• Journal of the East Asian Society of Dietary Life
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• v.10 no.2
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• pp.153-159
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• 2000

The effect of boiling with apple vinegar and citric acid on the dissolution of Ca, Mg, and P out of pork rib bone during stew preparation was investigated. As the concentration (0, 1, 2. 4%) of apple vinegar and citric acid increased, the amount of Ca, Mg, and P dissolved out of the rib bone increased compared with the control. The increase in boiling time(3, 6, 9, 12 hour) also showed the same result. Between the two acid condiments citric acid extracted more Ca, Mg, and P than the apple vinegar at the same concentration. The pH of the pork rib bone stew added with the acid condiments increased gradually during the boiling process. Between the two acid condiments the apple vinegar extracted more amino acids and protein than citric acid at the same concentration.

• YAKHAK HOEJI
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• v.41 no.6
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• pp.773-781
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• 1997

The activity of $Ca^{2+}$calmodulin (CaM)-dependent protein kinase Ia (CaM kinase Ia) is shown to be regulated through direct phosphorylation by CaM kinase I kinase (CaMK IK). In the present study, three distinct CaMKIK peaks were separated from Q-Sepharose colunm chromatography of pig brain homogenate using a Waters 650 Protein Purification System. The purified CaMKIK from the major peak potently and rapidly enhanced CaM kinase Ia activity, reaching a maximal stimulation within 2min at the concentrations of 12-15nM. The activated state of CaM kinase Ia is characterized by a markedly enhanced $V_{max}4 as well as significantly decreased $K_m\;and\;K_a$ values toward peptide substrate and CaM, respectively. These observations suggest the activation process of CaM kinase Ia. The phosphorylation of CaM kinase Ia by CaMKIK may induce its conformational change responsible for the alterations in the kinetic properties, which ultimately leads to the rapid enzyme activation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.6
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• pp.255-261
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• 2016

$CaCO_3$ was applied in various industries including rubber, plastics, paint, paper, food additives, and acid neutralizer, etc., owing to its excellent physical and chemical characteristics as well as various appearances of crystals and many reserves. In particular, research on controlling the structure and shape of $CaCO_3$ has attracted considerable attention recently, because the whiteness and physical characteristics of $CaCO_3$ depend on the size and shapes of the particles. In this study, $CaCO_3$ was synthesized using $CaCl_2$ and $(NH4)_2CO_3$, which has multi-shapes and structures, using a self-assembly method with a hydrothermal method. The structure and morphology of the $CaCO_3$ could be controlled by adjusting the pH and precursor concentration. In particular, the pH adjustment appeared to be a critical factor for the morphology and crystal form. In addition, the calcite and cubic shape were obtained at pH 7, while the mixed calcite, aragonite structure, and rod shapes appeared at pH 7 and over. Through an analysis of the particle formation process, the formation of the calcium carbonate particles was confirmed. The physicochemical properties of the synthesized $CaCO_3$ were analyzed by SEM, XRD, EDS, FTIR, and TG/DTA.

• Progress in Medical Physics
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• v.11 no.1
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• pp.29-38
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• 2000

The signal transduction pathway for most neurotransmitter induced inhibition of $Ca^{2+}$ channels in sympathetic neurons involves a G-protein mediated, membrane-delimited mechanism without the participation of any known protein kinase. However, activation of protein kinase C (PKC) has been proposed as one of the intracellular mechanisms mediating some neurotransmitter induced $Ca^{2+}$ channel inhibition. In the present study, we investigated the effects of phorbol-12, 13-dibutyrate (PDBu) on $Ca^{2+}$ channel currents of acutely dispersed neurons from adult rat superior cervical ganglion (SCG) neurons using whole cell variant of the patch clamp technique. PDBu (500 nM), the activator of PKC, increased $Ca^{2+}$ channel currents and retarded the deactivation of tail currents. The effects of PDBu were voltage dependent and the maximal increase in the current amplitudes was observed between -10 to 10 mV (n=4). PDBu attenuated $Ca^{2+}$ current inhibition induced by norepinephrine (NE), which modulates $Ca^{2+}$ channels via a pertussis toxin (PTX)-sensitive pathway. Inhibition of PDBu by staurosporine (1 $\mu$M) blocked the effects of PDBu on current amplitudes and NE-induced G-protein mediated inhibition of $Ca^{2+}$ currents. Further experiment should be done to know if G-protein or $Ca^{2+}$ channel itself is the target of PKC phosphorvlation.phosphorvlation.

