• Journal of the Korean Magnetics Society
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• v.13 no.3
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• pp.121-126
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• 2003

The electromagnetic properties and microstructures of the basic composition of (N $i_{0.2}$C $u_{0.2}$Z $n_{0.6}$)$_{1.085}$(F $e_2$ $O_3$)$_{0.915}$ were invested by changing of the additive Sn $O_2$, CaO amounts and ferrite processes. There is no variation of grain size by changing additive amount. It can reduce the total loss when (N $i_{0.2}$C $u_{0.2}$Z $n_{0.6}$)$_{1.085}$(F $e_2$ $O_3$)$_{0.915}$ composition sintered at 1150 $^{\circ}C$ better than 130$0^{\circ}C$. Additive CaO confirmed of useful addition for the reduce total loss, because it increasing sintering density. Decreasing total loss were observed by adding both Sn $O_2$ 0.06 wt％ and CaO 0.4 wt％.

• BMB Reports
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• v.49 no.5
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• pp.276-281
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• 2016

Corosolic acid (CA), a triterpenoid compound isolated from Lagerstroemia speciosa L. (Banaba) leaves, exerts anti-inflammatory effects by regulating phosphorylation of interleukin receptor- associated kinase (IRAK)-2 via the NF-κB cascade. However, the protective effect of CA against endotoxic shock has not been reported. LPS (200 ng/mL, 30 min) induced phosphorylation of IRAK-1 and treatment with CA (10 μM) significantly attenuated this effect. In addition, CA also reduced protein levels of NLRP3 and ASC which are the main components of the inflammasome in BMDMs. LPS-induced inflammasome assembly through activation of IRAK-1 was down-regulated by CA challenge. Treatment with Bay11-7082, an inhibitor of IκB-α, had no effect on CA-mediated inhibition of IRAK-1 activation, indicating that CA-mediated attenuation of IRAK-1 phosphorylation was independent of NF-κB signaling. These results demonstrate that CA ameliorates acute inflammation in mouse BMDMs and CA may be useful as a pharmacological agent to prevent acute inflammation.

• Applied Microscopy
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• v.28 no.1
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• pp.91-105
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• 1998

The present study is undertaken to investigate the hypertrophical changes of the corpus allatum (corpora allata, CA) after the ovariectomy in Blattella germanica. In particular, the ultrastructural aspects of the normal and ovariectomized conditions, and induced factors of the hypertrophic phenomenon are focused. Ultrastructure of the CA from an immediately emergent adult is similar to that of the last larval stage that has stopped secreting juvenile hormone. The CA is composed of undifferentiated cells, exhibiting an electron-lucent matrix, a few mitochondria and less smooth endoplasmic reticulum. The karyoplasm occupy most of the cytoplasm. Electron-dense materials are filled with the intercellular spaces and gap junctions are also found. Almost no ultrastructural changes have been noticed during seven days until the oviposition. However, considerable changes in structure have been detected soon after the oviposition. Mitochondria are increased dramatically in number and cristae, and changed to the filamentous form with a high electron density. In addition, Golgi complexes, microtubules, and polysomes are also increased. After an oviposition, the total volume of the CA are decreased again. The volume of the CA are increased continuously, hypertrophy, after the ovariectomy. Morphological aspects of the CA in an early stage after the removal are similar to the structure of the secondary egg maturation. Large and electron dense globules are observed in the ovariectomized CA cytoplasms and they are present in those cells for a long period of time. Yet such a hypertrophical phenomenon occur only in the specific cells. The hypertrophy are caused by hollowing the part of the CA cells and later filling such site with polysomes. In 42 days after the ovariectomy, the nuclear membranes disappear in the CA cells, thus, exhibiting the prokaryotic-like features. Some results of the current study will contribute to the establishment of the model that explain unusual changes accompanied by certain treatment in insects and/or further in animals.

• Bulletin of the Korean Chemical Society
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• v.33 no.4
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• pp.1165-1169
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• 2012

The fluorescence intensity of DNA-intercalated ethidium with [ethidium]/[DNA base] being 0.005 was quenched upon the binding of another intercalating ligand, meso-tetrakis(N-methylpyridinium-4-yl)porphyrin (TMPyP). Addition of $Ca^{2+}$ enhanced the quenching efficiency. The range of separations between donor and acceptor molecules, within which total quenching occurs, was calculated using a one-dimensional resonance energy transfer mechanism to be 9.5 base-pairs or $32.3{\AA}$ in the absence of $Ca^{2+}$ ions. The distance increased to 18.7 base-pairs or about $63.6{\AA}$ in the presence $100{\mu}M$ $Ca^{2+}$. Considering that (1) $Ca^{2+}$ had little effect on the binding modes of ethidium and TMPyP, which was investigated by reduced linear dichroism and (2) spectral overlap between the emission spectrum of ethidium and the absorption spectrum of TMPyP was maintained in the presence of $Ca^{2+}$, contributions from orientation factor and spectral overlap to $Ca^{2+}$-induced enhancement in DNA mediated energy transfer was limited. Although there is no direct evidence, electron transfer along the DNA stem may accompany the observed fluorescence quenching. In this respect, DNA bound $Ca^{2+}$ act as a partially conducting medium.

