• Journal of The Korean Society of Grassland and Forage Science
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• v.20 no.4
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• pp.265-274
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• 2000

To investigate the effects of anion replacement on NO3- concentration in Italian ryegrass. Plants weregrown hydroponically to the full vegetative stage. NO3 supply(control) was replaced with SO1- (Tl), C1-(T2) and water (T3) to during 14 days. The determination of inorganic nutrient uptake and quantification ofprincipal metabolites (nitrate. protein and sugar) followed. Relatively high uptake of ~ a a'n d Ca" for controlplants, K+ and POJ- for T2 plants, and C 1 for TI plants was observed, respectively. Proteins in shoot andstubble were relatively higher in control and TI plants, which coupled N source. In root proteins largelydecreased (especially in T3 plants) during experimental period. Sugars in shoot of all four treatments tendedto decrease during the first 7 days and recovered afterward. Sugars in stubble also markedly decreased duringthe first 7 days, while those in root was much less varied during experimental period. After 14 days oftreatment, nitrate concentration in shoot of control plants was 13mgIg FW. Comparing to control: nitrate inshoot reduced by 27%, 46% and 50% in TI, T2 and T3 plants, respectively. Dry weight was slightlyincreased or not significantly changed in control, T1 and T2 plants, while a significant decrease(31.3% ofcontrol) occurred in T3 plants.(Key words : Italian ryegrass, Anion replacement, Ion uptake, Protein, Sugar, Nitrate)ptake, Protein, Sugar, Nitrate)

• 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.

• Journal of the Korean Chemical Society
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• v.38 no.2
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• pp.122-128
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• 1994

Macrocyclic ligand has been known to selectively bind with metal ions so that ability applied for the transport of metal ions across the emulsion liquid membrane in this study. The metal ions are transproted from the source phase to the receiving phase by the carrier of the organic phase. Several factors involved in the transport of metal ions acrose the emulsion membrane we reported here and these factors provided the informations for the selective seperation of some metal ion. Stability constants for cation-macrocyclic ligand and metal ion-anion receiving phase interaction are examined as parameters for the prediction of metal ion transport selectivities. $Pb^{2+}$ was transported higher rates than the other metal ions in the mixture solution. The interaction of metal ion to anion in receiving phase is important. $S_2O_3^{2-}$- in replacement of $NO_3^-$ in the receiving phase enhances the transport of $Pb^{2-}$since $Pb^{2-}-S_2O_3^{2-}$interaction is greater than $Pb^{2+}-NO_3^-$ interaction.

• Bulletin of the Korean Chemical Society
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• v.23 no.12
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• pp.1754-1758
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• 2002

Tetrathiafulvalene(TTF) reacts with $PdCl_2,Pd(NO_3)_2$ and $Pd(hfacac)_2$(hexafluoroacetylacetonate) in ethanol to give $(TTF)_{1.5}PdCl_2$ (1a), $(TTF)_3Pd(NO_3)_2$ (1b) and $(TTF)_4Pd(hfacas)_2$ nd (1c), respectively. $PdCl(TCNQ)_{2.5}{\cdot}CH_3OH(2a)$was obtained from the reaction of $PdCl_2$ with LiTCNQ in methanol via the partial replacement of $Cl^-$ in $PdCl_2$ by $TCNQ^-$anion, whereas the total substitution of the labile $NO_3^-$ in $Pd(NO_3)_2$ yielded pd(TCNQ)·$CH_3OH$ (2b). $Pd(hfacac)_2(TCNQ)_2\cdot3CH_3OH$ (2c) was obtained from $Pd(hfacac)_2$ and LiTCNQ in methanol. The prepared compounds were characterized by spectroscopic (IR, UV, XPS) methods and magnetic (EPR, magnetic susceptibility) studies. The powdered electrical conductivities (${\sigma}_{rt}$) of the prepared compounds at room temperature were about~$10^{-7}S{\cdot}cm^{-1}$. The effective magnetic moments were lass than the spin-only value of one unpaired electron and no EPR signals from Pd metal ions were observed in any of the compounds, indicating that the Pd ions were diamagnetic and the magnetic moments arose from$(TTF)_n$ or $(TCNQ)_n$ moieties. The experimental evidences revealed that the charge transfer had occurred form $(TTF)_n$ moiety to the central Pd metal ion in 1a, 1b and 1c. Thus the TTF donors were ions in 2a and 2b were diamagnetic Pd(II) oxidation state. In contrast, the Pd metal ion was oxidized to Pd(IV) state in 2c as a result of an addition of $TCNQ^-$anion to $Pd(hfacac)_2$ in methanol. The oxidation states of the Pd metal ions were confirmed using the x-ray photoelectron spectroscopy.

