• 한국지하수토양환경학회지:지하수토양환경
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• 제18권7호
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• pp.12-17
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• 2013

Heavy metal contamination of soil and water from industrial sources remains a worldwide environmental concern. Concentrations of toxic metals were measured in soil from banks of the Han and Anyang rivers. Pre-monsoon samples contained the highest heavy metal concentrations (Cu > As > Pb > Cd > $Cr^{6+}$; up to 57.80, 38.23, 25.43, 2.21, 0.32 mg/kg, respectively), but concentrations decreased at all sites during the monsoon and post-monsoon seasons. Higher heavy metal concentrations in pre-monsoon samples may be attributed to dust pollution, especially from roads near the river. A gradual reduction in heavy metal concentrations during the rainy season may be due to washing out. The high concentration of metals could cause health problems, especially in residential areas.

• 환경위생공학
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• 제11권2호
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• pp.21-26
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• 1996

In our previous studies, we reported that lead intoxicated nerve cell by inhibition of the Na$^{+}$-K$^{+}$ ATPase activity and reduction of myo-inositol in nerve cell. As the second series of experiments, in order to understand toxic mechanism of lead for nerve cell, the characteristics of myo-inositol transport system and the effect of lead on its system have been studied in the sciatic nerves of control and lead-treated rats. A lead intoxicated animal model was induced by feeding diet containing lead to Sprague-Dawley rat for two weeks. Four weeks aged Sprague-Dawley rats were divided into three group : normal control group, 10ppm-lead treated group, 100ppm-lead treated group. All rats were sacrified at the end of two weeks. The rate o myo-inositol transport by sciatic nerve isolated from lead-treated rat was significantly decreased compared with that of control rat. This deficit results from that myo-inositol transport system which is carrier mediated and sodium-potassium dependent was inhibited by the lead treatment (both 10ppm and 100ppm) due to increase of the Km value without affecting Vmax value for myo-inositol carrier. These observations suggest that the toxic mechanism of lead on nerve myo-inositol transport system might be a change of affinity without change of maximum transport velocity for carrier.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2004년도 춘계학술발표회
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• pp.81-84
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• 2004

Control of Sediment is very important in prawn farm due to the eruption of toxic material such as W1ionized H2S, NH3 and NO2-. In this study, column test study, column with filter media such as activated carbon, zeolite, oyster shell and iron chloride to evaluate the reduction of toxicity from sediment ammonia-N(NH3) was effectively removed by Zeolite and oyster shell. It was indicated that ammonium ion(NH4+) was removed by ion exchange of zeolite. And the ammonia in the column of oyster shell was existed as the form of NH4+, which is not toxic for prawn because oyster shell was stably kept around pH 8. Therefore, some of ammonia(NH3) was reduced by oyster shell. Hydrogen sulfide and COD were effectively removed by adsorption of activated carbon and a partial removal of hydrogen sulfide was accomplished by Oyster shell. Phosphorous was removed by activated carbon, oyster shell and iron chloride. In prawn farm, the concentration of ammonia was increased with increase of pH by algae photosynthesis in the column of activated carbon, zeolite and iron chloride, but it was revealed that pH was stably kept in the column of oyster shell.

• Journal of Nutrition and Health
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• 제14권1호
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• pp.26-33
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• 1981

Crocin was extracted from Gardenia fructus in order to manufacture a natural food dye. In the extraction and purification process methanol and ethanol were used as the most Suitable solvent selected in preliminary test and 9.28%g/100g of Cretin product in 99.89% of purity was acquired. The lethal dose of Cretin administered in mouse by intra peridoneal was 5.36g/kg which is much lower toxic than any other. The toxic dose which caused diarrhoea in rat was 2.55g/kg and maximum no effect level was found to be 272mg/kg. From the $1%{\sim}2.5%$ content of Crocin in rat diet reduction of body weight appeared and GTP and GOT (Transaminase) value in creased significantly. Crocin showed a good properties of tolerating acid, alkali, sunlight, reductant, oxidant, and salt compared with tar dyes. The range from 100 ppm to 500ppm bring out bright $yellow{\sim}orange$ color, the most effective color, with a good solubility in water-slightly in oil. The acceptable daily intake of crocin was calculated as 2.72mg/kg based on maximum no effect dose (2% additive dose).

