• Journal of The Korean Association For Science Education
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• v.18 no.3
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• pp.303-312
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• 1998

In this study, the multimedia CAl program for chemical equilibrium in high school grade 3 was developed and the effect of CAl on achievement and attitude toward chemistry instruction and computer was investigated. Before instruction, the test of attitudes toward chemistry instruction and computer were administered, and the grade in the mid-term examination was obtained. These scores were used as covariates. Mid-term science score was used as blocking variable. For chemical equilibrium instruction, traditional and computer assisted instruction were used. After instruction, the achievement test and the test of attitudes toward science instruction and computer were administered. The results indicated that students in the treatment group achieved significantly better than those in the control group, but did not show improvement of attitude to chemistry instruction and computer compared to those in the control group. No significant interaction between the treatment and the level of students' prior achievement was found. Female achieved significantly better under CAl than under traditional instruction. In two subtests(understanding and application), treatment group achieved better in the subtest of application than control group. CAl had an effect on chemical equilibrium state (about reversibility) significantly. While female of the treatment group did not show more positive attitude toward both chemistry instruction and computer significantly than that of the control group, male showed more positive attitude significantly. Educational implications are discussed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.11
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• pp.1507-1511
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• 2011

This study investigated the anti-inflammatory effect of Erigeron annuus L. flower (EAF) methanol extract. We examined the involvement of heme oxygenase-1 (HO-1) in the inhibitory activities of EAF methanol extract on nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated RAW264.7 macrophages. Cell viability and NO assays were performed. In addition, inducible nitric oxide synthase (iNOS) and HO-1 expressions were detected by Western blotting and blocking HO-1 activity on NO production. EAF methanol extract (25, 50, 100, 200 ${\mu}g$/mL) significantly inhibited LPS-stimulated NO production (p<0.05; 12.82, 9.61, 6.83, 2.52 ${\mu}m$) in a concentration-dependent manner. EAF methanol extract also reduced the expression of iNOS protein. The EAF methanol extract induced the expression of HO-1 in a dose-dependent manner. Blockage of HO-1 activity by zinc protoporphyrin suppressed EAF methanol extract-induced reductions in the production of NO. The present results suggest that EAF methanol extract has a potent anti-inflammatory effect in RAW264.7 macrophages through the induction of HO-1.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.6
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• pp.1500-1508
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• 2003

This study was performed to clarify the neurotoxic mechanism of nerve cells damage by brain ischemia. The cytotoxic effect of ischemia was determined by XTT assay, NR assay, superoxide dismutase(SOD) activity, amount of malondialdehyde(MDA), lactate dehydrogenase(LDH) activity, protein synthesis and tumor necrosis factor(TNF)-α activities after cerebral neurons derived from mouse were exposed to ischemia for 1∼30 minutes. In addition, the protective effect of extract of Daejo-whan(DJW) on ischemia-induced neurotoxicity was examined in these cultures. 1. Ischemia decreased cell number and viability by XTT assay or NR assay when cultured cerebral neurons were exposed to 95% N2/5% CO₂ for 1∼20 minutes in these cultures. 2. Ischemia decreased SOD and protein syntheses, but it increased amount of MDA and, LDH and TNF-α activities in these cultures. 3. In the neuroprotective effect of DJW extracts on cerebral neurons damaged by ischemia, DJW extracts increased SOD activity and protein synthesis. While, it decreased amount of MDA and, LDH and TNF-α activities after cerebral neurons preincubated with herb extracts. It suggests that brain ischemia has neurotoxicity on cultured mouse cerebral neurons, and the herb extract such as DJW was very effective in blocking the neurotoxicity induced by ischemia in cultured mouse cerebral neurons.

