• Environmental Engineering Research
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• v.20 no.3
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• pp.260-267
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• 2015

The $PM_{10}$, $SO_2$ and $NO_2$ mass concentrations were obtained over five years from monitoring stations across Nanchong, a southwest city in China. Changes in urban air quality over time, as well as the factors influencing that change, were evaluated based on air pollutant concentrations, the Air Pollution Index (API), and the Comprehensive Pollution Index (P). The results showed that the total annual mean $PM_{10}$, $SO_2$ and $NO_2$ concentrations over the five years studied were $61.1{\pm}1.1$, $45.0{\pm}3.9$ and $34.9{\pm}4.9{\mu}g{\cdot}m^{-3}$, respectively. The annual mean concentrations displayed a generally decreasing trend; lower than the annual mean second-level air quality limit. Meanwhile, the annual mean API values were in a small range of 52-53, the air quality levels were grade II, and P values were 1.06-1.21 less than the slight level ($P{\leq}1.31$). Total monthly mean $PM_{10}$, $SO_2$, $NO_2$ concentrations, and API and P values were consistently higher in winter and spring than during autumn and summer. The results of a correlation analysis showed that temperature and pressure were the major meteorological factors influencing pollution levels. Pollution sources included industrial coal and straw burning, automobiles exhaust and road dust, fireworks, and dust storms.

• Environmental Analysis Health and Toxicology
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• v.31
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• pp.11.1-11.6
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• 2016

Objectives A hazard assessment of di(2-ethylhexyl) phthalate (DEHP), a commonly used workplace chemical, was conducted in order to protect the occupational health of workers. A literature review, consisting of both domestic and international references, examined the chemical management system, working environment, level of exposure, and possible associated risks. This information may be utilized in the future to determine appropriate exposure levels in working environments. Methods Hazard assessment was performed using chemical hazard information obtained from international agencies, such as Organization for Economic Cooperation and Development-generated Screening Information Data Set and International Program on Chemical Safety. Information was obtained from surveys conducted by the Minister of Employment and Labor ("Survey on the work environment") and by the Ministry of Environment ("Survey on the circulation amount of chemicals"). Risk was determined according to exposure in workplaces and chemical hazard. Results In 229 workplaces over the country, 831 tons of DEHP have been used as plasticizers, insecticides, and ink solvent. Calculated 50% lethal dose values ranged from 14.2 to 50 g/kg, as determined via acute toxicity testing in rodents. Chronic carcinogenicity tests revealed cases of lung and liver degeneration, shrinkage of the testes, and liver cancer. The no-observed-adverse-effect level and the lowest-observed-adverse-effect level were determined to be 28.9 g/kg and 146.6 g/kg, respectively. The working environment assessment revealed the maximum exposure level to be $0.990mg/m^3$, as compared to the threshold exposure level of $5mg/m^3$. The relative risk of chronic toxicity and reproductive toxicity were 0.264 and 0.330, respectively, while the risk of carcinogenicity was 1.3, which is higher than the accepted safety value of one. Conclusions DEHP was identified as a carcinogen, and may be dangerous even at concentrations lower than the occupational exposure limit. Therefore, we suggest management of working environments, with exposure levels below $5mg/m^3$ and all workers utilizing local exhaust ventilation and respiratory protection when handling DEHP.

• Natural Product Sciences
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• v.10 no.6
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• pp.289-295
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• 2004

Myristica fragrans seed from Myristica fragrans Houtt (Myristicaceae) has various pharmacological activities peripherally and centrally. The present study aims to investigate the effect of the methanol extract of Myristica fragrans seed (MF) on N-methyl-D-aspartate (NMDA)-induced neurotoxicity in primary cultured rat cerebellar granule neuron. MF, over a concentration range of 0.05 to $5\;{\mu}g/ml$, inhibited NMDA (1 mM)- induced neuronal cell death, which was measured by trypan blue exclusion test and 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) assay. MF $(0.5\;{\mu}g/ml)$ inhibited glutamate release into medium induced by NMDA (1 mM), which was measured by HPLC. Pretreatrnent of MF $(0.5\;{\mu}g/ml)$ inhibited NMDA (1 mM)-induced elevation of cytosolic calcium concentration $([Ca^{2+}]_c)$, which was measured by a fluorescent dye, Fura 2-AM, and generation of reactive oxygen species (ROS). These results suggest that MF prevents NMDA-induced neuronal cell damage in vitro.

