• Journal of Korean Tunnelling and Underground Space Association
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• v.22 no.1
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• pp.91-105
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• 2020

This study is the basic study for improving the range of influence and potency of mixing bars in the chamber of Shield TBM. Currently, there are many studies on disk cutters, cutter bits and segments in the study of the domestic Shield TBM. However, studies that mix soil and rocks that come from the membrane during the Shield TBM excavation and scatter them with screw conveyors are not as good as those abroad. In this study, the existing Shield TBM Chamber was manufactured as a miniature and the experiment. Inside the chamber, different sizes (4 mm, 6 mm, 8 mm, 10 mm) and colors (black, white, red, and blue) were used to form layers. This experiment was carried out by different shapes and sizes of RPM and mixing bars. In addition, the difference between a miniature model and a reclining one was checked to determine the effect of the direction of gravity on the mixing efficiency. This was done in the same way for all other conditions other than differences in the direction of gravity. Through this experiment, we identified the orientation of the chamber model, the size and shape of the mixing bar inside, and the mixing effect and torque depending on RPM. A comparative review of the mixing effect and torque confirmed that the shape and size of the mixing bar affect the mixing of samples, and that the direction of gravity affects torque.

• The Korean Journal of Physiology and Pharmacology
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• v.20 no.2
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• pp.213-220
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• 2016

Mast cells are primary mediators of allergic inflammation. Beta-1,3-glucan (BG) protects against infection and shock by activating immune cells. Activation of the BG receptor induces an increase in intracellular $Ca^{2+}$, which may induce exocytosis. However, little is known about the precise mechanisms underlying BG activation of immune cells and the possible role of mitochondria in this process. The present study examined whether BG induced mast cell degranulation, and evaluated the role of calcium transients during mast cell activation. Our investigation focused on the role of the mitochondrial calcium uniporter (MCU) in BG-induced degranulation. Black mouse (C57) bone marrow-derived mast cells were stimulated with $0.5{\mu}g/ml$ BG, $100{\mu}g/ml$ peptidoglycan (PGN), or $10{\mu}M$ A23187 (calcium ionophore), and dynamic changes in cytosolic and mitochondrial calcium and membrane potential were monitored. BG-induced mast cell degranulation occurred in a time-dependent manner, and was significantly reduced under calcium-free conditions. Ruthenium red, a mitochondrial $Ca^{2+}$ uniporter blocker, significantly reduced mast cell degranulation induced by BG, PGN, and A23187. These results suggest that the mitochondrial $Ca^{2+}$ uniporter has an important regulatory role in BG-induced mast cell degranulation.

• Applied Microscopy
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• v.38 no.3
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• pp.235-243
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• 2008

A compact soft x-ray microscope operated in the 'water window' wavelength region ($2.3{\sim}4.4nm$) was used for observing cells with nano-scale spatial resolution. To obtain cellular imaging captured with colloidal gold nanoparticles using a compact soft x-ray microscope. The colloidal gold nanoparticles showed higher contrast and lower transmission more than 7 times than that of cellular protein on the soft x-ray wavelength region. The structure and thickness of the cell membrane of the Coscinodiscus oculoides (diatome) and red blood cells were seen clearly. The gold nanoparticles within the HT1080 and MDA-MB 231 cells were seen clearly on the soft x-ray microscopy. The gold nanoparticles were aggregated within vesicles by endocytosis.

• Korean Journal of Ichthyology
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• v.28 no.1
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• pp.19-27
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• 2016

The RLG (relative length of gut) is 1.52 (n=12) in the sablefish, Anoplopoma fimbria. The digestive tract has five or six pyloric caeca in the posterior region of stomach. Morphology of mucosal fold is unbranched type in the esophagus and stomach, but branched type in the intestine. The histological structure of digestive tract can be divided into mucosal layer, submucosal layer, muscular layer and serous membrane in the cross section. In the esophagus, mucosal epithelial layer is a simple, and consists of ciliated columnar epithelia and mucous cells. In the stomach, gastric gland of mucosal epithelial layer is a tubular, and is composed of chief cell, parietal cell and mucin secreting cell, which is columnar and contained secretory granules of red and blue colors in the AB-PAS (pH 2.5) reaction. In the intestine, mucosal epithelial layer is a simple, and consists of ciliated columnar epithelia and goblet cells. The submucosal layer is composed mainly of collagen fibers, and well developed in the esophagus. And the muscular layer of digestive tract is divided into longitudinal and circular muscle layer, and well developed in the stomach. The liver is composed of numerous lobular structure and bile canaliculi. Stainability of hepatocyte cytoplasm was eosinophilic, and nucleus and nucleolus showed basophilic in the H-E stain. The pancreatic tissue was scattered in the fatty tissue near the digestive tract, and acinar gland consisting of numerous exocrine cells. And cytoplasmic stainability of exocrine cell was basophilic, and contained numerous zymogen granules of eosinophilic in the H-E stain.

