Bifidobacterium longum and Galactooligosaccharide Improve Skin Barrier Dysfunction and Atopic Dermatitis-like Skin

Kim Sukyung,Han Song-Yi,Lee Jinyoung,Kim Na-Rae,Lee Bora,Kim Hyunmi,Kwon Mijeoung,Ahn Kangmo,Noh Youngbae,Kim Sang Jong,Lee Phyrim,Kim Dongki,Kim Byung Eui,김지현 대한천식알레르기학회 2022 Allergy, Asthma & Immunology Research Vol.14 No.5

Purpose: The beneficial effects of a combination therapy using Bifidobacterium longum and galactooligosaccharide (GOS) for the treatment of atopic dermatitis (AD) have not been elucidated. Methods: Gene expressions of interleukin (IL)-4 and IL-13 from peripheral blood mononuclear cells and fecal abundance of B. longum from 12-month-old infants were evaluated. Human primary epidermal keratinocytes (HEKs) and hairless mice were treated with B. longum, GOS, B. longum-derived extracellular vesicles (BLEVs), dinitrochlorobenzene (DNCB), or a synbiotic mixture of B. longum and GOS. Expression of epidermal barrier proteins and cytokines as well as serum immunoglobulin E (IgE) levels were analyzed in HEKs and mice. Dermatitis scores, transepidermal water loss (TEWL), epidermal thickness, and fecal B. longum abundance were evaluated in mice. Results: Fecal abundance of B. longum was negatively correlated with blood IL-13 expression in infants. B. longum or BLEVs increased expression of filaggrin (FLG) and loricrin (LOR) in HEKs. B. longum increased the efficacy of GOS to upregulate FLG and LOR expressions in HEKs. Oral administration of GOS increased fecal abundance of B. longum in mice. Oral administration of B. longum attenuated DNCB-induced skin inflammation, abnormal TEWL, AD-like skin, and deficiency of epidermal barrier proteins. Moreover, the combination of B. longum and GOS showed greater effects to improve DNCB-induced skin inflammation, abnormal TEWL, AD-like skin, serum IgE levels, IL-4 over-expression, and the deficiency of epidermal barrier proteins than the administration of B. longum alone. Conclusions: B. longum and GOS improve DNCB-induced skin barrier dysfunction and AD-like skin.

자동차 디젤엔진 내마모 부품개발

김동기(Dongki Kim),김원태(Wontae Kim),김기열(Kiyoul Kim),김찬영(Chanyong Kim),강신재(Shinjae Kang) 한국자동차공학회 2009 한국자동차공학회 지부 학술대회 논문집 Vol.2009 No.10

Materials design and processing development proposed in this research, aims at contributing to low price wear resistant automobile diesel engine parts. Dense bonding layer products were fabricated by solid diffusion bonding method. The hardness and TRS values obtained were 88HRA and 120㎏/㎟, respectively. Finally, teamwork consisting of company, university and research center will give them a chance of learning, processing, theory and applications in machine parts and will help domestic automobile industries internationally competitive.

한국형발사체 추진기관시스템 시험설비(PSTC) 개발 현황

김동기(Dongki Kim),이정호(Jungho Lee),김상헌(Sangheon Kim),김용욱(Yongwook Kim),조기주(Kiejoo Cho),오승협(Seunghyub Oh) 한국추진공학회 2016 한국추진공학회 학술대회논문집 Vol.2016 No.5

본 논문은 한국형발사체 각 단 추진기관시스템의 성능검증을 위해 현재 나로우주센터에 구축중인 추진기관시스템 시험설비의 개발현황에 관한 것이다. PSTC 제1스탠드에서는 1단 추진기관시스템의 수류시험 및 연소시험을, 제2스탠드에서는 2단/3단 추진기관시스템의 수류시험 및 연소시험을 수행할 수 있게 설계하였다. PSTC는 크게 유공압시스템, 제어계측시스템, 테스트스탠드시스템, 후류안전시스템으로 구분되며 각 시스템은 시험 요구조건을 바탕으로 설계 및 개발이 이루어지고 있다. This paper describes the construction and development status of Propulsion System Test Complex (PSTC) for the verification test of each stage’s propulsion system of KSLV-Ⅱ. Separated two test stands are designed for integrated hydraulic tests and combustion tests, one is for the 1st stage propulsion system and the other is for the 2nd/3rd stage propulsion systems. Four systems such as phuemo-hydraulic system, control/measurement system, test stand system, and flame deflector and safety system are being constructed for the PSTC on the basis of the design requirements.

