• Journal of Ginseng Research
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• v.42 no.1
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• pp.75-80
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• 2018

Background: The aim of the present study was to evaluate the potential protective effects of six ginsenosides (Rb1, Rb2, Rc, Rd, Rg1, and Rg3) isolated from Panax ginseng against tacrolimus (FK506)-induced apoptosis in renal proximal tubular LLC-PK1 cells. Methods: LLC-PK1 cells were treated with FK506 and ginsenosides, and cell viability was measured. Protein expressions of mitogen-activated protein kinases, caspase-3, and kidney injury molecule-1 (KIM-1) were evaluated by Western blotting analyses. The number of apoptotic cells was measured using an image-based cytometric assay. Results: Reduction in cell viability by $60{\mu}M$ FK506 was ameliorated significantly by cotreatment with ginsenosides Rg1 and Rb1. The phosphorylation of p38, extracellular signal-regulated kinases, and KIM-1, and cleavage of caspase-3, increased markedly in LLC-PK1 cells treated with FK506 and significantly decreased after cotreatment with ginsenoside Rb1. The number of apoptotic cells decreased by 6.0% after cotreatment with ginsenoside Rb1 ($10{\mu}M$ and $50{\mu}M$). Conclusion: The antiapoptotic effects of ginsenoside Rb1 on FK506-induced apoptosis were mediated by the inhibition of mitogen-activated protein kinases and caspase activation.

• Preventive Nutrition and Food Science
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• v.17 no.2
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• pp.101-108
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• 2012

Interruption or prolonged reduction and subsequent restoration of blood flow into the kidney triggers the generation of a burst of reactive oxygen species (ROS), leading to injury in the tubular epithelial cells. In this study, we determined whether methanol extract of goat's-beard (Aruncus dioicus) (extract) could prevent this ischemia/reperfusion injury. When in vitro radical scavenging activity of the extract was measured using a DPPH radical quenching assay, the extract displayed slightly lower activity than ascorbic acid. One hour after administration of the extract (400 mg/kg) by intraperitoneal injection in rats, renal ischemia/reperfusion injury was generated by clamping the left renal artery for forty minutes, followed by 24 hr restoration of blood circulation. Prior to clamping the left renal artery, the right renal artery was removed. Compared with the vehicle-treated group, pretreatment with the extract significantly reduced the tubular epithelial cell injury by 37% in the outer medulla region, and consequently reduced serum creatinine concentration by 39%. Reduction in the cell injury was mediated by attenuation of Bax/Bcl-2 ratio, inhibition of caspase-3 activation from procaspase-3, and subsequent reduction in the number of apoptotic cells. Thus, goat's-beard (Aruncus dioicus) might be developed as a prophylactic agent to prevent acute kidney injury.

• The Korean Journal of Physiology and Pharmacology
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• v.27 no.3
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• pp.257-265
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• 2023

Kidney ischemia/reperfusion (I/R) injury, a common cause of acute kidney injury (AKI), is associated with the migration of inflammatory cells into the kidney. Ras-related C3 botulinum toxin substrate 1 (Rac1), a member of the Rho family of small GTPase, plays an important role in inflammatory cell migration by cytoskeleton rearrangement. Here, we investigated the role of Rac1 on kidney I/R injury and macrophage migration. Male mice were subjected to either 25 min of bilateral ischemia followed by reperfusion (I/R) or a sham operation. Some mice were administrated with either NSC23766, an inhibitor of Rac1, or 0.9% NaCl (vehicle). Kidney damage and Rac1 activity and expression were measured. The migration and lamellipodia formation of RAW264.7 cells, mouse monocyte/macrophage, induced by monocyte chemoattractant protein-1 (MCP-1, a chemokine) were determined using transwell migration assay and phalloidin staining, respectively. In sham-operated kidneys, Rac1 was expressed in tubular cells and interstitial cells. In I/R-injured kidneys, Rac1 expression was decreased in tubule cells in correlation with the damage of tubular cells, whereas Rac1 expression increased in the interstitium in correlation with an increased population of F4/80 cells, monocytes/macrophages. I/R increased Rac1 activity without changing total Rac1 expression in the whole kidney lysates. NSC23766 administration blocked Rac1 activation and protected the kidney against I/R-induced kidney damage and interstitial F4/80 cell increase. NSC23766 suppressed monocyte MCP-1-induced lamellipodia and filopodia formation and migration of RAW 264.7 cells. These results indicate Rac1 inhibition protects the kidney against I/R via inhibition of monocytes/macrophages migration into the kidney.

