• Journal of Life Science
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• v.14 no.4
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• pp.547-552
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• 2004

The present study was carried out to investigate the potential acute toxicity of amitraz by a single subcutaneous dose in beagle dogs. The test chemical was administered subcutaneously to male beagle dogs at dose levels of 0, 2, 10, or 50 mg/kg. Mortalities, clinical findings, and body weight changes were monitored for the 14-day period following the administration. At the end of 14-day observation period, hematology, serum biochemistry, and gross postmortem examinations were examined. A single dog in the 50 mg/kg group was found dead on day 3 after treatment and the other two dogs in the group were sacrificed because of the severe clinical signs on day 7 after treatment. Treatment related clinical signs, including anorexia, edema, mass and abscess formation in the injection sites, depression, vomiting, lacrimation, decreased locomotor activity, ataxia, recumbency, paresis in the limbs, and/or moribundity were observed in all treatment groups in a dose-dependent manner. Decreased or suppressed body weight gain was also observed dose-dependently in all treated groups. In autopsy, dead animals in the 50 mg/kg group showed muscular hemorrhage and inflammation in the injection sites and congestion in the liver and kidney. The terminal sacrificed animals in the 10 mg/kg group also exhibited muscular hemorrhage and inflammation in the injection sites. Whereas, no treatment related effects on hematology and serum biochemistry were observed on day 14 after treatment at any dose tested. On the basis of the results, it was concluded that a single subcutaneous injection of amitraz to beagle dogs resulted in increased incidence of abnormal clinical signs and death, decreased body weight, and increased incidence of abnormal gross findings. In the experimental conditions, the $LD_{50}$value of amitraz was 22.3 mg/kg (95% confidence limit not specified) and the no-observed-adverse-effect level (NOAEL) was considered to be below 2 mg/kg for male dogs.

• Korean Journal of Agricultural Science
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• v.28 no.1
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• pp.33-40
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• 2001

The authors attempted to derive a comprehensive quantitative structure-toxicity relationships (QSTRs) between various physicochemical parameters of phenyl substituents in fungicidal phenylthionocarbamate derivatives and toxicity evaluated using TOPKAT calculation. On the basis of this approach we made preditions for toxicity values for not yet tested substances with respect to these systems. The results suggested that the optimal values, $(B_2)_{opt.}=1.54_{\AA}$(Ames mutagenicity), $(R)_{opt.}=0.16$ (car-cinogenicity of male rat), $(\pi)_{opt.)=0.16$ (carcinogenicity of male mouse), $({\varepsilon}LOMO)_{opt}=-0.52e.v.$ ($LD_{50}$ of rat oral), $(B_3){opt.}=1.54_{\AA}$(chronic LOAEU), $(logP)_{opt.}=4.25$ ($LC_{50}$ of Fathead minnow) and $({\sigma})_{opt}=-0.68$ ($EC_{50}$ of Daphnia magna) of phenyl substituents were strongly correlated with the acute and chronic toxicities.

• Journal of Microbiology and Biotechnology
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• v.17 no.8
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• pp.1394-1398
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• 2007

Acaricidal activity of the active constituent derived from Pyrus ussuriensis fruits against Dermatophagoides farinae and D. pteronyssinus was examined and compared with that of the commercial benzyl benzoate. The $LD_{50}$ value of the ethyl acetate fraction obtained from the aqueous extract of P. ussuriensis fruits was 9.51 and $8.59{\mu}g/cm^3$ against D. farinae and D. pteronyssinus, respectively. The active constituent was identified as quinone by spectroscopic analyses. On the basis of $LD_{50}$ values with quinone and its congeners, the compound most toxic against D. farinae was quinone ($1.19{\mu}g/cm^3$), followed by quinaldine (1.46), benzyl benzoate (9.32), 4-quinolinol (86.55), quinine (89.16), and 2-quinolinol (91.13). Against D. pteronyssinus, these were quinone ($1.02{\mu}g/cm^3$), followed by quinaldine (1.29), benzyl benzoate (8.54), 4-quinolinol (78.63), quinine (82.33), and 2-quinolinol (86.24). These results indicate that the acaricidal activity of the aqueous extracts can be mostly attributed to quinone. Quinone was about 7.8 and 8.4 times more toxic than benzyl benzoate against D. farinae and D. pteronyssinus. Additionally, quinaldine was about 6.4 and 6.6 times more toxic than benzyl benzoate against D. farinae and D. pteronyssinus, respectively. Furthermore, the skin color of the dust mites was changed from colorless-transparent to dark brown-black by the treatment of quinone. These results indicate that quinone can be very useful as potential control agents, lead compounds, or the indicator of house dust mites.

