• Fire Science and Engineering
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• v.23 no.5
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• pp.24-31
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• 2009

Based on fallen leaves of major Korean conifer species 'Pinus densiflora' and major Korean broadleaved species 'Quercus variabilis', this study sought to identify combustion emission gas types and measure their concentration by means of FTIR (Fourier Transform Infrared) spectrometer. As a result, it was found that there were total 13 types of combustion gas detected from fallen leaves of Pinus densiflora and Quercus variabilis, such as carbon monoxide, carbon dioxide, acetic acid, butyl acetate, ethylene, methane, methanol, nitrogen dioxide, ammonia, hydrogen fluoride, sulfur dioxide and hydrogen bromide. Notably, nitrogen monoxide was additionally detected from fallen leaves of Quercus variabilis. It was found that the overall concentration of combustion gas emitted from the fallen leaves of Pinus densiflora was 4.5 times higher than that from fallen leaves of Quercus variabilis. Particularly, it was found that emission concentration of some combustion emission gas types like carbon monoxide, carbon dioxide and butyl acetate exceeded the upper limit of their time-weighted average (TWA, ppm), while the emission concentration of carbon monoxide and carbon dioxide exceeded their short-term exposure limit (STEL, ppm) for both species. Thus, it was found that carbon monoxide and carbon dioxide have higher hazard to health than other gas types, because these two gas types account for higher than 99% of overall gas emission due to combustion of surface fire starting from litter layer in forest.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.31 no.3
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• pp.255-265
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• 2021

Objectives: The purpose of this study is to analyze the exposure characteristics of inorganic acids. Methods: We analyzed exposure data (n = 363,146) for six inorganic acids (hydrogen fluoride, hydrogen bromide, hydrogen chloride, phosphoric acid, nitric acid, and sulfuric acid) collected between 2017 and 2019 in South Korea. Measurement characteristics and exposure levels (ELs) were analyzed by inorganic acid, industry category, enterprise size, and measurement year. Results: Measurement percentage dominated in time-weighted average (TWA, 91%) compared to short term exposure limit (STEL) and Ceiling. Most of the measurements (79.7%) were collected from the manufacturing category of industry. Medians of ELs were mostly low (≤3% of the threshold limit), with the exception of sulfuric acid (4.6% of TWA and 10.5% of STEL). The percentages of exceeding 1% of the occupational exposure limits (OELs) in TWA were relatively high for sulfuric acid (35.8%) and hydrogen chloride (16.5%) compared to the other acids (4.2%-6.6%). In addition, the percentages of exceeding 1% of OELs in STEL or Ceiling were higher for sulfuric acid (22.9%), hydrogen chloride (12.3%), and nitric acid (8.2%) compared to the other acids (1.2%-1.9%). The small-sized enterprises showed higher ELs in TWA; contrarily, the large-sized enterprises had higher ELs in STEL or Ceiling. Conclusions: The measurement characteristics and ELs identified in this study could be useful for establishing safety and health policies for inorganic acids.

• Analytical Science and Technology
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• v.29 no.2
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• pp.73-78
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• 2016

Hydrogen cyanide (HCN) is an extremely toxic gas frequently produced during the incineration of plastics, such as acrylonitrile-butadiene-styrene (ABS). A victim of a fire who has inhaled smoke could have cyanide in the blood. Therefore, cyanide could be a good marker for a post-mortem examination of a fire as well as carboxyhemoglobine (COHb) test of blood samples. For a particular fire case, a burned body with a suicide note was found inside a burned vehicle. Even though the COHb value is conclusive evidence, measuring the COHb for denatured blood might be difficult due to severe thermal denaturation or the formation of methemoglobin (MetHb). To overcome this difficulty, cyanide could be used as an indicator when investigating the death of a fire victim. In this study, gas chromatography/mass spectrometry (GC/MS) was adopted to measure the levels of cyanide in the blood through derivatization with pentafluorobenzyl bromide (PFBBr) under cation surfactant by scan and SIM mode. The concentration of cyanide in the blood of heart blood and brain of the victim was found to be 0.36 µg/mL and 1.20 µg/mL respectively, which was higher than the average value (0.041 µg/mL) found in the blood of 14 people who smoked.