Tumor-suppressor Protein p53 Sensitizes Human Colorectal Carcinoma HCT116 Cells to 17α-estradiol-induced Apoptosis via Augmentation of Bak/Bax Activation

Cho Rong Han(한초롱),Ji Young Lee(이지영),Dongki Kim(김동기),Hyo Young Kim(김효영),Se Jin Kim(김세진),Seokjoon Jang(장석준),Yoon Hee Kim(김윤희),Do Youn Jun(전도연),Young Ho Kim(김영호) 한국생명과학회 2013 생명과학회지 Vol.23 No.10

17α-estradiol (17α-E₂)의 에폽토시스 유도활성에 미치는 종양억제단백질 p53의 조절효과를 조사하고자, 17α-E₂에 의해 유도되는 에폽토시스 현상들을 인체 대장암 세포주 유래 클론인 HCT116 (p53+/+) 및 HCT116 (p53-/-) 세포에서 비교하였다. HCT116 (p53+/+) 및 HCT116 (p53-/-) 세포를 17α-E₂ (2.5~10 μM)로 처리하거나 혹은 HCT116 (p53+/+) 및 HCT116 (p53-/-) 세포를 10 μM 17α-E₂로 시간 별로 처리한 결과, HCT116 (p53+/+)에 있어서는 세포독성과 에폽토시스-관련 sub-G₁ peak의 비율은 처리농도와 시간에 의존적으로 나타났다. 그러나 HCT116 (p53-/-) 세포의 경우는 이러한 현상이 미약하게 나타났다. 17α-E₂에 의해 유도되는 비정상적 유사분열방추사 형성, 중기판 염색체 배열의 미완성, 이에 따른 유사분열정지(G₂/M arrest) 등의 현상은 HCT116 (p53+/+) 및 HCT116 (p53-/-) 세포에서 유사한 수준으로 나타났다. 이에 반해, 17α-E₂에 의해 유도되는 Bak과 Bax의 활성화, 미토콘드리아의 막전위 상실(Δψm loss), 그리고 PARP 분해 등의 현상은 HCT116 (p53-/-) 세포에 비해 HCT116 (p53+/+) 세포에서 훨씬 높은 수준으로 확인되었다. 아울러 17α-E₂로 처리된 HCT116 (p53+/+) 세포에서 확인되는 p53 (Ser-15)의 인산화 및 p53 수준의 증가와 일치하여, 세포 내의 p21및 Bax 수준도 현저히 증가하였다. 이때 17α-E2로 처리된 HCT116 (p53-/-) 세포에서는 p21 및 Bax의 발현수준이 매우 낮았다. 한편, 에폽토시스 억제단백질인 Bcl-2 단백질수준은 HCT116 (p53-/-) 세포에 비해 HCT116 (p53+/+) 세포에서 다소 낮았으나, 이러한 Bcl-2 단백질 수준은 17α-E₂ 처리 후에도 크게 변화하지 않는 것으로 나타났다. 이러한 결과들은 17α-E₂ 처리에 의해 유도되는 에폽토시스 유도 경로의 구성원들의 변화, 즉 비정상적 유사분열방추사 형성 및 이에 따른 유사분열정지(G2/M arrest), 뒤이은 Bak 및 Bax의 활성화, 미토콘드리아의 막전위 상실, 그리고 이에 수반되는 caspase cascade 활성화 및 PARP 분해로 진행되는 에폽토시스 현상들 중에서, Bak 및 Bax의 활성화 단계가 종양억제단백질 p53의 에폽토시스 증진 활성에 의해 양성적으로 조절되는 작용 타켓임을 보여준다. The regulatory effect of the tumor-suppressor protein p53 on the apoptogenic activity of 17α-estradiol (17α-E₂) was compared between HCT116 (p53+/+) and HCT116 (p53-/-) cells. When the HCT116 (p53+/+) and HCT116 (p53-/-) cells were treated with 2.5~10 μM 17α-E₂ for 48 h or with 10 μM for various time periods, cytotoxicity and an apoptotic sub-G₁ peak were induced in the HCT116 (p53+/+) cells in a dose- and time-dependent manner. However, the HCT116 (p53-/-) cells were much less sensitive to the apoptotic effect of 17α-E₂. Although 17α-E₂ induced aberrant mitotic spindle organization and incomplete chromosome congregation at the equatorial plate, G₂/M arrest was induced to a similar extent in both cell types. In addition, 17α-E₂-induced activation of Bak and Bax, Δψm loss, and PARP degradation were more dominant in the HCT116 (p53+/+) than in the HCT116 (p53-/-) cells. In accordance with enhancement of p53 phosphorylation (Ser-15) and p53 levels, p21 and Bax levels were elevated in the HCT116 (p53+/+) cells treated with 17α-E₂. The HCT116 (p53-/-) cells exhibited barely or undetectable levels of p21 and Bax, regardless of 17α-E₂ treatment. On the other hand, although the level of Bcl-2 was slightly lower in the HCT116 (p53+/+) than in the HCT116 (p53-/-) cells, it remained relatively constant after the 17α-E₂ treatment. Together, these results show that among the components of the 17α-E₂-induced apoptotic-signaling pathway, which proceeds through mitotic spindle defects causing mitotic arrest, subsequent activation of Bak and Bax and the mitochondria-dependent caspase cascade, leading to PARP degradation, 17α-E₂-induced activation of Bak and Bax is the upstream target of proapoptotic action of p53.