• Journal of Life Science
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• v.24 no.4
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• pp.337-342
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• 2014

Resveratrol (RSV), a natural polyphenolic compound, is a modulator for cell division and cell migration, and has diverse beneficial properties. Angiogenin (ANG) and vascular endothelial growth factor (VEGF) are considered to be important mechanisms for cell proliferation, angiogenesis, the formation of tubular structures, and migration. In this study, we investigated whether RSV has a migratory effect in HeLa cells. When cells were treated with $0{\sim}50{\mu}M$ of RSV for 24 hr, the expression of ANG and VEGF was significantly increased in a dose dependent manner measured by real-time PCR. Similarly, we performed time dependent experiments for $50{\mu}M$ RSV treated cells and identified the optimized time at 24 hr. The increased expression in RSV treated cells was confirmed by Western blot analysis. To examine the toxic effects of RSV at the determined conditions, MTT assays were performed. The viabilities were unchanged for $0{\sim}50{\mu}M$ RSV treated cells, while they decreased at $100{\mu}M$ RSV. To examine the effect of migration in RSV treated cells, we performed a wound-healing assay. The migratory rates were significantly enhanced in the RSV treated group. In this study, we found that RSV induces an increase in the expression of migration factors ANG, VEGF, and enhances cell migration for the determined conditions.

• International Journal of Naval Architecture and Ocean Engineering
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• v.5 no.4
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• pp.529-545
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• 2013

Strong restrictions on emissions from marine power plants (particularly $SO_x$, $NO_x$) will probably be adopted in the near future. In this paper, a combined solid oxide fuel cell (SOFC) and gas turbine fuelled by natural gas is proposed as an attractive option to limit the environmental impact of the marine sector. It includes a study of a heat-recovery system for 18 MW SOFC fuelled by natural gas, to provide the electric power demand onboard commercial vessels. Feasible heat-recovery systems are investigated, taking into account different operating conditions of the combined system. Two types of SOFC are considered, tubular and planar SOFCs, operated with either natural gas or hydrogen fuels. This paper includes a detailed thermodynamic analysis for the combined system. Mass and energy balances are performed, not only for the whole plant but also for each individual component, in order to evaluate the thermal efficiency of the combined cycle. In addition, the effect of using natural gas as a fuel on the fuel cell voltage and performance is investigated. It is found that a high overall efficiency approaching 70% may be achieved with an optimum configuration using SOFC system under pressure. The hybrid system would also reduce emissions, fuel consumption, and improve the total system efficiency.

• Transactions of the Korean hydrogen and new energy society
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• v.18 no.2
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• pp.151-156
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• 2007

Solar cell and nanofiltration membrane were utilized in a system of enzymatic hydrogen production through light-sensitized photoanode, which resembles photoelectrochemical(PEC) configuration. Solar cell uses no additional light energy to increase energy for electrons to reduce protons and for holes to oxidize water to oxygen, and nanofiltration membrane replaces a salt bridge successfully with increased ion transport capability. With this system configuration, optimized amount of enzyme(10.98 unit), and an anodized tubular $TiO_2$ electrode($5^{\circ}C$/1 hr in 0.5 wt% HF-$650^{\circ}C$/5 hr) hydrogen evolved at a rate of ca. $43\;{\mu}mol/(cm^2{\times}hr)$ in a cathodic compartment and oxygen generated at a rate of ca. $20\;{\mu}mol/(cm^2{\times}hr)$ in an anodic compartment. The stoichiometric evolution of gases indicated that water was splitted in the system.

