ∼30% and ∼38% of total microsomal ATPase activity by using their specific inhibitor, vanadate and nitrate (NO₃^-), respectively. The inhibitory effects of vanadate and NO₃^- were additive and the simultaneous additions of these two inhibitors decreased the total activity up to 50∼70%. The microsomal ATPase activity was regulated key pH and the maximal activity was obtained at pH 7.4. The activity of microsomal ATPase was increased by K^+ up to ∼30% at the concentration of K^+ above 10 mM. However, the K^+- induced increase in the activity was Completely inhibited by the simultaneous addition of Na^+. To identify the ATPase activity regulated by K^+, the effects of specific inhibitors were measured. Vanadate and NO₃^- inhibited total ATPase activity by 27% and 32% in the absence, of K^+ and by 27% and 40% in the presence of 120 mM K^+, respectively. These results suggest that K^+ increases the activity of NO₃^--sensitive vacuolar H^+-ATPase but not that of vanadate-sensitive plasma membrane H^+-ATPase since vanadate has no effect on K^+-induced increase in ATPase activity. The microsomal ATPase activity was also decreased by increasing Ca^(2+) concentration. Interestingly, NO₃^- blocked the Ca^(2+)-induced inhibition of microsomal ATPase activity; however, vanadate had no effect. These results imply that vacuolar H^+-ATPase is activated by K^+ and inhibited by Ca^(2+).

다중외적연관성규칙을 이용한 불필요한 입력변수 제거에 관한 연구

조광현,박희창,Cho, Kwang-Hyun,Park, Hee-Chang 한국데이터정보과학회 2011 한국데이터정보과학회지 Vol.22 No.5

의사결정나무는 데이터마이닝의 대표적인 알고리즘으로서, 의사결정 규칙을 도표화하여 관심대상이 되는 집단을 몇 개의 소집단으로 분류하거나 예측을 수행하는 방법이다. 일반적으로 의사결정나무의 모형 생성 시, 입력 변수의 수가 많을 경우 생성된 의사결정모형은 복잡한 형태가 될 수 있고, 모형 탐색 및 분석에 있어 어려움을 겪기도 한다. 이때 입력변수들 간의 내재적인 관련성은 없으나, 외적 변수에 의하여 각 변수가 우연히 어떤 다른 변수와 연결됨으로써 관련성이 있는 것으로 나타나는 것을 종종 볼 수 있다. 이에 본 논문에서는 의사결정나무 생성 시, 입력 변수에 대한 외적 관계를 파악할 수 있는 다중외적연관성규칙을 이용하여 의사결정나무 생성에 불필요한 입력변수를 제거하는 방법을 제시하고 그 효율성을 파악하기 위하여 실제 자료에 적용하고자 한다. The decision tree is a representative algorithm of data mining and used in many domains such as retail target marketing, fraud detection, data reduction, variable screening, category merging, etc. This method is most useful in classification problems, and to make predictions for a target group after dividing it into several small groups. When we create a model of decision tree with a large number of input variables, we suffer difficulties in exploration and analysis of the model because of complex trees. And we can often find some association exist between input variables by external variables despite of no intrinsic association. In this paper, we study on the removal method of unnecessary input variables using multiple external association rules. And then we apply the removal method to actual data for its efficiencies.