Implementation of Specific Activity Models for C-14 in Terrestrial Environment of a Disposal Facility Using GoldSim

Dongki Kim,Joowan Park,Seo-Yeon Cho,Mi-Seon Jeong 한국방사성폐기물학회 2022 한국방사성폐기물학회 학술논문요약집 Vol.20 No.2

In biosphere assessment modeling for the safety assessment of the Wolsong LILW disposal facility, the multi-compartment modeling in which all radionuclides transport is described quantitatively in terms of transfer factors between various environmental compartments has been implemented. In order to reflect the actual transfer mechanisms of 14C in the environment the specific activity (SA) modeling approach can be applied as an alternative to the previous transfer factors (TF) approach. The assumption of full SA equilibrium throughout the terrestrial environment is completely satisfactory for 14C release to the atmosphere if the 12C is emitted as 14CO2. This is the only form that is readily taken up by plants, so that active carbon is incorporated into the plant via photosynthesis at the same rate as stable carbon. Accordingly, the 14C concentration in Bq/g stable carbon is the same in the plant as it is in the air. And animals take up carbon almost entirely through ingestion and the SA ratio in the plant is maintained in the animal. In this study, a specific activity model for 14C was implemented in a GoldSim biosphere assessment model. From the literature survey for existing specific activity models developed, the IAEA model was selected. The farming scenario utilizing well water was simulated and the resulting ingestion dose conversion factors (DCFs) from the IAEA SA model were compared with those of the TF approach. The parameter value for the concentration of stable carbon in the air (gC/m3) is used as 0.20 gC/m3 considering the Suess effect. The dose coefficient for food ingestion used for dose calculations was taken from ICRP-72 as 5.8E-10 Sv/Bq. It was found that the ingestion DCFs of the SA model showed about 3 times lower than those of the TF model in the farming scenario through irrigation of well water, so it is expected that the SA approach could be applied for a more realistic assessment. Though the comparisons were made on the results from the terrestrial ecosystem only in this study, it would be necessary to investigate the applicability of the SA modeling approach for 14C through extensive comparisons and analysis including an aquatic ecosystem, and through parameters survey suitable to the domestic condition.

