• The Korean Journal of Physiology and Pharmacology
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• v.3 no.6
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• pp.623-630
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• 1999

Decreased cardiac contractility occurs in endotoxicosis, but little is known about the ionic mechanism responsible for myocardial dysfunction. In this study, we examined the changes in $Ca{2+}$ and $K^+$ currents in cardiac myocytes from endotoxin-treated rat. Ventricular myocytes were isolated from normal and endotoxemic rats (ex vivo), that were treated for 10 hours with Salmonella enteritidis lipopolysaccharides (LPS; 1.5 mg/kg) intravenously. Normal cardiac myocytes were also incubated for 6 hours with 200 ng/ml LPS (in vitro). L-type $Ca{2+}$ current $(I_{Ca,L})$ and transient outward $K^+$ current $(I_{to})$ were measured using whole cell patch clamp techniques. Peak $I_{Ca,L}$ was reduced in endotoxemic myocytes (ex vivo; 6.00.4 pA/pF, P＜0.01) compared to normal myocytes (control; 10.90.6 pA/pF). Exposure to endotoxin in vitro also attenuated $I_{Ca,L}$ (8.40.4 pA/pF, P＜0.01). The amplitude of $(I_{to})$ on depolarization to 60 mV was reduced in endotoxin treated myocytes (16.51.5 pA/pF, P＜0.01, ex vivo; 20.00.9 pA/pF, P＜0.01 , in vitro) compared to normal myocytes (control; 24.71.0 pA/pF). There was no voltage shift in steady-state inactivation of $I_{Ca,L}$ and $(I_{to})$ between groups. These results suggest that endotoxin reduces $Ca{2+}$ and $K^+$ currents of rat cardiac myocytes, which may lead to cardiac dysfunction.

• The Journal of Korean Medicine
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• v.27 no.2 s.66
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• pp.171-181
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• 2006

Objectives : Peroxynitrite($ONOO^-$), superoxide anion(${\cdot}{O_2}^-$) and nitric oxide (NO) is a cytotoxic species that can oxidize several cellular components such as proteins, lipids and DNA. It has been implicated in the aging process and age-related disease such as Alzheimer's disease, rheumatoid arthritis, cancer and atherosclerosis. The aim of this study was to investigate scavenging activities for $ONOO^-$ and its precursors, NO and ${\cdot}{O_2}^-$ of Vespae Nidus. Methods : Dichlorodihydrofluorescein diacetate (DCFDA), 4,5-diaminofluorescein (DAF-2) and dihydrorhodamine 123 (DHR 123) were used to investigate scavenging activities of $ONOO^-,\;NO,\;{\cdot}{O_2}^-$. Six-months-old ICR mice were used. After mice were injected with lipopolysaccharides(LPS), kidney organization was evaluated. Three comparison groups of ICR mice were used : a normal group, an experimental group that was fed Vespae Nidus extract and then injected with LPS, and a control group that was injected with LPS. Scavenging activities of $ONOO^-,\;NO,\;{\cdot}{O_2}^-$ in these groups were measured in the same way. Results : Vespae Nidus markedly scavenged authentic $ONOO^-,\;{\cdot}{O_2}^-$ and NO. It also inhibited $ONOO^-$ induced by ${\cdot}{O_2}^-$ and NO which are derived trom SIN-1. Furthermore, it inhibited $ONOO^-,\;{\cdot}{O_2}^-$, and NO generation by Vespae Nidus in LPS-treated ICR mouse kidney postmitochondria. Conclusions : These results suggest that Vespae Nidus might be developed as an effective $ONOO^-,\;{\cdot}{O_2}^-$, and NO scavenger for the prevention of the aging process and age-related diseases.

