• Title/Summary/Keyword: Lethal time

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Acute Toxicity of Nitrite on Juvenile Banded Catfish(Pseudobagurus fulvidraco) (동자개 치어의 아질산 급성 독성)

  • Sohn, Sang-Gyu;Lee, Young-Sik;Kim, Kwang-Seog;Lee, Han-Na;Lee, Joo-Yong;Back, Sun-Jung
    • Journal of Fisheries and Marine Sciences Education
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    • v.27 no.1
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    • pp.41-48
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    • 2015
  • Juvenile banded catfish(Pseudobagurus fulvidraco, mean length $10.4{\pm}0.37cm$ and mean weight $14.5{\pm}0.46g$) were exposed to several nitrite(${NO_2}^-$) concentrations for 96h at pH levels of $6.18{\pm}0.54$, $6.5{\pm}0.30$ and $7.07{\pm}0.22$. The result showed that cumulative mortalities of fish to ${NO_2}^-$ levels of 12.4, 19.8, 33.9 and 53.6 mg/L at pH levels of $6.18{\pm}0.54$ were 20, 25, 40 and 85%, respectively. At pH $6.5{\pm}0.54$, mortalities to ${NO_2}^-$ 22.4, 36.4, 45.3 and 63.2 mg/L were 25, 35, 50 and 100%, respectively. At pH $7.07{\pm}0.22$, mortalities to ${NO_2}^-$ 25.5, 45.7, 56.3 and 66.4 mg/L were 0, 55, 70 and 100%, respectively. The 96h-$LC_{50}$(median lethal concentration, $LC_{50}$) of fish to several ${NO_2}^-$ concentrations at pH levels of $6.18{\pm}0.54$, $6.5{\pm}0.30$ and $7.07{\pm}0.22$ were assessed in these experiments. 96h-$LC_{50}$ at pH levels of $6.18{\pm}0.54$, $6.5{\pm}0.30$ and $7.07{\pm}0.22$ were 32.68, 40.49 and 45.85 mg/L, respectively. It indicated that acute toxicity of ${NO_2}^-$ to juvenile banded catfish increased with low levels of pH and lengthening of exposure time to ${NO_2}^-$. In particular, smaller fish(mean weight $14.5{\pm}0.46g$) were more sensitive to ${NO_2}^-$ than larger fish(mean weight $81.7{\pm}1.42g$; not published). The 96h-$LC_{50}$ of juvenile banded catfish to ${NO_2}^-$ would be primary guideline for water quality management in the intensive culture system such as RAS and BFT.

Study on Single-dose Intramuscular Toxicity of Shinbaro Pharmacopuncture in Sprague-Dawley (SD) Rats and Beagle Dogs (신바로 약침의 SD 랫드와 비글견에 대한 단회 근육투여 독성시험)

  • Lee, Jin-Ho;Chung, Hwa-Jin;Lee, In-Hee;Lee, Jae-Woong;Kim, Eun-Jee;Kim, Min-Jeong
    • Journal of Korean Medicine Rehabilitation
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    • v.25 no.3
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    • pp.1-9
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    • 2015
  • Objectives To evaluate Shinbaro Pharmacopuncture safety through analysis of potential single-dose intramuscular toxicity of Sinbaro Pharmacopucture in SD rats and Beagle dogs. Methods Single-dose intramuscular toxicity of Shinbaro Pharmacopuncture was assessed in accordance with Korea Food and Drug Administration Guidelines for toxicity testing of Medicinal Products. The SD rats were treated intramuscularly with Shinbaro Pharmacopuncture at doses of 0, 4.6, 9.2, and 18.5 mg/kg, respectively. The Beagle dogs were treated intramuscularly with Shinbaro Pharmacopuncture at doses of 2.3, and 4.6 mg/kg, respectively, and after 3 days, the procedure was repeated a second time at doses of 0.6, and 1.2 mg/kg, respectively, for toxicity testing. Mortality, change in body weight, and necropsy findings were examined for the study period. Results There were no mortalities, general symptoms, or body weight changes in the SD rats. While pyelectasis of the left kidney was observed in a male rat in the 4.6 mg/kg administration group, natural occurrence is common, and does not appear to be related with the test substance. No mortalities were observed in the Beagle dogs. In assessment of general symptoms, a female dog in the 9.2 mg/kg group displayed body weight decrease due to leftover food, but the change in body weight was within the normal range seen at 6~7 months, and the necropsy findings were not significant. The toxicity of the test substance appears to be minimal. Conclusions The results suggest that the lethal dose 50 ($LD_{50}$) and approximate lethaldose (ALD) value in single intramuscular administration of Shinbaro Pharmacopuncture in SD rats and Beagle dogs are higher than 18.5 mg/kg.

