• 한국독성학회:학술대회논문집
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• 한국독성학회 2003년도 춘계학술대회 논문집
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• pp.29-30
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• 2003

The heavy metal cadmium is a xenobiotic toxicant of environmental and occupational concern and it has been classified as a human carcinogen. Inhalation of cadmiumhas been implicated in the development of emphysema and pulmonary fibrosis, but, the detailed mechanism by which cadmium induces adverse biological effects is not yet known.(omitted)

• 대한전기학회논문지:시스템및제어부문D
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• 제52권5호
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• pp.259-267
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• 2003

In this paper, we propose a nonlinear variable PID controller using a cell-mediated immune response. An immune feedback response is based on the functioning of biological T-cells. An immune feedback response and P-controller of conventional PID controllers resemble each other in role and mechanism. Therefore, we extend immune feedback mechanism to nonlinear PE controller. And in order to choose the optimal nonlinear PID controller games, we also propose the on-line tuning algorithm of nonlinear functions parameters in immune feedback mechanism. The trained parameters of nonlinear functions are adapted to the variations of the system parameters and any command velocity. And the adapted parameters obtained outputs of nonlinear functions with an optimal control performance. To verify performances of the proposed control systems, the speed control of nonlinear BC motor is performed. The simulation results show that the proposed control systems are effective in tracking a command velocity under system variations.

• 대한의생명과학회지
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• 제29권3호
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• pp.137-143
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• 2023

Inflammation plays an important role in immune system's response to tissue injury and biological stimuli. However, excessive inflammation can cause tissue damage. Therefore, the development of naturally derived anti-inflammatory agents have received broad attention. In this study, we investigated the anti-inflammatory mechanism of Rubi Fructus (RF) extract on the mast cell-mediated inflammatory response. To determine the regulatory mechanism of RF in inflammatory reaction, we evaluated the effects of RF on secretion of interleukin (IL)-8, IL-6 and tumor necrosis factor (TNF)-α and activation of nuclear factor-κB (NF-κB) and caspase-1 in activated human mast cells-1 (HMC-1). The results showed that RF attenuated IL-8, IL-6 and TNF-α secretion in a concentration-dependent manner. Moreover, RF significantly attenuated caspase-1and NF-κB activation in activated HMC-1. Conclusively, the present results provide evidence that RF may be a promising agent for anti-inflammatory therapy.

• 공업화학
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• 제21권4호
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• pp.366-371
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• 2010

환경 나노 기술의 빠른 발전과 함께 다양한 종류의 나노 입자에 의한 미생물 불활성화 성능이 주목 받아 왔으며, 이러한 특성을 적용한 제품들이 연구개발되어 왔다. 하지만 최근 나노 입자가 갖는 탁월한 생물학적 특성이 환경에 유익한 미생물뿐만 아니라 인간에게까지 유해한 영향을 줄 수 있다는 독성 연구 결과가 발표됨에 따라, 관련 연구자 및 일반 시민들에게 우려와 논쟁을 가져오고 있다. 본 총설에서는 이러한 나노 물질의 양면성에 대한 정확한 이해를 돕고자 기존의 연구를 중심으로 다양한 나노 입자에 의한 미생물 불활성화 특성과 메카니즘 및 응용 분야에 대해서 검토, 정리하였다.

• 식물분류학회지
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• 제50권2호
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• pp.148-153
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• 2020

Cleisostoma scolopendrifolium is an orchid species solely pollinated by the male bee Megachile yasumatsui. Although C. scolopendrifolium is an endangered species in Korea, little is known about its pollination mechanisms or the profiles of its chemical attractants. This study provides evidence that the Cleisostoma orchid attracts male bees as pollinators by mimicking female mating signals. We found 13 hydrocarbons in the Cleisostoma orchid flower presumed to be involved in sex pheromone mimicry: five alkanes (tricosane, pentacosane, heptacosane, nonacosane, and hentriacontane), compounds of cuticular hydrocarbons which function as chemical cues for the recognition of mates and species in social insects; and eight alkenes ((z)-9-tricosene, (z)-9-pentacosene, (z)-11-pentacosene, (z)-9-heptacosene, (z)-11-heptacosene, (z)-9-nonacosene, (z)-11-nonacosene, and (z)-11-hentriacontene) which serve as sex pheromones in several insects. We suggest that these hydrocarbons play a key role in the pollination mechanism between Cleisostoma orchids and Megachile bees.