주변 조건부 변수에 의한 연관성 규칙 생성에 관한 연구

조광현,박희창,Cho, Kwang-Hyun,Park, Hee-Chang 한국데이터정보과학회 2012 한국데이터정보과학회지 Vol.23 No.1

연관성규칙은 대용량 데이터베이스에서 각 항목들 간의 관련성을 찾아내는 기법이다. 현재 연관성규칙의 효율성을 개선하기 위하여 많은 연구자들에 의하여 제약 기반 연관성규칙의 연구가 활발하게 진행되고 있다. 연관성규칙 생성 시, 종종 많은 규칙들을 발견할 수 있다. 이들 규칙 중에서 변수들 간에 우연히 관련성이 높게 나타나는 경우가 존재할 수 있고 주변 조건부 변수 (매개변수, 외적변수)에 의하여 직접적인 관련성이 없는 규칙을 발견할 수도 있으며, 그 규칙은 간접적 해석만 가능하므로 의미가 없는 것으로 판단 할 수 있다. 이에 본 연구에서는 연관성 규칙에서 주변 조건부 변수를 고려한 연관성 규칙 생성에 관하여 연구하고자 하며, 이를 실례를 통하여 고찰하였다. 본 연구의 결과를 적용함으로써 연관성 규칙에서 의미 없는 규칙을 찾을 수 있으며, 변수들 간의 관련성을 보다 정확하고 명확하게 이해할 수 있을 것이다. Association rule mining searches for interesting relationships among items in a given database. Currently, study of the constraint-based association rules are underway by many researchers. When we create relation rule, we can often find a lot of rules. Of this rules, we can find rule that direct relativity by marginally conditional variables (intervening variable, external variable) does not exist. In such a case, this association rule can be considered insignificant. In this study, we want to study for association rules creation using marginally conditional variable. The result of this study can find meaningless association rules. Also, we can understand more exactly the relationships between variables.

토마토 뿌리조작에서 분리한 마이크로솜의 Ca2+ 흡수 특성

조광현(Kwang Hyun Cho),김영기(Young Kee Kim) 한국응용생명화학회 1999 Applied Biological Chemistry (Appl Biol Chem) Vol.42 No.2

In order to characterize the property of Ca^(2+) transport in plant cell, microsomes were prepared from the roots of tomato and microsomal ^(45)Ca^(2+) uptake was measured. When 1 mM vanadate, a selective inhibitor of P-type ATPases, 50 mM NO₃^-, a specific inhibitor of vacuolar H^+-ATPase, and both of these inhibitors were treated, the microsomal ^(45)Ca^(2+) uptakes were inhibited by 20, 33 and 47%, respectively. The inhibitory effects of these two inhibitors were investigated by using a protonophore, gramicidin. When the chemical gradient of H^+ was relieved by gramicidin, the uptake was decreased by 30%, implying the presence of Ca^(2+)/H^+ antiporter in the microsomal membrane. In the ^(45)Ca^(2+) uptake experiment, the effect of gramicidin was independent of vanadate-induced inhibition. However, when the activity of vacuolar H^+-ATPase was inhibited by NO₃^-, the effect of gramicidin was severely decreased. Meanwhile, thapsigargin, a specific antagonist of ER/SR-type Ca^(2+)-ATPase, inhibited the microsomal ^(45)Ca^(2+) uptake and the maximum inhibitory effect was obtained at 10 μM. The effect of thapsigargin was blocked by NO₃^- and gramicidin, but not by vanadate. These results imply that vanadate directly inhibits the activity of Ca^(2+)-ATPase; however, NO₃^- and thapsigargin block the activity of Ca^(2+)/H^+ antiporter by inhibiting the vacuolar H^+-ATPase. In conclusion, the microsomal ^(45)Ca^(2+) uptakes are mediated by two major enzymes, Ca^(2+)-ATPase and Ca^(2+)/H^+ antiporter in tomato root tissue.

젖소군의 유생산 수준별 이질성 분산 보정

조광현,이준호,박경도,Cho, Kwang-Hyun,Lee, Joon-Ho,Park, Kyung-Do 한국데이터정보과학회 2014 한국데이터정보과학회지 Vol.25 No.4

