• Journal of Aquaculture
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• v.11 no.4
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• pp.429-435
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• 1998

This study compared acute ammonia toxicity in juvenile rockfish and red sea bream. Oxygen concentration affected ammonia toxicity to aquatic animals. Without aeration, the 96-hr $LC_50$ values of $NH_4^+$and un-ionhized ammonia for juvenil rockfish(3.6g, 6.6cm) were 2.61 and 0.09 mg/l, respectively. The 3-hr $LC_50$ values of $NH_4^+$ for the size of 1.9g (5.2cm) and 3.6g (6.6cm) rockfish, and 1.0g (3.8cm) and 2.0g (5.0cm) red sea bream without aeration were 3.96, 3.94, 4.35 and 3.75 mg/l, respectively. When oxygen level was low, larger fish were more susceptible to ammonia toxicity than smaller one because of stress resulted from low oxygen. However, with aeration, the 96-hr $LC_50$ values of $NH_4^+$ for the size of 1.2g (3.9cm) and 2.3g (5.1cm) red sea bream with aeration were 3.84 and 3.90mg/l, respectively. The 6-hr $LC_50$values of $NH_4^+$ for the size of 3.1g (5.9cm) and 6.2g (7.0cm) rockfish with aeration were 3.83 and 3.94 mg/l, respectively. When oxygen level was high, larger rockfish and red sea bream were less susceptible to ammonia toxicity than smaller ones. The 6 hr-or 96 hr-$LC_50$ values of $NH_4^+$for rockfish with reduced ammonia toxicity. In comparing 96 hr-$LC_50$ values of $NH_4^+$ and un-ionized ammonia for juvenil rockfish with those for juvenil red sea bream, the values for rockfish were lower than for red sea bream. This indicates that juvenile rockfish is more susceptible to ammonia toxicity than juvenile red sea bream.

• Korean Journal of Environmental Biology
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• v.21 no.2
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• pp.158-163
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• 2003

This study was conducted te evaluate the effect of organotin compounds on rotifer(Brachionus plicatilis), which is important as food organism of aqua-cultured fish and shellfish. To evaluate the texicities of tributyltin compounds such as tributyltin chloride (TBTC), tributyltin oxide (TBTO), tributyltin acetate (TBTA) and tributyltin benzoate (TBTB), and triphenyltin compounds such as triphenyltin chloride (TPTC), triphenyltin fluoride (TPTF), triphenyltin hydroxide (TPTB), the survival rates of rotifer exposed to these compounds were measured as the 96 hr-$LC_{50}$. Exposed concentrations Were from 0.5 to 8 bbp depending on compounds. Based on 96 hr-$LC_{50}$ Value, the Order of toxicity in TBTs was TBTA(1.1 ppb)>TBTC (2.0)>TBTB (3.3)>TBTO(5.6), and that in TPTs was TPTF (1.0)$\geq$TPTC(1.1)>TPTH(1.6). Triphenyltin compounds were slightly higher toxic than tributyltins. The toxicity is likely to depend on alkyl or aryl group other than halogen or the other substituted radicals.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.37 no.5
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• pp.380-384
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• 2004

The toxic impact of parathion on bagrid catfish (Pseudobagrus fulvidraco) juvenile was examined 96 hr $LC_{50}$ value of parathion estimated as 1 90 mg/L. Chronically, bagrid catfish were exposed for 30 days to concentrations of parathion, i.e. 63, 95, 190 and $380\;{\mu}g/L$, representing 3.3, 5.0, 10.0 and $20.0{\%}$ of the 96 hr $LC_{50}$. Survival rate was significantly affected by the concentration over $63\;{\mu}g/L$ after 10 days. Growth rate, specific growth rate (SGR) and feed efficiency were reduced in time as concentration dependent manner. Growth rates of the exposed groups were significantly reduced as $28.06-60.63{\%}$ to the control fish, SGR was decresed as $1.50-4.72{\%}$ and feed efficiency was declined as $6.10-11.90{\%}$. It can be concluded that if p. lulvidraco is chronically exposed to parathion over $63\;{\mu}g/L$ concentration, the physiological damages might affect growth factors of the fish.

