• Title/Summary/Keyword: lethal DO

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The Effect of Combination of Radiation with 5-Fluorouracil on Mouse Jejunal Crypt Cells (5-Fluorouracil 투여가 마우스 공장 소낭선세포의 방사선조사 효과에 미치는 영향)

  • Huh, Seung-Jae;Park, Charn-Il
    • Radiation Oncology Journal
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    • v.3 no.2
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    • pp.87-93
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    • 1985
  • The interaction of radiation and 5-Fluorouracil (5-FU) on mouse jejunal crypt cells was studied using the microcolony survival assay. 150mg/kg of 5-FU was injected intraperitoneally 15 minutes before irradiation and 6 hours after irradiation. Jejunal crypt cells of mouse survived more when 5-FU was given 15 minutes before irradiation than giving it 6 hours after irradiation. The mean lethal doses (Do) of each of irradiation alone group, 5-FU injection group of 15 minutes preceding irradiation, and 5-FU injection group of 6 hours post irradiation were, 135, 135, and 114 rad respectively. The dose effect factor (DEF) of each of 5-FU injection groups of 15 minutes preceding irradiation and of 6 hours post irradiation were 1.13 and 1.27

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Pro-Apoptotic Role of the Human YPEL5 Gene Identified by Functional Complementation of a Yeast moh1Δ Mutation

  • Lee, Ji Young;Jun, Do Youn;Park, Ju Eun;Kwon, Gi Hyun;Kim, Jong-Sik;Kim, Young Ho
    • Journal of Microbiology and Biotechnology
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    • v.27 no.3
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    • pp.633-643
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    • 2017
  • To examine the pro-apoptotic role of the human ortholog (YPEL5) of the Drosophila Yippee protein, the cell viability of Saccharomyces cerevisiae mutant strain with deleted MOH1, the yeast ortholog, was compared with that of the wild-type (WT)-MOH1 strain after exposure to different apoptogenic stimulants, including UV irradiation, methyl methanesulfonate (MMS), camptothecin (CPT), heat shock, and hyperosmotic shock. The $moh1{\Delta}$ mutant exhibited enhanced cell viability compared with the WT-MOH1 strain when treated with lethal UV irradiation, 1.8 mM MMS, $100{\mu}M$ CPT, heat shock at $50^{\circ}C$, or 1.2 M KCl. At the same time, the level of Moh1 protein was commonly up-regulated in the WT-MOH1 strain as was that of Ynk1 protein, which is known as a marker for DNA damage. Although the enhanced UV resistance of the $moh1{\Delta}$ mutant largely disappeared following transformation with the yeast MOH1 gene or one of the human YPEL1-YPEL5 genes, the transformant bearing pYES2-YPEL5 was more sensitive to lethal UV irradiation and its UV sensitivity was similar to that of the WT-MOH1 strain. Under these conditions, the UV irradiation-induced apoptotic events, such as FITC-Annexin V stainability, mitochondrial membrane potential (${\Delta}{\psi}m$) loss, and metacaspase activation, occurred to a much lesser extent in the $moh1{\Delta}$ mutant compared with the WT-MOH1 strain and the mutant strain bearing pYES2-MOH1 or pYES2-YPEL5. These results demonstrate the functional conservation between yeast Moh1 and human YPEL5, and their involvement in mitochondria-dependent apoptosis induced by DNA damage.

Antimicrobial Activity of Quercus mongolica Leaf Ethanol Extract and Organic Acids against Food-borne microorganisms (식중독균에 대한 신갈나무 잎 추출물과 유기산의 항균효과)

  • Kong, Young-Jun;Park, Boo-Kil;Oh, Deog-Hwan
    • Korean Journal of Food Science and Technology
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    • v.33 no.2
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    • pp.178-183
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    • 2001
  • This study was conducted to determine the optimal extraction condition of temperatures and kinds of extraction solvent, and antimicrobial activity of ethanol extract of Quercus mongolica leaf and organic acid against foodborne microorganisms. The antimicrobial activity of ethanol extract at $60^{\circ}C$ for 6 hour against foodborne microorganisms was stronger than those at $30^{\circ}C\;and\;90^{\circ}C$. Also, the ethanol extract showed stronger antimicrobial activity than those of water and methanol extract. The minimal inhibitory concentrations of the ethanol extract of Quercus mongolica leaf against B. cereus and L. monocytogenes, was $62.5{\sim}125\;{\mu}g/mL$ but, the minimal inhibitory concentration was $250\;{\mu}g/mL$ against S. typhimurium and P. aeruginosa and over $500\;{\mu}g/mL$ against E. coli O157:H7, respectively. The minimal inhibitory concentrations of the lactic, citric, acetic acid and the ethanol extract of Quercus mongolica leaf against B. cereus and L. monocytogenes was 2500, 5000, 1250 and $125\;{\mu}g/mL$, respectively. The combined effect of each organic acid and the ethanol extract against B. cereus was not observed but, synergistic effect was observed against L. monocytogenes. In the meantime, when the ethanol extract was combined with each organic acid at sub-lethal concentration, the combination did not increase the inhibitory effect of the most active single compound alone against E. coli O157:H7, respectively.

