• Korean Journal of Veterinary Research
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• v.38 no.2
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• pp.280-289
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• 1998

Voltage-sensitive ion channels contribute to establishment of the cell excitablity and the generation of the cellular function. At hamster oocytes in the primitive stage during developing process, an inward current elicited by voltage pulses was found to be carried mainly by $Ca^{2+}$. Even at present, $Ca^{2+}$ channels serve as the most probable route to pass this inward current but there is no evidence of the presence of this channels in eggs. To date, both the characteristic properties and the physiological role in the early stage of development remain unclear. Here we examined the characteristic properties of the inward current and changes in this currents at unfertilized oocytes, fertilized zygotes and two-cell embryos using whole-cell voltage clamp technique. The inward current carried reportedly by $Ca^{2+}$ was remained following removing external $Ca^{2+}$ but completely abolished by further replacement of impermeants such as tetramethylammonium ion ($TMA^+$) or $choline^+$ instead of $[Na^+]_0$. Tetrodotoxin did not affect on this inward current remained at $[Ca^{2+}]_0$-free condition. Removal of $Na^+$ ion out of the experimental solution clearly decreased the current. After adding 2mM $Ca^{2+}$ to the $Na^+$-free media, the inward current was restored. Interestingly, this current carried by either $Ca^{2+}$ or $Na^+$ was decreased by the reduction of intracellular $Cl^-$ concentration, or by $Cl^-$ channel blockers such as niflumic acid, DIDS and SITS. When $Cl^-$ concentration was lowered without changes in other ionic components, this inward current was reduced. At fertilized oocytes and two-cell embryos, the inward current carried by $Ca^{2+}$ and $Na^+$ was severely reduced. Also $Cl^-$ component could not be observed. From these results, the inward current is composed of $Ca^{2+}$, $Na^+$ and $Cl^-$ component, suggesting that the channel carrying this inward current is not selective specifically to $Ca^{2+}$. During early stage of development, the voltage-sensitive ion current seems not to contribute essentially to the cell cleavage and differentiation. The loss of $Cl^-$ component after fertilization suggests that $Cl^-$ may play a role in maintaining the viability of unfertilized ova.

• Membrane Journal
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• v.24 no.1
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• pp.69-77
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• 2014

To prepare the hollow fiber nanofiltration composite membranes, the poly(vinylidene fluoride) (PVDF) membrane was hydrophilized with $K_2Cr_2OH$ and $KMnO_4$ aqueous solutions. And then the composite membrane was synthesized on that membrane surfaces using interfacial polymerization with piperazine (PIP) and trimesoyl chloride (TMC). The resulting membranes were characterized in terms of the rejection and flux for NaCl, $CaSO_4$, $MgCl_2$ 100 ppm solution and 300 ppm of NaCl and $CaSO_4$ mixed solution by varying the coating time, drying time, and the concentration of the coating materials. As a result, the higher rejections were shown for $K_2Cr_2OH$ solutionas a hydrophilization material, and the flux was enhanced while the rejection reduced as the hydrophilization time is longer. Also, the rejection increased and the flux reduced as the concentrations of triethyl amine (TEA) and sodium lauryl sulfate (SLS) were higher. Typically, the rejection 50% and flux 40 LMH for NaCl 100 ppm solution, and the rejection 55% and flux 48 LMH for $CaSO_4$ 100 ppm solution were obtained for the PVDF hollow fiber composite membrane prepared with the conditions of PIP 2 wt% (Triethyl amine (TEA) 7 wt%, SLS 20 wt% mixed solution against PIP concentration) and TMC 0.1 wt%.

• Korean Journal of Food Science and Technology
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• v.44 no.4
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• pp.488-492
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• 2012

Two strains, traditionally referred to as rock flower (Bawhi-kot) and buckwheat flower (Memil-kot or Chile-Kot), were isolated from stored traditional soy sauce and were identified by using the 18S ITS1/4 region sequences. The rock flower strain showed 99% of similarity with Cladosporium sp. and buckwheat flower strain was 99% identical with yeast Sterigmatomyces halophilus. Both strains were tentatively named Cladosporium sp. NK1 and Sterigmatomyces halophilus NK2, respectively. The optimal growth pHs and temperatures of both strains in a YPD broth medium were in the range of pH 5.0 to 7.0 and 22 to $27^{\circ}C$. Both strains were able to grow in more than 20% of NaCl. In the enzyme activity assay, high protease activity of Cladosporium sp. NK1 and S. halophilus NK2 were obtained in YPD containing 10% of NaCl. High amylase activities of both stains were in 15% and 5% of NaCl, respectively. Lipase activity was, however, not detected in both strains.

