• YAKHAK HOEJI
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• v.32 no.5
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• pp.343-350
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• 1988

Recent hypothesis suggested that intracellular accumulation of calcium is a common denominator of ischemic celullar damage. Flunarizine, a calcium entry blocker, posses vasodilating properties in cerebral vascular beds and clinically used in circulatory disorders. The present study was designed to evaluate the effect of flunarizine on ischemic and hypoxic brain damage. An ischemic model was made by bilateral carotid artery ligation (BCAL) in Wistar strain rat. Hypoxic model was made by intravenous injection(i.v.) of KCN to rats and mice. In mice, flunarizine not only reduced the mortality of KCN, but also delayed the onset time of convulsion. The contents of ATP, creatine phosphate and glucose, cerebral energy metabolite, decreased 30 minutes after BCAL and KCN i, v, while that of lactate increased. But these variations were suppressed by flunarizine. Furthermore, increase in the dosage of flunarizne generally promoted the recovery of cerebral energy metabolites in hypoxic animals. The results suggest that flunarizine had a protective effect against ischemic and hypoxic brain damage due to its ameliorating action on the cerebral energy metabolism.

• Journal of the Korean institute of surface engineering
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• v.49 no.4
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• pp.349-356
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• 2016

In this study, electrochemical damage behaviors with flow rate were investigated for anodized 5083 aluminum alloy in seawater. As the results of anodic polarization experiments and potentiostatic experiments at +1.0 V (vs. SSCE), the non-flow condition presented largely damaged surface resulting from a tendency of local pitting damage. Under various flow rate conditions, however, less surface damages under the application of anodic potential was obtained which is attributed to no accumulation of $H^+$ and $Cl^-$ ions on the surface. On the other hand, the results of the potentiostatic experiments at -1.0 V (vs. SSCE) with flow rate showed that anodized 5083 aluminum alloys could achieve the effective cathodic protection by low cathodic protection current density less than $2.61{\times}10^{-7}A/cm^2$ even under high flow rate of 1 m/s.

• Korean Journal of Agricultural Science
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• v.43 no.4
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• pp.522-536
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• 2016

Fluorine is unique chemical element which occurs naturally, but is not an essential nutrient for plants. Fluoride toxicity can arise due to excessive fluoride intake from a variety of natural or manmade sources. Fluoride is phytotoxic to most plants. Plants which are sensitive for fluorine exposure even low concentrations of fluorine can cause leave damage and a decline in growth. All vegetation contains some fluoride absorbed from soil and water. The highest levels of F in field-grown vegetables are found up to $40mg\;kg^{-1}$ fresh weight although fluoride is relatively immobile and is not easily leached in soil because most of the fluoride was not readily soluble or exchangeable. Also, high concentrations of fluoride primarily associated with the soil colloid or clay fraction can increase fluoride levels in soil solution, increasing uptake via the plant root. In soils more than 90 percent of the natural fluoride ranging from 20 to $1,000{\mu}g\;g^{-1}$ is insoluble, or tightly bound to soil particles. The excess accumulation of fluorides in vegetation leads to visible leaf injury, damage to fruits, changes in the yield. The amount of fluoride taken up by plants depending on the type of plant, the nature of the soil, and the amount and form of fluoride in the soil should be controlled. Conclusively, fluoride is possible and long-term pollution effects on plant growth through accumulation of the fluoride retained in the soil.

• The Korean Journal of Nuclear Medicine
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• v.37 no.3
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• pp.202-205
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• 2003

A 10 days old male infant with congenital megacalyces and megaureter, diagnosed by prenatal ultrasonographic screening, underwent Tc-99m DTPA renal scan for evaluation of urinary tract patency, Tc-99m DMSA scan for evaluation of renal cortical damage. He also underwent intravenous urography(IVU) and renal ultrasonography. Tc-99m DTPA renal scan demonstrates intense tracer accumulation in enlarged both renal pelvocalyses and ureters, which rapidly washout without diuretics administration. Tc-99m DMSA renal cortical scan shows no remarkable photon defect in both renal cortices and visible tracer uptake in both megaureter areas. Ultasonographic and IVU studios show enlarged both renal calyses and bullously dilated ureters, but no dilatation in renal pelvis. Follow up Tc-99m DTPA renal scan, peformed at one year later, also reveals intense tracer accumulation in enlarged both urinary tracts which rapidly washout without diuretics, and shows no significant change compare to the previous Tc-99m DTPA renal scan. Urinary tract obstruction and renal cortical damage can be easily evaluated with Tc-99m DTPA and Tc-99m DMSA scans in patiens with megacalyces and megaureter.