• Biotechnology and Bioprocess Engineering:BBE
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• v.9 no.6
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• pp.490-494
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• 2004

An efficacy test of PRP (polyribosylribitol phosphate)-TT (Tetanus toxoid) conjugate vaccines was carried out using BALB/c mice as an animal model by inoculating Haemophilus in­fluenzae type b (Hib) with a virulence enhancement factor (VEF). Three administrations of the conjugate vaccines at 2-week intervals elicited a significantly high level of PRP antibodies (P>0.0001). The protective activity of the PRP immunization was challenged with either Hib with iron dextran (Hib/) or with a combination of mucin and hemoglobin (Hibmh) as a VEF. The me­dium lethal dose $(LD_{50})$ for Hibmh and Hibiwas measured as 10 CFU (Colony Forming Unit) and $2.5{\times}10^{8}$ CFU respectively. Each immunized animal was challenged with five or ten times the $LD_{50}$ level of bacteria with a VEF. A significant difference in mortality between the immunized and control mice (P> 0.01) was observed with the Hibmh challenge inoculation but not with the Hibi challenge inoculation. These results show that a combination of mucin and hemoglobin was able to enhance the virulence of Hib in BALB/c mice to cause a lethal infection, thus suggesting that BALB/c mice introduced to this method can be an effective model animal for testing the protective efficacy of H. influenzae conjugate vaccines.

• Toxicological Research
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• v.19 no.3
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• pp.211-215
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• 2003

This study was carried out to investigate the acute oral toxicity of a crude extract derived from fruiting body of Phellinus gilvus (PGE) using male and female SD rats. Groups consisted of five male and female rats were treated with a single dose of the test substance intragastrically at 0, 500, 1,000, 2,000, and 5,000 mg/kgaj, respectively. Clinical signs, body weight change, and food and water consumption change were observed for 14 days after administration. No mortality or abnormal clinical signs in animals were shown during the observation period at the dose used in this study. Also there was no difference in net body weight gain, water and food consumption or gross pathological findings at terminal sacrifice among the groups of rat treated with different doses of the test substance. The results suggested that acute oral toxicity of PGE in rats is very low at the conditions employed in this study and $LD_{50}$ of PGE was estimated to be over 5,000 mg/$\textrm{m}{\ell}$ in both sexes of rats.

• The Journal of Korean Obstetrics and Gynecology
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• v.26 no.1
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• pp.59-68
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• 2013

Objectives: This study was conducted to investigate the acute toxicity of Pyungwi-san(Pingwei-san in Chinese) in ICR mice, according to KFDA and OECD guideline. Methods: In the present study, 15 male and female ICR mice administrated singly by gavage at dose levels of 0 and 2000 mg/kg of Pyungwi-san. During the experimental period, no treatment-related death was observed. There were no adverse effects on clinical signs, body weight, and gross findings at all treatment groups. Results: These results showed that the single oral adminstration of Pyungwi-san (Pingwei-san) did not cause any toxic effect at the dose levels of 2000 mg/kg in rats. Conclusions: Taken together, the median lethal dose($LD_{50}$) of Pyungwi-san (Pingwei-san) was considered to be over 2000 mg/kg body for both sexes.