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Effect of Sublethal Doses of Imidacloprid on the Green Peach Aphid, Myzus persicae (Imidacloprid의 아치사량이 복숭아혹진딧물의 생물적 특성에 미치는 영향)

  • Choi, Byeong-Ryeol;Lee, Si-Woo;Song, Yoo-Han;Yoo, Jai-Ki;Chung, Bu-Keun
    • The Korean Journal of Pesticide Science
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    • v.9 no.4
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    • pp.374-379
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    • 2005
  • Sublethal dose effect of imidacloprid on green peach aphid (Myzus persicae) was investigated. Nymphs of green peach aphid newly produced were counted on 4 days after sub-lethal dose treatment of imidacloprid. Numbers of nymph were not significantly different between $LC_1$ treatment and untreated control. Their numbers of nymph were 8.8 and 12.7 at $LC_1$ and untreated control, respectively. When they were tented at $LC_{10}$, $LC_{30}$ and $LC_{50}$. their numbers of newly produced nymph were 6.0, 5.1 and 3.9 and reduction rates were 52.7%, 59.8% and 69.3% at each treatment compare to untreated control. Reduction rates of newly laid nymph were proportional to the concentrations of imidacloprid treated. Repellent effect of aphid to imidacloprid was bigger in dipping than in watering method. Secretion amount had negative correlation with imidacloprid concentration in dipping method and suppression of secretion went up to 96%. In watering method, amount of secretion did not show any difference between insecticide concentration, but suppression, compared to untreated control, was over 97%.

Susceptibility of Stink Bugs Collected in Soybean Fields in Milyang to Some Insecticides (콩 주요 노린재류의 약제감수성)

  • Bae, Soon-Do;Kim, Hyun-Joo;Lee, Geon-Hee;Park, Sung-Tae;Lee, Si-Woo
    • Korean journal of applied entomology
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    • v.47 no.4
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    • pp.413-419
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    • 2008
  • The susceptibility of five stink bugs species collected soybean fields in Milyang in 2006 to seven insecticides was evaluated using electric auto-sprayer. The insecticide deltamethirn had the lowest median lethal concentration ($LC_{50}$) of 0.4 to 2.3 ppm regardless of stink bugs species while phenthoate had the highest concentration for one-banded stink bug (Piezodorus hybneri), green stink bug (Nezara antennata), sloe bug (Dolycoris baccarum), and brown marmorated stink bug, (Halyomorpha halys); and fenthion for bean bug (Riptortus clavatus). The average $LC_{50}$ for stink bugs to seven insecticides was lowest at 7.5 ppm for R. clavatus, followed by 16.6 ppm for H. halys, 17.6 ppm for D. baccarum, 19.1 ppm for N. antennata, and 28.4 ppm for P. hybneri. The relative tolerance ratio (TR), which is the TR of 90 percent lethal concentration ($LC_{90}$) of stink bugs to the recommended concentration, was the lowest in fipronil for R. clavatus, P. hybneri and D. baccarum; fenitrothion for N. antennata; and fenthion for H. halys. The relative average TR was lowest at 0.09 for R. clavatus, followed by 0.26 for D. baccarum, 0.30 for N. antennata, 0.37 for P. hybneri, and 0.39 for H. halys. Therefore, insecticides susceptibility was highest for R. clavatus and lowest for P. hybneri while the relative average TR was lowest for R. clavatus and highest for H. halys. Accordingly, it is expected that stink bugs can be effectively controlled with by spraying insecticides in soybean field because the relative average TR value of stink bugs was below 1.0, indicating high susceptibility of stink bugs to insecticides.

