• Molecules and Cells
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• v.25 no.2
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• pp.258-264
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• 2008

Deschampsia antarctica is the only monocot that thrives in the tough conditions of the Antarctic region. It is an invaluable resource for the identification of genes associated with tolerance to various environmental pressures. In order to identify genes that are differentially regulated between greenhouse-grown and Antarctic field-grown plants, we initiated a detailed gene expression analysis. Antarctic plants were collected and greenhouse plants served as controls. Two different cDNA libraries were constructed with these plants. A total of 2,112 cDNA clones was sequenced and grouped into 1,199 unigene clusters consisting of 243 consensus and 956 singleton sequences. Using similarity searches against several public databases, we constructed a functional classification of the ESTs into categories such as genes related to responses to stimuli, as well as photosynthesis and metabolism. Real-time PCR analysis of various stress responsive genes revealed different patterns of regulation in the different environments, suggesting that these genes are involved in responses to specific environmental factors.

• Korean Journal of Environmental Biology
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• v.31 no.3
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• pp.189-191
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• 2013

Mycotoxins such as aflatoxin B1 (AFB1), ochratoxin A (OTA) and zearalenone (ZEA) are widespread contaminants of food and feedstuffs. It is very likely, that humans and animals are always exposed to mixtures of mycotoxins rather than to individual compounds. Therefore, risk assessments should consider mixture toxicity data. In the present study the combination of AFB1, OTA and ZEA was tested for genotoxicity in rat bone marrow and blood leukocytes after 15, 30 and 60 days treatment. The level of DNA damage was determined by the comet assay. The tail intensity and Olive tail moment in leukocytes and bone marrow cells were significantly higher than in controls. At the same time, the level of DNA damage in bone marrow cells was higher than in leukocytes. The data suggests that prolonged exposure to mycotoxins combination through food consumption can induce DNA damage contributing to the harmful effects in vivo.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.19 no.3
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• pp.195-201
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• 2009

To identify relationship between the airborne concentrations of formaldehyde and the causal factors in the endoscope unit of hospitals, a total of 48 workers selected from 4 hospitals (3 university hospitals and 1 national hospital) were investigated. Airborne formaldehyde samples were collected using passive samplers and subsequently analyzed by HPLC according to the OSHA method 1007. The geometric mean(GM) of airborne formaldehyde concentrations was 0.056 ppm (range: 0.003~0.923 ppm). The rates of exceeding exposure limits of OSHA PEL-TWA and NIOSH REL-TWA were 4.2 % and 83.3%, respectively. The STEL GM concentration was 1.428 ppm(range: 0.103~14.773 ppm). Ventilation condition (p=0.001) and temperature (p=0.017) were statistically significant causal factors for the airborne exposure concentration of formaldehyde in the endoscope unit of hospitals. In conclusion, the workers in the endoscope unit of hospitals were highly exposed to formaldehyde, and adequate controls such as appropriate management of ventilation and temperature are recommended to reduce over exposure to formaldehyde.

• Toxicological Research
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• v.18 no.4
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• pp.341-347
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• 2002

Hypertension is a multifactorial disorder in which the genetic and environmental factors are involved. In a view of the effects for hypertension as a risk factor for hypertension, we investigated the genotype and allele frequencies in the four RFLPs of the apo AI-CIII-AIV gene cluster (G to A mutation at position -75 in the apo AI promoter SstI RFLP in the ape CIII gene and HincII and HinfI RFLPs in the apo AIV gene) in the Korean patients with hypertension and normal controls. The AA genotype frequency of the G to A promoter polymorphism in hypertensives was significantly higher than that of normotensives (P < 0.05). None of the other polymorphisms showed a difference in genotype frequency between two groups. Therefore, our result suggest that the G to A promoter polymorphism of the ape AI gene may be useful as genetic marker in the ethiology of hypertension.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 2003.10a
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• pp.158-158
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• 2003

Bioassays using gametes of sea urchins are widely used in ecotoxicological assessments of marine environments. Since most of sea urchin species in Korean coastal water spawn from spring to autumn, bioassay with them during the winter is impossible. In the course of developing standard methods for bioassays with Korean species, we found a winter-spawning starfish, Asterias amurensis, Since reproductive mode of asteroids is similar to echinoids, the bioassay protocol for sea urchins could be applied similarly to the starfish. Here, we tested and determined several conditions for the acceptability of bioassay with A. amurensis. The least required time for formation of fertilization membrane of fertilized eggs to be easily distinguished from unfertilized ones was 60 min. The threshold of sperm to egg ratio that could make acceptable fertilization rates in controls was 3000. The allowed time for manipulation of sperm after dilution in seawater was at most 3 hr. The optimal exposure time of sperms when the response against toxicant solution was relatively stable was in the range of 20-60 min. The tolerance range of sperms to the salinity of test solution was 26-38 psu. The sensitivity of A. amurensis sperm was intermediate among marine organisms commonly used in aquatic toxicity tests. The sperm bioassay with A. amurensis can be satisfactorily applied to toxicity assessments of marine environments.

