• Journal of fish pathology
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• v.17 no.3
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• pp.199-205
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• 2004

Effects of nitrite, ammonia and hydrogen sulfide on survival of the early developmental stages of Fenneropenaeus chinensis were determined under continuous flow-through system. The 96hr-$LC_{50}$ values of mysis stage were 18.4 mg/L, 0.69 mg/L and 13.5 $\mu{g}/L$ for nitrite, ammonia and hydrogen sulfide, respectively; 28.3 mg/L, 1.23 mg/L and 20.7 $\mu{g}/L$ for post larva stage and 39.8 mg/L, 1.73 mg/L and 28.5 $\mu{g}/L$ for juvenile stage, respectively. The Fenneropenaeus chinensis sensitivity for the three pollutants was in the order of hydrogen sulfide>ammonia>nitrite. The mysis/post larva, mysis/juvenile and post larva/juvenile ratios of nitrite, ammonia and hydrogen sulfide toxicity were >1.5, >2.0 and <1.5 times, respectively, and mysis were found to be more sensitive to pollutants than juvenile in all cases.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.8
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• pp.795-801
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• 2010

The acute toxicity of arsenic compounds was assessed and compared using following four bioassays; bioluminescence activity of the recombinant strain RB1436, germination of four different seeds, ${\alpha}$-glucosidase activity produced by Bacillus lichemiformis, acute genetic revertant mutation using mutant strain Salmonella typhimurium. Different sensitivities were observed among tested bioassays, but generally the toxicity by arsenite was greater than that of arsenate. Among tested four seeds, sensitivities of Lactucus and Raphanus were greater than others, and these two seed types were appeared as proper type for bioassay. High revertant mutation ratio (5.1) was observed with 1 mg/L arsenite, indicating high mutagenicity. The sensitivity of ${\alpha}$-glucosidase activity on arsenic compounds was much lower than other methods. The evaluation of interactive toxic effects using various bioassays may comprise a useful tool for the bioassessment of environmental pollutants.

• Journal of the Korean Society of Urban Environment
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• v.18 no.4
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• pp.429-437
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• 2018

In this study, the mixed toxicity of heavy metals (Cu, Pb, Hg) and surfactants (SLS, ALS) was evaluated by using Vibrio fischeri and Daphnia magna. The sensitivity of ecotoxicity to heavy metals was sensitive to daphnia but the case of surfactants were more sensitive to Vibrio fischeri. Experimental results of Vibrio fischeri show that the toxicity value P(O) was lower than the predicted value P(E), and the antagonistic effect was observed when the heavy metal and the surfactant were mixed. It seems that SLS and ALS, which are anionic surfactants, have anionic form on the hydrophilic head, so that they have an antagonistic effect that they are bonded with heavy metal ion which is a cation type and the actual toxicity is lowered. In Daphnia magna, the results showed that antagonistic, additive and synergistic effects were in order as concentrations increased. As the concentration increases, Daphnia magna, which is highly sensitive to heavy metals, seems to have a synergistic effect with a rapid increase in mortality.

• Journal of Marine Life Science
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• v.6 no.2
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• pp.80-87
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• 2021

In this study, the toxic effects of PFOA and PFOS potassium salt on Mesocentrotus nudus using 10 min-fertilization rate and 48 h-normal embryogenesis were confirmed through the calculation of toxicity values such as Non-observed effective concentration, Low-observed effective concentration, and 50% of effective concentration. The case of 10 min-fertilization rate and 48 h-normal embryogenesis showed the concentration-dependent reduction pattern when exposed to PFOA and PFOS potassium salt, in tested concentration, respectively. The EC50 values of 10 min-fertilization rates for PFOA and PFOS potassium salt were 1346.43 mg/l and 536.18 mg/l, respectively, and the EC50 values of 48 h-normal embryogenesis were 42.67 mg/l and 17.81 mg/l, respectively. Both toxicity test methods showed high toxicity sensitivity to PFOS potassium salt. Recent studies have shown that the concentration of PFOA and PFOS in the marine environment has continuously decreased, and it is not enough to show acute toxicity to sea urchin. However, PFOA and PFOS have a very long half-life and can accumulate throughout the life of marine life, so it is still observed at a high concentration in shellfish. Therefore, a study on chronic toxicity through the whole-life cycle of marine organisms in coastal environments should be needed.

• Biomolecules & Therapeutics
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• v.7 no.4
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• pp.342-346
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• 1999

This study was performed to investigate the effect of cyclosporine (CsA) on glucose tolerance and peripheral insulin sensitivity in normal Sprague-Dawley rats. After daily treament of CsA (10 mg/kg, i.p.) for two weeks, glucose tolerance tests were carried out by the treatment of glucose (Glu, 2 g/kg, i.p.) alone or in conjunction with exogenous insulin (Ins; human regular insulin, 5 U/kg, s.c.) and measured the decrement of area under the time-plasma glucose concentration curve ($AUC_{o\longrightarrow120}$; g.min/ml) by the trapezoidal rule. The rats were divided into three groups (Glu- (Control), Ins+Glu- and CsA+Ins+Glu-, n=7 in each group). The $AUC_{o\longrightarrow120}$ of the CsA+Ins+Glu-group was significantly (p<0.01) lower than that of Glu-group (61.0% of control) and significantly (p<0.05) higher than that of Ins+Glu-group (197.4% of Ins+Glu-). The CsA+Ins+Glu- grou showed higher levels of maximal blood glucose concentration and higher $AUC_{o\longrightarrow120}$ than those of Ins+Glu-group in normal rats. Besides direct pancreatic toxicity of CsA previously reported (Hahn et al., 1972), these results suggest that CsA also make the possibility to induce peripheral insulin insensitivity and glucose intolerance in normal rats.

