• Tunnel and Underground Space
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• v.34 no.2
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• pp.89-103
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• 2024

In the disposal environment, gases can be generated at the interface between canister and buffer due to various factors such as anaerobic corrosion, radiolysis, and microbial degradation. If the gas generation rate exceeds the diffusion rate, the gas within the buffer may compress, resulting in physical damage to the buffer due to the increased pore pressure. In particular, the rapid movement of gases, known as gas breakthroughs, through the dilatancy pathway formed during this process may lead to releasing radionuclide. Therefore, understanding these gas generation and movement mechanism is essential for the safety assessment of the disposal systems. In this study, an experimental apparatus for investigating gas migration within buffer was constructed based on a literature review. Subsequently, a gas injection experiment was conducted on a compacted bentonite block made of Bentonile WRK (Clariant Ltd.) powder. The results clearly demonstrated a sharp increase in stress and pressure typically observed at the onset of gas breakthrough within the buffer. Additionally, the range of stresses induced by the swelling phenomenon of the buffer, was 4.7 to 9.1 MPa. The apparent gas entry pressure was determined to be approximately 7.8 MPa. The equipment established in this study is expected to be utilized for various experiments aimed at building a database on the initial properties of buffer and the conditions during gas injection, contributing to understanding the gas migration phenomena.

• Journal of Ginseng Research
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• v.47 no.5
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• pp.627-637
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• 2023

Background: Damage to the healthy intestinal epithelial layer and regulation of the intestinal immune system, closely interrelated, are considered pivotal parts of the curative treatment for inflammatory bowel disease (IBD). Plant-based diets and phytochemicals can support the immune microenvironment in the intestinal epithelial barrier for a balanced immune system by improving the intestinal microecological balance and may have therapeutic potential in colitis. However, there have been only a few reports on the therapeutic potential of plant-derived exosome-like nanoparticles (PENs) and the underlying mechanism in colitis. This study aimed to assess the therapeutic effect of PENs from Panax ginseng, ginseng-derived exosome-like nanoparticles (GENs), in a mouse model of IBD, with a focus on the intestinal immune microenvironment. Method: To evaluate the anti-inflammatory effect of GENs on acute colitis, we treated GENs in Caco2 and lipopolysaccharide (LPS) -induced RAW 264.7 macrophages and analyzed the gene expression of proinflammatory cytokines and anti-inflammatory cytokines such as TNF-α, IL-6, and IL-10 by real-time PCR (RT-PCR). Furthermore, we further examined bacterial DNA from feces and determined the alteration of gut microbiota composition in DSS-induced colitis mice after administration of GENs through 16S rRNA gene sequencing analysis. Result: GENs with low toxicity showed a long-lasting intestinal retention effect for 48 h, which could lead to effective suppression of pro-inflammatory cytokines such as TNF-α and IL-6 production through inhibition of NF-κB in DSS-induced colitis. As a result, it showed longer colon length and suppressed thickening of the colon wall in the mice treated with GENs. Due to the amelioration of the progression of DSS-induced colitis with GENs treatment, the prolonged survival rate was observed for 17 days compared to 9 days in the PBS-treated group. In the gut microbiota analysis, the ratio of Firmicutes/Bacteroidota was decreased, which means GENs have therapeutic effectiveness against IBD. Ingesting GENs would be expected to slow colitis progression, strengthen the gut microbiota, and maintain gut homeostasis by preventing bacterial dysbiosis. Conclusion: GENs have a therapeutic effect on colitis through modulation of the intestinal microbiota and immune microenvironment. GENs not only ameliorate the inflammation in the damaged intestine by downregulating pro-inflammatory cytokines but also help balance the microbiota on the intestinal barrier and thereby improve the digestive system.

• Journal of the Korea institute for structural maintenance and inspection
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• v.13 no.6 s.58
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• pp.192-203
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• 2009

In the new Seoul-Busan high speed railroad construction specially in area of city center passage the roadbed establishment is recommended the staibility for the existing subway tunnel segments of Busan subway 1st and 2nd lines regarding the appearance condition, a quality condition and the durability of the objective facility, and it evaluates the numerical analysis using MIDAS/GTS which leads the stability of the objective facility and investigatesd tunnels. Fundamental issues in tunneling under high groundwater table are discussed and the effect of groundwater on tunnel excavation was examined using a 3D stress-pore pressure coupled Finite-Element Method. Based on the results the interaction mechanism between the tunnelling and groundwater is identified. In the both of 1st and 2nd Line the maximum sinkage, unequal sinkage and the lining stress from numerical analysis are within permission and the damage degree is appearing to be disregarded. But it enforces necessary Pre-grouting in order to minimize an actual tunnel face conduct and when the tunnel is excavated it is also necessary to minimize the outflow possibility.