• The Korean Journal of Physiology and Pharmacology
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• v.11 no.1
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• pp.21-30
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• 2007

The present study was designed to establish comparatively the inhibitory effects of cilnidipine(CNP), nifedipine(NIF), and $\omega$-conotoxin GVIA(CTX) on the release of CA evoked by cholinergic stimulation and membrane depolarization from the isolated perfused model of the rat adrenal medulla. CNP(3 ${\mu}M$), NIF(3 ${\mu}M$), and CTX(3 ${\mu}M$) perfused into an adrenal vein for 60 min produced greatly inhibition in CA secretory responses evoked by ACh($5.32{\times}10^{-3}M$), DMPP($10^{-4}M$ for 2 min), McN-A-343($10^{-4}M$ for 2 min), high $K^+(5.6{\times}10^{-2}M)$, Bay-K-8644($10^{-5}M$), and cyclopiazonic acid($10^{-5}M$), respectively. For the CA release evoked by ACh and Bay-K-8644, the following rank order of potency was obtained: CNP>NIF>CTX. The rank order for the CA release evoked by McN-A-343 and cyclopiazonic acid was CNP>NIF>CTX. Also, the rank orders for high $K^+$ and for DMPP were NIF>CTX>CNP and NIF>CNP>CTX, respectively. Taken together, these results demonstrate that all voltage-dependent $Ca^{2+}$ channels(VDCCs) blockers of cilnidipine, nifedipine, and $\omega$-conotoxin GVIA inhibit greatly the CA release evoked by stimulation of cholinergic(both nicotinic and muscarinic) receptors and the membrane depolarization without affecting the basal release from the isolated perfused rat adrenal gland. It seems likely that the inhibitory effects of cilnidipine, nifedipine, and $\omega$-conotoxin GVIA are mediated by the blockade of both L- and N-type, L-type only, and N-type only VDCCs located on the rat adrenomedullary chromaffin cells, respectively, which are relevant to $Ca^{2+}$ mobilization. It is also suggested that N-type VDCCs play an important role in the rat adrenomedullary CA secretion, in addition to L-type VDCCs.

• Resources Recycling
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• v.16 no.4
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• pp.33-39
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• 2007

Titanium scrap was re-melted and refined by using a DC-ESR (Direct Current Electro Slag Remelting) apparatus. A graphite rod was used as an anode. The used slag was $CaF_2-TiO_2-CaO$ slag system. The effect of slag composition on the shape and oxygen content of re-melted ingot was studied. The titanium ingot was produced very well from the $CaF_2-TiO_2$ slag system, and the oxygen content of the ingot was less than that of titanium scrap. The addition of CaO into $CaF_2-TiO_2$ slag system made the bad shape of titanium ingot. The oxygen content of the ingot was also higher than that of titanium scrap.

• Korean Journal of Pharmacognosy
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• v.46 no.2
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• pp.109-115
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• 2015

This study was investigated the radical scavenging effect and the protective activity of caffeic acid (CA) against oxidative stress. CA showed strong 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) and hydroxyl radical ( OH) scavenging activity, showing 42.00% and 87.22% at 5 μM concentration of DPPH and ·OH scavenging activity, respectively. Furthermore, we studied protective activity of CA from amyloid beta (A${\beta}$_25-35) and lipopolysaccharide (LPS) induced neuronal cell damage and neuronal inflammation using C6 glial cells. The treatment of A${\beta}$_25-35 to C6 glial cell showed declines in cell viability and high generation levels of reactive oxygen species (ROS). However, the treatment of CA increased cell viability. The treatment of 5 ${{\mu}M}$ CA led to the elevation of cell viability from 59.28% to 81.22%. In addition, the production of ROS decreased cellular levels of ROS by the treatment of CA. The treatment of LPS to C6 glial cells increased significant elevation of nitric oxide (NO) production, while CA decreased NO production significantly. The production of NO increased by the treatment of LPS to 131.08%, while CA at the concentration of 1 ${{\mu}M}$ declined the NO production to 104.86%. The present study indicated thatCA attenuated A${\beta}$_25-35-induced neuronal oxidative stress and inflammation by LPS, suggesting as a promising agent for the neurodegenerative diseases.