• The Journal of Korean Obstetrics and Gynecology
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• v.26 no.4
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• pp.1-13
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• 2013

Objectives: In this study, it was carried out to evaluate the acute oral toxicity of Root of Polygala teunifolia Willd. in Sprague-Dawley (SD) rats. Methods: Male and female rats were administered orally with Root of Polygala teunifolia Willd. water extract of 1,000 mg/kg (low dosage group), 2,000 mg/kg (middle dosage group) and 4,000 mg/kg (high dosage group). We daily observed number of deaths, clinical signs and gross findings for 7 days. After 7 days, we measured body and organs weight. Also we analyzed hematological changes. Results: No dead SD rats and no clinical signs were found during the experiment period. Also other specific changes were not found between control and treated groups in hematology and serum biochemistry. But we found out histopathological changes in liver fat tissues of female. In addition, there were no significant changes of gross body and individual organs weight. Conclusions: These results suggest that water soluble extract of Root of Polygala teunifolia Willd. has not acute oral toxicity and oral $LD_{50}$ value was over 4,000 mg/kg in SD rats.

• Korean journal of applied entomology
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• v.42 no.3
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• pp.249-255
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• 2003

These studies were carried out to investigate fumigant, contact toxicity and repellency effects of 34 terpenes against acaricide susceptible the two-spotted spider mite, Tetranychus urticae. In addition, the efficacy was also tested against two acaricide-resistant strains. Two terpenes, isosafrole and safrole showed fumigant toxicity of 98.4%, at 10${\mu}\ell$/1 (air) concentration. LD$\_$50/ values of these two terpenes were 2.6${\mu}\ell$/1 and 4.3${\mu}\ell$l/1, respectively. Most terpenes showed low or no contact toxicity, except isosafrole showing 60.2% mortality against eggs. Hexanoic acid and limonene showed repellency effects of 79.1%, 87.8%, respectively, to the susceptible strain at concentration of 1,000 ppm in the lab conditions. Hexanoic acid (1,000 ppm) showed repellency effected of 77.8% and 83.3% to fenpropathrin and pyridaben resistant strains, respectively. However, limonene showed no repellency to the two resistant strains.

• Journal of Physiology & Pathology in Korean Medicine
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• v.22 no.6
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• pp.1439-1443
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• 2008

The objective of this study was to evaluate the acute toxicity of Taeumjowi-tang in rats. SPF Sprague-Dawley male and female rats were administered orally with Taeumjowi-tang extract of 2,500 mg/kg(low dosage group), and 5,000 mg/kg(high dosage group). We daily examined number of deaths, clinical signs, body weights and gross findings for 14 days. No dead animal and no significant changes of body weights were found during the experimental period. In addition, no differences were found between control and treated groups in clinical signs, hematology, serum biochemistry, and other findings. In conclusion, Taeumjowi-tang extract did not show any toxic effects, and oral LD50 value was over 5,000 mg/kg in SD rats.

• Genomics & Informatics
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• v.14 no.4
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• pp.230-233
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• 2016

Linkage disequilibrium (LD) is the non-random association between the loci and it could give us a preliminary insight into the genetic history of the population. In the present study LD patterns and effective population size (Ne) of three Korean cattle breeds along with Chinese, Japanese and Mongolian cattle were compared using the bovine Illumina SNP50 panel. The effective population size (Ne) is the number of breeding individuals in a population and is particularly important as it determines the rate at which genetic variation is lost. The genotype data in our study comprised a total of 129 samples, varying from 4 to 39 samples. After quality control there were ~29,000 single nucleotide polymorphisms (SNPs) for which $r^2$ value was calculated. Average distance between SNP pairs was 1.14 Mb across all breeds. Average $r^2$ between adjacent SNP pairs ranged between was 0.1 for Yanbian to 0.3 for Qinchuan. Effective population size of the breeds based on $r^2$ varied from 16 in Hainan to 226 in Yanbian. Amongst the Korean native breeds effective population size of Brindle Hanwoo was the least with Ne = 59 and Brown Hanwoo was the highest with Ne = 83. The effective population size of the Korean cattle breeds has been decreasing alarmingly over the past generations. We suggest appropriate measures to be taken to prevent these local breeds in their native tracts.