본 연구는 젖소의 검정성적, 총 502,228개를 이용하여 젖소군 분산에 대한 이질성을 비교 검증하고 동질적인 분산을 유도하기 위하여 수행되었다. 유량, 유지방량과 유단백량에 대한 유전력은 각각 0.28, 0.26과 0.24로 추정되었으며, 출생년도별 평균 육종가는 HV (heterogenous variance) 모형의 추정치가 animal 모형의 것보다 일괄적으로 낮게 나타났다. 국제유전능력평가 기준에 적용된 씨수소 545두에 대한 유량, 유지방량, 유단백량의 평균 육종가는 각각 453.54kg, 10.75kg과 14.33kg이었으며, 이질성이 보정된 경우의 평균 육종가는 각각 432.06kg, 10.15kg과 13.40kg으로서 모든 유생산형질에서 보정된 자료의 육종가 평균이 일괄적으로 낮게 나타났다. animal 모형에서 데이터세트 I과 II사이의 표현형 상관계수는 유량 0.839, 유지방량 0.821, 유단백량 0.837이었으며, HV 모형에서는 유량 0.841, 유지방량 0.820, 유단백량 0.836으로 두 모형에서 거의 유사한 결과를 나타내었다. animal 모형과 HV 모형으로 비교한 결과 유량에서 ${\theta}$값은 15.157에서 16.105, 유지방량은 -0.227에서 -0.196으로 증가하였으나 유단백량의 경우 0.630에서 0.586으로 감소하였다. This experiment was conducted to compare heterogeneity for the variance in dairy cattle population and to induce homogeneity of variance using 502,228 performance test records of dairy cattle. The estimates of heritability for milk yields, fat yields and protein yields were 0.28, 0.26 and 0.24, respectively and the estimate of average breeding value by birth year was lower in HV (heterogenous variance) model than in animal model, collectively. The average breeding values of milk yields, fat yields and protein yields for 545 sire bulls applicable to the criteria of interbull MACE programme were 453.54kg, 10.75kg and 14.33kg, respectively and when the heterogeneity was adjusted they were 432.06kg, 10.15kg and 13.40kg, respectively, which were lower in all milk traits collectively. In animal model, coefficients of phenotypic correlation between dataset I and II were 0.839 in milk yields, 0.821 in fat yields, and 0.837 in protein yields, while in HV model, they were 0.841 in milk yields, 0.820 in fat yields, and 0.836 in protein yields, showing similar results in 2 models. When compared using animal model and HV model, the regression coefficient for ratio of number of daughters by calving year of milk yields increased from 15.157 to 16.105 and that of fat yields increased from =0.227 to =0.196, but that of protein yields decreased from 0.630 to 0.586.

Bazin의 경결홍반

조광현 ( Kwang Hyun Cho ) 대한피부과학회 2010 대한피부과학회지 Vol.48 No.12

Erythema induratum of Bazin (EIB) belongs to a group of diseases characterized by inflammatory nodules of the leg which primarily involve the lower legs. EIB is considered to be a reactive disorder related to several etiologic factors. In Korea, most dermatologists accept the tuberculosis as one of the most common etiology of EIB. As the number of EIB cases is decreasing in Korea in accordance with the decreased incidence of tuberculosis, EIB can be easily mistaken for any of the disease that produces chronic nodular eruptions on the legs. In Korea, important factors to make a correct diagnosis of EI include clinicopathologic observations coupled with the identification of hypersensitivity to tuberculous antigen and successful treatment of anti-tuberculous medication. (Korean J Dermatol 2010;48(12):1045∼1051)

염산 흡입 후 발생한 Reactive Airways Dysfunction Syndrome (RADS) 1례

조광현,김승환,조영순,이한식,박준석,Cho, Kwang-Hyun,Kim, Seung-Hwan,Cho, Young-Soon,Lee, Hahn-Shick,Park, Joon-Seok 대한임상독성학회 2005 대한임상독성학회지 Vol.3 No.1

A previously healthy 57-year-old woman with dyspnea and wheezing presented to the emergency department a few minutes after exposure to unknown gas from mixing bleach (sodium hypochlorite) and cleaning agent (hydrochloric acid) at work place. Initial physical examination revealed severe wheezing on both whole lung fields, but the chest radiograph was normal. Arterial blood gas analysis showed only moderate hypoxemia. The patient was treated with oxygen, $\beta$adrenergic bronchodilators, antihistamines and corticosteroids, after then symptoms were improved. And the patient discharged against medical advice. We report a rare case of reactive airways dysfuntion syndrome from chlorine gas exposure.

광노화에 따른 피부의 조직학적 변화

조광현 ( Kwang Hyun Cho ),이미경 ( Mi Kyung Lee ),조성진 ( Sung Jin Jo ),김규한 ( Kyu Han Kim ),박경찬 ( Kyoung Chan Park ),은희철 ( Hee Chul Eun ),정진호 ( Jin Ho Chung ) 대한피부과학회 2003 대한피부과학회지 Vol.41 No.6