• Environmental Analysis Health and Toxicology
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• v.21 no.2 s.53
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• pp.173-184
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• 2006

From the harmfulness expectation test conducted through a toxicity anticipation program, methylcyclohexane turned out to be harmful and simulative, but no carcinogenicity was anticipated. In a four-hour acute inhalation toxicity test, the result showed that lethal concentration ($LC_{50}$) was 3,750 ppm (15,054 mg/L), which was identified as a harmful substance on the basis of the harmful substance classification standard $2 of the Industrial safety and health law. methylcyclohexane fell under the category $4(2,500 substance from the GHS standard acute toxicity harmfulness classification. Also, from subchronic inhalation toxicity test that included 6 hours a day, five days a week, and for 13 weeks, we could observe weight, activity, long term weight, blood and blood biochemical influence from the exposure of test substance. No-observed effect level (NOEL) was determined below $100{\sim}400ppm$ inboth male and female. This material falls under the Category 2 ($50{\sim}250ppm/6hours/90days$) in the GHS (Globally Harmonized System) standard trace long-term whole body toxicity repeated exposure, and can be classified as a harmful substance in accordance with the Industrial Safety and Health Law harmful substance standard $NOEL{\leq}0.5mg/L/6hr/90day$ (rat).

• Korean Journal of Clinical Pharmacy
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• v.16 no.1
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• pp.69-74
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• 2006

날트렉손은 ${\mu}-opioid$ 수용체에 특이적이고 선택적으로 길항작용을 나타내어 마약이나 마약성 진통제의 강한 의존성 치료에 쓰일 뿐만 아니라, 알코올 의존성 치료에도 쓰이는 약물이다. 본 연구는 날트렉손 제제인 레비아 정 (50 mg tablet, 제일약품) 을 대조약으로 하여 시험약인 명인 제약의 트락손 50 mg정의 생물학적 동등성 평가를 하기 위해 22명의 건강한 지원자를 모집하였다. 지원자를 두 군으로 나누어 1정씩 투여하였고 $2{\times}2$ 교차시험을 실시하였다. 날트렉손의 혈장 중의 농도를 정량하기 위하여 발리데이션된 LC/MS/MS를 사용하였다. 채혈 시간은 투약 전 및 투약 후 0.25, 0.5, 0.75, 1, 1.5, 2, 3, 4, 6, 9, 12 시간에 걸쳐 시행하였다. 생물학적 동등성을 판정하기 위한 파라미터로 12시간까지의 혈장 중 농도 곡선 하 면적$(AUC_{12hr})$과 최고 혈중 농도 $(C_{max})$를 사용하였다. $AUC_{12hr}$의 평균은 $43.45ng{\cdot}hr/ml$ (시험약)과 $43.31ng{\cdot}hr/ml$ (대조약) 으로 관찰되었고, $C_{max}$의 경우 각각 12.01 ng/m1 (시험약)과 12.27 ng/ml (대조약)으로 관찰되었다. $AUC_{12hr}$의 경우 로그변환 한 평균치 차의 90%의 신뢰구간이 log0.95-log1.07이었고, $C_{max}$의 경우 log0.87-log1.14로 계산되어 두 항목 모두 log0.8-log1.25이어야 한다는 식품의약품 안전청과 FDA의 기준을 모두 만족시켰다. 이상의 결과를 종합하면 시험약 트락손 정 50mg 은 대조약 레비아 정 50 mg에 대하여 생물학적으로 동등한 것으로 판정되었다.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.6
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• pp.628-632
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• 2009

In order to estimate acute toxicity of various heavy metals on mysid, Neomysis japonica, the experiments were conducted by renewal bioassay method at $20\pm0.5^{\circ}C$ and $30\pm0.3$ psu salinity. The 96 hr $LC_{50}$ of Neomysis japonica exposed to cadmium, copper, zinc, arsenic, lead and chromium were $90.4\;{\mu}g/L$, $82.3\;{\mu}g/L$, $646.1\;{\mu}g/L$, $1488.5\;{\mu}g/L$, $1758.8\;{\mu}g/L$ and $1609.6\;{\mu}g/L$, respectively, and were ranked in order of toxicity: copper > cadmium > zinc > arsenic > chromium > lead.

