Selective Electrochemical Detection of Dopamine Using Reduced Graphene Oxide Sheets-Gold Nanoparticles Modified Electrode

Park, Da-Jeong,Choi, Jin-Ha,Lee, Won-Jin,Um, Soong Ho,Oh, Byung-Keun American Scientific Publishers 2017 Journal of Nanoscience and Nanotechnology Vol.17 No.11

<P>Dopamine (DA) is one of the most significant neurotransmitters, and it has a major role in the central nervous system, such as in cognition, motivation, and memory. Some neural diseases, including Alzheimer's disease (AD) and Parkinson's diseases (PD), are related with a lack of DA. Thus, the detection of DA is necessary for the early diagnosis of such diseases. In this study, we fabricate an electrochemical sensor by modifying an electrode with reduced graphene oxide sheet (rGS)-gold nanoparticle (GNP) complexes to determine DA and ascorbic acid (AA) in a mixture within a range of 0.1-100 mu M. The rGS was used to improve the selectivity of the sensor by having pi-pi interaction with DA, and the GNPs improved the sensitivity due to their great conductivity and large surface area. As a result, when the GNPs were immobilized on the rGS surface, the sensor exhibited greatly improved electrocatalytic activity compared with other cases, such as the individual application of rGS or GNPs. The performance of the sensor with the modified electrode was confirmed by scanning electron microscopy (SEM), cyclic voltammetry (CV), and differential pulse voltammetry (DPV) measurements. The results showed that it had linearity in the range of 0.1-100 mu M of DA and the limit of detection was 0.098 mu M in the presence of AA 400 mu M. Therefore, it could be applied to medical biosensors to diagnose neural diseases.</P>

Effects of Dyglomera® on leptin expression, pro-inflammatory cytokines, and adipocyte browning in 3T3-L1 cells

Da-Eun Min,Sung-Kwon Lee,Hae Jin Lee,Bong-Keun Choi,Dong-Ryung Lee 한국응용생명화학회 2023 Journal of Applied Biological Chemistry (J. Appl. Vol.66 No.-

Dyglomera® is an aqueous ethanol extract derived from the fruit and pods of Dichrostachys glomerata. A previous study has revealed that Dyglomera regulates adipogenesis and lipolysis by modulating AMP-activated protein kinase (AMPK) phosphorylation and increased expression levels of lipolysisrelated proteins in white adipose tissue of high fat diet-induced mice and 3T3-L1 adipocyte cells. To further investigate mechanisms of Dyglomera, additional studies were performed using 3T3-L1 cells. Results revealed that Dyglomera downregulated adipogenesis by inhibiting the protein kinase B/mammalian target of rapamycin signaling pathway and reconfirmed that it downregulated gene expression levels of proliferator-activated receptor (PPAR)-γ, CCAAT enhancer binding protein α, sterol-regulation elementbinding protein-1c. Dyglomera also reduced adipokines such as tumor necrosis factor alpha, interleukin-1β, and interleukin 6 by regulating leptin expression. Moreover, Dyglomera promoted beige-and-brown adipocyte-related phenotypes and regulated metabolism by increasing mitochondrial number and expression levels of genes such as T-box protein 1, transmembrane protein 26, PR domain 16, and cluster of differentiation 40 as well as thermogenic factors such as uncoupling protein 1, proliferatoractivated receptor-gamma co-activator-1α, Sirtuin 1, and PPARα through AMPK activation. Thus, Dyglomera not only can inhibit adipogenesis, but also can promote lipolysis and thermogenesis and regulate metabolism by affecting adipokine secretion from 3T3-L1 adipocytes.

