• Korean Journal of Ecology and Environment
• /
• v.51 no.1
• /
• pp.40-59
• /
• 2018

This review summarizes the history of freshwater zooplankton research in Korean Society of Limnology and necessary future topics that are remain poorly investigated in South Korea based on main research topics of published articles focusing on lakes, reservoirs, rivers and wetland ecosystems. In Korea, a total 450 freshwater zooplankton species have been reported (85 species of cladocera, ca. 230 species of rotifera since 1939, and 138 species of copepoda), and they cover 10% of total zooplankton species list. In the present paper, we provide recent species list of zooplankton found in Korea and their taxonomic keys. Over periods of 45 years, there are 25 published papers for zooplankton biota in lentic ecosystems in Korean Journal of Ecology and Environment (KJEE). The ecology of zooplankton communities in rivers has focused on the mechanisms involved in regulating their abundance, diversity and spatio-temporal patterns of genus Bosmina and rotifers (genus Brachionus and Keratella) that are most frequently found from Korea. On the other hand, the studies on zooplankton in wetland has focused on Alona, Chydorus and Ceriodaphnia with special emphasis on their relationships with aquatic macrophytes. Even though studies on the freshwater ecosystem in Korea have a long history, a few of studies on zooplankton biota were conducted at rice paddy, Dumbeong and wetlands. During the last two decades, experimental advances in freshwater zooplankton ecology and understanding of structure and function of this biota were made from a series of articles mainly in journal of KJEE. For future studies, quantitative, experimental and interdisciplinary approaches would be key words to understand zooplankton ecology and their roles in aquatic ecosystems under changing environments, and we have suggested necessary zooplankton research fields and future directions.

• Korean Journal of Food Science and Technology
• /
• v.36 no.6
• /
• pp.1001-1007
• /
• 2004

Chloroform layer from methanol extract of Corni fructus (Cornaceae) showed strong antiproliferation effect on human cancer cell lines by SRB assay. Anticarcinogenic-active compound was isolated and purified by silica gel column and thin layer chromatograpies, and identified as ursolic acid ($3{\beta}$-hydroxyrus-12-ene-28-oic acid, MW:456) by mass and IR spectrophotometries, and $^1H-and\;^{13}C-NMRs$. The compound inhibited proliferation of A549 (human lung cancer cell line) and MCF-7 (human breast cancer cell line) cells in dose-dependant manner when treated for 48 hr. Inhibition rates of both cells were over 40% and 90% compared with control cells at the $30\;{\mu}g/mL\;and\;100\;{\mu}g/mL$, respectively. Morphology of cells treated with the compound for 15 hr at $10\;{\mu}g/mL$ was distorted with shrinked cell mass, and cell number was lower than that of control cells. Cell cycle analysis showed sub-G1 phase arrest in both cell lines following 15 hr exposure to the compound; % of cell phase increased to 11.7 and 11.2% compared to the control of 4.0% and 2.1% in A549 and MCP-7 cells, respectively.

• Molecular & Cellular Toxicology
• /
• v.4 no.4
• /
• pp.278-284
• /
• 2008

The X-linked inhibitor of apoptosis (XIAP) is a member of a novel family of inhibitors of apoptosis and has several BIR domains (BIR1, BIR2, and BIR3) and a carboxy-terminal RING zinc-finger. Since suppressionof apoptosis is fundamentally important for carcinogenesis and tumor growth, we investigated the expression and function of XIAP in DEN-induced carcinogenesis using rat model. Wistar rats were injected intraperitoneally with DEN at a dose of 50 mg/kg in twice a week for 12 weeks (Group II) and 16 weeks (Group III) followed by the recovery periods, respectively. The evaluation of DEN-induced carcinogenesis carried out the blood, RT-PCR, histopathological and western blot analysis. The level of blood chemistry including GOT/GPT, albumin, and total bilirubin were significantly exchanged comparing to control and Group I/Group II. The expression of albumin and collagen mRNA were significantly exchanged (P<0.05) in both groups. In addition, AFP mRNA expression decreased more after recovery periods than Group II. XIAP was expressed constitutively in normal rat liver as well as DEN-induced Groups I and Group II. In addition, XIAP expression increased more in Group I with 4 weeks recovery periods than Group I. However, XIAP expression shown to increase in Group lI, otherwise, it was decreased in Group II with 10 weeks repair periods. Taken together, these results suggest the alteration of XIAP expression could be involved in hepatocellular carcinogenesis.