• The Korean Journal of Pharmacology
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• v.30 no.1
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• pp.101-109
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• 1994

Pharmacological characterization of GS 283, a tetrahydroisoquinoline derivative has been elucidated using rat thoracic aorta, guinea pig tenea coli and rabbit mesentery artery in vitro. GS 283 showed calcium antagonistic action in vascular smooth muscle, since high $K^+-induced$ contraction was concentration dependently inhibited. GS 283 also inhibited the contraction induced by ${\alpha}_1$ receptor activation. Vasodilating action of GS 283 was not modified by the propranolol, indicating that GS 283 has no ${\beta}$ receptor stimulatory action. Simultaneous measurement of intracellular calcium change and muscle tension indicated that the inhibitory effect of GS 283 was accompanied by the increase in tissue fluorescence. This increment was not due to fura 2 fluorescence but to endogenous pyridine nucleotide, suggesting that GS 283 has an effect to inhibit mitochondrial function. GS 283 had an inhibitory action on cyclic AMP and GMP-dependent phosphodiesterases from rat brain with Ki values of 2.5 and 6.7 mM. From these findings we concluded that GS 283 has multiple action such as the inhibition of cyclic nucleotide-dependent phosphodiesterases, blocking of calcium channel as well as inhibition of mitochondrial function which are responsible for vasodilatation.

• The Journal of Korean Medicine
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• v.27 no.3 s.67
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• pp.107-131
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• 2006

Background and Aims: Dansamtongmek-tang (DSTMT) and Dansamsengmek-san (DSSMS) have been used for many years as therapeutic agents for the acute stage of cerebrovascular disease, hypertension and hyperlipidemia in Oriental medicine, but the effects of DSTMT and DSSMS on hyperlipidemia and safety for cell damage are not yet well-known. This study was done to investigate the effects of DSTMT and DSSMS on hyperlipidemia. Methods: In vivo test: after administering DSTMT and DSSMS to SHR and ICR occurred hyperlipidemia for 3 weeks, we analyzed body weight, cholesterol levels. TG, HDL-chol, LDL-chol, LDH in plasma, brain, liver and kidney tissue, and DNA by RT-PCR. In vitro test: after administering DSTMT and DSSMS to human hepatocellular carcinoma in hypoxia, we observed cell cohesion by light microscope, analyzed the inflow of Ca2+ by confocal laser scanning microscope and DNA by RT-PCR. Results: DSTMT significantly decreased the levels of triglyceride and increased the levels of HDL-cholesterol in SHR, and significantly decreased the levels of LDL-cholesterol and body weight and increased the levels of HDL-cholesterol in ICR. DSSMS significantly decreased body weight, total cholesterol levels, LDL-cholesterol, LDH and cardiac risk factor (CRE) in SHR and significantly decreased the levels of total cholesterol, triglyceride, LDL-cholesterol, LDH and CRF in ICR. DSTMT had an effect on protecting cells from damage by inhibiting production of p53 mRNA, and in DSSMS, by inhibiting production of p53 mRNA and p21 mRNA after hypoxia. DSTMT effectively blocked off Ca2+ at low density, but DSSMS effectively blocked off Ca2+ at high density. Both DSTMT and DSSMS had an effect on inhibiting lipid metabolism by blocking off production of apo B mRNA. Conclusions: These results suggest that DSTMT and DSSMS might be usefully applied for treatment of hyperlipidemia and suppression of brain damage.

• Journal of Ginseng Research
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• v.40 no.2
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• pp.135-140
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• 2016

Background: Nephrotoxicity is a common side effect of medications. Panax ginseng is one of the best-known herbal medicines, and its individual constituents enhance renal function. Identification of its efficacy and mechanisms of action against drug-induced nephrotoxicity, as well as the specific constituents mediating this effect, have recently emerged as an interesting research area focusing on the kidney protective efficacy of P. ginseng. Methods: The present study investigated the kidney protective effect of fermented black ginseng (FBG) and its active component ginsenoside 20(S)-Rg3 against cisplatin (chemotherapy drug)-induced damage in pig kidney (LLC-PK1) cells. It focused on assessing the role of mitogen-activated protein kinases as important mechanistic elements in kidney protection. Results: The reduced cell viability induced by cisplatin was significantly recovered with FBG extract and ginsenoside 20(S)-Rg3 dose-dependently. The cisplatin-induced elevated protein levels of phosphorylated c-Jun N-terminal kinase (JNK), p53, and cleaved caspase-3 were decreased after cotreatment with FBG extract or ginsenoside 20(S)-Rg3. The elevated percentage of apoptotic LLC-PK1 cells induced by cisplatin treatment was significantly abrogated by cotreatment with FBG and the ginsenoside 20(S)-Rg3. Conclusion: FBG and its major ginsenoside 20(S)-Rg3, ameliorated cisplatin-induced nephrotoxicity in LLC-PK1 cells by blocking the JNKep53ecaspase-3 signaling cascade.