• Clinical and Experimental Pediatrics
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• v.61 no.2
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• pp.64-67
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• 2018

We report the case of a 12-year-old girl who had mild encephalopathy with a reversible splenial lesion (MERS) associated with acutepyelonephritis caused by Escherichia coli. The patient was admitted with a high fever, and she was diagnosed with acute pyelonephritis based on pyuria and the results of urine culture, which detected cefotaxime-sensitive E. coli. Although intravenous cefotaxime and tobramycin were administered, her fever persisted and her C-reactive protein level increased to 307 mg/L. On day 3 of admission, she demonstrated abnormal neuropsychiatric symptoms, such as delirium, ataxia, and word salad. Magnetic resonance imaging (MRI) of the brain performed on day 4 showed marked hyperintensities in the bilateral corpus callosum and deep white matter on diffusion-weighted images, with corresponding diffusion restriction on apparent diffusion coefficient mapping. No abnormalities or pathogens were detected in the cerebrospinal fluid; however, lipopolysaccharides (LPS, endotoxin) were detected in plasma (41.6 pg/mL), associated with acute neurological deterioration. Her clinical condition gradually improved, and no neurological abnormalities were observed on day 6. Follow-up brain MRI performed 2 weeks later showed near-disappearance of the previously noted hyperintense lesions. In this patient, we first proved endotoxemia in a setting of MERS. The release of LPS following antibiotic administration might be related to the development of MERS in this patient. The possibility of MERS should be considered in patients who present with acute pyelonephritis and demonstrate delirious behavior.

• Microbiology and Biotechnology Letters
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• v.41 no.2
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• pp.242-248
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• 2013

Endotoxins are part of the outer membrane of the cell wall of gram-negative bacteria and are continuously released during bacterial growth. Endotoxins typically induce severe sepsis and septic shock, which cause more than 50% of mortalities. Endotoxins are easily measured in the serum by the limulus amebocyte lysate (LAL) test. However, a nonspecific result is obtained, because the high concentration of serum proteins disturbs the enzyme reaction of the LAL test. In order to solve this problem, the LAL test was performed in this study after the centrifugation of the boiled serum samples to remove the impurities. As a result, among the various conditions examined, endotoxin measurement with the LAL test was the most accurate and repeatable after centrifugation of the boiled serum at $100^{\circ}C$. Moreover, the endotoxin was accurately and repeatedly measured from the prepared sera of mice that had been administered an intraperitoneal injection of purified lipopolysaccharides (LPS) or E. coli. Therefore, the application of centrifugation to remove impurities from boiled serum gives an accurate measurement of endotoxins in the sera of normal subjects or patients, and this will lead to the improved diagnosis and prevention of diseases caused by endotoxins. In addition, the centrifugation of boiled serum samples should be considered and included in the development of endotoxin test kits.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.4
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• pp.384-392
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• 2013

An ethanolic extract of Undaria pinnatifida was fractionated using several solvents. Of the fractions, the ethyl acetate fraction had the greatest inhibitory effect on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW 264.7 macrophage cells. Using this fraction (U. pinnatifida ethyl acetate extract, UPE), we investigated the molecular mechanism underlying its inhibitory effect on LPS-stimulated RAW 264.7 cells. Pretreatment of the cells with up to $100{\mu}g/mL$ UPE significantly inhibited NO production and inducible nitric oxide synthase (iNOS) expression, in a dose-dependent manner. Similarly, UPE treatment markedly reduced the production of pro-inflammatory cytokines, such as interleukin (IL)-1, IL-6 and tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), while it strongly suppressed the nuclear translocation of nuclear factor-kappa B (NF-${\kappa}B$) by preventing proteolytic degradation of inhibitor of nuclear factor ${\kappa}B$ $(I{\kappa}B)-{\alpha}$. Moreover, UPE treatment significantly reduced the phosphorylation of phosphatidylinositol 3-kinase (PI3K)/Akt and mitogen-activated protein kinase (MAPK) in LPS-stimulated cells. These results indicate that UPE contains anti-inflammatory compounds and suggest that it might be used as a functional food material that assists in prevention of inflammatory diseases.

