• Journal of Microbiology and Biotechnology
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• v.15 no.6
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• pp.1197-1206
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• 2005

Vibrio vulnificus is an opportunistic pathogen that causes a septicemia and expresses numerous virulence factors, in which luxS and smcR are genes encoding for components responsible for quorum-sensing regulation. In the present study, null mutants were constructed with lesions in each or both of these two genes from the V. vulnificus Vv$\Delta$Z strain, which is a lacZ$^{-}$ and chloramphenicol/streptomycin-resistant derivative of the wild-type ATCC29307 strain, and their phenotypes related to virulence were compared with those of the parental cells. $LD_{50}$ and histopathological findings of luxS-, smcR-, or luxS- smcR- deficient mutant were not different from those of the parent strain, a lacZ-deficient streptomycin-resistant strain in mice. However, time of death in mice was delayed, and numbers of bacteria survived in bloodstream after intraperitoneal injection in mice were decreased by mutation, especially luxS and smcR double mutant (VvSR$\Delta$ZSR). These phenomena were supported by increased serum sensitivity and delayed bacterial proliferation in both murine blood and iron-restricted medium. These results suggest that the luxS and luxR homologous genes in V. vulnificus could playa role in bacterial survival in host by enhancing proliferation and adjusting to changed environment.

• The Korean Journal of Pesticide Science
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• v.20 no.4
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• pp.355-360
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• 2016

The insecticidal activities of the essential oils of Artemisia vulgaris, Achillea millefolium, Anethum graveolens, Cimicifuga heracleifolia, Citrus paradisi, Chrysanthemum indicum, Eucalyptus dives, Neroli bigard, Nigella sativa, and Ruta graveolens against stored-grain insects, Plodia interpunctella and Tribolium castaneum larvae and adults were evaluated using fumigant and contact bioassays. Based on the $LD_{50}$ values in fumigant bioassay, A. millefolium ($0.12{\mu}g/cm^3$) and A. graveolens ($93.14{\mu}g\;cm^{-3}$) oil were most effective against P. interpunctella and T. castaneum adults. In addition, N. bigard ($139.11{\mu}g\;cm^{-3}$) and A. graveolens ($52.87{\mu}g\;cm^{-3}$) oil exhibit strong insecticidal activities against P. interpunctella and Tribolium castaneum larvae in contact bioassay. These results indicate that A. millefolium, A. graveolens, N. bigard, and A. graveolens oils could be effective natural acaricides for managing stored-grain insects, P. interpunctella and T. castaneum.

• Journal of Food Hygiene and Safety
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• v.7 no.2
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• pp.83-89
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• 1992

This study was perfonned to investigate effectiveness eness on the gastritis and gastric lesion with the methanol extract of the flower buds of Eugenio caryophyllata. The extract was fractionated with hexane, chIorofonn, ethyl acetate, butanol, followed by bioassay Oil antigastritis. The ethyl acetate and the buthanol fraction reduced significantly HCI.ethanol induced gastric lesion at the dose of 165 and 215 mg/kg, p.o., respectively. These results may indicate that remarkably.effective are ethyl acetate and butanol fractions in HCI-ethanol induced gastric lesion. Howeever, the fractions didn't exhibit any inhibition of gastric secretion and acid output. The buthanol fraction reduced significantly the acetic acid induced ulcer at a daily dose of 215 mg/Kg, p.o., given for 10 days. These result showed considerable inhibit of acetic acid induced ulcer without inhibition of indomethacin induced gastric lesion. The methanol extract showed low acute toxicity with minimum lethal dose of more than 3000 mg/kg, p.o. in mice. In conclusion, Eugenia F10s exhibited antigastric activity which might be attributable to inhibition of gastric secretion. It is indicated that activie component may be present in the buthanol fraction.

• The Journal of the Korean Society for Microbiology
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• v.22 no.1
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• pp.1-8
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• 1987

Hantaan virus(HV) 76-118 strain was inoculated into suckling ICR mice by intra-nasal route with an inoculum of $10LD_{50}$. Mortality was 65% at the 3rd week after inoculation, but declined to 35% at the 4th week. Infectivity was determined by the measuring immuno-fluorescent antibody in sera. The peak of infectivity was 80% at the 4'th week after inoculation. Viremia was reached peak level of $1.7{\times}10^4\;PFU/ml$ by day 10. Immunofluorescent antibody and neutralizing antibody appeared by 2 weeks and 15-17 days respectively, but achieved similar titer by 35 days. By using a monoclonal antibody to HV 76-118, viral antigens were initially detected in inguinal and axillary lymph node by 2 days. Viral antigens in bone marrow and lung were delayed much more than in those of lymph node. These were similar with those of intra-peritoneal and intra-muscular route. Immune complex against IgG, IgM and C3 appeared by 16 days, 14 days, and 18 days respectively. The pattern of immunofluorescence in the basement membrane of glomeruli was diffuse membranous. Spotted pattern was also observed in the tissue stained with anti-mouse C3 antibody. By 20 days, control tissue was also shown immune complex in the glomeruli.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.50 no.5
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• pp.534-540
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• 2017