• Journal of the Korean Applied Science and Technology
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• v.37 no.5
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• pp.1138-1150
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• 2020

In this study, an experiment was conducted to develop a sunscreen with antioxidant effects by simultaneously investigating the antioxidant and UV protection capabilities of various plant extracts. First, to investigate the UV-blocking ability of 33 kinds of plant extracts, the absorbance spectrum between the UV wavelength of 280 to 400 nm was investigated. Arrowroot, graviola, wheat sprout, sangbaek skin, thorn meal, lacquer, etc. 11 species were selected. The total polyphenol content, total flavonoid content, and DPPH radical scavenging activity of the selected plant extracts are measured to examine the degree of antioxidant activity, and from this, it is a plant extract that has excellent UV protection and antioxidant activity at the same time. The species was selected. A gel-shaped cream is prepared by mixing the selected gold, hops, and licorice extracts in a ratio of 1:1:1, and the UV protection effect of this cream is measured when the cultured cells are irradiated with UV rays. Determined by the method. As a result of the study, it was confirmed that the selected mixture of plant extracts complemented each other in terms of ultraviolet absorption ability and increased cell damage protection effect. Through these results, it was confirmed that it was possible to develop a sunscreen with an antioxidant effect if the antioxidant and sunscreen capabilities of various plant extracts were determined at the same time.

• The Korean Journal of Physiology and Pharmacology
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• v.12 no.3
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• pp.101-109
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• 2008

The aim of the present study was to examine the effects of ketamine, a dissociative anesthetics, on secretion of catecholamines (CA) secretion evoked by cholinergic stimulation from the perfused model of the isolated rat adrenal gland, and to establish its mechanism of action, and to compare ketamine effect with that of thiopental sodium, which is one of intravenous barbiturate anesthetics. Ketamine ($30{\sim}300{\mu}M$), perfused into an adrenal vein for 60 min, dose- and time-dependently inhibited the CA secretory responses evoked by ACh (5.32 mM), high $K^+$ (a direct membrane-depolarizer, 56 mM), DMPP (a selective neuronal nicotinic NN receptor agonist, $100{\mu}M$) and McN-A-343 (a selective muscarinic M1 receptor agonist, $100{\mu}M$). Also, in the presence of ketamine ($100{\mu}M$), the CA secretory responses evoked by veratridine (a voltage-dependent $Na^+$ channel activator, $100{\mu}M$), Bay-K-8644 (an L-type dihydropyridine $Ca^{2+}$ channel activator, $10{\mu}M$), and cyclopiazonic acid (a cytoplasmic $Ca^{2+}$-ATPase inhibitor, $10{\mu}M$) were significantly reduced, respectively. Interestingly, thiopental sodium ($100{\mu}M$) also caused the inhibitory effects on the CA secretory responses evoked by ACh, high $K^+$, DMPP, McN-A-343, veratridine, Bay-K-8644, and cyclopiazonic acid. Collectively, these experimental results demonstrate that ketamine inhibits the CA secretion evoked by stimulation of cholinergic (both nicotinic and muscarinic) receptors and the membrane depolarization from the isolated perfused rat adrenal gland. It seems likely that the inhibitory effect of ketamine is mediated by blocking the influx of both $Ca^{2+}$ and $Na^+$ through voltage-dependent $Ca^{2+}$ and $Na^+$ channels into the rat adrenal medullary chromaffin cells as well as by inhibiting $Ca^{2+}$ release from the cytoplasmic calcium store, which are relevant to the blockade of cholinergic receptors. It is also thought that, on the basis of concentrations, ketamine causes similar inhibitory effect with thiopental in the CA secretion from the perfused rat adrenal medulla.