• Journal of Physiology & Pathology in Korean Medicine
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• v.29 no.5
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• pp.403-408
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• 2015

Traditionally, 5 kinds of fruits with "ja(子)" in their name, including Rubus coreanus, Schisandra chinensis, Lycinum chineuse, Torilidis fructus, and Cuscuta seed, collectively called Oja(五子), are long known to enhance stamina. In the present study, we replaced tosaja with gyeolmyeongja(Cassiae semen ) and examined the effects of extracts from these fruits on andropause. This study investigated the antioxidant effect and testosterone synthesis of Oja water extract on Leydig TM3 cells. To investigate whether hydrogen peroxide induces oxidative stress in Leydig cells, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay, nitric oxide assay, and testosterone assay were performed on mouse Leydig TM3 cells. The results were obtained as follows: Leydig TM3 cells viability was assessed by a modified MTT assay, and the protection effect of Oja water extract against hydrogen peroxide-induced cell oxidative stress were examined by mitochondrial activity. Oja water extract could efficiently protect cytotoxicity induced by H₂O₂. Oja water extract promoted testosterone synthesis. These results suggest that Oja water extract has protective roles and promotes steroidogenesis in Leydig cells through its anti-oxidant action.

• Journal of Hydrogen and New Energy
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• v.27 no.4
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• pp.365-371
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• 2016

Cell performance of the Zn-Br redox flow battery (ZBRFB) using two different type's membrane (Nafion117 and SF-600) was evaluated at $20mA/cm^2$ of current density in 1M (mol/L) $ZnBr_2$ + 2M KCl + 0.3M EMPBr(1-ethyl-1-methyl pyrrolidinium bromide) electrolyte. The average energy efficiencies of ZBRFB were 74.9% and 74.7% for Nafion117 and SF-600, respectively. The electrolyte added the 1-ethyl-3-methylimidazolium dicyanamide (EMICA) as an additive was tested for the electrolyte in ZBRFB using SF-600 at $30mA/cm^2$ of current density. An average energy efficiency of the ZBRFB was 74.5% and 77.4% for the electrolyte non-added EMICA and added 1wt% of EMICA, respectively. ZBRFB using the electrolyte added EMICA was showed the higher performance than that using the electrolyte non-added EMICA.

• Korean Journal of Medicinal Crop Science
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• v.14 no.2
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• pp.70-76
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• 2006

Paeoniae radix has been widely used for its anti-allergic, anti-inflammatory and analgesic effects, and demonstrated to have anticonvulsant, memory enhancing and anxiolytic activities. The present study was performed to examine the protective effect of methanol extract of Paeoniae radix (PR) from Paeoniae Japonica Miyabe et Takeda (Paeoniaceae) on hydrogen peroxide $(H_2O_2)-induced$ neurotoxicity using cultured rat cerebral cortical neuron. $H_2O_2$ produced a concentration-dependent reduction of neuronal viability, PR, over a concentration range of 10 to $100\;{\mu}g/ml$ showed concentration-dependent decrease of the $H_2O_2$$(100\;{\mu}M)-induced$ neuronal cell death, as assessed by a 3-[4,5-dimethylthiazol-2-yl]-2,5-di-phenyl-tetrazolium bromide assay and the number of apoptotic nuclei, evidenced by Hoechst 33342 staining. PR $(100\;{\mu}g/ml$ inhibited $100\;{\mu}M$ $H_2O_2-induced$ elevation of the cytosolic $Ca^{2+}$ concentration $([Ca^{2+}]_c)$, which was measured by a fluorescent dye, flue-4 AM. PR $(50\;{\mu}g/ml$ inhibited glutamate release into medium induced by $100\;{\mu}M$ $H_2O_2$, which was measured by HPLC, and generation of reactive oxygen species (ROS). These results suggest that PR may mitigate the $H_2O_2-induced$ neurotoxiciy by interfering with the increase of $[Ca^{2+}]_c$, and then inhibiting glutamate release and generation of ROS in cultured neurons.

• BMB Reports
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• v.39 no.2
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• pp.145-149
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• 2006

To analyze the effect of Maltol on the apoptosis of Human Neuroblastoma Cells (SH-SY5Y) treated by free radical which was generated from Hydrogen Peroxide ($H_2O_2$), flow cytometry analysis on Phosphatidylserine (PS) inverting percentage was applied to determine the apoptosis. MTT (3-(4,5-dimethythiazol-2-yl)-2,5-diphenyl-tetrazolium bromide) assay was employed to analyze the cell viability. DNA electrophoresis was used to detect DNA fragmentation. Moreover intracellular calcium of concentration ($[Ca^{2+}]_i$) was measured by fluorescence emission. Flow cytometry analysis on the function of mitochondria and Western blto analysis of NF-${\kappa}B$. The results showed that the pretreatment with maltol for 2 hours could prevent the $H_2O_2$-induced apoptosis. Maltol could reduce the inverting percentage of PS, DNA fragmentation and $[Ca^{2+}]_i$, and enhance the cellular function of mitochondria. NF-${\kappa}B$ activated by $H_2O_2$ is reduced. The experiments suggest that maltol could effectively inhibit the apoptosis induced by $H_2O_2$. As a novel anti-oxidant, maltol is a new promising drug in protecting the neurological cells from the damage by free radical.