Analysis of Flood Causes and Damages of Paddy Field in the Osong Region

Da Ye Kim,Seung Jin Maeng,Hyo Sang Lee,Ho Jin Lee,Hyung Joon Chang,Seung Wook Lee,Hyung Keun Park 위기관리 이론과 실천 2021 Crisisonomy Vol.17 No.9

2017년 7월 16일에 발생한 집중호우로 인하여 오송 제2생명과학단지 남쪽 정중3리, 봉산3리 및 서평2 리에 농경지 및 주택의 침수 피해가 발생하였다. 청주 지역에 발생한 홍수사상을 분석하고, 오송 지역에 미치는 영향을 확인하고자 관측 수문자료를 바탕으로 강우빈도 해석을 실시하였으며, 이를 통해 홍수사상의 재현빈도를 산정하고, 홍수사상이 확률강우량 산정에 미치는 영향을 확인하였다. 또한 홍수피해 지역의 분석을 위해 GATE2012 침수모의 프로그램을 이용하였으며, 연구 대상지 내 발생유량의 유입을 반영하지 않은 경우와 반영한 경우로 구분하여 모의하였다. 발생유량의 유입을 반영하지 않은 경우는 양배수장 미가동시과 정상 가동시로 구분하였고, 반영한 경우는 발생유량을 변화시켜 총 9가지 Case로 구분하여 침수분석을 실시하였다. 본 연구를 통해 연구 대상지의 유출량을 산정하여 침수형태를 분석하고 양배수장의 침수방어 역할을 판단할 수 있었으며, 추후 홍수시 농경 지 침수피해 분석의 신뢰성을 향상시키고 이를 통한 침수 방지 계획을 수립하는 데 기여하고자 한다. A severe rain storm that occurred on July 16, 2017, caused flooding of paddy fields and rural houses south of Osong Biovalley. To analyze the flood event that occurred in the Cheongju area and to verify its effects on the Osong area, rainfall frequency analysis was evaluated based on the observed hydrological data. The recurrence frequency of flood events was estimated through rainfall frequency analysis, and the effect of flood events on the estimation of probable rainfall was confirmed. The GATE2012 flood simulation program was used to analyze the flood-damaged area. The program simulation was performed by dividing it into the case where the inflow of the generated discharge within the study area was not reflected and the case where it was reflected. In the case of not reflecting the inflow of the generated discharge, it was divided into the non-operational and normal operation of the pumping and drainage station, and in the case of consideration, the generated discharge was changed and the inundation analysis was performed by classifying it into nine cases. Through this study, it is to improve the reliability of the analysis of flood damage in paddy fields during floods and to contribute to the establishment of a flood prevention plan.

The detecion of African swine fever virus via hair plucking: An alternative non-invasive approach

Chae-Rin Park(Chae-Rin Park),Tae-Young Suh(Tae-Young Suh),Da-Hye Yi(Da-Hye Yi),Soo-Kyoung Lee(Soo-Kyoung Lee),Seong-Keun Hong(Seong-Keun Hong),Ki-Hyun Cho(Ki-Hyun Cho),Jee-Yong Park(Jee-Yong Park),Yon 한국예방수의학회 2022 한국예방수의학회 학술대회자료집 Vol.2022 No.-

아스파라거스 줄기 및 뿌리 추출물의 기능성 검증

한준희(Joon-Hee Han),홍민(Min Hong),이재학(Jaehak Lee),최다혜(Da-Hye Choi),이선엽(Sun-Yeop Lee),권태형(Tae-Hyung Kwon),이재희(Jae-Hee Lee),이용진(Yong-Jin Lee),유근형(Keun-Hyung Yu) 한국식품과학회 2021 한국식품과학회지 Vol.53 No.1