• Journal of Sasang Constitutional Medicine
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• v.15 no.1
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• pp.72-89
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• 2003

To elucidate the neuroprotective effect of Yeoldahanso-tang(YHT) on nerve cells damaged by hypoxia, the cytotoxic effects of exposure to hypoxia were determined by XTT(SODIUM3,3'-{I-[(PHENYLAMINO) CARBONYL]-3,4-TETRAZOLIUM}- BIS (4-METHOXY-6-NITRO) BENZENE SULFONIC ACID HYDRATE), NR(Neutral red), MTT(3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and SRB(Sulforhodamin B) asssay. The activity of catalase and SOD(Superoxide dismutase) was measured by spectrophometry, and $TNF-{\alpha}$(Tumor cell necrosis $fector-{\alpha}$) and PKC(Protein kinase C) activity was measured after exposure to hypoxia and treatment of YHTWE. Also the neuroprotective effect of YHTWE was researched for the elucidatioion of neuroprotective mechanism. The results were as follows; 1. Hypoxia decreased cell viability measured by XTT, NR assay when cultured cerebral neurons were exposed to 95% N2/5% CO2 for $2{\sim}26$ minutes in these cultures and YHTWE inhibited the decrease of cell viability. 2. H2O2 treatment decreased cell viability measured by MTT, and SRB assay when cultured cerebral neurons were exposed to 1-80 ${\mu}M$ for 6 hours, but YHTWE inhibited the decrease of cell viability. 3. Hypoxia decreased catalase and SOD activity, and also $TNF-{\alpha}$ and PKC activity in these cultured cerebral neurons, but YHTWE inhibited the decrease of the catalase and SOD activity in these cultures. 4. Hypoxia triggered the apoptosis via caspase activation and internucleosomal DNA fragmentation. Also hypoxia stimulate the release of cytochrome c forom mitochondria. YHTWE inhibited the apoptosis via caspase activation induced by hypoxia. From these results, it can be suggested that brain ischemia model induced hypoxia showed neurotoxicity on cultured mouse cerebral neurons, and the YHTWE has the neuroprotective effect in blocking the neurotoxicity induced by hypoxia in cultured mouse cerebral neurons.

• Journal of Ginseng Research
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• v.42 no.3
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• pp.389-399
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• 2018

Background: The antioxidant effects of Panax ginseng have been reported in several articles; however, little is known about the antimelanogenesis effect, skin-protective effect, and cellular mechanism of Panax ginseng, especially of P. ginseng calyx. To understand how an ethanol extract of P. ginseng berry calyx (Pg-C-EE) exerts skin-protective effects, we studied its activities in activated melanocytes and reactive oxygen species (ROS)-induced keratinocytes. Methods: To confirm the antimelanogenesis effect of Pg-C-EE, we analyzed melanin synthesis and secretion and messenger RNA and protein expression levels of related genes. Ultraviolet B (UVB) and hydrogen peroxide ($H_2O_2$) were used to induce cell damage by ROS generation. To examine whether this damage is inhibited by Pg-C-EE, we performed cell viability assays and gene expression and transcriptional activation analyses. Results: Pg-C-EE inhibited melanin synthesis and secretion by blocking activator protein 1 regulatory enzymes such as p38, extracellular signal-regulated kinases (ERKs), and cyclic adenosine mono-phosphate response element-binding protein. Pg-C-EE also suppressed ROS generation induced by $H_2O_2$ and UVB. Treatment with Pg-C-EE decreased the expression of matrix metalloproteinases, mitogen-activated protein kinases, and hyaluronidases and increased the cell survival rate. Conclusion: These results suggest that Pg-C-EE may have antimelanogenesis properties and skin-protective properties through regulation of activator protein 1 and cyclic adenosine monophosphate response element-binding protein signaling. Pg-C-EE may be used as a skin-improving agent, with moisture retention and whitening effects.