• The Korea Journal of Herbology
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• v.31 no.1
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• pp.61-67
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• 2016

Objectives : The present study aimed to investigate the anti-inflammatory effects of the water extracts of Portulacae Herba (PH).Methods : We measured the effects of the water extracts of Portulacae Herba (PH) on the cell viability of mouse macrophage RAW 264.7 cells, the intracellular calcium production, and the proinflammatory mediators including nitric oxide (NO), vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF)-BB, which are induced by the lipopolysaccharides (LPS), and obtained the results shown below.Results : After the cultivation of the PH extracts along with the mouse macrophages, the cell survival rate did not decrease with the MTT assay. However, the PH extracts did significantly suppress the production of NO by the mouse macrophages induced by LPS at the concentrations of 25, 50 and 100 ㎍/mL. The PH extract also significantly suppressed the VEGF, PDGF-BB and intracellular calcium production of the mouse macrophages by LPS at concentrations of 25, 50 and 100 ㎍/mL. As shown in the results above, the PH extracts do not have a toxic effect on the macrophages, but still have an anti-inflammatory effect that significantly reduces the intracellular calcium production as well as the production of NO, VEGF and PDGF-BB at concentrations above 25 ㎍/mL.Conclusions : In conclusion, the inhibitory anti-inflammatory effects of the PH extract can be used for a new treatment of anti-inflammatory diseases.

• Tuberculosis and Respiratory Diseases
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• v.69 no.5
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• pp.337-347
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• 2010

Background: Transglutaminase-2 (TG-2) has been reported to play an important role in the process of fibrosis. However, TG-2 studies on fibroproliferation of acute lung injury (ALI) are absent. The purpose of this study was to investigate the role of TG-2 in the fibroproliferation of lipopolysaccharide (LPS)-induced ALI. Methods: The male C57BL/6 mice of 5 weeks age were divided into 3 groups; control group (n=30) in which $50{\mu}L$ of saline was given intratracheally (IT), LPS group (n=30) in which LPS 0.5 mg/kg/$50{\mu}L$ of saline was given IT, and LPS+Cyst group treated with intraperitoneal 200 mg/kg of cystamine, competitive inhibitor of TG-2, after induction of ALI by LPS. TG-2 activity and nuclear factor $(NF)-{\kappa}B$ were measured in lung tissue homogenate. Tumor necrosis factor (TNF)-${\alpha}$, interleukin (IL)-$1{\beta}$, IL-6, myeloperoxidase (MPO), and transforming growth factor (TGF)-${\beta}1$ were measured using bronchoalveolar lavage fluids. Histopathologic ALI score and Mallory's phosphotunistic acid hematoxylin (PTAH) for collagen and fibronectin deposition were performed. Results: The TG-2 activities in the LPS group were significantly higher than the control and LPS+Cyst groups (p<0.05). The TNF-${\alpha}$ and IL-$1{\beta}$ concentrations and $NF-{\kappa}B$ activity were lower in the LPS+Cyst group than the LPS group (p<0.05). The LPS+Cyst group showed lower MPO, ALI score, TGF-${\beta}1$ concentration, and Mallory's PTAH stain than the LPS group, but the differences were not significant (p>0.05). Conclusion: Inhibition of TG-2 activity in the LPS-induced ALI prevented early inflammatory parameters, but had limited effects on late ALI and fibroproliferative parameters.

• KSBB Journal
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• v.31 no.4
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• pp.228-236
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• 2016

