• Proceedings of the Korean Biophysical Society Conference
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• 1999.06a
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• pp.61-62
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• 1999

;The mechanisms inducing hypertension are actively investigated and are still challenging topics. Basically hypertension must be caused by the disorder of $Ca^{2+}$ metabolism in vascular smooth muscle, such as the increase of $Ca^{2+}$ influx, the decrease of ci+ efflux, or the change of sensitivity of contractile protein etc. The one of cause of the increase of ci+ influx may be the change of ci+ channel activity. Even though the relationships of ci+ channel activity and hypertension were studied using various hypertension models, still it is not clear how much change of $Ca^{2+}$ channel activity in diabetes mellitus (DM) induced hypertension is occurred. We induced DM hypertension in SD rat and compared the $Ca^{2+}$ channel activity with age-matched normotensive SD rat. For inducing DM hypertension, left kidney was removed with 200 gm rat and, after 1 month, 60 mg/kg of streptozotocin was injected into peritoneal space to induce diabetes mellitus. Usually after 4-6 weeks, hypertension was fully induced. For isolating vascular smooth muscle cells (VSMC), we used mesenteric arteriole (3rd - 4th branch of mesenteric artery) of which diameter is below 150 urn. VSMCs were isolated enzymatically. $Ca^{2+}$ current was measured using whole cell patch clamp technique. All experiments were performed at $37^{\circ}C$. The cell membrane area of VSMC of DM hypertensive rat is larger than that of control VSMC($36.6{\pm}3.64{\;}pF{\;}vs{\;}22.4{\pm}1.29{\;}pF, {\;}mean{\pm}S.E.$) When we compared the current amplitude, the $Ca^{2+}$ current amplitude in VSMC of DM hypertensive rat is much larger than that in VSMC of normotensive age-matched rat. After $Ca^{2+}$ current amplitude was normalized by cell membrane area, the current amplitude in DM hypertension is increased to $249.1{\pm}15.9{\;}%{\;}(mean{\pm}S.E.M)$, which means the ;absolute current amplitude is about 4 times larger in DM hypertension. When we compared the steady state activation and inactivation. there were no noticeable differences. From these results. one of cause of the DM hypertension is due to the increase of $Ca^{2+}$ current amplitude. But it need further study why the $Ca^{2+}$ current is so large in VSMC of DM hypertension and how much $Ca^{2+}$ influx through $Ca^{2+}$ channel contribute to the increase of intracellular $Ca^{2+}$ and eventually contribute to development of hypertension.ypertension.

• Archives of Pharmacal Research
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• v.29 no.5
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• pp.343-347
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• 2006

A new flavanone Persinol (1) and the new flavanone glucosides persinosides A (2) and B (3), along with known flavonoids (4 and 5) have been isolated from the ethyl acetate soluble fraction of the whole plants of Aerva persica. Their structures were elucidated on the basis of extensive analysis of nuclear magnetic resonance (1D & 2D-NMR) spectral data. All of them showed profound antioxidative activities by DPPH and cytochrome-c-reduction assays using the HL-60 cell culture system.

• Korean Journal of Microbiology
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• v.51 no.4
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• pp.407-418
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• 2015

This study is focused on establishing the optimal conditions to enhance the production of antilisterial substances by Lactobacillus paracasei BK57 isolated from Baikkimchi. In addition, the growth and in situ lactic acid and bacteriocin production of this strain were investigated during the manufacture of fresh cheese. And then the efficacy of using Lactobacillus starter as a protective culture to improve the safety of fresh cheese against Listeria monocytogenes KCTC 3569 was estimated. Maximum growth rate and activity of antibacterial substances were obtained in Lactobacilli MRS broth at $37^{\circ}C$ with controlled pH 6.0 after 30 h of incubation under aerobic condition. However, the growth rate and antimicrobial activity of bacteriocin produced in whole milk supplemented with yeast extract (2.0%) as a substrate were lower than those obtained in MRS broth. Live cells and cell-free culture supernatant of BK57 strain were effective in the suppression of L. monocytogenes in milk, whereas the inhibitory of the bacteriocin obtained from BK57 strain was higher in BHI broth than in milk. During storage at $4^{\circ}C$ and $15^{\circ}C$ for 6 days, no significant difference was found in the cell viability and antimicrobial activity of BK 57 strain in fresh cheese. In samples held at two temperatures, there was at least a 15% reduction in the numbers of the pathogen in fresh cheese artificially contaminated with approximately $10^5CFU/ml$ of L. monocytogenes within 6 days. Our results demonstrated the usefulness of L. paracasei BK57 having antilisterial activity as a biopreservative in the cheese making process.