• Journal of Applied Biological Chemistry
• /
• v.55 no.1
• /
• pp.55-59
• /
• 2012

We designed a new rapid detection method for volatilized formaldehyde from wood. The process was installed with volatilizing and collecting parts in an incubator. For rapid sampling of formaldehyde from wood, we pulverized the wood to sawdust, and used 0.15-2.0 mm particles for the tests. The highest sampling rate (94.8%) was obtained at 40 mL/min flow rate and $100^{\circ}C$. Under the optimized condition, we could collect the volatilized formaldehyde with good recovery rate. The developed method was applied to the monitoring of the formaldehyde from wood, and the measured concentrations were 0.7-4.6 ${\mu}g/g$ from natural wood, 5.9-12.3 ${\mu}g/g$ from preserved wood, and 5.9-211.5 ${\mu}g/g$ from chemical adhesive processed wood. From the results, we identified natural wood sawdust and chemically processed wood (medium density fiberboard, high density fiberboard, particle board) by the formaldehyde contents except preserved wood.

• Genomics & Informatics
• /
• v.10 no.3
• /
• pp.175-183
• /
• 2012

Colorectal cancer (CRC) is among the leading causes of cancer deaths and can be caused by environmental factors as well as genetic factors. Therefore, we developed a prediction model of CRC using genetic risk scores (GRS) and evaluated the effects of conventional risk factors, including family history of CRC, in combination with GRS on the risk of CRC in Koreans. This study included 187 cases (men, 133; women, 54) and 976 controls (men, 554; women, 422). GRS were calculated with most significantly associated single-nucleotide polymorphism with CRC through a genomewide association study. The area under the curve (AUC) increased by 0.5% to 5.2% when either counted or weighted GRS was added to a prediction model consisting of age alone (AUC 0.687 for men, 0.598 for women) or age and family history of CRC (AUC 0.692 for men, 0.603 for women) for both men and women. Furthermore, the risk of CRC significantly increased for individuals with a family history of CRC in the highest quartile of GRS when compared to subjects without a family history of CRC in the lowest quartile of GRS (counted GRS odds ratio [OR], 47.9; 95% confidence interval [CI], 4.9 to 471.8 for men; OR, 22.3; 95% CI, 1.4 to 344.2 for women) (weighted GRS OR, 35.9; 95% CI, 5.9 to 218.2 for men; OR, 18.1, 95% CI, 3.7 to 88.1 for women). Our findings suggest that in Koreans, especially in Korean men, GRS improve the prediction of CRC when considered in conjunction with age and family history of CRC.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.10 no.1 s.20
• /
• pp.61-67
• /
• 2004

This study described relationships between fluctuation of fishing conditions for common squid and oceanic conditions in the East Sea from 1990 to 1999. Annual catches of common squid have been higher since the late 1980s compared to the period of the late 1970s to the mid-1980s. These catches fluctuations might be related to the effect of regime shifts. Monthly catches of common squid appear the timing of a large catch from September to December and a poor catch from March to May. The monthly catches are also the highest in October and are the lowest in April. Annual stable fishing grounds for coefficient of variation below 1.0 are formed in waters around Guryongpo and Ullung Island Based on optimum water temperature for catch, $16^{\circ}C$, optimum water depth for catch shallow going north. It indicates that the optimum water depth of fishing work different of each area Fishing ground formation and horizontal water temperature appear the minimum $10{\sim}14^{\circ}C$ in April, the maximum $10{\sim}20^{\circ}C$ in October. If seem, that seasonal fluctuation of fishing ground is related to the extension of the Tsushima warm current in the East Sea.

• Journal of Sasang Constitutional Medicine
• /
• v.22 no.1
• /
• pp.34-40
• /
• 2010

1. Objectives: Leptin is ob-gene originated hormone that is concerned with energy metabolism, obesity and asthma which features are supposed to related with Sasangin's 4 viscera physiological theory of Sasang constitutional medicine(SCM). This study aims to investigate whether serum leptin concentration is associated with Sasangin. 2. Methods: Two Way ANOVA analysis was used on the constitution and serum leptin concentration corresponding with BMI among 1054 cases drawn from the Constitutional Information Bank, which was a database with clinically confirmed constitution cases collected from 21 oriental medical institutes in Korea starting from November 2007 to May 2009. The measurement of serum leptin concentration is implemented through radioimmunoassay by request to SCL. 3. Results: Male subjects showed notable difference(p=0.033) in the comparison between constitution and serum leptin concentration corresponding to BMI levels. Tae-eumins showed the highest serum leptin concentration levels in the normal and overweight groups, followed by Soyangin and Soeumin. As the groups changed from overweight to obese, there was an interaction phenomenon in the order of serum leptin concentration levels(p=0.040). As a result, Soeumins showed the highest serum leptin concentration levels and Tae-eumins and Soyangins followed in place. Female subjects did not show statistically notable differences in comparison between constitution and serum leptin concentration corresponding to BMI levels(p=0.239). Serum leptin concentration levels among overweight and obese groups, resulted in the order of Soeumins, Tae-eumins, and Soyangins. But in the as groups changed from overweight to normal the order resulted in Tae-eumin, Soyangin, and Soeumin(p=0.660). 4. Conclusion: Due to a number of limitations in this study, the examination of the relation between constitution and leptin, a main hormone responsible for the digestion, appetite, and energy metabolism, resulted to be uncertain. But statistically notable differences were confirmed in male Tae-eumins with the consideration of BMI. Further examination of the relation between constitution and leptin is necessary through prospective studies with the restriction of confusion variables in the future.