• Korean Journal of Medicinal Crop Science
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• v.15 no.2
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• pp.105-111
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• 2007

The protective effect of ethanol extract of Korean mistletoe (KM; Viscum album coloratum) on hydrogen peroxide $(H_{2}O_{2})-induced$ neurotoxicity was examined in primary cultured rat cortical neurons. $H_{2}O_{2}$ reduced viability of cortical neurons in a concentration-dependent manner. The addition of KM, over a concentration range of 10 to 100 ${\mu}g/ml$, concentration-dependently prevented the $H_{2}O_{2}(100\;{\mu}M)-induced$ neuronal cell death, as assessed by a 3-[4,5-dimethylthiazol-2-yl]-2,5-di-phenyl-tetrazolium bromide (MTT) assay and Hoechst 33342 staining. KM significantly inhibited $H_{2}O_{2}-induced$ elevation of the cytosolic $Ca^{2+}$ concentration $([Ca^{2+}]_{c})$, which was measured by a fluorescent dye, fluo-4 AM. KM inhibited glutamate release into medium and generation of reactive oxygen species (ROS) induced by $H_{2}O_{2}$. These results suggest that KM may mitigate the $H_{2}O_{2}-induced$ neurotoxiciy by interfering with the increase of $[Ca^{2+}]_{c}$, and inhibiting glutamate release and generation of ROS in cultured neurons.

• Advances in Traditional Medicine
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• v.2 no.1
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• pp.36-40
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• 2002

Effects of hydrogen peroxide $(H_2O_2)-induced$ neurotoxicity were investigated in cultured newborn rat spinal dorsal root ganglion (DRG) neurons after DRG neurons were treated in the media containning various concentrations of $H_2O_2$. In addition, the protective effect of Herba Epimedii (HE) extract against $H_2O_2-induced$ neurotoxicity was examined. Cytotoxic values were determined by the cell viability of living cells using 3-(4,5-dimethylthiazol-2-yl) -2,5-diphenyltetrazolium bromide (MTT) assay. In the present study, exposure of neurons to $H_2O_2$ resulted in a significant cell death in a dose- and time-dependent manners in cultured DRG neurons. The decrement of cell viability by $H_2O_2$ was blocked by HE. These results suggest that the neuroprotective effect of HE against $H_2O_2-induced$ cytotoxicity may result from the prevention of injury induced by $H_2O_2$.

• Korean Journal of Medicinal Crop Science
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• v.17 no.1
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• pp.68-74
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• 2009

Vitis amurensis (VA; Vitaceae) has long been used in oriental herbal medicine. It has been reported that roots and seeds of VA have anti-inflammatory and antioxidant effects. In the present study, the protective effect of ethanol extract from stems and leaves of VA on hydrogen peroxide (${H_2}{O_2}$) (100 ${\mu}M$)-induced neuronal cell damage was examined in primary cultured rat cortical neurons. VA (10-100 ${\mu}g$/ml) concentration-dependently inhibited ${H_2}{O_2}$-induced apoptotic neuronal cell death measured by 3-[4,5-Dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) assay and Hoechst 33342 staining. VA inhibited ${H_2}{O_2}$-induced elevation of intracellular $Ca^{2+}$ concentration (${[Ca^{2+}]}_i$) and generation of reactive oxygen species (ROS), which were measured by fluorescent dyes. Pretreatment of VA also prevented glutamate release into medium induced by 100 ${\mu}M$ ${H_2}{O_2}$, which was measured by HPLC. These results suggest that VA showed a neuroprotective effect on ${H_2}{O_2}$-induced neuronal cell death by interfering with ${H_2}{O_2}$-induced elevation of ${[Ca^{2+}]}_i$, glutamate release, and ROS generation. This has a significant meaning of finding a new pharmacological activity of stems and leaves of VA in the CNS.