• Biomolecules & Therapeutics
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• v.25 no.5
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• pp.490-496
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• 2017

Imatinib resistance has become a major clinical problem for chronic myeloid leukemia. The aim of the present study was to investigate the involvement of MEG3, a lncRNA, in imatinib resistance and demonstrate its underlying mechanisms. RNAs were extracted from CML patients' peripheral blood cells and human leukemic K562 cells, and the expression of MEG3 was measured by RT-qPCR. Cell proliferation and cell apoptosis were evaluated. Western blotting was used to measure the protein expression of several multidrug resistant transporters. Luciferase reporter assay was performed to determine the binding between MEG3 and miR-21. Our results showed that MEG3 was significantly decreased in imatinib-resistant CML patients and imatinib-resistant K562 cells. Overexpression of MEG3 in imatinib-resistant K562 cells markedly decreased cell proliferation, increased cell apoptosis, reversed imatinib resistance, and reduced the expression of MRP1, MDR1, and ABCG2. Interestingly, MEG3 binds to miR-21. MEG3 and miR-21 were negatively correlated in CML patients. In addition, miR-21 mimics reversed the phenotype of MEG3-overexpression in imatinib-resistant K562 cells. Taken together, MEG3 is involved in imatinib resistance in CML and possibly contributes to imatinib resistance through regulating miR-21, and subsequent cell proliferation, apoptosis and expression of multidrug resistant transporters.

• Korean Journal of Microbiology
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• v.53 no.4
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• pp.326-328
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• 2017

Herbaspirillum sp. meg3 belonging to Betaproteobacteria was isolated from soil in Jeju island. Here, we report the complete genome sequence of strain meg3 with a size of approximately 5.47 Mb and a mean G + C content of 57.1%. The genome included 4,816 coding sequences, and 9 ribosomal RNA and 51 transfer RNA genes. In the genome, two incomplete prophage regions have been identified. Also, we propose that strain meg3 has a potential capability for aromatic-compounds degradation based on the result of genome analysis.

• Journal of Korean Neurosurgical Society
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• v.52 no.5
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• pp.466-471
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• 2012

Objective : The aim of this study was to devise an objective clustering method for magnetoencephalography (MEG) interictal spike sources, and to identify the prognostic value of the new clustering method in adult epilepsy patients with cortical dysplasia (CD). Methods : We retrospectively analyzed 25 adult patients with histologically proven CD, who underwent MEG examination and surgical resection for intractable epilepsy. The mean postoperative follow-up period was 3.1 years. A hierarchical clustering method was adopted for MEG interictal spike source clustering. Clustered sources were then tested for their prognostic value toward surgical outcome. Results : Postoperative seizure outcome was Engel class I in 6 (24%), class II in 3 (12%), class III in 12 (48%), and class IV in 4 (16%) patients. With respect to MEG spike clustering, 12 of 25 (48%) patients showed 1 cluster, 2 (8%) showed 2 or more clusters within the same lobe, 10 (40%) showed 2 or more clusters in a different lobe, and 1 (4%) patient had only scattered spikes with no clustering. Patients who showed focal clustering achieved better surgical outcome than distributed cases (p=0.017). Conclusion : This is the first study that introduces an objective method to classify the distribution of MEG interictal spike sources. By using a hierarchical clustering method, we found that the presence of focal clustered spikes predicts a better postoperative outcome in epilepsy patients with CD.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2009.05a
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• pp.71-72
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• 2009

행동활성화체계(BAS)/ 행동억제체계(BIS)는 서로 독립적이고 구분되는 신경 기저와 작용 방식을 가졌기 때문에 사람들은 이 두 체계에서 각기 독립적인 민감성을 보이리라고 가정할 수 있으며, 개인의 기질이나 성격 특성 및 광범위한 전반적 정서 경험 경향성과도 밀접하게 관련된다고 가정된다. 본 연구에서는 뇌자도(MEG)에서 취득한 신호를 가지고 EEG에서 얻은 신호 및 자기 보고식 질문지를 통한 비교 분석 연구를 수행하였다. 총 9명 (male=6, female=3)을 대상으로 EEG/MEG를 수행한 후 BIS/BAS 질문지를 수행하여 비교 분석하였다. 자기 보고식 질문지와 EEG/MEG와의 상관관계 및 통계분석을 통하여 EEG와 MEG에서 일치성 및 상관성을 살펴보고 향후 성격 및 감성성향 판단 및 분류에 있어서 MEG의 효용성 측면을 살펴보고자 함이 본 연구의 목적이다.

• Korean Chemical Engineering Research
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• v.58 no.4
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• pp.635-641
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• 2020

In this study, phase equilibria and formation behaviors of methane hydrate containing mono-ethylene glycol (MEG) and salts (sodium chloride, NaCl; sodium bromide, NaBr; sodium iodide, NaI) are investigated. Equilibrium conditions of methane hydrate containing MEG and salts are measured in a temperature range 272~283 K and a pressure range 3.5~11 MPa. Hydrate inhibition performance in the presence of additives can be summarized as follows: methane hydrate containing (5 wt% NaCl + 10 wt% MEG) > (5 wt% NaBr + 10 wt% MEG) > (5 wt% NaI + 10 wt% MEG). Formation behaviors of methane hydrate with MEG and salts are investigated for analyzing the induction time, gas consumption amount and growth rate of methane hydrates. There are no significant changes in the induction time during methane hydrate formation, but the addition of MEG and salts solution during hydrate formation can affect the gas consumption amount and growth rate.