• Biomedical Science Letters
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• v.13 no.4
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• pp.251-261
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• 2007

A myofiber of skeletal muscle is composed of myofibrils, sarcolemma (plasma membrane), and constameres, which anchor the myofibrils to the sarcolemma. Achvillin is a recently identified F-actin binding muscle protein, co-isolates with dystrophin and caveolin-3 in low-density sarcolemma of striated muscle, and colocalizes with dystrophin at costameres, the specialized adhesion sites in muscle. Archvillin also binds to nebulin and localizes at myofibrillar Z-discs, the lateral boundaries of the sarcomere in muscle. However other roles of archvillin on the dynamics of myofibrillogenesis remain to be defined. The goal of this study is, by using siRNA-mediated gene silencing technique, to investigate the effect of archvillin on the dynamics of myofibrillogenesis in cell culture of a mouse skeletal myogenic cell line (C2C12), where presumptive myoblasts withdraw from the cell cycle, fuse, undergo de novo myofibrillogenesis, and differentiate into mature myotubes. The roles of archvillin in the assembly and maintenance of myofibril and during the progression of myofibrillogenesis induced in skeletal myoblast following gene silencing in the cell culture were investigated. Fluorescence microscopy demonstrated that the distribution of archvillin was changed along the course of myofibril assembly with nebulin, vinculin and F-actin and then located at Z-lines with nebulin. Fluorescence microscopy demonstrated that knockdown of mouse archvillin expression led to an impaired assembly of new myofibrillar clusters and delayed fusion and myofibrillogenesis although the mouse archvillin siRNA did not affect those expressions of archvillin binding proteins, such as nebulin and F-actin. This result is corresponded with that of RT-PCR and western blots. When the perturbed archvillin was rescued by co-transfection with GFP or Red tagged human archvillin construct, the inhibited cell fusion and myotube formation was recovered. By using siRNA technique, archvillin was found to be involved in early stage of myofibrillogenesis. Therefore, the current data suggest the idea that archvillin plays critical roles on cell fusion and dynamic myofibril assembly.

• Journal of Veterinary Clinics
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• v.30 no.4
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• pp.301-304
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• 2013

Otic mass removal was performed in a 19-month-old, castrated domestic shorthair cat. The patient had 1- year history of recurrent otitis externa, and then otic mass in the right ear canal was found. Under general anesthesia, 2.7 mm rigid endoscope was inserted to the right ear canal with the irrigation system. The ovoid-shaped, 4.9 mm in diameter red otic mass located in the right ear canal was removed via traction-avulsion. Then, rupture of the tympanic membrane was revealed and otic flushing was performed with sterile isotonic (0.9%) saline to remove exudates. Histologically, the removed polyp was diagnosed as granulation tissue with severe ulceration. The patient didn't reveal any remarkable abnormality after surgery, and no recurrence were found after 5 months follow up. The video otoscopy seems to offer a useful option for treatment of a feline inflammatory polyp.

• Journal of Korean Society on Water Environment
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• v.22 no.2
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• pp.321-327
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• 2006

This interlaboratory study was designed to evaluate protozoan test methods in water and to predict the major causes of deviation of the methods. Each of four laboratories with previous experience of protozoa analysis in water participated, and met the initial performance criteria of EPA 1623 method provided. The protozoan analysis procedure consists of filtrations, concentration, immunomagnetic separation, dyeing (staining) and counting with observation. We tested three different filtration equipments: capsule filter for 10 L of surface water, and high volume (HV) capsule filter and membrane filter for 100 L of finished water. When the recovery of each step of the procedure was evaluated with EasySeed, the commercial stock of each 100 Cryptosporidium and Giardia, immunomagnetic separation and filtration step were the most crucial steps affecting the stability of the recovery, especially for Cryptosporidium. There was no significant difference of recovery among the filtration methods. Recovery of protozoa from source water were evaluated with spiked EasySeed as matrix tests. The recoveries of Giardia increased significantly in the matrix tests compared those in the deionized water. We also applied red stained mixture stocks of Cryptosporidium and Giardia called ColorSeed as internal standards of water sample tests. The recoveries of both EasySeed and ColorSeed in samples tested were within the range of the criteria, however, the Giardia recoveries using ColorSeed decreased significantly. Further optimization study with ColorSeed will be necessary, considering the convenience of using the internal standard without additional sample analysis. The significant factors of the recovery variation were identified as the differences of laboratories as well as water quality and type of the stock for spiking. The results of this study emphasize the importance of the quality assurance program for protozoan analysis lab in water.