• Journal of Pharmaceutical Investigation
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• v.38 no.1
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• pp.73-78
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• 2008

To evaluate the bioequivalence of two ramipril formulations, a standard 2-way randomized cross-over study was conducted in twenty-six healthy male Korean volunteers. A single oral dose of 10 mg of test formulation $Ramiprin^{(R)}$ (tablet) or reference formulation Tritace $Protect^{(R)}$ (tablet) was administered with one-week washout period. Plasma concentrations of ramipril were assayed over a period of 12 hr with a well validated method using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). The values of area under the plasma concentration-time curve, from time zero to last sampling time $(AUC_t)$ and from time zero to time infinity $(AUC_{inf})$ were $77.45{\pm}44.78\;and\;78.96{\pm}45.64$ for test, and $70.30{\pm}42.27\;and\;71.99{\pm}43.55ng\;hr/mL$ for reference formulation, respectively. Similarly, maximum concentration $(C_{max})$ and elimination half-life $(t_{1/2})$ were $65.61{\pm}19.96ng/mL$ and $2.15{\pm}0.75hr$ for test, and $63.63{\pm}25.50ng/mL$ and $2.16{\pm}0.73hr$ for reference formulations, respectively. Time to reach maximum concentration $(T_{max})$ for the test and the reference, were $0.51{\pm}0.22hr\;and\;0.52{\pm}0.18hr$, respectively. The parametric 90% confidence intervals on the mean of the differences between the two formulations (test-reference) of the log-transformed values of $AUC_t\;and\;C_{max}$ were 1.03 to 1.19 and 0.98 to 1.17, respectively. The overall results indicate that the two formulations are bioequivalent and can be prescribed interchangeably.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.1
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• pp.87-97
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• 1995

Acute and chronic toxicity of phenol on the mortality, long-term survival and respiration rates of the mysid, Archaeomysis kokuboi adult and juvenile were examined. This experiment was condurted by static bioassay procedure with the different salinity at $25^{\circ}C$ In lethal test, the test animals were exposed to 6 different phenol concentrations to determine $LC_{50}$ and I$LT_{50}$ (median lethal concentration and time) values. The $LC_{50}$ values with the exposure time for the mysid adult ranged from 31.31ppm to 1.49ppm phenol and for the mysid juvenile ranged from 6.90ppm to 0.26ppm in all experimental groups. Mortality was increased with the decrease of salinity, The $96hr-LC_{50}$ values at 16, 24 and $32\%o$ salinity for the mysid adult were 1.49, 2.71 and 4.53ppm phenol, white the values for the mysid juvenile were 0.26, 0.56 and 0.71ppm, respectively. The ratios of $96hr-LC_{50}$ values for the mysid adult to those for the mysid juvenile at 16, 24 and $32\%p$ salinity were 5.73, 4.84 and 6.38, respectively. The mysid juveniles were more sensitive to phenol than the mysid adults. Compared $LT_{50}$ values for the mysid adult with those for the mysid juvenile, the $LT_{50}$ values for the mysid adult ranged from 384.7 to 29.0 hours at 1.7-127ppm phenol concentrations and for the mysid juvenile ranged from 132.2 to 18.7 hours at 0.5~6.Oppm phenol concentrations. The lowest $LT_{50}$ values for the mysid adult and juvenile were showed at the combination of the highest experimental concentration of phenol and the lowest experimental salinity. The mysid juveniles showed lower $LT_{50}$ values than those of adults. The chronic effects of phenol on the mysid at the sublethal effective concentration of phenol were lower in the $32\%o$ salinitr group than 16 or $24\%o$ salinity groups. Oxygen consumption rates of the mysid adult were decreased with the increase of phenol concentration and exposure time, and decreased significantly in lower salinity at the same concentration or phenol.