• The Korean Journal of Food And Nutrition
• /
• v.29 no.3
• /
• pp.431-437
• /
• 2016

Macrophages play a pivotal role in the innate and adaptive immune systems. This study investigated the immuno-modulatory activities of polysaccharides separated from Chrysanthemum zawadskii var. latilobum (CZPS) in macrophages. Polysaccharides from Chrysanthemum zawadskii var. latilobum were extracted by the ethanol precipitation method. RAW 264.7 mouse macrophage cell line was treated with CZPS (4 to $128{\mu}g/mL$), and there was no cytotoxicity at a dose below $32{\mu}g/mL$. The levels of nitric oxide (NO) and pro-inflammatory cytokines (tumor necrosis factor (TNF)-${\alpha}$ and interleukin (IL)-6, IL-$1{\beta}$) production in the CZPS treated group ($32{\mu}g/mL$) were $6.5{\pm}0.12{\mu}m$ (NO), $1252.8{\pm}79.85$ (TNF-${\alpha}$), $305.4{\pm}29.41$ (IL-6), and $683.3{\pm}59.71$ (IL-$1{\beta}$), respectively, and they were significantly increased when compared to the control group; $2.2{\pm}0.03{\mu}m$ (NO), $452.3{\pm}38.34$ (TNF-${\alpha}$), $31.7{\pm}5.75$ (IL-6), and $184.1{\pm}11.52$ (IL-$1{\beta}$). Additionally, protein expression of inducible nitric oxide synthase (iNOS) and phosphorylation of MAPKs and NF-${\kappa}B$ expression were significantly increased upon CZPS treatment. Therefore, these results indicated that polysaccharides separated from Chrysanthemum zawadskii var. latilobum (CZPS) may have a potential immunomodulatory activity in macrophages through MAPKs and NF-${\kappa}B$ signaling, and this information is useful for the development of immune enhancing adjuvant materials using a natural ingredient.

• Journal of Korean Society of Environmental Engineers
• /
• v.35 no.3
• /
• pp.213-219
• /
• 2013

We have investigated the correlation between odorous compounds and actinomycetes in drinking water source of Nakdong River in 2011. Geosmin was mainly detected in the spring and summer seasons (Mar, Aug, and Sep) and 2-MIB was mainly detected in the winter and spring seasons (Feb, Mar and May). The odorous compounds concentrations were highest on March which also overlapped with the peak of actinomycetes, geosmin and 2-MIB were detected highly in the diluted culture solution of isolated actinomycetes strains from Nakdong River. For these reasons we could confirm that odorous compounds on March and August are closely related with actinomycetes. Meanwhile, geosmin increase on September supposed to relate with Microcystis.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.37 no.8
• /
• pp.1-10
• /
• 2000

Performance analyses of hybrid DS-SFH spread-spectrum systems using coherent MSK and QPSK modulation techniques are considered over Rayleigh fading channel in the presence of multi-tone jamming. The BER equations for MSK and QPSK systems with non-diversity reception in the receiver are derived as the concept of average signal-to-noise power ratio E$\_$b//N$\_$0/ and jamming-to-signal power ratio JSR, and the performances is evaluated for various system parameters. The evaluation of performance is done between fading and nonfading system, and between MSK and QPSK system. Results show that the performances of two systems are similar in low JSR. However, MSK system outperforms QPSK system as JSR increases. Overall performances of two systems are a little improved as the DS spreading gain increases for the total spread-spectrum bandwidth fixed. The performance difference between fading system and nonfading system is similar in low E$\_$b//N$\_$0/, however, it becomes very largewith increase of E$\_$b//N$\_$0/..