• BMB Reports
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• 제33권4호
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• pp.321-325
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• 2000

Quinone reductase was purified to homogeneity from bovine liver by using ammonium sulfate fractionation, ionexchange chromatography, and gel filtration chromatography. The enzyme utilized either NADH or NADPH as the electron donor. The enzyme catalyzed the reduction of several quinones and other artificial electron acceptors. Furthermore, the enzyme catalyzed NAD(P)H-dependent reduction of azobenzene. The apparent Km for 1,4-benzoquinone and azobenzene was 1.64 mM and 0.524 mM, respectively. The reduction of azobenzene by quinone reductase was almost entirely inhibited by dicumarol or Cibacron blue 3GA, potent inhibitors of the mammalian quinone reductase. In the presence of 1.0${\mu}M$ Cibacron blue 3GA, azoreductase activity was lowered by 45%, and almost complete inhibition was seen above 2.0 ${\mu}M$ Cibacron blue 3GA.

• Biotechnology and Bioprocess Engineering:BBE
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• 제6권4호
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• pp.264-268
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• 2001

Aggregates of specific cells are often regarded as better from in artificial organs and mammalian cell bioreactors in terms of cell-specific functionality. In this study, the morphology and liver specific functions of freshly harvested primary rat hepatocytes, which were cultivated as spheroids and entrapped in a synthetic thermo-reversible extracellular matrix, were examined and compared to a control (hepatocytes in single cell form). A copolymer of N-isopropylacrylamide(98 mole % in feed) and acrylic acid (poly (NiPAAm-co-AAC)), a thermo- reversible copolymer gel ma- trix, was used to entrap hepatocytes either in spheroids or single cells. During a 7-day culture pe-riod, the spheroids maintained higher viability and produced albumin and urea at a relatively con-stant rate, while, the single cell culture showed a slight increase in cell numbers and a reduction in albumin secretion Hepatocytes cultrured as spheroids present a potentially useful three-dimensional cell culture system for application in bioartificial liver device.

• 한국응용곤충학회지
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• 제34권2호
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• pp.95-99
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• 1995

무당벌레(Harmonia axyridis)의 중장 내에서 먹이 단백질이 소화되는 과정을 연구하기 위하여 진딧물과 생간의 AP를 모델 단백질로 이용하였다. 천역 먹이인 긴꼬리볼록진딧물(Megoura crassicauda)과 인공먹이인 닭의 생간은 각각 고유의 acid phosphatase(AP)를 가지고 있으며, 무당벌레의 중장 내부로 들어온 후에도 활성을 나타내었다. 무당벌레의 장에서 자체적으로 생성하여 중장 내부로 분비하는 AP는 관찰되지 않았다. 무당벌레의 단백질 소화력은 먹이의 종류에 따라 차이를 나타내는 경향을 보였다. 생간의 AP는 무당벌레 중장내에서 12시간이 지나면 거의 활성을 잃어 버리나 긴꼬리볼록 진딧물의 AP는 24시간이 경과하여도 강한 활성을 나타내었다.

• 한국식품과학회지
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• 제40권6호
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• pp.621-625
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• 2008

오징어 간유 미세캡슐화 분말을 HPMC-FCC, zein-DP로 코팅하여 유동층 코팅 특성을 살펴본 결과, 유동층 코팅 효율은 HPMC-FCC, zein-DP 모두 90%의 효율을 나타내었다. 겉보기 밀도는 zein-DP 코팅분말이 0.6 g/mL로 높게 나타나 코팅 분말의 비중이 커져 흐름성이 개선되었음을 확인할 수 있었다. 인공위액과 인공장액에 대한 용해성을 살펴본 결과, HPMC-FCC는 각각 59.9%와 0%를 나타내었고 zein-DP는 각각 0%와 31.0%를 나타내어 코팅재료에 따라 용해성을 조절할 수 있었다. 저장 안정성은 zein-DP나 HPMC-FCC로 코팅한 분말이 미세캡슐화 분말보다 높은 PUFA/SFA 잔존율을 보여, 유동층 코팅 기술이 유지식품의 안정성을 확보할 수 있는 새로운 기술이 될 수 있음을 확인할 수 있었다.

• BMB Reports
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• 제28권2호
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• pp.184-190
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• 1995

Functional study of the gap junction channel has been hindered by its inaccessibility in situ. Identification of forms of this channel in artificial membrane has been elusive because of the lack of identifying channel physiology. Connexin32 forms gap junction channels between neighboring cells in rat liver. Connexin32 was affinity-purified using a monoclonal antibody and reconstituted into artificial phospholipid vesicles. The reconstituted connexin32 formed channels through the vesicle membrane that were permeable to sucrose (Stokes radius: $5{\AA}$). The permeability to sucrose was reversibly reduced by acidic pH. In addition, the pH effect on the permeability to sucrose fit well with by the Hill's equation (where, n=2.7 and pK=6.7).

• 시스템엔지니어링학술지
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• 제15권2호
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• pp.72-78
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• 2019

Pathology is the motor that drives healthcare to understand diseases. The way pathologists diagnose diseases, which involves manual observation of images under a microscope has been used for the last 150 years, it's time to change. This paper is specifically based on tumor detection using deep learning techniques. Pathologist examine the specimen slides from the specific portion of body (e-g liver, breast, prostate region) and then examine it under the microscope to identify the effected cells among all the normal cells. This process is time consuming and not sufficiently accurate. So, there is a need of a system that can detect tumor automatically in less time. Solution to this problem is computational pathology: an approach to examine tissue data obtained through whole slide imaging using modern image analysis algorithms and to analyze clinically relevant information from these data. Artificial Intelligence models like machine learning and deep learning are used at the molecular levels to generate diagnostic inferences and predictions; and presents this clinically actionable knowledge to pathologist through dynamic and integrated reports. Which enables physicians, laboratory personnel, and other health care system to make the best possible medical decisions. I will discuss the techniques for the automated tumor detection system within the new discipline of computational pathology, which will be useful for the future practice of pathology and, more broadly, medical practice in general.