• Fisheries and Aquatic Sciences
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• 제14권4호
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• pp.355-361
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• 2011

Effects of aluminum (Al) on plasma vitellogenin (VTG), alkaline-labile phosphorus (ALPP), calcium (Ca), glutamate pyruvate transaminase (GPT), the hepatosomatic index (HSI), and hepatic Al concentration were examined in estradiol-$17{\beta}$ ($E_2$)-administered immature rockfish Sebastes schlegeli. Fish were injected intraperitoneally with $E_2$ (5 mg/kg body weight [BW]) and/or Al (0, 0.1, 1, 5, and 10 mg/kg BW) and plasma and liver samples were extracted 7 days later. After sodium dodecyl sulfate polyacrylamide gel electrophoresis, the relative amount of VTG was determined by integrated optical density. VTG accounted for 23.6% of the total proteins in the control group, but this value decreased with increasing Al administration. Al reduced the concentrations of ALPP and Ca in a concentration-dependent manner and significant reduction occurred at Al concentrations greater than 5 mg/kg. The concentration of GPT increased in a concentration-dependent manner in all Al-administered rockfish. The concentrations of Al in the liver also increased, and HSI was decreased, in a concentration-dependent manner. These results suggest that Al inhibits $E_2$-induced VTG production by being toxic to hepatocytes in marine fish.

• 대한약침학회지
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• 제6권3호
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• pp.39-47
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• 2003

Background & Methods : In order to measure the acute and subacute toxicity of Vermilionum and it's anti-cancer effects, Sarcoma-180 abdominal cancer cells were injected intravenously. The following results were obtained after measuring the survival rate, toxicity of the NK cells, and IL- 2 productivity. Results : 1. It was impossible to measure $LD_{50}$ value in the acute toxicity test and no toxic effects were witnessed in the clinical observation. 2. No significant differences were shown in the weight changes between the experiment groups and the control group in the acute toxicity test. 3. No peculiar toxic effects were shown in the subacute toxicity test and the weight changes were insignificant between the experiment groups and the control group. 4. In measuring the survival rate after inducing abdominal cancer by Sarcoma-180, the experiment groups showed increased of 9.52% compared to the control group. 5. In measuring the activity of NK cells, no significant changes were shown between the experiment groups and the control group. 6. In measuring the productivity of IL-2, significant reduction was shown in the experiment groups compared to the normal group, but no significance was witnessed compared to the control group.

• Asian Pacific Journal of Cancer Prevention
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• 제15권16호
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• pp.6773-6779
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• 2014

Background: Nanotechnology opens new applications in many fields including medicine. Among all metallic nanoparticles, silver nanoparticles (silver NPS) have proved to be the most effective against a large variety of organisms including toxic cyanobacteria. Materials and Methods: Silver NPs were biosynthesized in vivo with different alga species namely, Spirulina piatensis, Chlorella vulgaris and Scenedesmus oh/iquus following two scenarios. First: by suspending a thoroughly washed algae biomass in 1 mM aqueous $AgN0_3$ solution. Second: by culturing them individually in culture media containing the same concentration of $AgN0_3$. Silver NPs were characterized using UV-Vis spectroscopy, transmission electron microscopy (TEM), energy dispersive analysis (EDX) and Fourier transform infra-red (FfIR) spectroscopy. The biosynthesized silver NPs were tested for cytotoxic activity against a cancer promoter cyanobacteruim Microcystis aeruginosa, considering effects on cell viability and chlorophyll content. Results: The surface plasmon band indicated the biosynthesis of silver NPs at ~400 nm. Transmission electron microscopy (TEM) revealed that the silver NPs had a mean average size below 100 nm. Energy-dispersive analysis X-ray (EDX) spectra confirmed the presence of silver element. FfIR spectral analyses suggested that proteins and or polysaccharides may be responsible for the biosynthesis of silver NPs and (-COO-) of carboxylate ions is responsible for stabilizing them. The toxic potentialities ofthe biosynthesized silver NPs against the cancer promoter cyanobacterium, Microcystis aeruginosa showed high reduction in viable cells count and the total chlorophyll content. Conclusions: The potential activity of the biosynthesized silver NPs from the studied algae species against Microcystis aernginosa cells is expected to be mainly mediated by the release of silver ions (Ag+) from the particle surface and bioactive compounds as indicated by FfIR analysis.