N/A Background : In white people, a distinction between intrinsic aging and photoaging has been well documented in histologic studies. However, no histological studies to date have attempted to announce morphological changes with photoaged skin of Koreans. Objective : Our purpose was to compare the histologic change with advancing age between exposed skin and nonexposed skin of Koreans. Methods : Twenty-one male volunteers between 20 and 80 years of age were recruited. The histochemical and immunhistochemical studies were performed with the skin obtained from face and buttock. Results : 1. With advancing age, there was a decreasing tendency in the epidermal thickness. However, there was no difference between exposed skin and non-exposed skin. 2. Density of dopa-positive melanocytes was much higher in the face than in the buttock at all ages. Decline of melanocyte density with advancing age is not prominent in the facial skin. 3. In the facial skin, accumulation of thickened degraded elastic fibers and a decrease in collagen fibers are evident with advancing age. In the facial skin, increase of acid mucopolysaccharides is also found with advancing age. Conclusion : Koreans, the histologic changes in the skin with photoaging are distinct from those in the skin with intrinsic aging. (Korean J Dermatol 2003;41(6) : 754~760)

홀스타인 젖소의 원유내 acetone과 β-hydroxybutyrate acid 함량에 영향을 미치는 환경요인

조광현,조충일,이준호,박경도,Cho, Kwang-Hyun,Cho, Chung-Il,Lee, Joon-Ho,Park, Kyung-Do 한국데이터정보과학회 2015 한국데이터정보과학회지 Vol.26 No.3

본 연구는 젖소의 검정기록, 378,086개를 이용하여 케토시스 진단 지시형질로 이용되는 유량내 아세톤과 ${\beta}$-히드록시부틸산의 함량에 영향을 미치는 환경요인을 분석하였다. 형질별 목장, 비유단계, 산차, 착유시간 및 월령에 대한 유의성 검정 결과 모든 요인들에서 고도의 유의성 (p < 0.01)이 나타났으며, 가장 큰 환경요인은 비유단계였다. 1회 착유량, 아세톤과 ${\beta}$-히드록시부틸산의 함량에 대한 월령의 1차 회귀계수는 모두 정 (+)의 관계, 2차 회귀계수는 부 (-)의 관계를 나타내었으며, 비유 2단계 (36~65일) 비유량의 최소자승평균은 19.06kg으로 비유말기에 비하여 6.51kg 높았다. 아세톤과 ${\beta}$-히드록시부틸산의 함량에 대한 최소자승평균은 비유 1단계 (5~35일)에서 각각 0.1929mM/L과 0.0742mM/L로 가장 높았으며, 착유일수에 따라 감소하다가 비유말기 소폭 증가하는 경향을 나타내었다. 1산에 대한 아세톤과 ${\beta}$-히드록시부틸산의 함량의 최소자승평균은 각각 0.1414mM/L과 0.0522mM/L로 2차산 이상의 평균보다 높았으며, 오후착유에 대한 아세톤과 ${\beta}$-히드록시부틸산의 함량의 최소자승평균이 각각 0.1372mM/L과 0.0534mM/L로 오전착유보다 일괄적으로 높게 나타났다. Using 378,086 lactation records on dairy cattle, environmental factors influencing acetone and ${\beta}$-hydroxybutyrate acid contents in raw milk which are used as ketosis diagnosis indicator traits were analyzed in this experiment. Significance testing was conducted on farm, lactation stage, parity, milking time and month of age by traits. The results of this experiment indicated that there was a highly significant (p < 0.01) difference in all factors and lactation stage was the most significant factor. Linear regression coefficients of month of age on daily milk yields and acetone and ${\beta}$-hydroxybutyrate acid contents were all positive, while their quadratic linear regression coefficients were negative. Least square means for milk yield at second lactation stage (36~65 days) was 19.06kg which was higher than that of late lactation stage by 6.51kg. Least square means for acetone and ${\beta}$-hydroxybutyrate acid contents at the first lactation stage (5~35 days) were highest (0.1929mM/L and 0.0742mM/L, respectively), and there was a trend that they decreased as the milking progressed, but increased slightly at the late stage of milking. However, least square means for acetone and ${\beta}$-hydroxybutyrate acid contents at the first parity were 0.1414mM/L and 0.0522mM/L, respectively, which were higher than the average milk yield after the second parity. Least square means for acetone and ${\beta}$-hydroxybutyrate acid contents of PM milk yield (0.1372mM/L and 0.0534mM/L, respectively) were higher than those of AM milk yield collectively.