• Journal of the East Asian Society of Dietary Life
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• v.13 no.4
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• pp.293-304
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• 2003

This study was performed to investigate the effects of peking-duck extracts added with medicinal herbs(DJ) on the intoxication of heavy metals (Hg, Pb, Cd, As) in rats. Sprague-Dawley rats weighing 150$\pm$15g, were randomly assigned to groups: basal diet only in normal control group(NCG): basal diet and heavy metals without DJ injection in heavy metal control group(HMC); basal diet, heavy metals and DJ(3mg/ml) injection in heavy metal low duck-juice group(HMLD), basal diet, heavy metals and DJ(30mg/ml) injection in heavy metal middle duck-juice group(HMMD): basal diet, heavy metal and DJ(300mg/ml) injection in heavy metal high duck-juice group(HMHD). Hg and As was injected by 50ppm and Cd and Pb by 25ppm for 17days. Also DJ oral feeding was conducted for 28days. The result of this study were as follows: Food intake and body weight gain in heavy metal administered groups were lower than those of NCG. Liver, kidney and testis weights were not significantly different among 5 groups. GOT, GPT and BUN activities were significantly reduced in DJ treated groups as compared to HMC. DJ showed the suppressing effect on the accumulation of Hg, Pb and Cd in serum, liver and kidney. Fecal Hg and Cd excretions increased with DJ feeding. The results suggested that DJ may have some protective effects on Hg, Cd and Pb intoxication by reducing the accumulation in tissues and increasing excretion. This study also showed the effective way of using duck-extract and its application to the oriental medicine.

• Journal of the Korean Institute of Gas
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• v.11 no.4
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• pp.64-72
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• 2007

Under the AE methods, the valid condition analysis and evaluation the leak etc, resulted by the AE signal pattern on the bottom plate of ground tank at full. In next more, the gradient of accumulation amplitude distribution analysis and comparison the energy, count, and duration time that noise of EMI signal were removed. EMI signal showed height-energy, count, and duration time, it also appeared great gradient of accumulation distribution. Then, with the pure remaining AE signals cluster analysis and location. It would possibly assume of damage with corrosion. Total cluster 20 and energy showed between the maximum 11,990 and 8,565 which is much lower than above figure and event number showed from 8 to 5. Even when it difficult to certify damage by open, as it is raised higher height-sensitivity and threshold by 60 dB. It would possibly presume of location source more accurately.

• Korean Journal of Pharmacognosy
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• v.42 no.3
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• pp.276-281
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• 2011

Oxidative stress or the accumulation of reactive oxygen species (ROS) leads neuronal cellular death and dysfunction, and it contributes to neuronal degenerative disease such as Alzheimer's disease, Parkinson's disease and stroke. Glutamate-induced oxidative injury contributes to neuronal degeneration in many central nervous system (CNS) diseases, such as epilepsy and ischemia. Heme oxygenase-1 (HO-1) enzyme plays an important role of cellular antioxidant system against oxidant injury. The expression of HO-1 has cytoprotective effects in glutamate-induced oxidative cytotoxicity in HT22 cells. The induction of HO-1 is primarily regulated at the transcriptional level, and its induction by various inducers is related to the nuclear transcription factor-E2-related factor 2 (Nrf2). Nrf2 is a master regulator of the antioxidant response. NNMBS008, the water-insoluble fraction of the 70% EtOH extract of roots of Sophora flavescens, showed dominant neuroprotective effects on glutamate-induced neurotoxicity in mouse hippocampal HT22 cells by induced the expression of HO-1 and increased HO activity. In mouse hippocampal HT22 cells, NNMBS008 makes the nuclear accumulation of Nrf2 pathway. In conclusion, the waterinsoluble fraction of the 70% EtOH extract of roots of S. flavescens (NNMBS008) significantly protect glutamate-induced oxidative damage by induction of HO-1 via Nrf2 pathway in mouse hippocampal HT22 cells. These results suggest that these extracts could be the effective candidates for the treatment of ROS-related neurological diseases.