본 연구에서는 아스파라거스 부산물인 줄기와 뿌리 추출물의 루틴 및 총폴리페놀 함량, DPPH 및 ABTS radical 소거능, xanthine oxidase 및 MMP-9 저해활성, 간세포 보호효과를 분석하였다. 루틴과 총폴리페놀 함량은 아스파라거스 줄기 열수 추출물 31.74 mg/g과 20.14 mg GAE/g으로 가장 많았으며, ABTS radical 및 DPPH radical 소거능은 페놀성 화합물의 함량이 상대적으로 높은 줄기 열수 추출물에서 IC<SUB>50</SUB> 값이 각각 541.1±21.0, 649.5±6.6μg/mL이였으며, 아스파라거스 추출물에 존재하는 페놀성 화합물과 radical 소거능과의 연관성을 시사하였다. Xanthine oxidase 저해활성은 아스파라거스 뿌리 열수추출물이 200 μg/mL 농도에서 43.68%의 저해활성을 보였다. HepG2 간세포는 아스파라거스 모든 추출물에서 세포독성이 없는 것으로 나타났으나, RAW 264.7대식세포의 경우 아스파라거스 줄기 열수 및 20% 에탄올 추출물 200 μg/mL 농도에서 각각 90.18, 84.14%로 생존률이 유의하게 감소하는 것으로 나타났다. MMP-9 발현량은 아스파라거스 추출물 처리구에서 전반적으로 감소하였고, 특히 줄기 추출물 처리구에서 MSU 처리구와 비교하여 유의하게 감소하는 경향을 보였다. HepG2 간세포에 3% 에탄올을 처리하여 간독성을 유발하여 GGT, AST 및 LDH 활성을 측정한 결과 아스파라거스 줄기 20%에탄올 추출물이 가장 우수한 것으로 나타났다. 이 결과를 토대로 아스파라거스 줄기 및 뿌리는 총 폴리페놀과 루틴이 다량 함유되어 있어 생리활성 소재로써 개발 가치가 높을 것으로 판단되며, 추가적인 in vivo 생리활성평가를 통해 활용방안 모색이 필요할 것으로 판단된다. The biological activities of non-edible extracts of asparagus stems and roots were investigated using hot water and ethanol. The highest contents of rutin and total polyphenol were 31.74 mg/g and 20.14 mg GAE/g, respectively, in the stem hot water extract. ABTS and DPPH radical scavenging activities were 541.1±21.0 and 649.5±6.6 μg/mL, respectively, in stem hot water extract. All extracts were non-cytotoxic in HepG2 cells, but 200 μg/mL stem extracts tended to decrease the viability of RAW 264.7 cells. The highest xanthine oxidase inhibitory activity was 43.68% in the root hot water extract at 200 μg/mL. The expression level of MMP-9 was significantly decreased in the asparagus extracts. The highest GGT, AST, and LDH activities showed a concentration-dependent decrease in the stem ethanol extract. In conclusion, the presence of bioactive substances in the non-edible extracts of asparagus was confirmed for the development of extracts with antioxidant, hepatoprotective and anti-gout activities.

Phosphorylated AMP-activated protein kinase expression associated with prognosis for patients with gastric cancer treated with cisplatin-based adjuvant chemotherapy.

Kang, Byung Woog,Jeong, Ji Yun,Chae, Yee Soo,Lee, Soo Jung,Lee, Yoo Jin,Choi, Jun Young,Lee, In-Kyu,Jeon, Seong Woo,Bae, Han Ik,Lee, Da Keun,Kwon, Oh-Kyoung,Chung, Ho Young,Yu, Wansik,Kim, Jong Gwang Springer 2012 Cancer chemotherapy and pharmacology Vol.70 No.5

<P>Purpose The present study analyzed the expression of phosphorylated AMP-activated protein kinase (pAMPK), Fyn kinase, and pyruvate dehydrogenase kinase-1 (PDK-1) and their impact on the survival of patients with resected gastric cancer who received cisplatin-based adjuvant chemotherapy. Patients and methods Korean patients with stage II-IV (M0) gastric adenocarcinoma who underwent a gastrectomy with D2 lymph node resection and received a combination regimen of cisplatin and S-1 were enrolled. Immunohistochemistry was carried out to determine the expression of pAMPK, Fyn kinase, and PDK-1 in operative specimens of gastric cancer. The expression was divided into two groups according to the intensity score (negative: 0 or 1+ and positive: 2+ or 3+). Results From January 2006 to July 2010, 73 tumor samples obtained from 74 patients were analyzed. Forty patients were included in the pAMPK-positive group, while 33 patients were included in the pAMPK-negative group. Meanwhile, positive Fyn kinase expression was observed in only 10 patients (13.7 %), and there was no or very weak PDK-1 staining. The clinicopathologic characteristics were similar between the two groups according to the expression of pAMPK. With a median follow-up duration of 26.5 months (2.6-73.2), the estimated 3-year relapse-free survival (RFS) and overall survival rates were 55.0 and 78.4 %, respectively. In a multivariate analysis adjusted for age, sex, Lauren classification, and stage, the pAMPK-negative group was significantly associated with improved RFS (Hazard ratio = 0.459, 95 % CI 0.109-0.711, P = 0.043). Conclusion A low expression of pAMPK was found to be correlated with better RFS in patients with resected gastric cancer treated with adjuvant cisplatin-based chemotherapy.</P>