Effective Heat Treatment Techniques for Control of Mung Bean Sprout Rot, Incorporable into Commercial Mass Production

  • Lee, Jung-Han;Han, Ki-Soo;Kim, Tae-Hyoung;Bae, Dong-Won;Kim, Dong-Kil;Kang, Jin-Ho;Kim, Hee-Kyu
    • The Plant Pathology Journal
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    • v.23 no.3
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    • pp.174-179
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    • 2007
  • Seedlot disinfection techniques to control mung bean sprout rot caused by Colletoricum acutatum and C. gloeosporioides were evaluated for commercial production scheme. Soaking seedlots in propolis (100 X) and ethanol (20% for 30 min) appeared promising with control values of 85.5 and 80.8 respectively, but still resulted in up to 20% rot incidence. None of the C. acutatum conidia survived through hot water immersion treatment (HWT) for 10 min at temperatures of 55, 60 and $65^{\circ}C$, whereas the effective range of the dry heat treatment (DHT) was $60-65^{\circ}C$. Tolerance of mung bean seedlot, as estimated by hypocotyl elongation and root growth, was lower for HWT than for DHT. Germination and growth of sprouts were excellent over the range of $55-65^{\circ}C\;at\;5^{\circ}C$ intervals, except for HWT at $65^{\circ}C$ for 5 min. At this marginal condition, heat damage appeared so that approximately 2% of seeds failed to sprout to normal germling and retarded sprouts were less than 5% with coarse wrinkled hypocotyls. These results suggested that DHT would be more feasible to disinfect mung bean seedlots for commercial sprout production. Heat treatment at above ranges was highly effective in eliminating the epiphytic bacterial strains associated with marketed sprout rot samples. HWT of seedlot at 55 and $60^{\circ}C$ for 5 min resulted in successful control of mung bean sprout rot incidence with marketable sprout quality. DHT at 60 and $65^{\circ}C$ for 30 min also gave good results through the small-scale sprouting system. Therefore, we optimized DHT scheme at 60 and $65^{\circ}C$ for 30 min, considering the practical value of seedlot disinfection with high precision and accuracy. This was further proved to be a feasible and reliable method against anthracnose incidence and those bacterial strains associated with marketed sprout rot samples as well, through factory scale mung bean sprout production system.