• Korean Journal of Ecology and Environment
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• v.45 no.4
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• pp.420-443
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• 2012

An Individual-Based Model (IBM) was developed by employing natural and toxic survival rates of individuals to elucidate the community responses of benthic macroin-vertebrates to anthropogenic disturbance in the streams. Experimental models (dose-response and relative sensitivity) and mathematical models (power law and negative exponential distribution) were applied to determinate the individual survival rates due to acute toxicity in stressful conditions. A power law was additionally used to present the natural survival rate. Life events, covering movement, exposure to contaminants, death and reproduction, were simulated in the IBM at the individual level in small (1 m) and short (1 week) scales to produce species abundance distributions (SADs) at the community level in large (5 km) and long (1~2 years) scales. Consequently, the SADs, such as geometric series, log-series, and log-normal distribution, were accordingly observed at severely (Biological Monitoring Working Party (BMWP<10), intermediately (BMWP<40) and weakly (BMWP${\geq}50$) polluted sites. The results from a power law and negative exponential distribution were suitably fitted to the field data across the different levels of pollution, according to the Kolmogorov-Smirnov test. The IBMs incorporating natural and toxic survival rates in individuals were useful for presenting community responses to disturbances and could be utilized as an integrative tool to elucidate community establishment processes in benthic macroin-vertebrates in the streams.

• Analytical Science and Technology
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• v.25 no.6
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• pp.388-394
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• 2012

Cyanobacterial toxins, microcystins which exist in Korean lakes show strong toxicity to fish, cattles and human. In this study, we tried to analyze cyanobacterial toxin, microcystin in the Microcystis cultivation solution using test strip, although the most common analytical methods for the detection of microcystin are HPLC and ELISA. This new anlytical method used the advantages of high specifisity and rapidness of test strip, high sensitivity of fluorescence reader. Therefore, we could analyze the trace amount of microcystin existed in various water samples without using the microcystin standards.

• Biomolecules & Therapeutics
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• v.6 no.1
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• pp.20-24
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• 1998

In the present study, we tested whether lead intoxication induces change of the thiamine content and the seizure threshold in rats and the changes of seizure threshold are related to the changes of thiamine status. It was also tested whether administration of excessive thiamine could reverse the toxic manifestation of lead in rats. Four groups of Wistar rats were prepared: 1) control group, 2) lead treated group, 3) lead plusthiamine treated group, and 4) thiamine deficient group. Each group of animals was divided into three subgroups based on age: 3, 7 and 16 weeks. In each group, thresholds of electroshock seizure and thiamine contents in brain regions including telencephalon, brain stem, cerebellum were measured. Thiamine contents in brain regions of the lead treated group were significantly lower than those of the control group and thiamine treatment reversed the decrease back to the control level. Thresholds of the electroshock seizure of the lead treated group in 3, 7 week old rats and those of thiamine deficient group in 3 week old rats were significantly lower than those of the control group. These observations were reversed by the supplementation with thiamine. These results from the present study suggest that increased seizure sensitivity induced by lead intoxication in rats may be mediated at least in part through the changes of thiamine status.

• Journal of Korean Society on Water Environment
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• v.26 no.4
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• pp.574-579
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• 2010

In this study the enzyme inhibition method using dehydrogenase which has been popularly used to estimate ecotoxicity was optimized. When three bacterial strains, Escherichia coli HB101, Enterobacter asburiae KCAD-4, and Aeromonas media KCAD-13, were compared, KCAD-4 was considered as the adequate strain to estimate toxicity because of its sensitivity and reproducibility. The optimal bacterial density was estimated as $5.4{\times}10^9CFU/mL$, at which the maximum sensitivity was observed. The phosphate buffer was suitable for the reaction solution. When the reaction times required for inhibition of enzyme activity by contact of toxicants and for reaction of damaged bacteria and substrate were tested, the optimal value was estimated as 20 min and 2 hrs, respectively. It is expected that the optimized conditions can be used to develop the standardized kits to estimate ecotoxicity of heavy metals in effluent from the industrial wastewater treatment facilities.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.1
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• pp.293-297
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• 2013

Background: : Chemotherapy-induced thrombocytopenia (CIT) is an important cause of morbitity in patients with cancer. Aim: To investigate the effect of the baseline plasma D-dimer level, an important marker for thrombotic activity, on chemotherapy-induced thrombocytopenia in patients with stage III colon cancer. Materials and Methods: A total of 43 (28 men) eligible patients were divided into two groups according to whether they exhibited chemotherapy-induced thrombocytopenia: Group 1 (n=21) and Group 2 (n=22). Comparison was made using demographic, histopathologic, and laboratory variables. Additionally, baseline plasma D-dimer levels underwent receiver operation characteristics curve analysis, and areas under the curve were calculated. Sensitivity, specificity, and positive and negative likelihood rates were then determined. Results: The incidence of chemotherapy-induced thrombocytopenia had a significant correlation with baseline platelet count (r=0.568, P=0.031) and baseline plasma D-dimer levels (r=0.617, P=0.036). When the cut-off point for the latter was set as 498 ng/mL, the area under the curve was 0.89 (95%CI: 0.74-0.93), the sensitivity was 91.4%, the specificity was 89.7%, the positive likelihood rate was 3.64 and the negative likelihood rate was 0.24 for chemotherapy-induced thrombocytopenia diagnosis. Conclusions: The baseline level of plasma D-dimer could help to differentiate high-risk patients for chemotherapy-induced thrombocytopenia.