• Advances in Traditional Medicine
• /
• v.6 no.1
• /
• pp.21-26
• /
• 2006

The ethanolic extract of Fleurya interrupta Gaud, (Urticaceae) was tested for its possible neuropharmacological effects on experimental animals, For the primary neuropharmacological screening of this plant, the ethanolic extract of its aerial parts was subjected to preliminary evaluation for acute toxicity, antinociceptive activity and central nervous system (CNS) activities. At the doses of 125 and 250 mg/kg, the extract significantly (P < 0.01 and P < 0. 001) and dose-dependently increased the frequency of acetic acid induced writhing in mice. In the pentobarbitone induced sleeping time test, the extract at the above dose levels, significantly and dose-dependently decreased the pentobarbitone induced sleeping time (P < 0.001) and increased the time for onset of sleep (P < 0.001) in mice. In the open field and hole cross tests, test animals showed an increase in their movement in the both tests from the 2nd observation period (30 min) and persisted throughout the entire experimental period (240 min). These results of the extract may attribute a stimulating action on the CNS. On the basis of these findings, it can be assumed that the extract exerts its stimulating effect on the CNS in mice by interfering with the cortical function or increasing the effect of some CNS stimulating neurotransmitters.

• Toxicological Research
• /
• v.14 no.2
• /
• pp.183-191
• /
• 1998

It has been reported that 50~70% of child asthma, bronchial asthma in adult, and allergic rhinitis are caused by house dust mite. The antigen extracted from house dust mite has been used for effective treatment against allergic diseases and for clinical test. This house dust mite antigen has been entirely imported from abroad. However, the composition and content of all the antigen imported vary from a brand to other brand. Thus, we need to standardize the composition and content of the antigen by developing it domestically. We proceeded pre-clinically general pharmacological test and toxicological test that are required for the eventual human use by utilizing the house dust mite cultured in Korea. In order to obtain information on general pharmacological tests such as its toxic signs in tissues or organs which are mainly affected, we examined the effect of house dust mite on the tensions of the isolated tissues and heart rates of cardiac muscle by recording with force displacement transducer of polygragh (Glass Model 7). We determined lethality of antigen extracted from house dust mite in mice and guinea pigs. We examined acute and subacute toxicity by administrating house dust mite extract of 500, 100, 20 times of the expected clinical dose. In male and female mice and guinea pigs, given a sigle intraperitoneal dose of antigen, $LD_{50}$ values were over 5.0 $\textrm{m}{\ell}$/kg, respectively. In animals administrated with house dust mite, there were no significant change of clinical symptom, body weight, food consumption, water consumption, eye examinations, urinalysis, blood biochemistry, and histopathological examinations in any animals tested. We found no toxic effect of this house dust mite. These results show that the house dust mite cultured by us could be used in the development of medicine against allergic diseases caused by the antigen of house dust mite.

• Korean Journal of Agricultural Science
• /
• v.43 no.2
• /
• pp.205-214
• /
• 2016

A drought-tolerant transgenic rice (Agb0103) was developed using a pepper methionine sulfoxide reductase (CaMsrB2) under the control of rice Rab21 promoter with a selection marker, the phosphinothricin acetyltransferase (PAT) gene. Commercialization of genetically modified (GM) crops will require the evaluation of risks associated with the release of GM crops. With the potential problems associated to GM crops safety testing, the investigation of their effects on non-target organisms is necessary for environmental risk research. This study was carried out to assess acute toxicity of a GM crop using the water flea (Daphnia magna) for non-target organism risk evaluation. The effect of acute toxicity on Daphnia magna of Agb0103 rice and a non-GM rice, Ilmibyeo, were investigated at different concentrations (0, 625, 1,250, 2,500, 5,000, and 10,000 mg/L). The Agb0103 rice used for the test was confirmed to express the CaMsrB2/PAT gene by the PCR and ELISA. Daphnia magna feeding tests showed no significant differences in cumulative immobility or abnormal response with either Agb0103 rice or non-GM rice. The 48hr-EC50 values showed no difference between Agb0103 rice (2243 mg/L) and non-GM rice (2694 mg/L). These results suggest that there is no significant difference in toxicity to Daphnia magna between Agb0103 rice and its non-GM counterpart.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.25 no.4 s.34
• /
• pp.145-154
• /
• 1999

