• BMB Reports
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• v.56 no.1
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• pp.10-14
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• 2023

Organoids derived from stem cells or organ-specific progenitors are self-organizable, self-renewable, and multicellular three-dimensional (3D) structures that can mimic the function and structure of the derived tissue. Due to such characteristics, organoids are attracting attention as an excellent ex vivo model for drug screening at the stage of drug development. In addition, since the applicability of organoids as therapeutics for tissue regeneration has been embossed, the development of various organoids-based regenerative medicine has been rapidly progressing, reaching the clinical trial stage. In this review, we give a general overview of organoids and describe current status and prospects of organoid-based regenerative medicine, focusing on organoid-based regenerative therapeutics currently under development including clinical trials.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 2003.06a
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• pp.129-131
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• 2003

Recombinant bioluminescent bacteria and cultured human cells were applied for toxicogenomic analysis of environmentally hazardous chemicals. Recombinant bioluminescent biosensing cells were used to detect and classify the toxicity caused by various chemicals. Classification of toxicity was realized based upon the chemicals' mode of action using DNA-, oxidative-, protein, and membrane-damage sensitive strains. As well, a simple double-layered cell culture system using Caco-2 cells and Hep G2 cells, which mimic the metabolic processes occurring in humans, such as adsorption through the small intestine and biotransformationin both the small intestine and the liver, was developed to investigate the toxicity of hazardous materials to humans. For a more in-depth analysis, a DNA microarray was used to study the transcriptional responses of Caco-2 and Hep G2 cells to benzo〔a〕pyrene.

• BMB Reports
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• v.56 no.4
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• pp.225-233
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• 2023

Hepatocellular carcinoma (HCC) is a very common form of cancer worldwide and is often fatal. Although the histopathology of HCC is characterized by metabolic pathophysiology, fibrosis, and cirrhosis, the focus of treatment has been on eliminating HCC. Recently, three-dimensional (3D) multicellular hepatic spheroid (MCHS) models have provided a) new therapeutic strategies for progressive fibrotic liver diseases, such as antifibrotic and anti-inflammatory drugs, b) molecular targets, and c) treatments for metabolic dysregulation. MCHS models provide a potent anti-cancer tool because they can mimic a) tumor complexity and heterogeneity, b) the 3D context of tumor cells, and c) the gradients of physiological parameters that are characteristic of tumors in vivo. However, the information provided by an multicelluar tumor spheroid (MCTS) model must always be considered in the context of tumors in vivo. This mini-review summarizes what is known about tumor HCC heterogeneity and complexity and the advances provided by MCHS models for innovations in drug development to combat liver diseases.

• Proceedings of the Korea Information Processing Society Conference
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• 2009.11a
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• pp.67-68
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• 2009

Increasing use of embedded systems has made many improvements on hardware development for specific purpose. Hardware changes are more expensive and harder to implement rather than software changes. Developers need tools to do design and testing of new hardware. Many simulation tools have been made to mimic the hardware and allow developer to test programs on top of new hardware. Virtual Development Environment for Embedded Software (VDEES) is one of the alternatives available. It provides an open source based platform and an Integrated Development Environment (IDE) that can be used to build and testing newly made component, faster and at low-cost.

• Journal of Korean Neurosurgical Society
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• v.66 no.1
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• pp.105-110
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• 2023

A diagnosis of an intracranial aneurysm depends on the angiographic configuration and should be cautiously differentiated from aneurysm mimics. In cases of duplicate anterior choroidal arteries (AChAs), infundibular widening of the distal minor AChA can be an aneurysm mimic. If the minor AChA with a smaller diameter is obscured angiographically due to poor contrast filling, an associated infundibular widening beside the proximal large AChA can misinterpreted as a typical AChA aneurysm in angiograms. The authors report on two such cases of duplicate AChAs with infundibular widening presenting like a typical AChA aneurysm in angiograms. Surgical exploration revealed a perforating artery emitting from the dome of the saccular lesion, confirming infundibular widening of a duplicate AChA. No reparative procedure was applied to the infundibular widening in a 48-year-old man, while two vascular outpouchings from the infundibular widening were clipped preserving the duplicate AChA in a 55-year-old woman.

