공정이상발생시 GOAL - TREE 를 이용한 대처조작 자동합성

박경찬,안대명,황규석 ( Kyoung Chan Park,Dae Myung An,Kyu Suk Hwang ) 한국화학공학회 1996 화학공학의이론과응용 Vol.2 No.2

백반증 - 326예의 임상적 고찰 -

박경찬,윤재일,이유신 ( Kyoung Chan Park,Jai Il Youn,Yoo Shin Lee ) 대한피부과학회 1988 大韓皮膚科學會誌 Vol.26 No.2

We evaluated the clinical manifestations of 326 patients of vitiligo who had visited Seoul National University Hospital. The results were as follows : 1) There were 141 males (43.3%) and 185 females (56.7%). 2) The mean age of onset was 19.6 years (male : 18.3 years, female : 20.6 years). 3) The mean age at the first visit wss 23.9 years (male : 22.5 years, female : 24.9 years). 4) Duration of disease was less than 2 year in 156 patients (47.9%). 5) The most common site of initial involvement was face (36.2%). The common sites of involvement were face (55.2), abdomen (32.5%), neck (26.7%) and scalp (24.8%) in decreasing order of frequency. 6) There were 167 cases (51.2%) of generalized type, 118 cases (36.2%) of localized type, 31 cases (9.5%) of dermatomal type and 10 cases (3.1) of halo nevus. The most frequent site of dermatomal type was neck. Gray hair was noted in 91 cases (27.9%) and mucosal involvement was present in 43 cases (13.2%). 7) Family history was obtained in 24 cases (7.4%). Koebner phenomenon was present in 48 cases (14%). There were no precipitating factors in 309 cases (94.8%) prior to development of vitiligo. 8) The associated diseases were 1 csse of thyroiditis and 3 cases of alopecia areata.

Basic steps to approach with pigmentary disease

박경찬 ( Kyoung Chan Park ) 대한피부과학회 2013 대한피부과학회 학술발표대회집 Vol.65 No.2

Pigmentary disease is difficult to treat because it is not only a pigmentary abnormality but also additional abnormalities which contribute to increased melanogenesis. Genetic pigmentary conditions may have abnormal cells which should be removed for the treatment. However, pigmentary abnormality by reactive response of normal melanocytes should be treated conservatively. In addition, vascular component is usually found with pigmentary conditions. Then, it is not clear what is the real target of treatment when dealing with pigmentary conditions, These findings suggest that it will be most important to find out every problems which contribute to pigmentary conditions. First of all, pigmentary abnormality can be divided into congenital and acquired conditions. Congenital condition such as cafe au lait spot is a collection of abnormal clone of cells. If genetic manipulation is not possible, these problems need to be removed by physical methods, However, dermal melanosis seems to be different. It is not clear whether Ota`s nevus is composed of normal or abnormal melanocytes. Even if these cells are normal cells, there is no method to remove these cells by medical methods. Then, physical methods are necessary to treat these conditions. By the way, melasma is a most common pigmentary condition. It is characterized by brown pigmentation. Theoretically, it can easily be removed by laser treatment. Unfortunately, this aggressive treatment will induce intense post inflammatory pigmentation. It can be speculated that normal melanocytes will respond actively if normal cells are damaged by strong injury. It is well known that post-inflammaotry hyperpigmentation will resolve spontaneously. But, melasma usually persist and recurr even after treatment. It is not completely known but there are several reports which showed dermal degeneration, basement membrane abnormality, and vascular dilatation in dermal part of melasma. And increased c-kit expression and VEGF expression seems to be factors which induced persistent pigmentation in melasma lesions, Thus, it is very important to find our underlying problems of the pigmentary conditions. In addition, hypo and depigmented conditions is caused by melanocyte dysfunction or death. Then, protection strategy against cell death is most important in the treatment of vitligo. However, there are really diverse kinds of hyper and hypopigmentary conditions and these conditions are overlapping in many occasions. Thus, correct diagnosis is important in the treatment of pigmentary conditions, Finally, I`d like to say that correct diagnosis is rather finding out all diverse mixed conditions which are observed simultaneously.

Suppression of miR135b increases the proliferative potential of normal human keratinocytes