• Journal of Microbiology and Biotechnology
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• 제20권5호
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• pp.917-924
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• 2010

The practicability of transgenic tobacco engineered to express bacterial native mercuric reductase (MerA), responsible for the transport of $Hg^{2+}$ ions into the cell and their reduction to elemental mercury ($Hg^0$), without any codon modification, for phytoremediation of mercury pollution was evaluated. Transgenic tobacco plants reduce mercury ions to the metallic form; take up metallic mercury through their roots; and evolve the less toxic elemental mercury. Transformed tobacco produced a large amount of merA protein in leaves and showed a relatively higher resistance phenotype to $HgCl_2$ than wild type. Results suggest that the integrated merA gene, encoding mercuric reductase, a key enzyme of the bacterial mer operon, was stably integrated into the tobacco genome and translated to active MerA, which catalyzes the bioconversion of toxic $Hg^{2+}$ to the least toxic elemental $Hg^0$, and suggest that MerA is capable of reducing the $Hg^{2+}$, probably via NADPH as an electron donor. The transgenic tobacco expressing merA volatilized significantly more mercury than wild-type plants. This is first time we are reporting the expression of a bacterial native merA gene via the nuclear genome of Nicotiana tabacum, and enhanced mercury volatilization from tobacco transgenics. The study clearly indicates that transgenic tobacco plants are reasonable candidates for the remediation of mercurycontaminated areas.

• Toxicological Research
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• 제35권1호
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• pp.1-7
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• 2019

Mycotoxin contamination is a global phenomenon and causes a wide array of negative effects and other complications. This study focused on commonly found mycotoxins in Africa and the possible means of prevention or reduction of their contaminating effects. Mycotoxins are secondary metabolites of mold and fungi; they are generally toxic to living organisms. Hundreds of mycotoxins have been identified thus far, with some, such as aflatoxins, ochratoxins, trichothecenes, zearalenone, fumonisins, and patulin, considered agro-economically important. Several factors contribute to the presence of mycotoxins in food, such as climatic conditions, pest infestation, and poor harvest and storage practices. Exposure to mycotoxins, which occurs mostly by ingestion, leads to various diseases, such as mycotoxicoses and mycoses that may eventually result in death. In light of this, this review of relevant literature focuses on mycotoxin contamination, as well as various methods for the prevention and control of their prevalence, to avert its debilitating consequences on human health. Clear evidence of mycotoxin contamination is present in Africa, and it was therefore recommended that adequate prevention and control of these toxic substances in our food system should be encouraged and that appropriate measures must be taken to ensure food safety as well as the enhanced or long-lifespan of the African populace. Governments, research institutions, and non-governmental organizations should tailor the limited resources available to tackle mycotoxin prevalence, as these will offer the best prospects for successful development of a sustainable food system in Africa.

• 생약학회지
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• 제30권2호
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• pp.151-157
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• 1999

In order to find less toxic antiherpetic agents, the effect of natural quercetin on the plaque formation of herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) was studied in vitro in cell culture monolayers employing the technique of viral plaque reduction assay. Quercetin caused a concentration-dependent reduction in the plaque formation of herpesviruses. It also exhibited more potent antiherpetic activity on HSV-1 with effective concentration $(EC_{50})$ of $18.7\;{\mu}g/ml$ than on HSV-2 with $EC_{50}$ of $24.5\;{\mu}g/ml$. The combined antiherpetic effects of quercetin with nucleoside antiherpetic agents, acyclovir and vidarabine, were examined on the multiplication of these two strains of herpesviruses in Vero cells by the combination assay. The results of combination assay were evaluated by the combination index (CI) that was calculated by the multiple drug effect analysis. The combinations of quercetin with acyclovir on HSV-1 and HSV-2 showed more potent synergism with CI values of $0.19{\sim}0.89$ for 50%, 70%, 90% effective levels than those with vidarabine with CI values of $0.43{\sim}1.46$.