• Korean Journal of Medicinal Crop Science
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• v.13 no.2
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• pp.95-102
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• 2005

Caulis Bambusae in Taenia is widely used in Korea and China due to its various pharmacological activity. The present study aims to investigate the effect of the methanol extract of Caulis Bambusae in Taenia (CB) from Phyllostachys nigra Munro var. henonis Stapf (Gramineae) on amyloid ${\beta}$ protein (25-35) $(A{\beta}\;(25-35))$, a synthetic 25-35 amyloid peptide, -induced neurotoxicity using cultured rat cortical neurons. CB, over a concentration range of $10-50{\mu}g/{\mu}l$, inhibited the $A{\beta}\;(25-35)\;(10\;{\mu}M)$-induced neuronal cell death, as assessed by a 3-[4,5-dimethyIthiazole-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) assay and the number of apoptotic nuclei, evidenced by Hoechst 33342 staining. CB $(50\;{\mu}g/{\mu}l)$ inhibited glutamate release into medium induced by $10\;{\mu}M\;A{\beta}$, (25-35) which was measured by HPLC. Pretreatment of CB $(50\;{\mu}g/{\mu}l)$ inhibited $10{\mu}M\;A{\beta}$ (25-35)-induced elevation of cytosolic calcium concentration $([Ca^{2+}]_c)$, which was measured by a fluorescent dye, fluo-4 AM, and generation of reactive oxygen species. These results suggest that CB prevents $A{\beta}$ (25-35)-induced neuronal ell damage in vitro.

• International Journal of Industrial Entomology and Biomaterials
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• v.14 no.2
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• pp.107-112
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• 2007

The mole crickets, Gryllotalpa, are insect pest distributed in the world. In Korea, G. orientalis was reported to occur, but previous ecological studies suggested the presence of two ecological types. To test this hypothesis, we sequenced a portion of mitochondrial (mt) genome from 48 G. orientali individuals collected over five Korean localities: Busan, Suwon, Okchon, Wonju, and Gangneung. From the sequence analysis, only two haplotypes were obtained, but the sequence divergence between the two haplotypes was 11 %, suggesting the presence of two distinct genetic groups in Korea. Although the population of Busan, Okchon, Wonju, and Gangneung was identified as a single haplotype, but that of Suwon was occupied by both hapotypes. Considering sequence divergence of other insect species occurring in Korea, the divergence estimate found between the two haplotypes seems to be too large to be considered as identical species. This result may suggest that the two differentiated haplotypes found in this study may reflect the previously reported two ecological types found in Suwon, Korea. To further understand the genetic divergence of the two phylogenetic groups, analysis of more variable regions of G. orientalis genome is required.

• Journal of the Korean Institute of Gas
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• v.5 no.3 s.15
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• pp.63-72
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• 2001

An alternating current (AC) corrosion using coupon and electric resistance (ER) probe has been studied. Coupon coupled with ER probe were applied in terms of AC voltage from high value to low value through the survey of AC voltages on buried gas transmission pipeline over the country. Parameters such as AC current density of coupon, AC voltage, cathodic protection potential, soil resistivity and frequency were monitored continually. Corrosion induced by AC was observed even under cathodically protected condition that met cathodic protection criterion (below -850mv vs. CSE). Corrosion rate was affected mainly not by AC voltage but by both of frequency and AC current density. An experimental corrosion rate relationship could be obtained statistically, In which AC corrosion rate increased linearly with effective AC current density and its slope was 0.619 in case of coupon and 0.885 in case of ER probe.

• Journal of Ginseng Research
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• v.36 no.4
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• pp.396-402
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• 2012

Vaccination is the main strategy for preventing influenza infection. However, vaccine efficacy is influenced by several factors, including age and health status. The efficacy of the influenza vaccine is much lower (17% to 53%) in individuals over 65 yr of age compared with young adults (70% to 90%). Therefore, increasing vaccine efficacy remains a challenge for the influenza vaccine field. In this study, we investigated the impact of supplementing vaccination with the dietary intake of Korean red ginseng (RG) extract and RG saponin. Mice were immunized two times intranasally with inactivated influenza A (H1N1) virus. Mice received RG extract or RG saponin orally for 14 d prior to the primary immunization. After the primary immunization, mice continued to receive RG extract or RG saponin until the secondary immunization. Mice vaccinated in combination with dietary intake of RG extract and RG saponin showed elevated serum anti-influenza A virus IgG titers and improved survival rates in lethal influenza A virus infection: 56% and 63% of mice receiving RG extract or RG saponin survived, respectively, while 38% of mice that only received the vaccine survived. Moreover, mice receiving RG extract supplementation recovered their body weight more quickly than those not receiving RG extract supplementation. We propose that the dietary intake of RG extract and RG saponin enhances the vaccine-induced immune response and aids in providing protection against influenza virus infection.