박경찬 ( Kyoung Chan Park ) 대한피부과학회 2013 대한피부과학회 학술발표대회집 Vol.65 No.2

Background: Cell fate is regulated by the activation and repression of specific genes and microRNAs (miRNAs) are a class of post-translational regulators of gene expression. Psoriasis is a hyperproliferative skin disorder and it has been reported that the stratified epidermis expresses miR135b, which suggests that miR135b is related with epidermal keratinization. Previously, we isolated populations of epidermal cells according to their ability to adhere to type IV collagen (Rapidly adhering (RA) cells; epidermal stem cells, slowly adhering (SA) cells: differentiated cells). Objectives: The effects of miRNAs on epidermal stem cells were investigated. Methods: Type IV collagen-coated dishes were prepared and a subpopulation of those cells was selected by their ability to adhere to type IV collagen-coated dishes. To test the effects of miR135b, cultured keratinocytes were transfected with miR135b mimic. In addition, miR135b was suppressed to study whether inhibition of miR135b can delay differentiation of keratinocytes. At every passage, transfection was repeatedly performed, and a portion of cells were harvested for cell counting, RNA extraction, and protein extraction. The levels of p63, known as a potential stem cell marker, were also checked. To confirm the proliferative effects of ib-miR135b, skin models were constructed using ib-miR135b transfected cells. After 13 days, sections were stained. Finally, to know whether type IV collagen is a target of miR135b, database was searched. It was found that there is a binding site of hsa-miR135b in 3`UTR region of COL4A3 gene. Protective sequence was designed to inhibit binding of miR135b in 3`UTR region of COL4A3 gene. Results: miR135b was significantly increased in SA cells. RT-PCR analysis showed that transfection of ib-miR135b is effective in suppression of miR135b. Cumulative cell numbers showed a big difference. A colony assay showed that ib-miR135b transfected cells showed a higher colony forming ability. At the 9th passage, ib-miR135b transfected cells reached ca 5 X 1010 cells. However, mock-transfected cells expanded only to 1.6 X 1010 cells. In addition, mock- transfected cells showed large vacuoles earlier than ib- miR135b transfected cells. Our observations suggest that the inhibition of miR135b is effective in preventing degenerative changes of epidermal cells. The levels of p63 were also consistently higher in ib-miR135b transfected cells. These results correlate well with the increased proliferative potential of ib-miR135b transfected cells. In skin model study, the number of p63-positive and PCNA-positive cells was higher in the ib-miR135b model. These findings suggested that the inhibition of miR135b may prolong the stemness and proliferative potential of epidermal keratinocytes. Then, niche environment of epidermal cells were examined and the expression of type IV collagen were increased in the ib-miR135b model. Furthermore, the levels of α6 integrin and β1 integrin are increased in the ib-miR135b model. In monolayer culture, expression of COL4A3 was increased by inhibition of miR135b as shown in skin model study. When cells were transfected with miR135b mimic, they became larger. Furthermore, protective sequence of miR135b abolished these effects. RT-PCR analysis also showed that miR135b mimic decreased the expression levels of COL4A3 and protective sequence of miR135b reversed these effects. These findings suggested that type IV collagen is a target of miR135b and important in maintaining the proliferative potential of keratinocytes. Conclusion: Type IV collagen is a target of miR135b and that the inhibition of miR135b may improve the microenvironment and increase the proliferative potential of basal cells. Our results showed the role of miR135b in epidermal keratinocytes and may provide a way to manipulate stem cell fate in the skin.

Azathioprine 치료 중 유방 편평세포암종이 발생한 크론병 1예

박경찬 ( Kyoung Chan Park ),주동욱 ( Dong Uk Ju ),허성욱 ( Seong Wook Heo ),류정일 ( Jung Ii Ryu ),조주연 ( Ju Youn Cho ),김의정 ( Eui Jung Kim ),오훈규 ( Hoon Kyu Oh ),김은영 ( Eun Young Kim ) 대한소화기학회 2012 대한소화기학회지 Vol.60 No.6

Azathioprine (AZA) treatment in transplant or autoimmune patients and subsequent appearance squamous cell carcinomas at various sites, particularly skin and cervix, has shown a close relationship. However, it remains uncertain whether this is true for the patients with Crohn`s disease. We report a case of squamous cell carcinoma of the breast occurred in a 35-year-old female with Crohn`s disease taking AZA. She was first diagnosed with Crohn`s disease 10 years ago and has taken AZA with 5-aminosalicylic acid (5-ASA) on regular follow up in gastrointestinal department for 9 years. She had no family history of breast cancer. She visited breast cancer clinic due to incidentally found right breast mass. A mastectomy on the right breast was performed and 6.3×5.5 cm mass was removed. The mass was microscopically proven to be poorly differentiated squamous cell carcinoma with focal keratin pearl formation. At age of 25, she was first diagnosed with active Crohn`s disease. 5-ASA and corticosteroid induced remission. Then, steroid was tapered off and AZA was maintained at 1 mg/kg due to leukopenia at higher dose. She stopped taking AZA at her discretion during her two pregnancies and reported total of 67 months of AZA medication on her breast cancer diagnosis.