• Journal of Life Science
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• v.26 no.4
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• pp.387-397
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• 2016

The purpose of this study was to determine if heat shock proteins are involved in autophagy in skeletal muscle. We used the autophagy flux strategy, which is an LC3 II/p62 turnover assay conducted with and without an autophagy inhibitor, to determine whether 17-DMAG (an Hsp90 inhibitor/Hsp72 activator) stimulates autophagy in skeletal muscle. We treated C2C12 cells with 17-DMAG (500 nM) for 24 hr with and without the autophagy inhibitor (Bafilomycin A1, 200 ng/ml), and we injected C57BL/6 mice i.p. with 17-DMAG (10 mg/kg) daily for 7 days with and without colchicine as an autophagy inhibitor (0.4 mg/kg/day, administered on the last 2 days). C2C12 myotubes and tibialis anterior muscles were harvested for analysis of mTOR-dependent autophagy signaling pathway proteins and autophagic marker proteins (p62 and LC3 II) by Western blot analysis. The blots showed that 17-DMAG upregulated hsp72 and decreased Akt protein levels and S6 phosphorylation in C2C12 cells. However, an in vitro autophagic flux assay demonstrated that 17-DMAG did not increase LC3 II and p62 protein concentrations to a greater extent than Bafilomycin A1 treatment alone. Similarly, 17-DMAG increased Hsp72 protein levels and decreased the expression of Akt and the phosphorylation of S6 in mouse skeletal muscle. However, unlike the response seen in C2C12 myotubes, the p62 protein levels were significantly decreased in 17-DMAG-treated mouse skeletal muscle (~50%; p<0.05). The LC3 II protein levels in 17-DMAG-treated mice were increased ~2-fold more when degradation was inhibited by colchicine (p<0.01). This suggests that 17-DMAG stimulates basal autophagy in skeletal muscle but is not found in C2C12 myotubes.

• The Korean Journal of Pesticide Science
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• v.19 no.3
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• pp.255-263
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• 2015

Promoting the organic farming, much of the plant extracts used for controlling pests and fungi have been imported from China, India and Myanmar. But, it is so worrisome that aquatic animals such as muddy loach inhabiting in paddy field and common carps in river exposed to the pests and fungi likely be harmed. This study was conducted in order to evaluate the risks of aquatic animals influenced by the three plant extracts, i.e. Sophora flavescens, Azadirachta indica and Derris elliptica. The toxicities of common carp (Cyprinus Carpio), muddy loach (Misgurnus anguillicaudatus) and PEC (Predicted environmental concentration) exposed to the three plant extracts were estimated by the typical spray volume method. Risks were determined by the toxicity value as 48-hr $LC_{50}$ (Lethal concentration, median) or NOEC (No observed effect concentration) into PEC. 48-hr $LC_{50}$ of Common carp and NOEC by Sophora flavescens extracts was 7.9 and 6.2 mg/L, 26.8 and 21.8 mg/L by Azadirachta indica extracts and 47.0 and < 24.0 mg/L by Derris elliptica extracts, respectively. 48-hr $LC_{50}$ of Muddy loach and NOEC by Sophora flavescens extracts was 16.9 and 10.0 mg/L, 35.6 and 30.0 mg/L by Azadirachta indica extracts, and 73.9 and < 40 mg/L by Derris elliptica extracts, respectively. Therefore, acute toxicities of the three plant extracts for aquatic animals were proved to be very low level. PEC of Sophora flavescens extracts in paddy, drainage and river water was 68.0~3.0, 11.33~0.50 and 3.0~0.0018 mg/L, respectively. TER of Sophora flavescens extracts in the three water was 0.2~5.6, 1.5~33.8 and 2.6~4388.9, respectively. PEC of Azadirachta indica extracts in paddy, drainage and river water was 90.9~1.2, 15.2~0.2 and 4.8~0.00075 mg/L, respectively. TER of Azadirachta indica extracts in the three water was 0.4~29.7, 2.3~178.0 and 4.5~35733.3, respectively. PEC of Derris elliptica extracts in river water was 0.0063 mg/L. TER of Derris elliptica extracts in river water was 5222~15667.