• The Korean Journal of Physiology and Pharmacology
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• v.7 no.4
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• pp.223-229
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• 2003

Using phospholipase D1 (PLD1)-overexpressing PC12 (PLD1-PC12) cells, the regulatory roles of PLD1 on ATP-induced currents were investigated. In control and PLD1-PC12 cells, ATP increased PLD activity in an external $Ca^{2+}$ dependent manner. PLD activity stimulated by ATP was substantially larger in PLD1-PC12 cells than in control cells. In whole-cell voltage-clamp mode, ATP induced transient inward and outward currents. The outward currents inhibited by TEA or charybdotoxin were significantly larger in PLD1-PC12 cells than in control cells. The inward currents known as $Ca^{2+}$ permeable nonselective cation currents were also larger in PLD1-PC12 cells than in control cells. However, the difference between the two groups of cells disappeared in $Ca^{2+}$-free external solution, where ATP did not activate PLD. Finally, ATP-induced $^{45}Ca$ uptakes were also larger in PLD1-PC12 cells than in control cells. These results suggest that PLD enhances ATP-induced $Ca^{2+}$ influx via $Ca^{2+}$ permeable nonselective cation channels and increases subsequent $Ca^{2+}$-activated $K^+$ currents in PC12 cells.

• The Korean Journal of Physiology and Pharmacology
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• v.15 no.6
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• pp.415-422
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• 2011

Previously, we reported that besides retinal ganglion cell (RGC) spike, there is ~10 Hz oscillatory rhythmic activity in local field potential (LFP) in retinal degeneration model, rd1 mice. The more recently identified rd10 mice have a later onset and slower rate of photoreceptor degeneration than the rd1 mice, providing more therapeutic potential. In this study, before adapting rd10 mice as a new animal model for our electrical stimulation study, we investigated electrical characteristics of rd10 mice. From the raw waveform of recording using $8{\times}8$ microelectrode array (MEA) from in vitro-whole mount retina, RGC spikes and LFP were isolated by using different filter setting. Fourier transform was performed for detection of frequency of bursting RGC spikes and oscillatory field potential (OFP). In rd1 mice, ~10 Hz rhythmic burst of spontaneous RGC spikes is always phase-locked with the OFP and this phase-locking property is preserved regardless of postnatal ages. However, in rd10 mice, there is a strong phase-locking tendency between the spectral peak of bursting RGC spikes (~5 Hz) and the first peak of OFP (~5 Hz) across different age groups. But this phase-locking property is not robust as in rd1 retina, but maintains for a few seconds. Since rd1 and rd10 retina show phase-locking property at different frequency (~10 Hz vs. ~5 Hz), we expect different response patterns to electrical stimulus between rd1 and rd10 retina. Therefore, to extract optimal stimulation parameters in rd10 retina, first we might define selection criteria for responding rd10 ganglion cells to electrical stimulus.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.3
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• pp.599-607
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• 2009

Prunellae Spica is the spike or whole plant of Prunella vulgaris Linne, which has been used for clearing heat from the liver, brightening the eyes and treating headache in traditional oriental medicines. This study was conducted to evaluate the inhibitory effects of the aqueous extract of Prunellae Spica (PSE; PS extract) on the production of NO and PGE2 in LPS-activated Raw 264.7 cells. Cell viability was determined by MTT assay, and all three doses of PS extract (0.03, 0.1 and 0.3 mg/ml) had no significant cytotoxicity during the entire experimental period. The cells were treated with 1 ${\mu}g/ml$ of LPS 1 h before adding PS extract, and increased NO and PGE2 production were detected in LPS-activated cells compared to control. However, these increases were dose-dependently attenuated by treatment with PS extract. The inhibition of NO by PS extract was due to the suppression of iNOS expression via inhibition of $NF{\kappa}B$ nuclear translocation and proteolytic degradation of $I{\kappa}B{\alpha}$. The decreased level of PGE2 was derived from inhibition of COX-2 activity, but expression of COX-2 protein was not affected by PS extract. Moreover, PS extract reduced the elevated production of IL-${\beta}$ and IL-6 by LPS. These results demonstrate that PS extract has inhibitory effects on the production of NO and PGE2 as a consequence of the reduction of proinflammatory cytokines, especially IL-${\beta}$ and IL-6 in LPS-activated Raw 264.7 cells.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.21 no.1
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• pp.1-12
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• 1999