• The Korean Journal of Physiology
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• v.28 no.2
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• pp.143-150
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• 1994

The whole-cell mode of the patch clamp technique was used to study $Ca^{2+}-activated\;Cl^-\;current$ $(I_{Cl_{Ca}})$ in gastric antral myocytes. Extracellular application of caffeine evoked $Ca^{2+}-activated\;current$. In order to isolate the chloride current from background current, all known systems were blocked with specific blockers. The current-voltage relationship of caffeine-induced current showed outward rectification and it reversed at around $E_{Cl^-}$. The shift of reversal potential upon the alteration of external and internal chloride concentrations was well fitted with results which were calculated by the Nernst equation. Extracellular addition of N-phenylanthranilic acid and niflumic acid which are known anion channel blockers abolished the caffeine induced current. Intracellular application of a high concentration of EGTA also abolished this current. Application of c-AMP, c-GMP, heparin, or $AIF^-_4$ made no remarkable changes to this current. Sodium replacement with the impermeable cation N-methylglucamine or with $Cd^{2+}$ rarely affected this current. From the above results it is suggested that the caffeine induced current was a $Cl^-$ current and it was activated by intracellular $Ca^{2+}$.

• Resources Recycling
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• v.33 no.2
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• pp.16-23
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• 2024

The electrolysis for extracting magnesium from seawater or brine primarily involves recovery of magnesium via precipitation as the form of magnesium hydroxide. The technology is classified into cation-exchange membranes (CEM), anion-exchange (AEM) membranes, electrodialysis, and membraneless methods. Recent research has focused on enhancing the efficiency and selectivity of magnesium recovery from seawater or brine containing magnesium, with expectations of effective magnesium recovery even with normal seawater. In a future, the optimization of the selective and efficient recovery of magnesium and various valuable substances through long-term operation of scaled-up systems is crucial with enhancing economic and environmental viability. It is essential to realistically estimate operational costs considering the membrane's lifespan and replacement cycle. Also, detailed and practical process models should be developed based on monitoring data on various factors.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.1
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• pp.38-46
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• 2010

C3GHi, a novel black rice variety developed by conventional breeding has more high contents of cyanidine-3-glucoside (C3G) and a more strong antioxidant than normal black rice. In this study, we investigate the antioxidative potential and anti-diabetic activity of C3GHi and extract of it for the purpose of development of functional materials or replacement meal for diabetic patients. Using in vitro antioxidative activity assay system such as DPPH radical quenching assay, superoxide anion radical scavenging assay, inhibition of lipid peroxidation and DNA breakage assay, C3GHi extract was observed to have more high antioxidative activity than normal black rice breed. The glycemic index of a freeze dried powder of C3GHi brown rice showed $43.7\pm18.8$, which belonged to low GI food (GI of 55 or less). Using in vivo diabetic model such as db/db mice model and streptozotocininduced diabetic model, C3GHi rice extract decrease blood glucose level and inhibit oxidative stress in blood. From the results, we think that the C3GHi varieties have a potential for the functional materials or ingredient of meal replacement for diabetic patients.

• The Korean Journal of Physiology
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• v.26 no.1
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• pp.27-35
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• 1992

We used the whole cell patch clamp technique to examine the ionic basis for the tail current after depolarizing pulse in single atrial myocytes of the rabbit. We recorded the tail currents during various repolarizations after short depolarizing pulse from a holding potential of -70 mV. The potassium currents were blocked by external 4-aminopyridine and replacement of internal potassium with cesium. The current was reversed to the outward direction above +10 mV. High concentrations of intracellular calcium buffer inhibited the activation of the current. Diltiazem and ryanodine blocked it too. These data suggest that the current is activated by intracellular calcium released from sarcoplasmic reticulumn. When the internal chloride concentration was increased, the inward tail current was increased. The current was partially blocked by the anion transport blocker niflumic acid. The current voltage curve of the niflumic acid sensitive current component shows outward rectification and is well fitted to the current voltage curve of the theoretically predicted chloride current calculated from the constant field equation. The currents recorded in rabbit atrial myocytes, with the method showing isolated outward Na Ca exchange current in ventricular cells of the guinea pig, suggested that chloride conductance could be activated with the activation of Na/ca exchange current. From the above results it is concluded that a chloride sensitive component which is activated by intracellular calcium contributes to tail currents in rabbit atrial cells.