• Journal of Korea Soil Environment Society
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• v.3 no.1
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• pp.65-74
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• 1998

To enhance the washing efficiency of soil polluted by hydrophobic organic compounds, the effects of electrolytes and monomeric organic additives on micelle formation and washing efficiency of mixed surfactant solutions were investigated in this study. The surface tensions and critical micelle concentrations(CMCs) of the single and mixed surfactant solutions[$POE_5$/SDS] supplemented by NaCl were measured to investigate the effects on washing efficiency, and the composition ratios of surfactants and NaCl were optimized for the efficient soil washing system. As the mixing ratio of $POE_5$/SDS was increased to 80%, the mixed surfactant with 0.01M NaCl showed more proportional increase of washing efficiency than the mixed surfactant without any salts. The 3% solution of $POE_5$ and SDS(80%/2o%) with 0.01M NaCl showed the washing efficiency of 90%. However, the washing efficiency was not enhanced by NaCl addition to the single surfactant solution of $POE_5$. The CMC of SDS(0.049%) was higher than that of $POE_5$(0.016%), but the CMCs of mixed surfactants were decreased as the mixing ratio of $POE_5$ was increased. Alcohols having longer chain and branched carbon chain were found to be desirable for the soil washing additives.

• Corrosion Science and Technology
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• v.17 no.3
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• pp.116-122
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• 2018

The secondary coolant of a nuclear power plant has small amounts of various impurities (S, Pb, and Cl, etc.) introduced during the initial construction, maintenance, and normal operation. While the concentration of impurities in the feed water is very low, the flow of the cooling water is restricted, so impurities can accumulate on the Top of Tubesheet (TTS). This environment is chemically very complicated and has a very wide range of pH from acidic to alkaline. In this study, the characteristics of the oxide and the mechanism of stress corrosion cracking (SCC) are investigated for Alloy 690 TT in alkaline solution containing Pb, Cl, and S. Reverse U-bend (RUB) specimens were used to evaluate the SCC resistance. The test solution comprises 3m NaCl + 500ppm Pb + 0.31m $Na_2SO_4$ + 0.45m NaOH. Experimental results show that Alloy 690 TT of the crevice environment containing Pb, S, and Cl has significant cracks, indicating that Alloy 690 is vulnerable to stress corrosion cracking under this environment.

• Journal of Pharmacopuncture
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• v.4 no.2
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• pp.49-56
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• 2001

This study was undertaken to determine whether Scutellaria baicalensis Georgi (SbG) extract exerts the protective effect against $HgCl_2$-induced alterations in membrane transport function in rabbit renal cortical slices. The slices were treated with 0.1 mM $HgCl_2$ for 60 min at $37^{\circ}C$. $HgCl_2$ caused an inhibition in PAH uptake by renal cortical slices. Such an effect was accompanied by depressed $Na^+-K^+$-ATPase activity and ATP depletion. SbG prevented $HgCl_2$-induced inhibition of PAH uptake in a dose-dependent manner at the concentration ranges of 0.01-0.1%. $HgCl_2$-induced inhibition of $Na^+-K^+$-ATPase activity and ATP depletion were significantly prevented by 0.05% SbG. These results suggest that SbG prevents $HgCl_2$-induced alterations in membrane transport function in rabbit renal cortical slices. Such protective effects of SbG may be attributed to inhibition of peroxidation of membrane lipid.

• The Korean Journal of Mycology
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• v.36 no.1
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• pp.75-83
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• 2008

Lentinus giganteus, one of edible and medicinal mushroom belongs to Pleurotaceae of Agaricales, has been known to contain some inhibitive substances on Sarcoma 180 and curative effect on high blood pressure. Neutral saline soluble (0.9% NaCl), hot water soluble and methanol soluble substances (hereinafter referred to Fr. NaCl, Fr. HW and Fr. MeOH, respectively) were extracted from fruiting body of the mushroom. In vitro cytotoxicity tests, crude polysaccharides were not cytotoxic against cancer cell lines such as Sarcoma 180 and HepG2 at the concentration of $10{\sim}2,000\;{\mu}g/ml$, but crude polysaccharides from Fr. NaCl was toxic to NIH3T3 at the concentration of $10{\sim}2,000\;{\mu}g/ml$. Intraperitoneal injection with crude polysaccharides showed life prolongation effect of $14.3{\sim}67.5%$ in mice previously inoculated with Sarcoma 180, respectively. Fr. NaCl exhibited the immuno-potentiating activity of B lymphocyte by increasing the alkaline phosphatase activity by $1.53{\sim}1.68$ folds compared with control at the concentration of $50{\sim}200\;{\mu}g/ml$, respectively. The numbers of peritoneal exudate cells and circulating leukocytes were increased by 7.7 and 1.6 folds by injecting Fr. NaCl and Fr. MeOH into the mice at the concentration of 50 mg/ml body weight, respectively.