• Nutrition Research and Practice
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• v.7 no.4
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• pp.294-301
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• 2013

In this study, we examined the hepatic anti-steatosis activity of carnosic acid (CA), a phenolic compound of rosemary (Rosmarinus officinalis) leaves, as well as its possible mechanism of action, in a high-fat diet (HFD)-fed mice model. Mice were fed a HFD, or a HFD supplemented with 0.01% (w/w) CA or 0.02% (w/w) CA, for a period of 12 weeks, after which changes in body weight, blood lipid profiles, and fatty acid mechanism markers were evaluated. The 0.02% (w/w) CA diet resulted in a marked decline in steatosis grade, as well as in homeostasis model assessment of insulin resistance (HOMA-IR) index values, intraperitoneal glucose tolerance test (IGTT) results, body weight gain, liver weight, and blood lipid levels (P < 0.05). The expression level of hepatic lipogenic genes, such as sterol regulating element binding protein-1c (SREBP-1c), liver-fatty acid binding protein (L-FABP), stearoyl-CoA desaturase 1 (SCD1), and fatty acid synthase (FAS), was significantly lower in mice fed 0.01% (w/w) CA and 0.02% (w/w) CA diets than that in the HFD group; on the other hand, the expression level of ${\beta}$-oxidation-related genes, such as peroxisome proliferator-activated receptor ${\alpha}$ (PPAR-${\alpha}$), carnitine palmitoyltransferase 1 (CPT-1), and acyl-CoA oxidase (ACO), was higher in mice fed a 0.02% (w/w) CA diet, than that in the HFD group (P < 0.05). In addition, the hepatic content of palmitic acid (C16:0), palmitoleic acid (C16:1), and oleic acid (C18:1) was significantly lower in mice fed the 0.02% (w/w) CA diet than that in the HFD group (P < 0.05). These results suggest that orally administered CA suppressed HFD-induced hepatic steatosis and fatty liver-related metabolic disorders through decrease of de novo lipogenesis and fatty acid elongation and increase of fatty acid ${\beta}$-oxidation in mice.

• YAKHAK HOEJI
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• v.57 no.1
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• pp.24-31
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• 2013

Although statins, inhibitors of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase, have been shown to increase melanin synthesis, the exact mechanism of this action is not fully understood. In this study we investigated the possible involvement of intracellular $Ca^{2+}$ signal in the mechanism of stimulation of melanin synthesis induced by lovastatin in B16 cells. Lovastatin stimulated the production of melanin in a dose-dependent manner in the cells. Treatment with mevalonate, FPP and GGPP, precursors of cholesterol, did not significantly suppress the lovastatin-induced melanin production, suggesting that inhibition of cholesterol synthesis may not be involved in the mechanism of the action of lovastatin. In addition, lovastatin did not significantly alter the cAMP concentration and the stimulated production of melanin by lovastatin was not significantly changed by treatment with H89, a potent inhibitor of protein kinase A, which demonstrates that cAMP pathway may not be involved. However, lovastatin increased intracellular $Ca^{2+}$ concentration in a dose-related fashion. Treatment with EGTA, an extracellular $Ca^{2+}$ chelator did not significantly alter the lovastatin-induced intracellular $Ca^{2+}$ increase and melanin synthesis, whereas intracellular $Ca^{2+}$ reduction with BAPTA/AM and intracellular $Ca^{2+}$ release blockers (dantrolene and TMB-8) completely blunted these actions of lovastatin. Taken together, these results suggest that the intracellular $Ca^{2+}$ release may play an important role in the lovastatin-induced stimulation of melanin synthesis in B16 cells. These results further suggest that lovastatin may be useful for the treatment of hypopigmentation disorders, such as vitiligo.

• Journal of Plant Biology
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• v.23 no.1
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• pp.17-25
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• 1980

Kidneybean(Phaseolus vlgaris L.) and buckwheat(Fagopyrum esculentum M$\"{O}$nch) seedlings cultured with Hoagland solution to the height of 7 to 10cm in the earthern pot containing sand were used for experimental plants. One group of the plants was irrigated with Hoagland solution composed of various Al concentrations of 0 to 1,000 ppm containing 50ppm Ca, and the other group was irrigated with Hoagland solution composed of various Ca concentrations of 0 to 1,000ppm containing 100ppm Al for a month during June and July. By Al-surplus over 100ppm, the margins of backwheat leaves were curied down and turned into yellow-brown necrosis simialr to Ca-deficiency, and the old kidney bean leaves showed marginal and veinal chlorosis in addition to the early shedding of leaves. With Al-surplus of 100ppm the content of chlorophyll a and b in both plants was decreased by 30~40%. The ratio 3/1 of chlorophyll a/b was not altered by Al-surplus and Ca-deficienty at an early stage, but it was affected markedly at a final stage of growth. Leaf respiration with 100ppm Al containing 50pm Ca was slightly affected in buckwheat, but decreased by 20% in kidneybean. With Al-surplus of 100ppm the ATP content was decreased by 32% in the kidneybean leaves and by 80% in buckwheat leaves, whereas with Ca-deficiency it was decreased by 72% in kidneybean and by 90% in buckwheat. The rhythm of ATP level showed self-relience without being affected by light or temperature under the green house condition although by Al-s rplus and Ca-deficiency the ATP level of the rhythm was lower than that of control.trol.