• Journal of Korean Medical classics
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• v.37 no.3
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• pp.83-106
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• 2024

Objectives : This paper aims to examine the meaning of Shengmaisan in relation to original qi based on the discussion of Zhangyuansu, Lidongyuan and other doctors. Methods : Discussion of Shengmaisan made by Zhang, Li and others were examined. Afterwards, the medicinal properties of renshen, maimendong, and wuweizi as written in the Bencaogangmu, Donguibogam, Benjingshuzheng and texts of Zhang and Li were studied in relation to original qi. Related concepts such as '肺中伏火'·'補肺中元氣不足'·'補天眞元氣'·'夏食寒' were analyzed as well. Results & Conclusions : 1. Various pathology related to deficiency in original qi could act as internal pathogen for Shengmaisan application with which external factors such as summerheat and dampness heat meet results in most damage in the Lung metal. Therefore the upper body Lung is emphasized as pathogen. 2. The pathology of Shengmaisan application is depletion of humor, which should be refined, due to summer or dampness heat in a state of original qi deficiency which damages the Lungs, disabling its function of managing clear and pure qi. 3. The disease pattern for Shengmaisan in relation to original qi, according to other doctors, includes symptoms related to the Lungs such as dryness in the mouth due to excessive perspiration, blankness, loss of consciousness, shortness of breath, coughing, fast breathing, along with general bodily symptoms such as heavy sensation of the body, lethargy, difficulty walking, limping. These general bodily symptoms are due to either qi deficiency of the Lung, or humor deficiency due to failure of qi convergence in the lower body, or symptoms caused by Jing deficiency in severe cases. Symptoms related to problems in the lower body could manifest as dysfunction in urination and defecation, weakness in the limbs caused by original qi deficiency. 4. The Lungs circulate the clear and pure qi, converging qi and creating humor to assist the Triple Burner's Qi-Humor metabolism, enabling smooth communication of original qi throughout the body. With the original qi well tonified, the shen mechanism which is rooted in original qi allows for autonomous and consistent qi circulation within the body. Therefore, both Zhang and Li emphasized the importance of original qi. The property of Shengmaisan is explained as 'supplement qi/create liquid, convergence of yin/stop perspiration'. Zhang and Li explained its property as managing the circulation of original qi, to tonify Lungs' original qi and origin of water-humor.

• International Journal of Stem Cells
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• v.15 no.2
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• pp.203-216
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• 2022

Background and Objectives: Epidemiological investigations have shown positive correlations between increased diesel exhaust particles (DEP) in ambient air and adverse health outcomes. DEP are the major constituent of particulate atmospheric pollution and have been shown to induce proinflammatory responses both in the lung and systemically. Here, we report the effects of DEP exposure on the properties of human Wharton's jelly-derived mesenchymal stem cells (WJ-MSCs), including stemness, regeneration, and immunomodulation. Methods and Results: Non-apoptotic concentrations of DEP (10 ㎍/ml) inhibited the migration and osteogenic differentiation capacity of WJ-MSCs. Gene expression profiling showed that DEP increased intracellular reactive oxygen species (ROS) and expression of pro-inflammatory and metabolic-process-related genes including cFos. Furthermore, WJ-MSCs cultured with DEP showed impaired suppression of T cell proliferation that was reversed by inhibition of ROS or knockdown of cFos. ERK inhibition assay revealed that DEP-induced ROS regulated cFos through activation of ERK but not NF-κB signaling. Overall, low concentrations of DEP (10 ㎍/ml) significantly suppressed the stemness and immunomodulatory properties of WJ-MSCs through ROS/ERK/cFos signaling pathways. Furthermore, WJ-MSCs cultured with DEP impaired the therapeutic effect of WJ-MSCs in experimental colitis mice, but was partly reversed by inhibition of ROS. Conclusions: Taken together, these results indicate that exposure to DEP enhances the expression of pro-inflammatory cytokines and immune responses through a mechanism involving the ROS/ERK/cFos pathway in WJ-MSCs, and that DEP-induced ROS damage impairs the therapeutic effect of WJ-MSCs in colitis. Our results suggest that modulation of ROS/ERK/cFos signaling pathways in WJ-MSCs might be a novel therapeutic strategy for DEP-induced diseases.