• Journal of The Korean Society of Clinical Toxicology
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• v.21 no.2
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• pp.143-150
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• 2023

Purpose: This study aimed to compare the clinical features of methanol and ethylene glycol poisoning. Methods: This single-center retrospective observational study included patients with toxic alcohol poisoning who visited a regional emergency medical center. Patients with methanol and ethylene glycol poisoning from January 2004 to June 2023 were selected for the study using diagnostic codes. Results: Twenty-two patients with toxic alcohol poisoning visited during the study period, with 11 patients for each category. Compared to methanol poisoning, ethylene glycol poisoning patients were more likely to have consumed alcohol for suicidal purposes (n=4 [36.36%] vs. n=8 [72.73%]) and were more likely to be drowsy (n=0 vs. n=6 [54.55%], p=0.016). The anion gap (25.43±8.35 mmol/L vs. 13.22±6.23 mmol/L, p=0.001) and lactic acid levels (1.785 [1.3-2.785] mmol/L vs. 9.90 [4.20-11.81] mmol/L, p=0.007) were higher in ethylene glycol poisoning patients than in methanol poisoning patients. Among alcohol dehydrogenase blockers, oral ethanol was administered to 10 patients (45.45%) (n=4 [36.36%] vs. n=6 [54.55%]), and intravenous ethanol was administered to six patients (n=4 [36.36%] vs. n=2 [18.18%]). Fomepizole was administered to two patients (9.09%) each, and renal replacement therapy was non-significantly more common in patients with ethylene glycol poisoning (n=8 [72.73%] vs. n=3 [27.27%], p=0.128). Three patients had delays in diagnosis and treatment, and while there were no fatalities, one patient was left with permanent vision damage. Conclusion: Because these are uncommon types of poisoning and the clinical presentation is difficult to recognize early, healthcare providers should be familiar with toxic alcohol types and screen for them to ensure proper diagnosis and treatment.

• Bulletin of the Korean Chemical Society
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• v.27 no.9
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• pp.1310-1314
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• 2006

Sulfur-substituted $LiMn_{0.9}Cr_{0.1}O_{2-x}S_x$ $(0\;\leq\;x\;\leq\;0.1)$ layered oxides have been prepared by solid state reaction under inert atmosphere. From powder X-ray diffraction analyses, all the present lithium manganates were found to be crystallized with monoclinic-layered structure. Electrochemical measurements clearly demonstrated that, in comparison with the pristine $LiMn_{0.9}Cr_{0.1}O_2$, the sulfur-substituted derivatives exhibit smaller discharge capacities for the entire cycle range but the recovery of discharge capacity after the initial several cycles becomes faster upon sulfur substitution. The effect of the sulfur substitution on the chemical bonding nature of $LiMn_{0.9}Cr_{0.1}O_{2-x}S_x$has been investigated using X-ray absorption spectroscopic (XAS) analyses at Mn and Cr K-edges. According to Mn K-edge XAS results, the trivalent oxidation state of manganese ion remains unchanged before and after the substitution whereas the local structure around manganese ions becomes more distorted with increasing the substitution rate of sulfur. On the other hand, the replacement of oxygen with sulfur has negligible influence on the local atomic arrangement around chromium ions, which is surely due to the high octahedral stabilization energy of $Cr^{+III} $ ions. Based on the present experimental findings, we have suggested that the decrease of discharge capacity upon sulfur substitution is ascribable to the enhanced structural distortion of $MnO_6$ octahedra and/or to the formation of covalent Li-S bonds, and the accompanying improvement of cyclability would be related to the depression of Mn migration and/or to the pillaring effect of larger sulfur anion.