• The Korean Journal of Physiology and Pharmacology
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• 제7권6호
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• pp.317-323
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• 2003

Interneuron diversity is one of the key factors to hinder understanding the mechanism of cortical neural network functions even with their important roles. We characterized inhibitory interneurons in layer II/III of the rat primary visual cortex, using patch-clamp recording and confocal reconstruction, and classified inhibitory interneurons into fast spiking (FS), late spiking (LS), burst spiking (BS), and regular spiking non-pyramidal (RSNP) neurons according to their electrophysiological characteristics. Global parameters to identify inhibitory interneurons were resting membrane potential (＞-70 mV) and action potential (AP) width (＜0.9 msec at half amplitude). FS could be differentiated from LS, based on smaller amplitude of the AP (＜∼50 mV) and shorter peak-to-trough time (P-T time) of the afterhyperpolarization (＜4 msec). In addition to the shorter AP width, RSNP had the higher input resistance (＞200 $M{Omega}$) and the shorter P-T time (＜20 msec) than those of regular spiking pyramidal neurons. Confocal reconstruction of recorded cells revealed characteristic morphology of each subtype of inhibitory interneurons. Thus, our results provide at least four subtypes of inhibitory interneurons in layer II/III of the rat primary visual cortex and a classification scheme of inhibitory interneurons.

• Animal cells and systems
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• 제8권4호
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• pp.295-300
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• 2004

In the breeding colony of black-tailed gull, as nests of conspecific neighbors are very closely located, chicks are permanently exposed by sound and visual stimuli produced by adult conspecifics approaching their nests. The chicks, therefore, may need to learn ways to appropriately respond to their parents approach. In this study we experimentally manipulated sensory stimulation that is potentially provided by the parents to the offspring. Chicks incubated in the laboratory were exposed to a mew call of the conspecific adult. Then they were tested in three situations differing in sensory stimulation: 1) visual stimulation only, 2) auditory stimulation only, and 3) Simultaneous visual and auditory stimulations. We observed occurrence of different response of the chicks, which were categorized into three behaviors (begging call response, chirirah call and pecking behavior). We also investigated intensity of the chicks call in response to the different stimulations and the degree of response with age. The chicks exposed to only auditory stimulation made significantly more chirirah calls. The intensities (dB) of the mew call and chicks chirirah call were directly correlated. On the other hand, when chicks just saw the stuffed adult gull, they responded significantly more with a begging call and pecking behavior. In the situation of costimulation, the chicks responded with a begging call and pecking, but less frequently than visual stimulation only. The results suggest that young black-tailed gulls use call repertories to properly respond to parents behavior. Such results suggest an evolutionary process for uncreasing their survival rate in a group breeding site.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 V
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• pp.2911-2914
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• 2003

Conventionally, biological manipulations have been performed manually with long training and pretty low success rates. To overcome this problem, a novel biological manipulation system has been developed to manipulate biological cells without any interference of a human operator, In this paper, we demonstrate a development of tole-autonomous Cell Manipulation System (CMS) using an image processing at a remote site. The CMS consists of two manipulators, a plane stage, and an optical microscope. We developed deformable template-model-matching algorithm for micro objects and pattern matching algorithm of end effect for these manipulators in order to control manipulators and the stage. Through manipulation of biological cells using these algorithms, the performance of the CMS is verified experimentally.

• 산업공학
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• 제16권2호
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• pp.149-155
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• 2003

The focus of this study is to investigate how personal display systems - a VDU (Visual Display Unit) and an HMD (Head Mounted Display) physiologically affect the body in virtual environments, and to evaluate differential effects of using the VDU and the HMD on physiological responses to mental stressful tasks (virtual reality flight simulation). As physiological variables, autonomic measures (heart rate, blood pressure), immune cells (leukocyte, neutrophil, lymphocyte), and hormones (catecholamine) were measured before and after experiments. Physiological data were measured in order to compare a level of mental stress on the VDU and the HMD. Increments in blood pressure (systolic (p<0.05), diastolic (p<0.1)), norepinephrin (catecholamine) (p<0.005), and neutrophils (p<0.2) of the group using the HMD showed a significant difference with the group using the VDU. Although, the heart rate was not statistically significant between two environments, differences of them quietly increased on the HMD more than on the VDU.