The purpose of this study was to evaluate the healing process of the calvarial defect filled with hydroxylapatite(HA) and $TGF-{\beta}$ in Rat. 72 Sprague-Dawly rats were divided into 3 groups, control and two experimental groups. Bony defect were artificially prepared in the calvaria of all 72 rats and followed by implantation of HA (experimental group of 24 rats) and HA+$TGF-{\beta}$(another experimental group of 24 rats) into the defects. Sequential sacrifice was performed at 1, 2, 4, 6, 8, 12 weeks of experiment. Obtained specimen was stained with Hematoxylin and Eosin, Masson's Trichrome and Immunohistochemistry. The results were as follows, 1. Granulation tissue was prominent on control group in 1 and 2 weeks. Bony defects were filled with dense fibrous tissue through the whole experimental period and osteoinduction could not be observed in all groups. 2. Inflammatory cell infiltration was prominent on control group in 1 and 2 weeks and osteoclastic activity was high in HA implanted experimental group at 1 and 2 weeks. 3. Inflammatory cell infiltration was less and maturation of fibrous tissue could be found on HA+$TGF-{\beta}$ implanted experimental group at 1 and 2 weeks. 4. Osteoconduction activity was high in HA+$TGF-{\beta}$ implanted experimental group at 2 and 4 weeks but there was no difference after 6 weeks among 3 groups. 5. In grafted site of HA+$TGF-{\beta}$ implanted group, osteonectin expression was slightly increased from 1 week to 6 weeks. In the host site, it was increased from 1 to 4weeks. 6. In grafted site of HA+$TGF-{\beta}$ implanted group, osteocalcin expression was high at 4 weeks. In the host site, we could find the difference among 3 groups. From above results, the HA with mixture of $TGF-{\beta}$ has the potentiality of promoting bone formation in the bony defect area in the rat.

• Korean Journal of Food Science and Technology
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• v.16 no.3
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• pp.267-272
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• 1984

${\beta}-Fructofuranosidase$ was immobilized covalently on the oxidized microbial wall of a Penicillium spp. 'PS-8', which is totally different from the conventional whole cell immobilization in concept. The immobilization of ${\beta}-fructofuranosidase$ by a series of treatments; oxidation of microbial cells with sodium metaperiodate, enzyme loading on the oxidized cells, extrusion, and crosslinking induced by glutaradehyde, were carried out. The final product had a good mechanical strength and showed 26% of the applied enzyme activity. The specific activity was 750 units per g of the dry cell product. The immobilized enzyme showed the kinetic parameters as follows; optimum pH at 5, optimum temperature at $55^{\circ}C$, activation energy of 19 kJ $mol^{-1}$, and apparent Km of 55 mM.

• The Korean Journal of Food And Nutrition
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• v.35 no.5
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• pp.324-331
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• 2022

Recently, consumers' awareness of the importance of the intestinal action of lactic acid bacteria and intestinal microbes is increasing, as well as interest in yogurt. In this study, yogurt was prepared with three mixed strains (lactic acid bacteria combination, Lactobacillus acidophilus, Lactobacillus delbrueckii subsp., and Bulgaricus, Streptococcus thermophilussei, 1:1:1) by adding oats flour, and the quality characteristics of yogurt were investigated, while stored at a storage temperature of 4℃ for 12 days. According to the storage period, the control as wel as the oat yogurt showed slight decrease in pH, and no significant change in acidity. Sugar content slightly increased. and brightness decreased, in the control and the oat yogurt. Visible cell numbers increased during storage, and decreased on the 12th day. Viscosity in the oat yogurt was 7,580 cP, which was approximately eight times higher than that of the control group, and decreased gradually according to the storage period. Antioxidant activity (DPPH) was approximately two times higher in the oat-added yogurt, and slightly increased with the storage period, decreased on the 12th day of storage, and β-glucan was detected only in oat-added yogurt.

• The Korean Journal of Physiology and Pharmacology
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• v.27 no.3
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• pp.257-265
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• 2023

Kidney ischemia/reperfusion (I/R) injury, a common cause of acute kidney injury (AKI), is associated with the migration of inflammatory cells into the kidney. Ras-related C3 botulinum toxin substrate 1 (Rac1), a member of the Rho family of small GTPase, plays an important role in inflammatory cell migration by cytoskeleton rearrangement. Here, we investigated the role of Rac1 on kidney I/R injury and macrophage migration. Male mice were subjected to either 25 min of bilateral ischemia followed by reperfusion (I/R) or a sham operation. Some mice were administrated with either NSC23766, an inhibitor of Rac1, or 0.9% NaCl (vehicle). Kidney damage and Rac1 activity and expression were measured. The migration and lamellipodia formation of RAW264.7 cells, mouse monocyte/macrophage, induced by monocyte chemoattractant protein-1 (MCP-1, a chemokine) were determined using transwell migration assay and phalloidin staining, respectively. In sham-operated kidneys, Rac1 was expressed in tubular cells and interstitial cells. In I/R-injured kidneys, Rac1 expression was decreased in tubule cells in correlation with the damage of tubular cells, whereas Rac1 expression increased in the interstitium in correlation with an increased population of F4/80 cells, monocytes/macrophages. I/R increased Rac1 activity without changing total Rac1 expression in the whole kidney lysates. NSC23766 administration blocked Rac1 activation and protected the kidney against I/R-induced kidney damage and interstitial F4/80 cell increase. NSC23766 suppressed monocyte MCP-1-induced lamellipodia and filopodia formation and migration of RAW 264.7 cells. These results indicate Rac1 inhibition protects the kidney against I/R via inhibition of monocytes/macrophages migration into the kidney.