• The Korean Journal of Pharmacology
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• v.27 no.1
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• pp.33-43
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• 1991

To study the age dependent change of Na, K-ATPase in the erythrocyte of hypertensive rat, 1-kidey 1-clip hypertensive rat was made by the removal of right kidney and partial ligation of left renal artery. After 4 weeks, aged erythrocyte fraction was separated by density gradient centrifugation, and Na, K-ATPase activity and $^3H-ouabain$ binding with ghost cell membrane and ouabain sensitive Rb-uptake with whole cell were measured. 1) In the hypertensive rats, blood pressure was significantly increased to 165.5/119.0 mmHg (systolic/diastolic). Mean corpuscular volume and membrane protein(mg) per $10^9RBC$ were decreased and hemoglobin content was increased in the aged erythrocyte. 2) Na, K-ATPase activity in the solution containing 110 mM NaCl and 10 mM KCI, was decreased in hypertensive rat, and decreased in aged erythrocyte of both group. 3) Ouabain sensitive Rb-uptake by low RbCl concentration(4 mM) was slightly decreased in aged erythrocyte compared to that in young erythrocyte of each group, but slightly increased in young erythrocyte in hypertensive rat compared to that in normotensive rat. 4) Ouabain sensitive Rb-uptake by high RbCl concentration(16 mM) was decreased about 30% to 50 % in aged erythrocyte in both group. And in hypertensive rat, especially in young erythrocyte it was significantly decreased compared to that in normotensive rats. 5) $^3H-ouabain$ binding at 0.13 or $1{\times}10^-6M$ ouabain concentration was slightly decreased in aged erythrocyte of normotensive rat, and significantly decreased in aged erythrocyte of hypertensive rats. 6) $^3H-ouabain$ binding at 6 or $64{\times}10^-6M$ ouabain concentration is slightly decreased in aged erythrocyte of both group, but significantly decreased in young and aged erythrocyte of hypertensive rats compared to that of normotensive rats. The present results suggest that (1) in the young erythrocyte of hypertensive rat, the alterations of Na-pump activity that slightly increased in weak stimulation and inhibited in strong stimulation, may be related to increased molecular activity and the decrease in the number of low affinity site without change in high affinity site, (2) in the aged erythrocyte of normotensive rat, inhibited Na-pump may be related to the change in molecular activity of pump. (3) And in the aged erythrocyte of hypertensive rat, it may be related to the decrease in the number of high and low affinity site as well as the change in molecular activity

• Journal of Korean Society for Atmospheric Environment
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• v.22 no.E2
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• pp.78-88
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• 2006

In order to study the characteristics of cloud, a real-scale experiment for cloud generation was carried out using an extinct vertical mine (430 m height) located in the northeastern Honshu, Japan. The dry particles generated from the three-step concentrations of NaCl solutions were used for cloud generation. The number size distributions of initial dry particles and cloud droplets were monitored by Scanning Mobility Particle Sizer (SMPS) and Forward Scattering Spectrometer Probe (FSSP) at bottom and upper sites of pit, respectively. The polymeric water absorbent film (PWAF) method was employed to measure liquid water content ($W_L$) as a function of droplet size. Moreover the chemical properties of individual droplet replicas were determined by micro-PIXE. The CCN number concentration shows the lognormal form in dependence of the particle size, while the number size distributions of droplets are bimodal showing the peaks around $9{\mu}m$ and $20{\mu}m$ for every case. In comparison to background mineral particles, right shifting of size distribution line for NaCl particles was occurred. When NaCl solutions with three-step different concentrations were neulized, $W_L$ shows the strong droplet size dependence. It varied from $10.0mg\;m^{-3}$ up to $13.6mg\;m^{-3}$ with average $11.6mg\;m^{-3}$. A good relationship between $W_L$ and cloud droplet number concentration was obtained. Both chemical inhomogeneities (mixed components with mineral and C1) and homogeneities (only mineral components or C1) in individual droplet replicas were obviously observed from micro-PIXE elemental images.

• The Korean Journal of Physiology and Pharmacology
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• v.8 no.5
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• pp.259-264
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• 2004

Cytolysin produced by Vibrio vulnificus has been incriminated as one of the important virulence determinants in V. vulnificus infection. Ion selectivity of cytolysin-induced pores was examined in a CPAE cell, a cell line of pulmonary endothelial cell, using inside-out patch clamp techniques. In symmetrical NaCl concentration (140 mM), intracellular or extracellular application of cytolysin formed ion-permeable pores with a single channel conductance of $37.5{\pm}4.0$ pS. The pore currents were consistently maintained after washout of cytolysin. Replacement of $Na^+$ in bath solution with monovalent ions $(K^+,\;Cs^+\;or\;TEA^+)$ or with divalent ions $(Mg^{2+},\;Ca^{2+})$ did not affect the pore currents. When the NaCl concentration in bath solution was lowered from 140 to 60 and 20 mM, the reversal potential shifted from 0 to -11.8 and -28.2 mV, respectively. The relative permeability of the cytolysin pores to anions measured at $-40\;mV\;was\;Cl^-\;=\;NO_2^-\;{\geq}\;Br^-\;=\;I^-\;> \;SCN^-\;>\;acetate^-\;>\;isethionate^-\;>\;ascorbic acid^-\;>\;EDTA^{2-},$ in descending order. The cytolysin-induced pore current was blocked by $CI^-$ channel blockers or nucleotides. These results indicate that V. vulnificus cytolysin forms anion-selective pores in CPAE cells.