A Study on the Recognition of Face Based on CNN Algorithms

Da-Yeon Son(손다연),Kwang-Keun Lee(이광근) 한국BIM학회 2017 KIBIM Magazine Vol.5 No.2

Recently, technologies are being developed to recognize and authenticate users using bioinformatics to solve information security issues. Biometric information includes face, fingerprint, iris, voice, and vein. Among them, face recognition technology occupies a large part. Face recognition technology is applied in various fields. For example, it can be used for identity verification, such as a personal identification card, passport, credit card, security system, and personnel data. In addition, it can be used for security, including crime suspect search, unsafe zone monitoring, vehicle tracking crime.In this thesis, we conducted a study to recognize faces by detecting the areas of the face through a computer webcam. The purpose of this study was to contribute to the improvement in the accuracy of Recognition of Face Based on CNN Algorithms. For this purpose, We used data files provided by github to build a face recognition model. We also created data using CNN algorithms, which are widely used for image recognition. Various photos were learned by CNN algorithm. The study found that the accuracy of face recognition based on CNN algorithms was 77%. Based on the results of the study, We carried out recognition of the face according to the distance. Research findings may be useful if face recognition is required in a variety of situations. Research based on this study is also expected to improve the accuracy of face recognition.

Nanoscale Protein Chip to Detect Beta-Amyloid(1-42) using Scanning Tunneling Microscopy

Da-Yeon Kang,Jin-Ho Lee,Cheol-Heon Yea,Byung-Keun Oh,Jeong-Woo Choi 한국생물공학회 2008 한국생물공학회 학술대회 Vol.2008 No.4

Optically Pure L(+)-lactic A cid Production by Genetically Modified Lactobacillus sp.

Da Young KIM,Ngoc Tu PHAM,Jin Suk CHUNG,Ik-Keun YOO,Seung Hwan LEE 한국생물공학회 2011 한국생물공학회 학술대회 Vol.2011 No.4

Toxic Effects of Heavy Metals on the Growth and Phosphorus Removal Efficiency of Phosphorus Accumulating Microorganisms (PAOs)

Da Hee Sin,Deok Hyeon Kim,Jong In Kim,Moon-Soon Lee,Keun-Yook Chung 한국토양비료학회 2013 한국토양비료학회지 Vol.46 No.6

Phosphorus accumulating microorganisms (PAOs) are influenced by various environmental factors and heavy metals. This study was performed to evaluate the effects of the selected heavy metals on the growth and phosphorus removal capacity of Bacillus sp. 3434 BRRJ, Pseudomonas aerunogisa, and Bacillus Subtilis, well known as PAOs. The heavy metals used in this study included Cu, Cd, As, and Zn. The IC50 (median inhibition concentration) values of Bacillus sp. 3434 BRRJ for the Cu, Cd, As, and Zn were 8.07 mg L<SUP>-1</SUP>, 0.18 mg L<SUP>-1</SUP>, 73.62 mg L<SUP>-1</SUP> and 0.25 mg L<SUP>-1</SUP>, respectively. The IC50 values of Pseudomonas aerunogisa for the Cu, Cd, As, and Zn were 4.45 mg L<SUP>-1</SUP>, 0.16 mg L<SUP>-1</SUP>, 18.51 mg L<SUP>-1 </SUP>and 2.34 mg L<SUP>-1</SUP>, respectively. The IC50 values of Bacillus Subtilis for the Cu, Cd, As, and Zn were 3.81 mg L<SUP>-1</SUP>, 0.18 mg L<SUP>-1</SUP>, 11.31 mg L<SUP>-1</SUP> and 0.47 mg L<SUP>-1</SUP>, respectively. The phosphorus removal efficiencies of the three bacteria, Bacillus sp. 3434 BRRJ, Pseudomonas aerunogisa, and Bacillus subtilis were 93.12%, 71.81%, and 65.31%, respectively. Based on the results of the three PAOs obtained from the study, it appears that Bacillus sp. 3434BRRJ may have the best results in terms of their growth rate and P removal efficiencies.