• Natural Product Sciences
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• v.27 no.3
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• pp.201-207
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• 2021

We have previously reported that Acer tegmentosum extract, which is traditionally used in Korea to reduce alcohol-related liver injury, suppresses liver inflammation caused by excessive alcohol consumption and might improve metabolism. The active ingredient, 6-O-galloylsalidroside (GAL), was isolated from A. tegmentosum, and we hypothesized that GAL could provide desirable pharmacological benefits by ameliorating physiological conditions caused by alcohol abuse. Therefore, this study focused on whether GAL could ameliorate alcoholic fat accumulation and repair liver injury in mice. During chronic alcohol consumption plus binge feeding in mice, GAL was administered orally once per day for 11 days. Intrahepatic lipid accumulation was measured in vivo using a noninvasive method, ¹H magnetic resonance imaging, and confirmed by staining with hematoxylin and eosin and Oil Red O. The serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured using a Konelab system, and the triglyceride content was measured in liver homogenates using an enzymatic peroxide assay. The results suggested that GAL alleviated alcohol-induced steatosis,e as indicated by decreased hepatic and serum triglyceride levels in ethanol-fed mice. GAL treatment also correlated with a decrease in the Cd36 mRNA expression, thus potentially inhibiting the development of alcoholic steatosis via the hepatic de novo lipogenesis pathway. Furthermore, treatment with GAL inhibited the expression of cytochrome P450 2E1 and attenuated hepatocellular damage, as reflected by a reduction in ALT and AST levels. These findings suggest that GAL extracted from A. tegmentosum has the potential to serve as a bioactive agent for the treatment of alcoholic fatty liver and liver damage.

• Particle and aerosol research
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• v.19 no.3
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• pp.63-76
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• 2023

An electrostatic precipitator (ESP) has a low pressure drop and a high collection efficiency but its collection efficiency can be reduced due to dust accumulation on the collection plates during long-term operations. In order to maintain the initial dust collection efficiency, it is necessary to periodically clean the collection plates. The common cleaning methods are using physical impacts or water sprays. These cleaning methods can lead to damage to the collection plate or generate wastewater. Herein, we implemented an electrodynamic screen (EDS) for ESP cleaning and evaluated its surface cleaning performance of particles. The EDS is an electrostatic system that can electrostatically repel particles on surfaces, allowing it to clean the ESP without causing damage and wastewater generation. Our evaluation included the analysis of the effects of AC voltage characteristics, electrode configuration and environmental conditions on the cleaning performance of the EDS with the aim of achieving effective surface cleaning. It has been demonstrated that activating the EDS cleans up to 65% of the particles on the surface, which indicates about 94% of our target cleaning zone.

• ALGAE
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• v.35 no.3
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• pp.253-262
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• 2020

Haematococcus pluvialis is a commercial microalga that can produce high quantities of astaxanthin. Under induced conditions, some important changes in the subcellular structures related to astaxanthin accumulation were observable. For example, a large number of astaxanthin granules, oil structures and starch granules appeared in the thick-walled cells; Astaxanthin granules gradually dissolved into the oil structures and spread throughout the entire cell with the fusion and diffusion process of oil structures during the middle and late stages of induction; The plastoglobules were closed to the newly formed structures, and some plastoglobules would abnormally increase in size under stress. Based on observations of cell damage, the degradation of membrane structures, such as chloroplasts, was found to be the primary form of damage during the early stage of induction. During the middle stage of induction, some transparent holes were exposed in the dissolving astaxanthin granules in the cytoplasm. In thick-walled cells, these transparent holes were covered by oil substances dissolving astaxanthin, thereby avoiding further damage to cells. Given the relatively few oil structures, in non-thick-walled cells, the transparent holes expanded to form multiple transparent areas, eventually resulting in the rupture and death of cells. These results suggested that the high level of synthesis and the wide range diffusion of oil explained the expansion of astaxanthin in H. pluvialis.