• Korean Journal of Veterinary Research
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• v.51 no.2
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• pp.171-175
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• 2011

Malignant Sertoli cell tumor was diagnosed in a 5-year-old male Shih Tzu dog. Clinical features of the dog were anorexia, urinary incontinence, constipation, anemia, alopecia, and epistaxis. The dog also had unilateral cryptorchid testis in the abdomen. Several abdominal and thoracic masses were identified on radiography. Grossly, the cryptorchid testicular mass was markedly enlarged to 8 cm in diameter. On cut surface, firm and well demarcated milk-white neoplastic areas were irregularly separated by white fibrous bands. Histologically, the testicular mass was diagnosed as tubular pattern Sertoli cell tumor. In addition, abdominal and mediastinal lymph nodes metastasis were found. Immunohistochemically, the tumor cells were strongly positive for vimentin and neuron specific enolase, but negative for S-100 and cytokeratin.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.45-47
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• 2002

Although Dacron and ePTFE have most widely been used for artificial vascular grafts, these materials cannot be used for small-diameter grafts (l.D.<6mm) due to thrombotic occlusion. To overcome this limitation, a small-diameter vascular graft was developed with stem cell and tissue engineering method. Autologous bone marrow stem cells were cultured and seeded onto small-diameter (4mm) collagen tubular matrices. The matrices were anastomosed to carotid arteries in canine models. Prior to implantation, histological and electron microscopical examination revealed stem cell adhesion and growth on the matrices. Angiography indicated that the vascular grafts maintained patent for 8 weeks. Histological examination showed the regeneration of endothelium, media and adventitia in the grafts. This study may allow us to step forward to the development of tissue-engineered small-diameter vascular graft appropriate for clinical applications.

• Korean Journal of Veterinary Research
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• v.36 no.3
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• pp.521-529
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• 1996

In an effort to obtain basic data of carbohydrate metabolism during spermiogenesis of the sexually-matured Jindo dog, the glycogen distribution in the testis was investigated by light and transmission electron microscopy. Periodic acid thiocarbohydrazide silver proteinate physical development(PA-TCH-SP-PD) staining method provided better results in the detection of glycogen granules from Sertoli cells and germ cells than the periodic acid schiff(PAS) staining method did. Pre-treatment of the tissue sections with ${\alpha}$-amylase elicited a significant decrease in PA-TCH-SP-PD stained granules, which suggested that the stained granules were of glycogen origin. High concentration of the glycogen granules were observed in the Sertoli cells, especially in its column, sheet-like processes, club-like processes, and tubular processes. The glycogen granules were unevenly distributed in some Sertoli cell columns. These results strongly indicated that the Sertoli cells of Jindo dogs showed vigorous activity of carbohydrate metabolism.

• Korean Journal of Bronchoesophagology
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• v.6 no.1
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• pp.108-112
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• 2000

Epithelial-myoepithelial carcinoma(EMC) is a rare low grade malignant salivary gland neoplasm that most commonly occurs in the parotid gland but can also arise in minor salivary glands. It is a distinct neoplasm characterized by tubular and solid growth patterns and a dual cell population including an inner larger of cuboidal to columnar epithelial cells which are peripherally bounded by a layer of myoepithelial cells with distinctly clear cytoplasm. The clinical course is characterized by a high incidence of local recurrence and not infrequent distant metastasis. The differential diagnosis included acinic cell tumor, adenoid cystic carcinoma, mucoepidermoid carcinoma, sebaceous carcinoma and pleomorphic adenoma. We report a case of EMC of left parotid gland in a 55-year-old woman.