This study was conducted to determine the circadian rhythm and the effect of starvation for the health assessment of olive flounder Paralichthys olivaceus, reared under 12:12 LD (light:dark) cycle and fed 1% of their body weight once a day. The blood collection was implemented from 10 fish every 3 hours for a day, and analyzed to serval health parameters of the experimental fish. Plasma cortisol, glucose and total protein concentration reflected diel rhythms with high level of photophase and low level of scotophse despites of glutamic oxalacetic transaminase (GOT) and glutamic pyruvate transaminase (GPT) showing no rhythmicity, while electrolyte (sodium, potassium and chloride ion) concentrations arrived at the peak 18 hour and then slowly down. In the experiment of starvation, the result showed that there were no significant differences of the health parameters between the starved group and the fed. In short, our findings described the existence of circadian cortisol with glucose in flat fish, and indicated that the starvation does not almost affect the health of fish.

• Journal of Pharmacopuncture
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• v.15 no.3
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• pp.48-52
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• 2012

Objective: This study was performed to analyze the single-dose toxicity of Aconitum kusnezoffii Reichb. pharmacopuncture (AKRP). Methods: All experiments were conducted at the Korea Testing & Research Institute (KTRI), an institute authorized to perform non-clinical studies, under the regulations of Good Laboratory Practice (GLP). Twenty (20) Sprague-Dawley rats were chosen for the pilot study. The animals were divided into four groups of five animals per group: group 1 (G1) being the control group with each animal receiving an injection of 0.3 ml of saline and groups 2, 3, and 4 (G2, G3, and G4) being the experimental groups with each animal receiving an injection of 0.1, 0.2 or 0.3 ml of AKRP, respectively. This study was conducted with the approval of the Institutional Animal Ethics Committee. Results: No deaths occurred in any of the 4 groups, and the $LD_{50}$ of AKRP administered via IV was higher than 1.77 ml/kg. Some changes in the weights of the male rates were observed between the control group and the experimental groups, but no significant differences were noted in the weights of the female rats. To check for abnormalities in organs and tissues, we stained representative sections of each specified organ with Hematoxylin & Eosin for light microscopic examination. The results showed no significant differences in any of the organs or tissues. Conclusions: The above findings suggest that Aconitum kusnezoffii Reichb. pharmacopuncture is a relatively safe treatment. Further studies on the subject should be conducted to yield more concrete evidence.

• The Journal of Korean Medicine
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• v.32 no.3
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• pp.18-24
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• 2011

Objective: Leejung-tang (Rechu-to in Japanese) is a traditional Korean herbal formula used for treatment of gastrointestinal disorders such as vomiting, stomach pain, chronic gastritis and gastrointestinal ulceration. The present study was carried out to investigate the potential acute toxicity of Leejung-tang water extract (LJT) by a single oral dose in Crl:CD (SD) rats in compliance with current guidelines. Methods: In the preliminary study, there were no adverse effects such as death, clinical signs, and body weight changes at dose levels of 500, 1000, and 2000 mg/kg/day body weight. Based on the results, a dose of 2000 mg/kg was selected as the toxicological limited dose. LJT was administered once by gavage to male and female rats at dose levels of 0 and 2000 mg/kg bodyweight. During the study period, mortalities, clinical findings, and body weight changes were observed for 14 days following the administration. On day 14 after the treatment, the animals were sacrificed by carbon dioxide overdose and complete gross postmortem examinations were performed. Results: In present study, no treatment-related deaths were observed. There were no adverse effects on clinical signs and body weight changes. In addition, there were no observed gross findings in all groups except for a kidney cyst in the 2000 mg/kg/day female group. Conclusion: The results indicated that LJT did not induce toxic effects at a dose level up to 2000 mg/kg in rats and its median lethal dose ($LD_{50}$) was considered to be over 2000 mg/kg/day body weight for both genders.