• 생물정신의학
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• 제25권1호
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• pp.1-8
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• 2018

Insomnia is a common sleep-related symptom which occurs in many populations, however, the neural mechanism underlying insomnia is not yet known. The hyperarousal model explains the neural mechanism of insomnia to some extent, and the frontal cortex dysfunction has been known to be related to primary insomnia. In this review, we discuss studies that applied resting state and/or task-related functional magnetic resonance imaging to demonstrate the deficits/dysfunctions of functional activation and network in primary insomnia. Empirical evidence of the hyperarousal model and proposed relation between the frontal cortex and other brain regions in primary insomnia are examined. Reviewing these studies could provide critical insights regarding the pathophysiology, brain network and cerebral activation in insomnia and the development of novel methodologies for the diagnosis and treatment of insomnia.

• BMB Reports
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• 제48권1호
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• pp.25-29
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• 2015

Ubiquitination is a post translational modification which mostly links with proteasome dependent protein degradation. This process has been known to play pivotal roles in the number of biological events including apoptosis, cell signaling, transcription and translation. Although the process of ubiquitination has been studied extensively, the mechanism of polyubiquitination by multi protein E3 ubiquitin ligase, SCF complex remains elusive. In the present study, we identified UbcH5a as a novel stimulating factor for poly-ubiquitination catalyzed by $SCF^{hFBH1}$ using biochemical fractionations and MALDI-TOF. Moreover, we showed that recombinant UbcH5a and Cdc34 synergistically stimulate $SCF^{hFBH1}$ catalyzed polyubiquitination in vitro. These data may provide an important cue to understand the mechanism how the SCF complex efficiently polyubiquitinates target substrates.

• 한국생물정보학회:학술대회논문집
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• 한국생물정보시스템생물학회 2005년도 BIOINFO 2005
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• pp.173-182
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• 2005

A three dimensional (3D) model for the catalytic region of Type II Pseudomonas sp. USM 4-55 PHA synthase 1 (PhaC1$_{P.sp\;USM\;4-55}$) from residue 267 to residue 484 was developed. Sequence analysis demonstrated that PhaC1$_{P.sp\;USM\;4-55}$ lacked homology with all known structural databases. PSI-BLAST and HMM Superfamily analyses demonstrated that this enzyme belongs to the ${\alpha}/{\beta}$ hydrolase fold family. Threading approach revealed that the most suitable template to use was the Human gastric lipase (1HLG). The superimposition of the predicted PhaC1$_{P.sp\;USM\;4-55}$ model with the 1HLG template structure covering 86.2% of the backbone atoms showed an RMSD of 1.15 ${\AA}$ The catalytic residues comprising of Cys296, Asp451, His452 and His479 were found to be conserved and were located adjacent to each other. We proposed that the catalytic mechanism involved the formation of two tetrahedral intermediates.

• 생물정신의학
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• 제10권2호
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• pp.107-115
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• 2003

Objective:The purpose of this study was to know about the mechanism of pathogenesis of type 2 diabetes mellitus by using of blood glucose, glucoregulatory factor, insulin resistance in schizophrenic patients receiving antipsychotics. Method:Modified oral glucose tolerance tests were performed in 20 schizophrenic patients receiving haloperidol, risperidone and olanzapine. Insulin, glucagon, C-peptide and cortisol were measured in 0, 15, 45, 75 minutes after glucose loading, and insulin resistance was calculated by HOMA(homeostasis model assessment) method. Result:Olanzapine-treated patients had significant glucose elevation 45 minutes after glucose challenge. Also modest increases in HOMA IR values were detected in patients treated with olanzapine. Conclusion:Olanzapine treatment of non-diabetic patients with schizophrenia can be associated with type 2 diabetes mellitus through the elevation of glucose and insulin resistance. Elevated insulin resistance may be a causative mechanism of type 2 diabetes mellitus in patients receiving olanzapine.

• Toxicological Research
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• 제17권
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• pp.217-218
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• 2001

In a series of our screening for immunomodulating substances, we isolated prodigiosin from the culture broth qf Serratia marcescens B-1231. This compound inhibited the T cell-mediated immune responses such as concanavalin A-induced proliferation, mixed lymphocyte response, local graft versus host reaction and T-dependent antibody response at nontoxic concentrations. However. prodigiosin did not effect B cell-mediated immune functions such as lipopolysaccharide-induced proliferation and -activated polyclonal antibody production at the same concentrations. Prodigiosin did not cause death in vitro to lymphocytes at effective concentrations (＜100 nM) and also did not show toxicity in vivo to lymphoid organs at effective dos-ages (10 and 30 mg/kg). The pharmacological potencies were comparable to the activities of well-known T-cell specific immunosuppressants such as cyclosporin A. In our continuing study, mechanism of action of PDG is investigated with respect to the effect of PDG on IL-2/IL-2R pathway and transcription factor.