The aim of this study was to characterize the hemolytic Aeromonas sp. MH-8 exposed to green tea catechin, epigallocatechin gallate (EGCG). Initially, the hemolytic Aeromonas sp. MH-8 was enriched and isolated from stale fish. Bactericidal effects of MH-8 exposed to EGCG ranging from 1 mg/mL to 4 mg/mL were monitored, and complete bactericidal effects were achieved within 3 h at 3 mg/mL and higher concentrations. SDS-PAGE with silver staining revealed that the amount of lipopolysaccharides increased or decreased in the strain MH-8 treated to different concentrations and exposing periods of EGCG in exponentially growing cultures. The stress shock proteins (70-kDa DnaK and 60-kDa GroEL), which might contribute to enhancing the cellular resistance to the cytotoxic effect of EGCG, were induced at different concentrations of EGCG exposed to cell culture of MH-8. Scanning electron microscopic analysis demonstrated the presence of irregular rod shapes with umbilicated surfaces for cells treated with EGCG. 2-DE of soluble protein fractions from MH-8 cultures showed 18 protein spots changed by EGCG exposure. These proteins involved in chaperons (e.g., DnaK, GroEL and trigger factor), enterotoxins (e.g., aerolysin and phospholipase C precursor), LPS synthesis (e.g., LPS biosynthesis protein and outer membrane protein A precursor), and various biosynthesis and energy metabolism were identified by peptide mass fingerprinting using MALDI-TOF. In consequence, EGCG was found to have substantial antibacterial effects against food-poisoning causing bacterium, hemolytic Aeromonas sp. MH-8. Also the results provide clues for understanding the mechanism of EGCG-induced stress and cytotoxicity on Aeromonas sp. MH-8.

• Journal of Periodontal and Implant Science
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• v.40 no.6
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• pp.257-264
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• 2010

Purpose: Connective tissue reattachment to periodontally damaged root surfaces is one of the most important goals of periodontal therapy. The aim of this study was to develop a root conditioning agent that can demineralize and detoxify the infected root surface. Methods: Dentin slices obtained from human teeth were treated with a novel root planing agent for 2 minutes and then washed with phosphate-buffered saline. Smear layer removal and type I collagen exposure were observed by scanning electron microscopy (SEM) and type I collagen immunostaining, respectively. Cell attachment and lipopolysaccharides (LPS) removal demonstrated the efficiency of the root conditioning agent. Results: SEM revealed that the smear layer was entirely removed and the dentinal tubules were opened by the experimental gel. Type I collagen was exposed on the surfaces of the dentin slices treated by the experimental gel, which were compared with dentin treated with other root planing agents. Dentin slices treated with the experimental gel showed the highest number of attached fibroblasts and flattened cell morphology. The agar diffusion assay demonstrated that the experimental gel also has effective antimicrobial activity. Escherichia coli LPS were effectively removed from well plates by the experimental gel. Conclusions: These results demonstrated that this experimental gel is a useful tool for root conditioning of infected root surfaces and can also be applied for detoxification of ailing implant surface threads.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.2
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• pp.180-185
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• 1999

Effects of host immunization on bacterial translocation and growth performance in weanling piglets were studied. Twenty four barrows were assigned to one of two immunization treatments: Control group (CON: immunized with placebo) or Immunization group [IMMU: immunized with Antigen cocktail; Keyhole limpet hemocyanin (KLH), Ovalbumin (OA), and Tetanus toxoid (TT)]. On d0, piglets were weaned and intramuscularly immunized with 2 ml of placebo or Antigen cocktail, respectively. Antigen-specific Ig titers were determined by ELISA (Enzyme Linked ImmunoSorbent Assay). Ig titers to E. coli-derived lipopolysaccharides (LPS) were measured as the indicator of bacterial translocation. Ig titers to LPS were higher (p<0.10, 0.05 or 0.01) in CON group before immunization (d0), but the difference disappeared with time and IgA titers to LPS became higher (p<0.05) in IMMU group on d39. In IMMU group, IgG titers to LPS from d28 onwards showed positive correlations (p<0.10, 0.05, 0.01 or 0.001) with IgG titers to KLH from d11 onwards and with IgM titers to KLH from d7 onwards. Generally, growth performance was negatively related to IgG titers to LPS. Average daily gain for d28 to d35 showed negative correlations (p<0.10, 0.05, or 0.01) with IgG titers to LPS on d28 onwards in immunization group. These results reveal some evidences that host immunization might facilitate bacterial translocation and high humoral immune responses to LPS are negatively related with the growth performance.