A Study on Recovery from Potentially Lethal Damage Induced by $\gamma-Irradiation$ in Plateau-phase Vero Cells in vitro (평형기의 Vero세포계에서 방사선($\gamma$-선) 조사 후 발생한 잠재치사 손상의 회복에 관한 연구)

  • Kim, Il-Han;Choi, Eun-Kyung;Ha, Sung-Whan;Park, Charn-Il;Cha, Chang-Yong
    • Radiation Oncology Journal
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    • v.6 no.1
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    • pp.1-11
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    • 1988
  • Recovery from potentially lethal damage (PLDR) after irradiation was studied in plateau-phase culture of Vero cells in vitro. Unfed plateau-phase cells were irradiated with dose of 1 to 9Gy using Cs-137 irradiator. Cells then were incubated again and left in situ for 0, 1, 2, 3, 4, 5, 6, and 24 hours and then were trypsinized explanted, and subcultured in fresh RPMI-1640 media containing $0.33\%$ agar. Cell survival was measured by colony forming ability. An adequate number of heavily irradiated Vero cells were added as feeder cells to make the total cell number constant in every culture dish. As the postirradiation in situ incubation time increased, surviving fraction increased by PLDR. The rate of PLDR was so rapid that increased surviving fraction reached saturation level at 2 to 4 hours after in situ incubation. As the radiation dose increased, the rate of PLDR fastened and the magnitude of increased surviving fraction at saturation level by PLOR also increased. In analysis of cell survival curve fitted to the linear-quadratic model, the linear inactivation coefficient $(\alpha)$ decreased largely and reached nearly to zero but the quadratic inactivation coefficient $(\beta)$ increased minimally by increment of postirradiation in situ incubation time. So PLDR mainly affected the damage expressed as $\alpha$, In the multitarget model, significant change was not obtained in $D_0\;but\;in D_q$. Therefore, shoulder region in cell survival curve was mainly affected by PLDR and terminal slope was not influenced at all. And dose-modifying factor by PLDR was relatively higher in shoulder region, that is, in low dose area below 3 Gy.

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Application of Apoptogenic Pretreatment to Enhance Anti-tumor Immunity of Granulocyte-Macrophage Colony Stimulating Factor (GM-CSF)-secreting CT26 Tumor Cells

  • Jun, Do-Youn;Jaffee, Elizabeth M;Kim, Young-Ho
    • IMMUNE NETWORK
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    • v.5 no.2
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    • pp.110-116
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    • 2005
  • Background: As an attempt to develop a strategy to improve the protective immune response to GM-CSF-secreting CT26 (GM-CSF/CT26) tumor vaccine, we have investigated whether the apoptogenic treatment of GM-CSF/CT26 prior to vaccination enhances the induction of anti-tumor immune response in mouse model. Methods: A carcinogeninduced mouse colorectal tumor, CT26 was transfected with GM-CSF gene using a retroviral vector to generate GM-CSF-secreting CT26 (CT26/GM-CSF). The CT26/GM-CSF was treated with ${\gamma}$-irradiation or mitomycin C to induce apoptosis and vaccinated into BALB/c mice. After 7 days, the mice were injected with a lethal dose of challenge live CT26 cells to examine the protective effect of tumor vaccination in vivo. Results: Although both apoptotic and necrotic CT26/GM-CSF vaccines were able to enhance anti-tumor immune response, apoptotic CT26/GM-CSF induced by pretreatment with ${\gamma}$-irradiation (50,000 rads) was the most potent in generating the anti-tumor immunity, and thus 100% of mice vaccinated with the apoptotic cells remained tumor free for more than 60 days after tumor challenge. Conclusion: Apoptogenic pretreatment of GM-CSF-secreting CT26 tumor vaccine by ${\gamma}$-irradiation (50,000 rads) resulted in a significant enhancement in inducing the protective anti-tumor immunity. A rapid induction of apoptosis of CT26/GM-CSF tumor vaccine at the vaccine site might be critical for the enhancement in anti-tumor immune response to tumor vaccine.