• Journal of Korean Neurosurgical Society
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• v.65 no.3
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• pp.397-407
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• 2022

Abusive head trauma (AHT) is the most common and serious form of child abuse and a leading cause of traumatic death in infants and young children. The biomechanics of head injuries include violent shaking, blunt impact, or a combination of both. Neuroimaging plays an important role in recognizing and distinguishing abusive injuries from lesions from accidental trauma or other causes, because clinical presentation and medical history are often nonspecific and ambiguous in this age group. Understanding common imaging features of AHT can increase recognition with high specificity for AHT. In this review, we discuss the biomechanics of AHT, imaging features of AHT, and other conditions that mimic AHT.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.2
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• pp.53.3-53.3
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• 2019

Recent work by Ravanbakhsh et al. (2017), Mathuriya et al. (2018) showed that convolutional neural networks (CNN) can be trained to predict cosmological parameters from the visual shape of the large scale structure, i.e. the filaments, clusters and voids of the cosmic density field. These preliminary works used the dark matter density field at redshift zero. We build upon these works by considering realistic mock galaxy catalogues that mimic true observations. We construct light-cones that span the redshift range appropriate for current and near future cosmological surveys such as LSST, EUCLID, WFIRST etc. In summary, we propose a novel multi-image input CNN to track the evolution in the morphology of large scale structures over cosmic time to constrain cosmology and the expansion history of the Universe.

• Development and Reproduction
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• v.27 no.2
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• pp.57-65
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• 2023

Kidney disease affects a significant portion of the global population, yet effective therapies are lacking despite advancements in identifying genetic causes. This limitation can be attributed to the absence of adequate in vitro models that accurately mimic human kidney disease, hindering targeted therapeutic development. However, the emergence of human induced pluripotent stem cells (PSCs) and the development of organoids using them have opened up a way to model kidney development and disease in humans, as well as validate the effects of new drugs. To fully leverage their capabilities in these fields, it is crucial for kidney organoids to closely resemble the structure and functionality of adult human kidneys. In this review, we aim to discuss the potential of using human PSCs or adult kidney stem cell-derived kidney organoids to model genetic kidney disease and renal cancer.

• Journal of Yeungnam Medical Science
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• v.40 no.2
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• pp.198-201
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• 2023

Invasive sphenoid sinus aspergillosis can mimic Tolosa-Hunt syndrome (THS), leading to frequent misdiagnoses and potentially fatal consequences. We report a case of invasive sphenoid sinus aspergillosis initially misdiagnosed as THS. A 79-year-old man presented with right periorbital pain, ophthalmoplegia, and loss of vision. Initial evaluations including magnetic resonance imaging (MRI), were normal. He was first diagnosed with THS based on clinical features. The disease progressed despite high-dose intravenous steroid treatment, and an enhancing mass-like lesion was found in the right orbital apex, cavernous sinus, and sphenoid sinus on follow-up MRI. Aspergillosis was eventually confirmed by sphenoid sinus biopsy. The patient developed cerebral infarction and finally died despite being treated with amphotericin B. Given that invasive sphenoid sinus aspergillosis may initially resemble THS, high suspicion and rapid histological examination are important for diagnosis.

• Proceedings of the Korea Information Processing Society Conference
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• 2022.11a
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• pp.520-522
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• 2022

의료 인공지능은 특정 진단에서 높은 정확도를 보이지만 모델의 신뢰성 문제로 인해 활발하게 쓰이지 못하고 있다. 이에 따라 인공지능 모델의 진단에 대한 원인 설명의 필요성이 대두되었고 설명가능한 의료 인공지능에 관한 연구가 활발히 진행되고 있다. 하지만 MRI 등 의료 영상 인공지능 분야에서 주로 진행되고 있으며, 이미지 형태가 아닌 전자의무기록 데이터 (Electronic Health Record, EHR) 를 기반으로 한 모델의 설명가능성 연구는 EHR 데이터 자체의 복잡성 때문에 활발하게 진행 되지 않고 있다. 본 논문에서는 전자의무기록 데이터인 MIMIC-III (Medical Information Mart for Intensive Care) 를 전처리 및 그래프로 표현하고, GCT (Graph Convolutional Transformer) 모델을 학습시켰다. 학습 후, 어텐션 흐름 그래프를 시각화해서 모델의 예측에 대한 직관적인 설명을 제공한다.