Juvenile Hormone Action on Vitellogenesis of the Beet Armyworm, Spodoptera exigua

Dongki Kim,Young-In Lee,김용균 한국응용곤충학회 2004 Journal of Asia-Pacific Entomology Vol.7 No.1

Juvenile hormone (JH) is a major insect gonadotropin. However, no endogenous types of JH have been found in beet armyworm, Spodoptera exigua. Here we analyzed the JH effect on vitellogenesis of S. exigua, which was used for determining the type of endogenous JHs in the species. Females were decapitated at different times after adult emergence to remove the source of JH. This treatment prevented vitellogenic development of S. exigua when the decapitation was executed as early as 4h after adult emergence. Both JH analogs, fenoxycarb and pyriproxyfen, induced vitellogenesis of the decapitated females. Similarly, JH I and JH II could induce vitellogenesis of the decapitated females, but not JH III. Follicle cell patency, allowing access of vitellogenin (Vg) in the hemolymph to the growing oocyte, was induced by the application of JH and JH analogs, but not by RH5992, an ecdysteroid agonist. Phenoxyphenyl compounds such as fenoxycarb, KS-175 (1-(4- phenoxyphenoxypropyl) imidazole), and T3 (L-3,5, 3’-triiodothyronine) also significantly induced the follicle cell patency of S. exigua. Among JHs, JH I and JH II could significantly induce follicle cell patency, but not JH III. Both JHs and ecdysteroids could induce Vg biosynthesis. These results suggest that JH I and JH II can be the endogenous types of S. exigua and play roles in the vitellogenesis in both Vg biosynthesis of the fat body and Vg uptake by the growing oocytes.

Disturbance Of Adult Eclosion by Fenoxycarb, a Juvenile Hormone Mimic, in the Beet Armyworm, Spodoptera exigua

Kim, Yonggyun,Kim, Dongki,Lee, Jungeon Korean Society of Applied Entomology 2000 Journal of Asia-Pacific Entomology Vol.3 No.2

Effect of exogeneus juvenile hormones (JHs) on pupal development was assayed in the beet armyworm, Spodoptera exigua. Fenoxycarb, a potent JH mimic, was applied topically to different ages of the pupae, and showed significant inhibition of normal adult eclosion even at 0.1$\mu\textrm{g}$ dose when it was applied at the early pupal stage (day 0). As the pupal development underwent, the susceptibility of the pupae fenoxycarb decreased. RH5992, a potent ecdysteroid mimic, did not, however, any similar inhibiotry effect on the pupae. Natural JH types (JH I, JH II, and JH III) were applied on day 0 pupae to compare their inhibitory effects en adult eclosion. Both JH I and JH III significantly inhibited adult eclosion at 1.0$\mu\textrm{g}$ dose, but JH III did not even at 10.0$\mu\textrm{g}$ dose. It was meted that fenoxycarb-treated pupae showed little rectum development. Fenoxycarb did not, however, show any negative effect on the development of compound eye and wing imaginal discs, and on the pupal hemolymph protein pattern. These results suggest that there should be a commitment period requiring an absence of JH fur a normal adult metamorphosis during early pupal development and that the endogenous type of JH in S. exigua is JH I or JH II or both JHs like other lepidopteran species.

Assessment of Diffusional Release in IAEA ISAM Engineered Vault Disposal Facility

Dongki Kim,Wontak Lee,Joowan Park,Soonyoung Kim 한국방사성폐기물학회 2021 한국방사성폐기물학회 학술논문요약집 Vol.2021 No.11

Application of RESRAD-OFFSITE to IAEA Vault Test Case for Radwaste Disposal Safety Assessment

DongKi Kim,JooWan Park,SoonYoung Kim 한국방사성폐기물학회 2021 한국방사성폐기물학회 학술논문요약집 Vol.2021 No.06

A K-Band Low-Power Miniaturized Hyperthermia System

Dongki Kim,Kihyun Kim,Jungmin Oh,Youngrak Park,Youngwoo Kwon 한국전자파학회JEES 2009 Journal of Electromagnetic Engineering and Science Vol.9 No.4

A K-band low-power miniaturized planar-type hyperthermia system was developed to replace massive and expensive equipment. The system consists of a VCO with a buffer amplifier, a high-power amplifier module, a 20-㏈-coupled line coupler, a chip circulator and two power detectors for signal generation, amplification and power monitoring. All these components have been implemented in planar form on two module blocks. The total size of the hyperthermia system was less than 10×6.5×3 ㎤. In order to verify the system performance, ablations were carried out on nude mice xenografted with human breast cancer. Ablation results show performance comparable to the massive components-based system. This work shows the feasibility of a low-cost miniaturized hyperthermia system for practical clinical applications.