A novel retinol derivative, polyethoxylated retinamide(Medimin A) was synthesized, as an anti-aging agent. Collagen synthesis, skin permeation, stability, and toxicity of Medimin A were evaluated and compared with those of retinol and retinyl palmitate. In vitro collagen synthesis was evaluated by quantitative assay of $[^3H]-proline$ incorporation into collagenase sensitive protein in fibroblast cultures. For in vitro skin permeation experiments, Franz diffusion cells(effective diffusion area: 1,766 $cm^2$) and the excised skin of female hairless mouse aged 8 weeks were used, The stabilities of retinoids were evaluated at two different temperature($25^{\circ}C\;and\;40^{\circ}C$) and under UV in solubilized state and in O/W emulsion. To estimate the safety, acute oral toxicity, acute dermal toxicity, primary skin irritation, acute eye irritation and human patch test were performed. The effect of Medimin A on collagen synthesis was similar to that of retinol. The skin permeability of Medimin A was higher than those of retinol and retinyl palmitate. The Medimin A was more stable than retinol and retinyl palmitate. Medimin A was nontoxic in various toxicological tests. These results suggest that Medimin A would be a good anti-aging agent for enhancing bioavailability and stability.

• Korean Journal of Agricultural Science
• /
• v.47 no.4
• /
• pp.791-802
• /
• 2020

Theoredoxin (TRX) transgenic soybeans were developed using the human Theoredoxin gene under the control of the ��-conglycinin promoter with a selection marker, the phosphinothricin acetyltransferase (PAT) gene. This study was done to assess the acute toxicity of a genetically modified (GM) soybean using the fresh water planktonic crustacean Daphnia magna. The acute toxicity effect of the TRX soybean and non-GM soybean (Gwangan) on D. magna was investigated at different concentrations (0, 156, 313, 625, 1,250, 2,500, and 5,000 mg·L-1). The TRX soybean used for the test was confirmed to express the TRX/PAT genes by PCR and enzyme-linked immunosorbent assay (ELISA). D. magna feeding tests showed no significant differences in the cumulative immobility or an abnormal response with either the TRX soybean or non-GM soybean. The feeding study showed a similar abnormal response and cumulative immobility of the D. magna between the TRX soybean and Gwangan treatments. Additionally, the 48 h-EC50 values for the TRX and Gwangan soybeans were 755.6 and 778 mg·L-1, respectively. The soybean NOEC (no observed effect concentration) value for D. magna was suggested to be 156 mg·L-1. These results suggest that there is no significant difference in toxicity to Daphnia magna between the TRX soybean and its non-GM counterpart.

• Biomedical Science Letters
• /
• v.25 no.1
• /
• pp.54-59
• /
• 2019

Hepatitis refers to inflammation of hepatocytes and liver tissue, and is mainly caused by viruses, alcohol, and drugs. Forsythiae Fructus has traditionally been used as a diuretic, anti-inflammatory and antipyretic. Research on rengyolone, a bioactive substance extracted from Forsythiae Fructus, is rarely found in Korea and abroad. First, an acute animal toxicity test for rengyolone was conducted for the animal experiment. 4 week-old SD rats were injected intraperitoneally with acetaminophen for 2 weeks to induce chronic liver inflammation. Rengyolone was orally administered into two groups during 4 weeks: pre-inflammatory group and post-inflammatory group. Oral doses were also divided into 1 mg/kg and 5 mg/kg. Liver function tests (ALT, AST, ALP), western blot analysis of liver tissue, and level of inflammatory cytokine were performed to evaluate the improvement of hepatitis. Experimental results showed that rengyolone inhibited the development of acute inflammation and thus could reduce hepatitis symptoms.

• Korean Journal of Environmental Agriculture
• /
• v.7 no.2
• /
• pp.124-129
• /
• 1988

Prolonged aquatic toxicity tests (7-days) of six pesticides to the freshwater fish Oryzias latipes were performed to confirm the adequacy of the exposure times, 48-hr or 96-hr, which has been required by the protocols for the aquatic acute toxicity test. The toxicity curves were plotted for each chemical, and the significance of the difference between lethal threshold concentrations and 48-hr or 96-hr LC50's was analysed statistically. The lethal threshold concentrations of butachlor, fenobucarb, and chlorothalonil were clearly defined on the 5th day, 2nd day, and 2nd day at 0.53mg/1, 10.3mg/l, and 0.085mg/1, respectively. But the toxicity curves of alachlor, diazinon, and iprobenfos continued with no threshold for 7 days. Four out of six test pesticides failed to show the threshold concentration during the 96-hr exposure time. Therefore, the results of the acute toxicity test using 48-hr or 96-hr exposure time would not describe the ideal toxicity of pesticides. It is recommended that the prolonged exposure should be continued long enough to define the threshold adequately.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.17 no.3
• /
• pp.181-191
• /
• 2007