Symposium 5-2 (SYP 5-2) : Dive into melanocytes: Its cellular environment

박경찬 ( Kyoung Chan Park ),( Dong Seok Kim ),( Hye Ryung Choi ) 대한피부과학회 2014 대한피부과학회 학술발표대회집 Vol.66 No.2

Individual melanocytes are surrounded by keratinocytes. Thus, melanocytes-keratinocytes interactions are key factors in the fate of melanocytes. For example, UV can affect melanocytes through the keratinocytes-induced cytokines. After binding to melanocytes receptor, these signals will be delivered to nucleus via signal transduction pathway. To understand the pathogenesis of pigment diseases, complete understanding of this process is vital. Furthermore, melanocytes are located at upper side of basement membrane. Because basement membrane is key extracellular matrix of keratinocytes stem cells, these findings suggest that melanocytes and keratinocytes will receive the similar influences from the basement membrane status. Then, relationship with basement membrane will be discussed. In addition, melanocytes will receive signals from fibroblasts or extracellular matrix of dermis. Among these, DKK1 is well known to inhibit melanogenesis. But, there are numerous factors are thought to be related with melanocytes fate in the skin. In this presentation, key factors of melanocytes environment will be discussed.

Dietary Supplementation of Catechin Inhibits UVB-induced Oxidative Damage in BALB/c Mice

박경찬 ( Kyoung Chan Park ),전상은 ( Sang Eun Jeon ),최스미 ( S Mi Choi ),박경애 ( Kyoung Ae Park ),권선방 ( Sun Bang Kwon ) 대한피부과학회 2002 초록집 Vol.40 No.20

Research Cafe : Pigmentary disorders and translational research

박경찬 ( Kyoung Chan Park ),( Dong Seok Kim ),( Hye Ryung Choi ) 대한피부과학회 2015 대한피부과학회 학술발표대회집 Vol.67 No.2

간염의 피부 소견에 대한 임상적 고찰

박경찬 (Kyoung Chan Park) 대한피부과학회 1986 大韓皮膚科學會誌 Vol.24 No.6

A clinical observations of skin lesions was performed on 189 patients suffering from hepatitis who were admitted to the Department of Internal Medicine in Armed. Forces General Hospital. The result were as follows: 1) Cutaneous manifestations were found in 143 patients(75.7%). 2) Purpuric lesion was found in 62 patients(32. 8%), spider angioma in 57 patients(30%), palmar erythema in 40 patients(21.2%), melanosis in 37 patients(19. 6%) acne in 22 patients(11,6%), jaundice in 15 patients(7.9%) and striae distensae in 14 patients(7.4%). 3) Among rnelanosis, there were 14 patients with diffuse pigmentation, 3 patients with localized pigmentation, 14 patients with palmar crease pigmentation, 10 patients with accentuation of freckling and 11 patients with chloasma. 4)Common cutaneous manifestations in acute hepatitis were spider angioma (21. 4%), palmar erythema (21.4%) and purpuric lesion (17.9%), in chronic hepatitis, purpuric lesion(44.8%) spider angioma(37%) and melanosis(24.8%).

과초산 처리 목재 표면 에폭시 수지 함침에 따른 특성 분석

박경찬 ( Kyoung-chan Park ),김병호 ( Byeongho Kim ),박한나 ( Hanna Park ),박세영 ( Se-yeong Park ) 한국목재공학회 2021 한국목재공학회 학술발표논문집 Vol.2021 No.1

아세트산과 과산화수소의 반응에 의해 생성되는 과초산은 강력한 산화제로서 최근 코로나 확산에 따라 살균용 목적으로 많이 이용되고 있다. 이러한 과초산은 목재에 처리할 경우 강력한 산화 반응에 의하여 주성분 중 리그닌을 분해하는 것으로 잘 알려져 있다. 목분에 처리하여 섬유와의 분리에 사용될 수 있을 뿐 아니라, 이방성 목재 특성을 유지하면서 선택적으로 리그닌을 분해시켜 다공성 구조를 가질 수 있는 재료로써 기능성 소재화 연구에도 널리 적용될 수 있다. 또한, 변색을 일으키는 리그닌의 제거를 통해 자외선에 의한 열화의 차단 기능도 가질 수 있다. 본 연구에서는 목재 표면에 과초산 처리를 적용하여 리그닌을 선택적으로 제거하고자 하였다. 타 선행 연구와 달리 목재 내부 구조를 유지하면서 표면에 대한 처리만 적용하였다. 온도, 시간 및 농도 조건을 달리한 표면처리 변화를 관찰하였으며, 조건에 따른 처리 깊이를 단면별로 비교하였다. 추가적으로 내열성, 내수성, 내약품성이 뛰어난 열경화성 수지인 에폭시 수지를 표면에 함침하여 표면개질에 따른 특성을 평가하고자 하였다. 공시재료로 참오동나무 (Paulownia tometosa)를 실험에 사용하였으며, 표면 화학처리를 위해 과초산 용액(Peracetic acid, PAA) 및 증류수를 1:1, 1:2 및 1:3 (v/v)으로 혼합하여 각각 3, 6시간 동안 70 ℃에서 처리하였다. 반응 후 에폭시 수지를 진공가압함침하여 침투 깊이와 관능기 변화를 확인하였다. 과초산의 농도가 높고 처리 시간이 길수록 깊은 침투 깊이를 보였고, 밝은 재색을 나타내었다. 상세 연구결과는 구두발표 자료로 보고하고자 한다.