• Biomolecules & Therapeutics
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• v.8 no.1
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• pp.84-92
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• 2000

This Study was conducted to assess the single dose toxicity of DA-125, a new anthracycline anti-cancer agent, in rats and mice. The Drug was administered once intravenously to both sexes of rats and mice. Then followed a 14-day period of observation. The $LD_{50}$ Values (95% confidence limit) were estimated to be 60.9 mg/kg (57.5~64.3 mg/kg) for male rats and 60.2 mg/kg (56.2~64.5 mg/kg) for female rats, and 85.8 mg/kg (81.0~90.9 mg/kg) for male mice and 84.5 mg/kg (78.2~91.9 mg/kg) for female mice. Both sexes of rats and mice given the drug revealed the clinical sign of decreased locomotor activity, emaciation, hair loss, red-dish brown urine, salivation, and watery diarrhea. In addition, body weight from the next day to the 7th day tended to be decreased slightly in rats and mice treated with DA-125. Death occurred from the next day after administration to the 12th day. Macroscopically, congestion of gastrointestinal organ, lung, and adrenal glands were found in both sexes on the dead rats and mice. Histopathological examination of dead rats manifested atrophy of spleen, hypoplasia of bone marrow, hypcplasia and necrosis of lymphocyte in thymus, atrophy of villi in small intestine (duodenum, jejunum, and ileum), hyperplasia of granular epithelium in small intestine, degeneration of germinal epithelium in testis, defer oration of tubular epithelium in kidney, and vacuolation and myolysis of myocardium in heart. Histopathological examination of dead mice revealed hypoplasia of spleen and mesenteric lymph node, local necrosis of liver, atrophy of villi in small intestine, hyperplasia of glandular epithelium in small and large intestine, degeneration of tubular in kidney, degeneration of germinal cells in testis, and slight vacuolar degeneration of myocardium in heart.

• YAKHAK HOEJI
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• v.38 no.3
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• pp.250-264
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• 1994

Omeprazole(OMZ)-cholestyramine(CHL) and various OMZ-Dowex resin complexes were prepared by reaction between OMZ and activated resins in 0.1N NaOH solution. And their physical properties were tested by means of infrared(IR), differential scaning caloimeter(DSC), X-ray diffraction. Chemical stability of OMZ-CHL was increased markedly compared with OMZ and the decomposition of OMZ-CHL followed the pseudo first-order kinetics and the rate constants were $2.743{\times}10^{-4}/day$ at $20^{\circ}C$, $7.83{\times}10^{-3}day^{-1}$ under 80% RH and $1.68{\times}10^{-2}day^{-1}$ under UV radiation, respectively. On the other hand, the rate constants of OMZ were $2.996{\times}10^{-4}day^{-1}$ at $20^{\circ}C$, $1.17{\times}10^{-2}day^{-1}$ under 85% RH, and $4.07{\times}10^{-2}day^{-1}$ under UV radiation, respectively. The rates of dissolution of OMZ-CHL bulk and OMZ-CHL tablet were 100% and more than 85% in 15 minutes, respectively, which were increased than OMZ base and OMZ-tablet. In the acute toxicological test, the value of oral $LD_{50}$(mouse) was 4.608 g/kg. OMZ-CHL was pelletized using lactose, polyethyle neglycol(PEG), D-sorbitol, Avicel PH 101, sodium laurylsulfate and polyvinylpyrrolidone(PVP) K-30, and enteric coated with HPMCP, Myvacet, acetone, ethanol and cetanol, of which dissolution rate was found to be more than 85% in 10 minutes. From the above results, it was found that OMZ-CHL is a useful means for development of new oral dosage forms of OMZ.

• Toxicological Research
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• v.16 no.3
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• pp.187-193
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• 2000

The antidotal, anticonvulsant and neuroprotective effects of physostigmine and procyclidine. the combinational prophylactics for organophosphate poisoning, were evaluated in rats. In comparison with a low protective effect (1.6 fold) of atropine (15 mg/kg) and 2-pralidoxime (30 mg/kg), the traditional antidotes regimen, a marked protection ratio of 7.3 fold was achieved by combinational pretreatment with physostigmine (0.05 mg/kg) and procyclidine (10 mg/kg), which was superior to that (3.5 fold) with pyri-dostigmine (0.1 mg/kg) and atropine (15 mg/kg). Rats exposed to a high dose (10 mg/kg. 2 X $LD_{50}$) of diisopropylfluorophosphate showed severe epileptiform seizures on electroencephalography, resulting in necrotic and apoptotic brain injuries in discrete brain regions under histopathological and TUNEL immuno-histochemical examinations in 24 hr. Such seizures and excitotoxic brain injuries were fully prevented by pretreatment with physostigmine (0.05 mg/kg) and procyclidine (10 mg/kg). in contrast to a negligible effect of pyridostigmine (0.1 mg/kg) and atropine (15 mg/kg). Taken together, it is proposed that the prophylactics composed of physostigmine and procyclidine could be a promising regimen for the prevention of lethality, seizures and brain injuries induced by organophosphate poisoning.