• Proceeding of EDISON Challenge
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• 2017.03a
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• pp.703-707
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• 2017

배아줄기세포 유래 심근세포는 심근경색 등으로 심장이 제 기능을 다 하지 못할 때 치료적 목적으로 주사하여 환자의 심기능을 정상화 시키는 데에 쓰인다. 배아줄기세포 유래 심근세포는 페이스메이커 활동을 보이면서 막전압 고정상태에서도 주기적인 일과성 내향전류를 보이는 특징을 갖고 있다. 본 연구는 기존에 발표된 배아줄기세포 유래 심근세포의 시뮬레이션 모델을 이용하여 어떻게 하여 페이스메이커 활동이 나타나는지 그 기전을 밝히고자 하였다. 세포내 모든 이온을 고정하였을 때 모델 세포는 여전히 페이스메이커 활동을 보였다. 근장그물내 칼슘 이온을 고정하였을 때도 모델 세포는 페이스메이커 활동을 보였다. 그러나 Na-Ca 교환 전류를 차단하였을 때는 모델 세포의 페이스메이커 활동이 사라졌는데, 여기서 L-type $Ca^{2+}$ 전류의 칼슘 의존성 비활성화 기전을 제거하자 페이스메이커 활동이 지속되었다. 또한 Na-Ca 교환전류와 L-type $Ca^{2+}$ 전류만으로는 페이스메이커 활동이 보이지 않았으나 L-type $Ca^{2+}$ 전류의 크기를 3배로 증가시키자 페이스메이커 활동이 다시 나타남을 확인하였다. 따라서, 배아줄기세포 유래 심근세포의 페이스메이커 활동은 Na-Ca 교환전류와 L-type $Ca^{2+}$ 전류의 역할이 매우 중요하며, Na-Ca 교환전류는 L-type $Ca^{2+}$ 전류가 비활성화되지 않도록 칼슘 이온의 농도를 조절하는 데에 큰 역할을 하는 것으로 결론을 내렸다.

• Proceeding of EDISON Challenge
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• 2017.03a
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• pp.698-702
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• 2017

배아줄기세포 유래 심근세포는 심근경색 등으로 심장이 제 기능을 다 하지 못할 때 치료적 목적으로 주사하여 환자의 심기능을 정상화 시키는 데에 쓰인다. 배아줄기세포 유래 심근세포는 페이스메이커 활동을 보이면서 막전압 고정상태에서도 주기적인 일과성 내향전류를 보이는 특징을 갖고 있다. 본 연구는 기존에 발표된 배아줄기세포 유래 심근세포의 시뮬레이션 모델을 이용하여 어떻게 하여 페이스메이커 활동이 나타나는지 그 기전을 밝히고자 하였다. 세포내 모든 이온을 고정하였을 때 모델 세포는 여전히 페이스메이커 활동을 보였다. 근장그물내 칼슘 이온을 고정하였을 때도 모델 세포는 페이스메이커 활동을 보였다. 그러나 Na-Ca 교환 전류를 차단하였을 때는 모델 세포의 페이스메이커 활동이 사라졌는데, 여기서 L-type $Ca^{2+}$ 전류의 칼슘 의존성 비활성화 기전을 제거하자 페이스메이커 활동이 지속되었다. 또한 Na-Ca 교환전류와 L-type $Ca^{2+}$ 전류만으로는 페이스메이커 활동이 보이지 않았으나 L-type $Ca^{2+}$ 전류의 크기를 3배로 증가시키자 페이스메이커 활동이 다시 나타남을 확인하였다. 따라서, 배아줄기세포 유래 심근세포의 페이스메이커 활동은 Na-Ca 교환전류와 L-type $Ca^{2+}$ 전류의 역할이 매우 중요하며, Na-Ca 교환전류는 L-type $Ca^{2+}$ 전류가 비활성화되지 않도록 칼슘 이온의 농도를 조절하는 데에 큰 역할을 하는 것으로 결론을 내렸다.

• Journal of Ginseng Research
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• v.23 no.4
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• pp.230-234
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• 1999

Potassium channels play an important role in regulating vascular smooth muscle tone. Four types of $K^+$ channels areknown to be expressed in vascular smooth muscle cells, and maxi $Ca^{2+}-activated\;K^+$ channel $(BK_{Ca})$ is a dominant type of $K^+$ channels in these cells. Because total ginseng saponins and ginsenoside $Rg_3$ cause vasodilation with unclear mechanisms, we hypothesized that total ginseng saponins and ginsenoside $Rg_3$ induce vasodilation via activation of maxi $Ca^{2+}-activated\;K+$ channels. Whole-cell BKe. currents were voltage-dependent with half maximum activation at -14 mV, and the currents were sensitive to nanomolar ChTX and millimolar TEA. External application of total ginseng saponins increased the anlplitude of the whole-cell BKe. current in a concentration-dependent manner. Single-channel analysis indicates that total ginseng saponins caused the channel opening for a longer period of time. Ginsenoside $Rg_3$ increased the amplitude of whole-cell $K_{Ca}$ currents without affecting voltage dependence of the currents and increased single-channel open time. Hence, the results suggest that ginseng saponin-induced vasodilation may be due to activation of $K_{Ca}$.