• Clinical and Experimental Pediatrics
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• v.51 no.10
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• pp.1102-1111
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• 2008

Purpose : Resveratrol, extracted from red wine and grapes, has an anti-cancer effect, an antiinflammatory effect, and an antioxidative effect mainly in heart disease and also has neuroprotective effects in the adult animal model. No studies for neuroprotective effects during the neonatal periods have been reported. Therefore, we studied the neuroprotective effect of resveratrol on hypoxic-ischemic brain damage in neonatal rats via anti-apoptosis. Methods : Embryonic cortical neuronal cell culture of rat brain was performed using pregnant Sprague-Dawley (SD) rats at 18 days of gestation (E18) for the in vitro approach. We injured the cells with hypoxia and administered resveratrol (1, 10, and $30{\mu}g/mL$) to the cells at 30 minutes before hypoxic insults. In addition, unilateral carotid artery ligation with hypoxia was induced in 7-day-old neonatal rats for the in vivo approach. We injected resveratrol (30 mg/kg) intraperitoneally into animal models. Real-time PCR and Western blotting were performed to identify the neuroprotective effects of resveratrol through anti-apoptosis. Results : In the in vitro approach of hypoxia, the expression of Bax, caspase-3, and the ratio of Bax/Bcl-2, indicators of the level of apoptosis, were significantly increased in the hypoxia group compared to the normoxia group. In the case of the resveratrol-treated group, expression was significantly decreased compared to the hypoxia group. And the results in the in vivo approach were the same as in the in vitro approach. Conclusion : The present study demonstrates that resveratrol plays neuroprotective role in hypoxic-ischemic brain damage during neonatal periods through the mechanism of anti-apoptosis.

• Sleep Medicine and Psychophysiology
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• v.7 no.1
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• pp.60-66
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• 2000

Objectives: The Psychopathology of schizophrenia was expected to be related with focal dysfunction of brain while schizophrenia is recognized and studied as the brain disease. Authors studied correlation between neuropsychological tests and delusion which is representative symptom of schizophrenia in patients with head trauma and psychiatric patients in order to explore the functional localization of brain in delusional symptom. Methods: Halstead Reitan Neuropsychological Test Battery and Korean Weschler Intelligent Scale and Minnesota Multiphasic Personality Inventory(MMPI) were administered to one hundred ninteen patients consisted of sixty nine psychiatric patients and fifty patients with brain damage. We tested correlation between results of neuropsychological tests and delusional scale made from twenty four items related with delusion in MMPI. T-test between eighteen higher delusion scorers and twenty one lower scorers was examed in psychiatric group. Results: In brain damage group, signigicant correlations were found in the tests related with function of frontal lobe such as category test, trail making AB test, tactual performance test, digit symbol test and fingertip number writing test, and significant correlations were also noted in the tests related with function of left temporal and parietal lobes such as information, comprehension, vocabulary, similarities and speech sound perception test. The tests related with the function of right hemisphere such as tactual performance test location, picture completion and performance, and the tests related with subcortical function such as arithmetic, digit span, attention, digit symbol test, digit symbol and trail making AB test were signigicantly corelated with delusional scale too. In psychiatric group there were significant difference of delusional score in the tests related with function of left hemisphere such as vocabulary, vocable IQ, comprehension and language, and in the tests related with subcortical function such as N 120 voltage, digit symbol and arithmetic. Conclusions: Delusion seems to be related with function of frontal lobe, left hemisphere and subcortex in both groups. Right hemisphere may be also partially related with delusion.

• Toxicological Research
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• v.24 no.3
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• pp.175-182
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• 2008

DNA-dependent protein kinase(DNA-PK) is involved in joining DNA double-strand breaks induced by ionizing radiation or V(D)J recombination and is activated by DNA ends and composed of a DNA binding subunit, Ku, and a catalytic subunit, DNA-PKcs. It has been suggested that DNA-PK might be $2^{nd}$ upstream kinase for protein kinase B(PKB). In this report, we showed that Ser473 phosphorylation in the hydrophobic-motif of PKB is blocked in DNA-PK knockout mouse embryonic fibroblast cells(MEFs) following insulin stimulation, while there is no effect on Ser473 phosphorylation in DNA-PK wild type MEF cells. The observation is further confirmed in human glioblastoma cells expressing a mutant form of DNA-PK(M059J) and a wild-type of DNA-PK(M059K), indicating that DNA-PK is indeed important for PKB activation. Furthermore, the treatment of cells with doxorubicin, DNA-damage inducing agent, leads to PKB phosphorylation on Ser473 in control MEF cells while there is no response in DNA-PK knockout MEF cells. Together, these results proposed that DNA-PK has a potential role in insulin signaling as well as DNA-repair signaling pathway.