Squamous cell carcinoma of the maxillary sinus mimicking periodontitis

  • Na, Ji Yeon;Kang, Joo Hyun;Choi, Seong-Ho;Jeong, Ho-Gul;Han, Sang-Sun
    • The Journal of the Korean dental association
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    • v.55 no.4
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    • pp.276-283
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    • 2017
  • Maxillary sinus squamous cell carcinoma is a relatively rare disease, comprising only 3% of malignant diseases of head and neck. As the growth rate is high and its prognosis is poor compared to others, the 5-year survival rate of maxillary sinus squamous cell carcinoma(MSSCC) is 23.4-49%. We introduce two rare clinical cases of squamous cell carcinoma originated from maxillary sinus of which symptoms include toothache and gingival swelling. On clinical examinations of both patients, deep periodontal pockets on upper right posterior teeth were detected. On panoramic images, the bony destruction of the maxillary sinus and its surrounding structures were not obvious and only alveolar bone loss was noted. It is difficult to diagnose MSSCC at an early stage due to symptoms of tooth pain and gingival swelling that are similar to that of periodontal diseases. However, if the symptoms do not improve after routine treatment of upper teeth, dentists should bear in mind of underlying malignant mass as differential diagnosis, thus early detection of the lethal disease. The aim of this study is to caution dental practitioners that malignancies have a potential to mimic periodontal diseases by introducing two cases of maxillary sinus squamous cell carcinoma presented as periodontitis.

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Tolerance and Histological Responses to Formalin of Black Seabream Acanthopagrus schlegelii Juveniles (감성돔(Acanthopagrus schlegelii) 치어의 포르말린에 대한 내성 및 조직학적 반응)

  • Myeong, Jeong-In;Min, Byung Hwa;Park, Mi Seon;Hwang, Hyung Kyu;Do, Jeung-Wan;Jeoung, Kyung Il;Chang, Young Jin;Jeong, Dal Sang
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.46 no.6
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    • pp.923-929
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    • 2013
  • Black seabream juveniles Acanthopagrus schlegelii held at $20^{\circ}C$ were exposed to formalin at concentrations of 50 to 400 ppm, and tolerance values were determined by calculating median lethal concentration values (LC50) through probit analysis. The 12-, 24, 48, 72- and 96-h LC50 values for formalin were 297, 233, 171, 162 and 157 ppm, respectively. The histological effects of formalin on gill and liver tissues in this fish were determined. No histological effects were observed in the control group. The intensity of cell damage increased with the concentration of, and duration of exposure to, formalin. Hyperplasia, separation and epithelial necrosis, epithelial lifting, lamellar synechiae and collapsed lamellae were observed in gill tissues exposed to formalin. Hepatic lesions in liver tissues of fishes exposed to formalin were characterized by cloudy swelling of hepatocytes, necrosis, cytoplasmic vacuolization, deposition of pigments, spongiosis hepatis, nuclear hypertrophy, dilation of sinusoids and bile stagnation. The LC50 values and histological results obtained in this study will aid in designing treatment regimens to minimize toxic side effects and increase efficacy.

Increased Immunogenicity and Protective Efficacy of a P. aeruginosa Vaccine in Mice Using an Alum and De-O-Acylated Lipooligosaccharide Adjuvant System

  • Ryu, Ji In;Wui, Seo Ri;Ko, Ara;Do, Hien Thi Thu;Lee, Yeon Jeong;Kim, Hark Jun;Rhee, Inmoo;Park, Shin Ae;Kim, Kwang Sung;Cho, Yang Je;Lee, Na Gyong
    • Journal of Microbiology and Biotechnology
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    • v.27 no.8
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    • pp.1539-1548
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    • 2017
  • Pseudomonas aeruginosa (P. aeruginosa) is an opportunistic pathogen that commonly causes fatal infections in cystic fibrosis and burn patients as well as in patients who are hospitalized or have impaired immune systems. P. aeruginosa infections are difficult to treat owing to the high resistance of the pathogen to conventional antibiotics. Despite several efforts, no effective prophylactic vaccines against P. aeruginosa are currently available. In this study, we investigated the activity of the CIA06 adjuvant system, which is composed of alum and de-O-acylated lipooligosaccharide, on a P. aeruginosa outer membrane protein (OMP) antigen vaccine in mice. The results indicated that CIA06 significantly increased the antigen-specific IgG titers and opsonophagocytic activity of immune sera against P. aeruginosa. In addition, the antibodies induced by the CIA06-adjuvanted vaccine exhibited higher cross-reactivity with heterologous P. aeruginosa strains. Finally, mice immunized with the CIA06-adjuvanted vaccine were effectively protected from lethal P. aeruginosa challenge. Based on these data, we suggest that the CIA06 adjuvant system might be used to promote the immunogenicity and protective efficacy of the P. aeruginosa OMP vaccine.