• Journal of Radiation Protection and Research
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• v.13 no.2
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• pp.57-66
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• 1988

A series of experiments is performed to measure radon concentration in the near-surface soil gas at the four locations (Cheju-Si, Seoguipo-Si, Taejeong-eup, Seongsan-eup) in Cheju Island, using CR-39 detectors placed inside radon cups. Two types of radon cups are installed in shallow holes of about 15 cm in diameter and 50cm in depth. The optimum etching conditions, i.e., the concentration of NaOH solution, etchant temperature and etching time, are found to be 625N, $70^{\circ}C$ and 5.5 hours for CR-39 detectors. A typical conversion factor of radon cup is calculated as $$1track/mm^3{\cdot}30day=0.059Bq/{\ell}$$. Average radon concentrations over 30 days measured in Cheju Island from May 1, 1987 to April 23, 1988 are $3.1{\pm}0.3Bq/{\ell}$ for open radon cups and $1.7{\pm}0.2Bq/{\ell}$ for closed radon cups.

• The Journal of Internal Korean Medicine
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• v.43 no.6
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• pp.1162-1185
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• 2022

Purpose: We examined the effects of Dansam (Salvia miltiorrhiza Bunge, SM) and Dansam-eum (DSE) on gastroesophageal reflux disease (GERD) and reflux esophagitis by comparing the inhibitory effects of SM and DSE with the representative treatment of PPI Omeprazole to determine if the effects of the prescription DSE based on Korean medicine are better than those of a single-use of SM. Methods: We performed experiments using both animal models and cancer cells. Results: Comparison of SM and DSE with PPI in the animal model tests revealed that the effects were superior for SM and DSE than for PPI in all categories (8-OHdG, p-IκB, PAR2, COX-1, cathelicidin, p-JNK, Caspase 3, ATP6V1B1, GRPR, serotonin, and NPY). In three categories (COX-1, serotonin, and NPY), SM and DSE showed superior results over the Controls. In the animal model tests, DSE was superior to SM in all categories except for serotonin. The anti-cancer effects observed in cancer cell tests revealed that SM and DSE had meaningful results in terms of cytotoxicity and cell movement rate, as well as in cancer cell apoptosis. Conclusions: We confirmed that SM and DSE can have effects on reflux esophagitis through the regulation of oxidative stress, inflammation, mucosal protection, apoptosis, proton pumping, and the enteroendocrine system in the stomach and esophagus. We also confirmed that SM and DSE have superior effects to those of PPI on all aspects, especially gastric mucosa protection and enteroendocrine system control. We also confirmed that SM and DSE have anti-cancer effects. Above all, we confirmed that DSE has superior effects on almost all aspects compared to using SM alone.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.1
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• pp.46-55
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• 2017

In this study, extracts of gamma-irradiated Aralia continentalis for health and beauty food resources were examined on antioxidant activities and increasing extraction yield. In photostimulated luminescence analysis, non-irradiated (0 kGy) sample showed an intermediate result of 891.00 photon counts (PCs), whereas irradiated (5 and 10 kGy) samples showed positive results of 79,956.67 and 282,498.67 PCs, respectively. The thermoluminescence ratio of non-irradiated samples was 0.018, whereas the values of irradiated samples (5 and 10 kGy) were 0.395 and 0.464, respectively. Electron spin resonance (ESR) analysis as a physical technique for irradiation identification of Aralia continentalis showed a pair of peaks on a space of 6.0 mT in the symmetric ESR spectrums. For phenolics of gamma-irradiated Aralia continentalis, water extracts had the highest amounts of 7.61 mg/g at non-irradiated condition (0 kGy) while 50% ethanol extracts had the highest amounts of 6.86 mg/g at 10 kGy irradiation. 2,2-Diphenyl-1-picrylhydrazyl scavenging activity of water and 50% ethanol extracts from non-irradiated and irradiated Aralia continentalis were very high (94.99~100.00%). 2,2'-Azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) radical cation inhibitory activity was over 95.00% at $200{\mu}g/mL$ phenolics. Antioxidant protection factor (PF) showed a very high level of activity (1.38~2.51 PF). Thiobarbituric acid reactive substance inhibitory activity was high (70% and 95%, respectively). Thus, treatment of gamma irradiation can be used as a method of storage for long-term preservation of Oriental medicine.