• Journal of Veterinary Clinics
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• v.32 no.2
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• pp.135-140
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• 2015

Trans-10, cis-12-conjugated linoleic acid (t10c12-CLA) has been shown to participate in the regulation of anti-inflammatory effects. The objectives of this study were to examine the effects of t10c12-CLA on reactive oxygen species (ROS) and nitric oxide (NO) production and nuclear factor-kappaB (NF-${\kappa}B$) activation in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells and to determine whether these effects were associated with change of intracellular calcium ion ($Ca^{2+}$). ROS production was increased in LPS-stimulated RAW 264.7 cells, and this effect was suppressed by 1,2-bis-(o-aminophenoxy) ethane-N,N,N',N'-tetraacetic acid-acetoxymethyl ester (BAPTA/AM), a calcium chelator. t10c12-CLA suppressed ROS production in LPS-stimulated RAW 264.7 cells, which was further more decreased by treatment with BAPTA/AM. These indicated that t10c12-CLA decreases $Ca^{2+}$-dependent ROS production in LPS-stimulated RAW 264.7 cells. Similarly, NF-${\kappa}B$ p65 DNA binding activity and NO production were decreased by treatment with either t10c12-CLA, BAPTA/AM, or t10c12-CLA and BAPTA/AM combination. However, there were no differences between t10c12-CLA and BAPTA/AM treatment in NO production of LPS-stimulated RAW 264.7 cells. These data indicate that t10c12-CLA inhibits the increases in ROS and NO production and the NF-${\kappa}B$ activation in LPS-stimulated condition. These results suggested that CLA exerts potent anti-inflammatory effects by suppression of LPS-induced ROS and NO production, and NF-${\kappa}B$ activationn via $Ca^{2+}$-dependent pathway.

• Journal of Soil and Groundwater Environment
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• v.11 no.3
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• pp.12-19
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• 2006

In this study, the stability of Ca-bentonite colloids from Gyeongju area was studied by investigating the changes in the size of the bentonite colloids using a dynamic light scattering method depending on the geochemical conditions such as pH and ionic strength. Kinetic and equilibrium coagulation behavior of the bentonite colloids was investigated by changing the pH and ionic strength of the bentonite suspensions. The results showed that the stability of the bentonite colloids strongly depended upon contact time, pH, and ionic strength. It was also shown that the bentonite colloids were unstable at higher ionic strength greater than 0.01 M $NaClO_4$ at whole pH values considered. In addition, the stability ratio Wand the critical coagulation concentration (CCC) were also calculated using the data from the kinetic coagulation experiments. The stability ratio W was decreased as the ionic strength increased and varied with pH depending on the ionic strength. The CCC of the Ca-bentonite colloids was about 0.05 M $NaClO_4$ around pH 7.

• Korean Journal of Microbiology
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• v.46 no.1
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• pp.80-85
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• 2010

Two different ${\alpha}$-amylase isozymes (AMY1 and AMY2) found in barley malt share up to 80% of amino acid sequence identity with each other, but their enzymatic properties differ remarkably. AMY1 shows the highest activity at low concentration of calcium ion, while AMY2 is highly active at high calcium concentration. Meanwhile, BASI (Barley ${\alpha}$-Amylase/Subtilisin Inhibitor) protein specifically inhibits only AMY2. In the present study, three separate regions in AMY genes (I, II, and III) were assigned on the basis of restriction enzyme sites and four kinds of chimeric amylases have been obtained by swapping a part of regions with each other. Each chimera gene was successfully over-expressed in Pichia pastoris. From the results of enzymatic characterization, both AMY211 and AMY122 showed the mixed or intermediate type of calcium-dependent activity between AMY1 and 2. Meanwhile, only AMY221 chimera could be significantly inhibited by BASI protein. As a result, it can be proposed that some amino acid residues in the region I and II, except region III, of barley ${\alpha}$-amylases play very important roles in calcium-dependency and interaction with BASI.