• Tuberculosis and Respiratory Diseases
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• v.41 no.4
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• pp.319-327
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• 1994

Background: The pathogenetic mechanism of adult respiratory distress syndrome(ARDS) is not clearly defined yet, but it is well known that increased pulmonary capillary permeabilty is characteristic feature of ARDS. The increased alveolar-capillary permeability is usually preceded by damage of pulmonary artery endothelial cells. The released enzymes and oxygen free radicals from the activated neutrophils seem to play a predominant role in endothelial cell cytotoxicity. The activated neutrophils, however, probably are not the sole contributing factor in this type of damage because many cases of ARDS have been reported in severe neutropenia. Bacterial endotoxin perse and/or oxygen free radicals released from endothelial cells are suggested to be possible factors that contribute to the development of ARDS. The purpose of this study is to investigate the direct cytotoxicity of endotoxin and the role of oxygen free radicals released from the endothelial cells in endotoxin-induced endothelial cell cytotoxicity. Methods: First, to investigate whether endotoxin is cytotoxic to HUVE by itself, various doses of endotoxin were added to culture medium and cytotoxicity was measured. Second, to evaluate the possible role of oxygen free radical in endotoxin-induced HUVE cytotoxicity, various antioxidants were added on the endotoxin-induced HUVE cytotoxicity and cytotoxicity was measured. Third, to verify the release of oxygen free radicals from HUVE, the concentrations of hydrogen peroxide in the endotoxin-treated culture supernatant were measured. Finally, to observe the cytotoxic effect of hydrogen peroxide, HUVE cytotoxicity in the presence of various doses of hydrogen peroxide was measured. The fourth generations of subcultured HUVE from primary culture were used. The cell cytotoxicity was quantified by the chromium-51 release assay. Results: 1) Endotoxin alone showed HUVE cytotoxicity in a dose-dependent fashion. 2) Endotoxin-induced HUVE cytotoxicity was significantly attenuated by the pretreatment of catalase and DMTU. 3) Hydrogen peroxide was released from HUVE after endotoxin treatment in a dose-dependent fashion. 4) Exogenous hydrogen peroxide also showed HUVE cytotoxicity in a dose-dependent fashion. Conclusion: These results suggest that endotoxin alone can directly injure HUVE, and, oxygen-free radicals released from HUVE in response to endotoxin may also participate in the endotoxin-induced HUVE cytotoxicity.

• Journal of the Korea Concrete Institute
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• v.25 no.5
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• pp.485-496
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• 2013

In recent years, frequent terror or military attacks by explosion or impact accidents have occurred. Examplary case of these attacks were World Trade Center collapse and US Department of Defense Pentagon attack on Sept. 11 of 2001. These attacks of the civil infrastructure have induced numerous casualties and property damage, which raised public concerns and anxiety of potential terrorist attacks. However, a existing design procedure for civil infrastructures do not consider a protective design for extreme loading scenario. Also, the extreme loading researches of prestressed concrete (PSC) member, which widely used for nuclear containment vessel, gas tank, bridges, and tunnel, are insufficient due to experimental limitations of loading characteristics. To protect concrete structures against extreme loading such as explosion and impact with high strain rate, understanding of the effect, characteristic, and propagation mechanism of extreme loadings on structures is needed. Therefore, in this paper, to evaluate the impact resistance capacity and its protective performance of bi-directional unbonded prestressed concrete member, impact tests were carried out on $1400mm{\times}1000mm{\times}300mm$ for reinforced concrete (RC), prestressed concrete without rebar (PS), prestressed concrete with rebar (PSR, general PSC) specimens. According to test site conditions, impact tests were performed with 14 kN impactor with drop height of 10 m, 5 m, 4 m for preliminary tests and 3.5 m for main tests. Also, in this study, the procedure, layout, and measurement system of impact tests were established. The impact resistance capacity was measured using crack patterns, damage rates, measuring value such as displacement, acceleration, and residual structural strength. The results can be used as basic research references for related research areas, which include protective design and impact numerical simulation under impact loading.