• Korean Journal of Microbiology
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• v.54 no.3
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• pp.280-282
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• 2018

Pseudoalteromonas sp. meg-B1 belonging to Gammaproteobacteria was isolated from marine sediment in Jeju island. Here, we report the draft genome sequence of strain meg-B1 with a size of approximately 4.15 Mbp and a mean G + C content of 41.2%. The draft genome included 3,606 coding sequences, and 9 ribosomal RNA and 94 transfer RNA genes. In the draft genome, genes (e.g. choline dehydrogenase) involved in the accumulation of compatible solutes required for survival in marine environments have been identified.

• IMMUNE NETWORK
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• v.24 no.2
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• pp.3.1-3.23
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• 2024

Cigarette smoke extract (CSE)-treated mouse airway epithelial cells (MAECs)-derived exosomes accelerate the progression of chronic obstructive pulmonary disease (COPD) by upregulating triggering receptor expressed on myeloid cells 1 (TREM-1); however, the specific mechanism remains unclear. We aimed to explore the potential mechanisms of CSE-treated MAECs-derived exosomes on M1 macrophage polarization and pyroptosis in COPD. In vitro, exosomes were extracted from CSE-treated MAECs, followed by co-culture with macrophages. In vivo, mice exposed to cigarette smoke (CS) to induce COPD, followed by injection or/and intranasal instillation with oe-TREM-1 lentivirus. Lung function and pathological changes were evaluated. CD68⁺ cell number and the levels of iNOS, TNF-α, IL-1β (M1 macrophage marker), and pyroptosis-related proteins (NOD-like receptor family pyrin domain containing 3, apoptosis-associated speck-like protein containing a caspase-1 recruitment domain, caspase-1, cleaved-caspase-1, gasdermin D [GSDMD], and GSDMD-N) were examined. The expression of maternally expressed gene 3 (MEG3), spleen focus forming virus proviral integration oncogene (SPI1), methyltransferase 3 (METTL3), and TREM-1 was detected and the binding relationships among them were verified. MEG3 increased N6-methyladenosine methylation of TREM-1 by recruiting SPI1 to activate METTL3. Overexpression of TREM-1 or METTL3 negated the alleviative effects of MEG3 inhibition on M1 polarization and pyroptosis. In mice exposed to CS, EXO^-CSE further aggravated lung injury, M1 polarization, and pyroptosis, which were reversed by MEG3 inhibition. TREM-1 overexpression negated the palliative effects of MEG3 inhibition on COPD mouse lung injury. Collectively, CSE-treated MAECs-derived exosomal long non-coding RNA MEG3 may expedite M1 macrophage polarization and pyroptosis in COPD via the SPI1/METTL3/TREM-1 axis.

• Journal of Science Education
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• v.33 no.2
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• pp.336-345
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• 2009

The purpose of this study is to analysis ERF components patterns of causal questions generated during the observation of biological phenomenon. First, the system that shows pictures causing causal questions based on biological phenomenon (evoked picture system) was developed in a way of cognitive psychology. The ERF patterns of causal questions based on time-series brain processing was observed using MEG. The evoked picture system was developed by R&D method consisting of scientific education experts and researchers. Tasks were classified into animal (A), microbe (M), and plant (P) tasks according to biological species and into interaction (I), all (A), and part (P) based on the interaction between different species. According to the collaboration with MEG team in the hospital of Seoul National University, the paradigm of MEG task was developed. MEG data about the generation of scientific questions in 5 female graduate student were collected. For examining the unique characteristic of causal question, MEG ERF components were analyzed. As a result, total 100 pictures were produced by evoked picture and 4 ERF components, M1(100~130ms), M2(220~280ms), M3(320~390ms), M4(460~520ms). The present study could guide personalized teaching-learning method through the application and development of scientific question learning program.

• Journal of The Korean Association For Science Education
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• v.30 no.8
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• pp.1097-1109
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• 2010

The purpose of this study is to analyze the ERF components patterns of observers who have different cognitive styles using magneto-encephalography (MEG). The task was developed based on the CSA (Cognitive Style Analysis) program. Eight right-handed, healthy male college students participated in voluntarily. To investigate college students' ERF components during the task, an MEG system with block design was used to measure magnetic signals in their brains. For examining the observation characteristic by cognitive style, MEG ERF components were analyzed. As a result, four ERF components (M1, M2, M3, M4) were observed. Through the results of this study, the reason for different observation characteristics by cognitive styles was verified in the neurophysiological methods. This study will have implications to establish theories on scientific observation and cognitive styles.

• Journal of the Korean Institute of Gas
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• v.24 no.5
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• pp.56-64
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• 2020

This study presents the hydrate induction time of PVCap according to subcooling temperature, salt concentration, and MEG concentration in order to analyze the inhibition effect of PVCap in various production environments of offshore gas fields. A high-pressure hydrate generator was made for the hydrate formation experiments. It was verified that the apparatus had sufficient reliability by comparing the results of hydrate equilibrium conditions and induction time from the apparatus with published reference data. As the subcooling temperature increased from 6.1℃ to 12.1℃, the induction time of PVCap concentration of 0.1~1 wt% decreased. When the salt concentration increased from 3 wt% to 7 wt%, the induction time was reduced by up to 78% under the condition of 0.5 wt% PVCap due to polymer structure degradation by salt effect. In the case of HHI (hybrid hydrate inhibitor) made by mixing MEG 10 wt% and PVCap, the change in induction time was not large compared to PVCap 1 wt% due to the under-inhibition effect. On the other hand, the hydrate inhibition efficiency of HHI with MEG 20wt% increased 1.7 times compared to PVCap.