• Advances in robotics research
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• 제1권2호
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• pp.127-140
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• 2014

This work presents an IR-based system for parking assistance and obstacle detection in the automotive field that employs the Microsoft Kinect camera for fast 3D point cloud reconstruction. In contrast to previous research that attempts to explicitly identify obstacles, the proposed system aims to detect "reachable regions" of the environment, i.e., those regions where the vehicle can drive to from its current position. A user-friendly 2D traversability grid of cells is generated and used as a visual aid for parking assistance. Given a raw 3D point cloud, first each point is mapped into individual cells, then, the elevation information is used within a graph-based algorithm to label a given cell as traversable or non-traversable. Following this rationale, positive and negative obstacles, as well as unknown regions can be implicitly detected. Additionally, no flat-world assumption is required. Experimental results, obtained from the system in typical parking scenarios, are presented showing its effectiveness for scene interpretation and detection of several types of obstacle.

• 생명과학회지
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• 제9권3호
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• pp.308-313
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• 1999

Ocellar morphological abnormality was studied in Drosophila rdgA mutant. In the mutant, ocellar photoreceptor cells were generally affected by the defection of rdgA molecules. Among organelles of photoreceptor cell, rhabdomeres were remarkably degenerated. The rdgA molecule, diacylglycerol kinase, was localized around SRC just below the rhabdomeric region. As a secondary phenomenon of photoreceptor degeneration, rER, multivesicular body and multilamella body were appeared in cytoplasm and these were known as to clean the cellular debris. These morphological abnormality was generally observed in degenerating cells. In Drosophila mutant, the degeneration of ocellar photoreceptor cell was facilitated to time. More intense morphological defection was observed in rdgA^{ks60} rather than in yw;rdgApc47.

• Molecules and Cells
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• 제37권8호
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• pp.613-619
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• 2014

The optic nerve often suffers regenerative failure after injury, leading to serious visual impairment such as glaucoma. The main inhibitory factors, including Nogo-A, oligodendrocyte myelin glycoprotein, and myelin-associated glycoprotein, exert their inhibitory effects on axonal growth through the same receptor, the Nogo-66 receptor (NgR). Oncomodulin (OM), a calcium-binding protein with a molecular weight of an ~12 kDa, which is secreted from activated macrophages, has been demonstrated to have high and specific affinity for retinal ganglion cells (RGC) and promote greater axonal regeneration than other known polypeptide growth factors. Protamine has been reported to effectively deliver small interference RNA (siRNA) into cells. Accordingly, a fusion protein of OM and truncated protamine (tp) may be used as a vehicle for the delivery of NgR siRNA into RGC for gene therapy. To test this hypothesis, we constructed OM and tp fusion protein (OM/tp) expression vectors. Using the indirect immunofluorescence labeling method, OM/tp fusion proteins were found to have a high affinity for RGC. The gel shift assay showed that the OM/tp fusion proteins retained the capacity to bind to DNA. Using OM/tp fusion proteins as a delivery tool, the siRNA of NgR was effectively transfected into cells and significantly down-regulated NgR expression levels. More importantly, OM/tp-NgR siRNA dramatically promoted axonal growth of RGC compared with the application of OM/tp recombinant protein or NgR siRNA alone in vitro. In addition, OM/tp-NgR siRNA highly elevated intracellular cyclic adenosine monophosphate (cAMP) levels and inhibited activation of the Ras homolog gene family, member A (RhoA). Taken together, our data demonstrated that the recombinant OM/tp fusion proteins retained the functions of both OM and tp, and that OM/tp-NgR siRNA might potentially be used for the treatment of optic nerve injury.