• Journal of Applied Biological Chemistry
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• v.55 no.1
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• pp.27-34
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• 2012

Soy protein isolate (SPI)-based edible coating, with and without carboxymethyl cellulose (CMC), were used to reduce oxidative degradation of cut pork stored at $4^{\circ}C$ for 5 days. The SPI coating reduced (p<0.05) thiobarbituric acid-reactive substances (TBARS) and peroxide value (PV), compared with controls. The inhibition of TBARS and PV for SPI-coated porks with and without CMC, compared with the control was 19.1 and 23.9, and 25.7 and 37.7%, respectively. The SPI coating prevented loss of $L^*$ and $a^*$ values of porks compared to the control. The ability of the SPI coating to provide a moisture barrier for the porks was reduced (p<0.05). The SPI-coated porks with and without CMC reduced moisture loss by 37.3 and 44.6%, respectively, over the control. However, SPI coating of porks did not inhibit the growth of either total plate counts or L. monocytogenes. The result revealed that SPI can effectively be used as a natural antioxidative coating to extend quality and shelf life of pork.

• The Journal of Engineering Geology
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• v.16 no.3 s.49
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• pp.301-306
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• 2006

Damages of cultural properties is caused by subsidence of foundation relating stone structures. To prevent of these structures, ground monitoring should be achieved certainly. Representative ground subsidence cause is saturated and unsaturated condition that is produced repeatedly by groundwater level fluctuations. It controls role that decrease porosity or effective porosity of soil media. Estimation of physical properties can predict from reaction of dielectric constant. Variations of dielectric constants are measured from physical characteristics change of pore, soil particle, air and water which are consisted to ground. Therefore, ground subsidence monitoring is thought that quantitative measurement is available using dielectric response of media.

• Environmental Analysis Health and Toxicology
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• v.21 no.4 s.55
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• pp.349-355
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• 2006

Dextromethorphan hydrobromide (DXM) has been widely used as a nonopioid antitussive drug with low toxicity and low potential for drug dependency. DXM is a psychotropic drug since 2003 in our country. This study was performed to investigate the immunotoxicity induced by abuse of DXM. Mice were orally exposed to DXM dissolved in saline as concentration of 30, 60, and 120 mg/kg b.w. before (day-2) or after (day+2) immunization (OVA-antigen, day 0). Thereafter, we measured the increased rate of body weight, relative weight of organ (thymus, spleen, liver, kidney) and OVA-specific IgM level in sera. In addition, mouse splenocytes were exposed to various concentration of DXM $(0.001{\sim}100{\mu}M)$ and cultured with B cell mitogen (LPS) and splenocytes proliferations (SP) were measured by MTT-assay. Thymus-weight were slightly changed on day 9 after administration of DXM, but body-, spleen-, liver-, and kidney-weight were not different between control group and DXM-treated group. SP to LPS were significantly decreased at high concentration $(100{\mu}M)$ when compared with controls. When DXM was administered before or after immunization with OVA-antigen, OVA-specific IgM levels were significantly lowered in a dose-dependent manner. These results indicate that DXM nay depress the primary humoral immune response to the initial antigenic challenge.

• Journal of Environmental Science International
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• v.7 no.2
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• pp.133-140
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• 1998

To investigate the effects of sulfite on the chloroplast development, etiolated barley seedlings were treated with 100 mM sulfite solution every 3 hour by spraying during 96 hours greening Period. The effects were determined by chlorophyll a, b and carotenoids contents, photosynthetic electron transport activity, chlorophyll fluorescence yield and fluorescence quenching parameters. The contents of chlorophyll a and carotenoids were decreased than that of control by treatment of salfite over 48 hours greening. PS II Is more sensitive to sulfite than PS I Is. And by the addition of DPC to the chloroplasts of the barley seedling treated with sulfite, the photoreduction of DCPIP was not recovered. In greening with suite treated barley leaves, Fo, Fv and Nlh ratio were decreased with little difference from that of control. But qP, qNP and qR were lowed in comparison with those of controls whereas qE was markedly higher than that of control. Especially, It is Interesting that qR was decreased markedly compared to that of control. The results in the change of PS I activity, Nf and qP suggest that the strate of Inhibition by suite Is carbon dioxide reduction cycle.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.05a
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• pp.19-22
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• 2011

For underground structures that are exposed to environmental conditions, the declination of the durability of concrete occurs easily because of leakages from high hydraulic pressure and the frequent contact of water due to environmental factors. Therefore this study is to confirm that the leakage reduction of natural inorgnic powder compound applying subsurface structural weak part and make the performance improvement of concrete as an objective. The test was done by making the rebar, flat tie, nail and film infiltration and each of its water tank and cylindrical test body then after pouring water to each of the test body, the test observe the change of the water tank surface absorbed condition and leakage of each specimen with respect to time. As a conclusion, the test was observed that this water proofing admixture has better watertightness from the beginning of the setting time(when it hardens), the ettringite and the thaumasite generates a large quantity of hydration products that controls the formation in a large opening and the CSH produced by pozzolan reaction makes a dent at this opening.