• Journal of Ginseng Research
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• v.35 no.1
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• pp.92-103
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• 2011

Ginseng has been used as a general tonic agent to invigorate human body. In the present study, we isolated novel glycolipoproteins from ginseng that activate $Ca^{2+}$-activated $Cl^-$ channel (CaCC) in Xenopus oocytes and transiently increase intracellular free $Ca^{2+}$ concentration ($[Ca^{2+}]_i$) in mouse Ehrlich ascites tumor cells. We named the active ingredients as gintonin. Gintonin exists in at least six different forms. The native molecular weight of gintonin is about 67 kDa but its apparent molecular weight is about 13 kDa, indicating that gintonin might be a pentamer. Gintonin is rich in hydrophobic amino acids. Its main carbohydrates are glucose and glucosamine. Its lipid components are linoleic, palmitic, oleic, and stearic acids. Gintonin actions were blocked by U73122, a phospholipase C inhibitor, 2-aminoethxydiphenyl borate, an inositol 1,4,5-trisphosphate receptor antagonist, or bis (o-aminophenoxy) ethane-N,N,N0,N0-tetracetic acid acetoxymethyl ester, a membrane permeable $Ca^{2+}$ chelator. In the present study, we for the first time isolated novel gintonin and showed the signaling pathways on gintonin-mediated CaCC activations and transient increase of $[Ca^{2+}]_i$. Since $[Ca^{2+}]_i$ as a second messenger plays a pivotal role in the regulation of diverse $Ca^{2+}$-dependent intracellular signal pathways, gintonin-mediated regulations of $[Ca^{2+}]_i$ might contribute to biological actions of ginseng.

• Journal of Ginseng Research
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• v.41 no.3
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• pp.392-402
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• 2017

Background: Previously, we reported that Korean Red Ginseng inhibited liver fibrosis in mice and reduced the expressions of fibrogenic genes in hepatic stellate cells (HSCs). The present study was undertaken to identify the major ginsenoside responsible for reducing the numbers of HSCs and the underlying mechanism involved. Methods: Using LX-2 cells (a human immortalized HSC line) and primary activated HSCs, MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide) assays were conducted to examine the cytotoxic effects of ginsenosides. $H_2O_2$ productions, glutathione contents, lactate dehydrogenase activities, mitochondrial membrane permeabilities, apoptotic cell subpopulations, caspase-3/-7 activities, transferase dUTP nick end labeling (TUNEL) staining, and immunoblot analysis were performed to elucidate the molecular mechanism responsible for ginsenoside-mediated cytotoxicity. Involvement of the AMP-activated protein kinase (AMPK)-related signaling pathway was examined using a chemical inhibitor and small interfering RNA (siRNA) transfection. Results and conclusion: Of the 11 ginsenosides tested, 20S-protopanaxadiol (PPD) showed the most potent cytotoxic activity in both LX-2 cells and primary activated HSCs. Oxidative stress-mediated apoptosis induced by 20S-PPD was blocked by N-acetyl-$\text\tiny L$-cysteine pretreatment. In addition, 20S-PPD concentration-dependently increased the phosphorylation of AMPK, and compound C prevented 20S-PPD-induced cytotoxicity and mitochondrial dysfunction. Moreover, 20S-PPD increased the phosphorylation of liver kinase B1 (LKB1), an upstream kinase of AMPK. Likewise, transfection of LX-2 cells with LKB1 siRNA reduced the cytotoxic effect of 20S-PPD. Thus, 20S-PPD appears to induce HSC apoptosis by activating LKB1-AMPK and to be a therapeutic candidate for the prevention or treatment of liver fibrosis.

• The Korean Journal of Physiology and Pharmacology
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• v.19 no.1
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• pp.65-71
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• 2015

Asthma is a chronic inflammatory disease characterized by airway hyperresponsiveness (AHR) and reversible airway obstruction. Methacholine (MCh) is widely used in broncho-provocation test to evaluate airway resistance. For experimental investigation, ovalbumin-induced sensitization is frequently used in rodents (Ova-asthma). However, albeit the inflammatory histology and AHR in vivo, it remains unclear whether the MCh sensitivity of airway smooth muscle isolated from Ova-asthma is persistently changed. In this study, the contractions of airways in precision-cut lung slices (PCLS) from control, Ova-asthma, and IL-13 overexpressed transgenic mice (IL-13TG) were compared by analyzing the airway lumen space (AW). The airway resistance in vivo was measured using plethysmograph. AHR and increased inflammatory cells in BAL fluid were confirmed in Ova-asthma and IL-13TG mice. In the PCLS from all three groups, MCh concentration-dependent narrowing of airway lumen (${\Delta}AW$) was observed. In contrast to the AHR in vivo, the $EC_{50}$ of MCh for ${\Delta}AW$ from Ova-asthma and IL-13TG were not different from control, indicating unchanged sensitivity to MCh. Although the AW recovery upon MCh-washout showed sluggish tendency in Ova-asthma, the change was also statistically insignificant. Membrane depolarization-induced ${\Delta}AW$ by 60 mM $K^+$ (60K-contraction) was larger in IL-13TG than control, whereas 60K-contraction of Ova-asthma was unaffected. Furthermore, serotonin-induced ${\Delta}AW$ of Ova-asthma was smaller than control and IL-13TG. Taken together, the AHR in Ova-asthma and IL-13TG are not reflected in the contractility of isolated airways from PCLS. The AHR of the model animals seems to require intrinsic agonists or inflammatory microenvironment that is washable during tissue preparation.