• 한국융합학회논문지
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• 제11권3호
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• pp.163-170
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• 2020

본 연구는 최근 급속도로 성장하고 있는 태양전지를 활용한 국내외 도시 디자인의 현황과 동향을 파악하고, 사례 분석을 토대로 향후 진행할 연구과제인 CIGS 박막 태양전지를 활용한 도시 디자인 제안의 긍정적인 측면과 시사점을 파악하고자 하였다. 연구 방법은 문헌연구를 통하여 이론적 고찰을 진행하였고, 이후에 국내외 태양전지를 활용한 도시 디자인의 현황과 동향을 파악하여 사례를 조사·분석하였다. 그 결과 태양전지를 활용한 도시 디자인은 꾸준히 증가하고 있음을 확인하였으며, 주변 환경과의 조화, 실내외 동반 미관창출, 색상의 활용 등의 시각적인 변화를 통하여 심미적 도시 미관창출의 긍정적 효과가 있는 것을 알 수 있었다. 이러한 시사점을 바탕으로 CIGS 박막 태양전지를 도시 디자인에 활용하였을 때 올 수 있는 기대효과를 제시하고, 향후 진행할 CIGS 박막 태양전지를 활용한 도시 디자인 제안에 대한 방향성과 의의를 확인하고자 한다.

• Journal of Ginseng Research
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• 제47권1호
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• pp.65-73
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• 2023

Background: Age-related macular degeneration (AMD) is a significant visual disease that induces impaired vision and irreversible blindness in the elderly. However, the effects of ginseng berry extract (GBE) on the retina have not been studied. Therefore, this study aimed to investigate the protective effects of GBE on blue light (BL)-induced retinal damage and elucidate its underlying mechanisms in human retinal pigment epithelial cells (ARPE-19 cells) and Balb/c retina. Methods: To investigate the effects and underlying mechanisms of GBE on retinal damage in vitro, we performed cell viability assay, pre-and post-treatment of sample, reactive oxygen species (ROS) assay, quantitative real-time PCR (qRT-PCR), and western immunoblotting using A2E-laden ARPE-19 cells with BL exposure. In addition, Balb/c mice were irradiated with BL to induce retinal degeneration and orally administrated with GBE (50, 100, 200 mg/kg). Using the harvested retina, we performed histological analysis (thickness of retinal layers), qRT-PCR, and western immunoblotting to elucidate the effects and mechanisms of GBE against retinal damage in vivo. Results: GBE significantly inhibited BL-induced cell damage in ARPE-19 cells by activating the SIRT1/PGC-1α pathway, regulating NF-kB translocation, caspase 3 activation, PARP cleavage, expressions of apoptosis-related factors (BAX/BCL-2, LC3-II, and p62), and ROS production. Furthermore, GBE prevented BL-induced retinal degeneration by restoring the thickness of retinal layers and suppressed inflammation and apoptosis via regulation of NF-kB and SIRT1/PGC-1α pathway, cleavage of caspase 3 and PARP, and expressions of apoptosis-related factors in vivo. Conclusions: GBE could be a potential agent to prevent dry AMD and progression to wet AMD.

• Journal of Microbiology and Biotechnology
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• 제27권7호
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• pp.1359-1366
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• 2017

(E)-2-Methoxy-4-(3-(4-methoxyphenyl)prop-1-en-1-yl)phenol (MMPP), derived from butenal, is a recently synthesized Maillard reaction product. Owing to its novelty, little is known about the function of MMPP. In this study, we elucidated the effects of MMPP on apoptosis in cervical cancer by using the HeLa cervical cancer cell line, which is widely used in cancer research. We observed that MMPP was cytotoxic to HeLa cells and induced activation of caspase-3, -8, and -9, without affecting the expression of the viral oncogenes E6 and E7. In particular, the expression of the death receptors DR5 and FAS was significantly increased by MMPP treatment. There were no significant alterations of mitochondrial intrinsic factors. Taking all these results together, our findings show that MMPP primarily induces apoptosis in HeLa cervical cancer cells via the extrinsic apoptotic signaling pathway, accompanied by an enhanced expression of death receptors.