With the 2-Butanethiol, which is an unidentified inhalation toxic material, acute inhalation toxicity was tested with SD rats. The $LC_{50}$ was evaluated to be 2,500 ppm (9.22 mg/L) or higher which falls under the criteria of acute toxicity Category 3 (500<$LC_{50}$<2,500 ppm) in the Industrial Safety and Health Act. In the subchronical inhalation toxicity test by 0, 25, 100, and 400 ppm, 6 hours a day, 5 days a week, for 13 weeks repeated exposure, though no death or particular clinical presentation was observed, in the female 25 and 400 ppm group, including weight change, and in each concentration group including 400 ppm, change of feed rate, eye stimulation, motility change in male group, and lesions in blood and blood biochemical were observed. In the internal organs weight, 25, 100, and 400 ppm groups in male and 400 ppm group in female showed significant (p<0.05) changes in kidney, liver, thymus, and lung. In the pathological tissue test, severe cortical tubular hyaline droplets were observed in the male 400 ppm group, and all male rats of 400 ppm group and 2 female individuals showed tubular degeneration/regeneration accompanied with pigmentation, showing that the target organs of inhalation exposure of 2-Butanethiol are spleen, kidney, nasal cavity, and adrenal. Through the tests, the NOEL of 2-Butanethiol was evaluated to be 25 ppm (0.092 mg/L) or less for both male and female.

• Korean Journal of Environmental Agriculture
• /
• v.36 no.2
• /
• pp.80-86
• /
• 2017

BACKGROUND: Pesticides is exposed in an aquatic environment and effected to benthic animals. Especially, sediment-associated pesticides is required for determination of sediment toxicity on aquatic organisms. This study was conducted to evaluate the impact of six pesticides (chlorfluazuron, difenoconazole, dithianon, flufenoxuron, flutianil, pendimethalin) on Chironomus riparius in aquatic ecosystems. METHODS AND RESULTS: Chlorfluazuron, difenoconazole, dithianon, flufenoxuron, flutianil and pendimethalin were used as a model compounds, which have a sediment-associated potential ($K_{oc}$>3). Acute and chronic toxicity tests on Chironomus riparius were performed at six concentrations of each pesticide with four replicates of each based on OECD test guideline 235 and 218. The calculated 48-h $EC_{50}$ values of chlorfluazuron, flutianil, pendimethalin, difenoconazole, dithianon and flufenoxuron were 6.72, 2.55, 2.27, 0.77, 0.30 and 0.11 mg/L, respectively. Flufenoxuron was the lowest 48-h $EC_{50}$ value in this study. The No Observed Effective Concentration (NOEC) and the Lowest Observed Effect Concentration (LOEC) of flufenoxuron for Chironomus riparius in 28-days test were 30 and $60{\mu}g/kg$, respectively. CONCLUSION: Pesticides of the sediment-associated have the potential effect for Chironomus riparius in aquatic ecosystems. Therefore, sediment toxicity assessment of these pesticides should be further investigated to evaluate the impact to benthic organisms.

• Environmental Analysis Health and Toxicology
• /
• v.31
• /
• pp.26.1-26.9
• /
• 2016

Objectives Korea's Act on the Registration and Evaluation of Chemicals (K-REACH) was enacted for the protection of human health and the environment in 2015. Considering that about 2000 new substances are introduced annually across the globe, the extent of animal testing requirement could be overwhelming unless regulators and companies work proactively to institute and enforce global best practices to replace, reduce or refine animal use. In this review, the way to reduce the animal use for K-REACH is discussed. Methods Background of the enforcement of the K-REACH and its details was reviewed along with the papers and regulatory documents regarding the limitation of animal experiments and its alternatives in order to discuss the regulatory adoption of alternative tests. Results Depending on the tonnage of the chemical used, the data required ranges from acute and other short-term studies for a single exposure route to testing via multiple exposure routes and costly, longer-term studies such as a full two-generation reproducibility toxicity. The European Registration, Evaluation, Authorization and Restriction of Chemicals regulation provides for mandatory sharing of vertebrate test data to avoid unnecessary duplication of animal use and test costs, and obligation to revise data requirements and test guidelines "as soon as possible" after relevant, validated replacement, reduction or refinement (3R) methods become available. Furthermore, the Organization for Economic Cooperation and Development actively accepts alternative animal tests and 3R to chemical toxicity tests. Conclusions Alternative tests which are more ethical and efficient than animal experiments should be widely used to assess the toxicity of chemicals for K-REACH registration. The relevant regulatory agencies will have to make efforts to actively adopt and uptake new alternative tests and 3R to K-REACH.