• 한국고분자학회지:고분자과학과기술
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• 제10권6호
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• pp.763-772
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• 1999

• Korean Journal of Radiology
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• 제24권4호
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• pp.294-304
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• 2023

Objective: We aimed to investigate whether image standardization using deep learning-based computed tomography (CT) image conversion would improve the performance of deep learning-based automated hepatic segmentation across various reconstruction methods. Materials and Methods: We collected contrast-enhanced dual-energy CT of the abdomen that was obtained using various reconstruction methods, including filtered back projection, iterative reconstruction, optimum contrast, and monoenergetic images with 40, 60, and 80 keV. A deep learning based image conversion algorithm was developed to standardize the CT images using 142 CT examinations (128 for training and 14 for tuning). A separate set of 43 CT examinations from 42 patients (mean age, 10.1 years) was used as the test data. A commercial software program (MEDIP PRO v2.0.0.0, MEDICALIP Co. Ltd.) based on 2D U-NET was used to create liver segmentation masks with liver volume. The original 80 keV images were used as the ground truth. We used the paired t-test to compare the segmentation performance in the Dice similarity coefficient (DSC) and difference ratio of the liver volume relative to the ground truth volume before and after image standardization. The concordance correlation coefficient (CCC) was used to assess the agreement between the segmented liver volume and ground-truth volume. Results: The original CT images showed variable and poor segmentation performances. The standardized images achieved significantly higher DSCs for liver segmentation than the original images (DSC [original, 5.40%-91.27%] vs. [standardized, 93.16%-96.74%], all P < 0.001). The difference ratio of liver volume also decreased significantly after image conversion (original, 9.84%-91.37% vs. standardized, 1.99%-4.41%). In all protocols, CCCs improved after image conversion (original, -0.006-0.964 vs. standardized, 0.990-0.998). Conclusion: Deep learning-based CT image standardization can improve the performance of automated hepatic segmentation using CT images reconstructed using various methods. Deep learning-based CT image conversion may have the potential to improve the generalizability of the segmentation network.

• Journal of Oral Medicine and Pain
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• 제24권2호
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• pp.137-143
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• 1999

Aucubin, the natural product, which is isolated from Aucuba japonica, has a variety of pharmacological effects such as liver-protective function, inhibition of liver RNA and protein biosynthesis, hypotensive activity and antimicrobial effect, etc. This study was performed to investigate the effects of iridoid compounds on wound healing. The author prepared 0.1% aucubin solution and 0.1% aucubin ointment as an active form, aucubigenin to which aucubin was converted by ${\beta}$-glucosidase. Artificial surgical wound was made on either 1cm lateral side of the dorsal midline along the axis of spine of Sprague-Dawley rats under sterile technique. Application of 0.1% aucubin solution or 0.1% aucubin ointment to surgical wound was done daily. Light microscopic examination was performed on the postsurgical 3 days, 5 days, and 9 days. The 0.1% aucubin solution group epithelialized earlier than the control group and the fibrosis of granulation tissue of both aucubin groups were more prominent than the control group. Collectively, this study suggests the possibility of aucubin as a topical agent. Further research should be performed on the mechanism of aucubin on wound healing and proper formulation for effective topical agents.

• 한국어류학회지
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• 제35권4호
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• pp.236-243
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• 2023

본 연구는 조피볼락 치어를 대상으로 인위적인 수온 상승에 따른 생존율, 혈중 cortisol, glucose, GOT, GPT 농도 및 아가미와 간의 조직학적 변화를 조사하였다. 실험 수온은 26℃, 28℃, 30℃ 및 31℃로 설정하였고, 수온은 23℃ (initial)~28℃까지는 1일에 1℃씩, 28~31℃까지는 3일에 1℃씩 조절하였다. 실험은 각 실험 수온에서 7일 동안 수행하였고, 실험기간 동안 먹이는 공급하지 않았다. 그 결과, 26℃와 28℃는 폐사가 발생하지 않았으나, 30℃는 노출 4일째부터 폐사가 발생하여 실험종료 시 1.5%의 생존율을 보였고, 31℃는 노출 1일째부터 폐사가 발생하여 노출 2일째 전량 폐사하였다. 혈중 스트레스 관련 지표를 분석한 결과, 혈중 cortisol과 glucose 농도는 수온이 높을수록 증가하였고, 31℃에서 initial보다 유의하게 감소하였다(p<0.05). 혈중 GPT 농도는 모든 실험구 사이에 유의한 차이를 보이지 않았으나(p<0.05), 혈중 GOT 농도는 31℃에서 유의하게 증가하였다(p<0.05). 간과 아가미의 조직학적 관찰 결과, 간과 아가미는 모두 23℃ (initial) 및 26℃에서 정상적인 조직상을 보였으나, 28℃는 간세포의 비대화 및 아가미 새판 상피세포의 증식과 새판 상피의 탈락, 30℃는 간세포들이 응축 및 아가미 새판의 융합, 31℃는 간 조직 내 충혈 및 일부 간세포의 괴사 및 아가미 새엽과 새판의 괴사가 관찰되었다.