Retinoid Receptors in Gastric Cancer: Expression and Influence on Prognosis

  • Hu, Kong-Wang;Chen, Fei-Hu;Ge, Jin-Fang;Cao, Li-Yu;Li, Hao
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.5
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    • pp.1809-1817
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    • 2012
  • Background: Gastric cancer is frequently lethal despite aggressive multimodal therapies, and new treatment approaches are therefore needed. Retinoids are potential candidate drugs: they prevent cell differentiation, proliferation and malignant transformation in gastric cancer cell lines. They interact with nuclear retinoid receptors (the retinoic acid receptors [RARs] and retinoid X receptors [RXRs]), which function as transcription factors, each with three subclasses, ${\alpha}$, ${\beta}$ and ${\gamma}$. At present, little is known about retinoid expression and influence on prognosis in gastric cancers. Patients and Methods: We retrospectively analyzed the expression of the subtypes RARa, $RAR{\beta}$, $RAR{\gamma}$, RXRa, $RXR{\beta}$, $RXR{\gamma}$ by immunohistochemistry in 147 gastric cancers and 51 normal gastric epithelium tissues for whom clinical follow-up data were available and correlated the results with clinical characteristics. In addition, we quantified the expression of retinoid receptor mRNA using real-time PCR (RT-PCR) in another 6 gastric adenocarcinoma and 3 normal gastric tissues. From 2008 to 2010, 80 patients with gastric cancers were enrolled onto therapy with all-trans-retinoic acid (ATRA). Results: RARa, $RAR{\beta}$, $RAR{\gamma}$ and $RXR{\gamma}$ positively correlated with each other (p < 0.001) and demonstrated significantly lower levels in the carcinoma tissue sections (p < 0.01), with lower $RAR{\beta}$, $RAR{\gamma}$ and RXRa expression significantly related to advanced stages (p < =0.01). Tumors with poor histopathologic grade had lower levels of RARa and $RAR{\beta}$ in different histological types of gastric carcinoma (p < 0.01). Patients whose tumors exhibited low levels of RARa expression had significantly lower overall survival compared with patients who had higher expression levels of this receptor (p < 0.001, HR=0.42, 95.0% CI 0.24-0.73), and patients undergoing ATRA treatment had significantly longer median survival times (p = 0.007, HR=0.41, 95.0% CI 0.21-0.80). Conclusions: Retinoic acid receptors are frequently expressed in epithelial gastric cancer with a decreased tendency of expression and RARa may be an indicator of a positive prognosis. This study provides a molecular basis for the therapeutic use of retinoids against gastric cancer.

Ecotoxicological Characteristics of Gammarus sobaegensis Ueno by Acute and Chronic pH Depression on Artificial Static Waters (pH 저하가 소백옆새우(Gammarus sobaegensis Ueno)에 미치는 급, 만성 생태독성학적 특성 -1. 정체성 조건-)

  • Park, Jung-Ho;Cho, Dong-Hyun;Jung, Geun
    • Korean Journal of Environmental Biology
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    • v.18 no.4
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    • pp.377-385
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    • 2000
  • This study was carried out to investigate the ecotoxicological response on Gammarus sobaegensis Ueno with acid stress. Mean value of $LT_{50}$ (lethal time 50%) under pH 3 condition as acute ecotoxicity test was observed to be 0.271 ($\pm$0.146) day. And 0.812 ($\pm$0.377) day under pH 4, respectively. Mean value of $LT_{50}$ under pH 3 and 5 were 6.313 ($\pm$0.828), and 9.475 ($\pm$4.881) day, respectively. Variance in chronic ecotoxicity test pH (F ratio: 11.240, P< 0.0005) and times (F ratio: 2.916, P< 0.0005) as single factor were revealed to be the major factor for determining LT$_{50}$ with acid depression. The variation of secondary gill surface with acid stress to be certain that wrinkle phenomenon. Being weak tolerance of G. sobaegensis against the acid stress, it shows the possibility to be examined as an aquatic toxicity test organism.

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Control of Fusarium Wilt of the Strawberry Caused by Fusarium oxysporum f. sp. fragariae of Solarization with Compost and Calcium Cyanamide Application (태양열 소독시 유기물과 석회질소 병행 처리에 의한 딸기 시들음병균 방제)

  • Nam, Myeong-Hyeon;Kim, Hyeon-Suk;Kim, Hong-Gi
    • Research in Plant Disease
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    • v.17 no.1
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    • pp.32-37
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    • 2011
  • Field experiments were conducted to evaluate the effectiveness of soil solarization at the Nonsan Strawberry Experiment Station, Korea in 2006 and 2008. In in vitro tests, exposure times to achieve an $LD_{100}$ of Fusarium oxysporum f. sp. fragariae were 6.6 days and 5.1 days at $45^{\circ}C$ and $50^{\circ}C$, respectively. A 100% lethal temperature was $46.7{\pm}0.1^{\circ}C$ for the same fungus. For field trials, solarization was conducted during the summer season using polyethylene mulch in a plastic house. The organic matter+calcium cyanamide+solarization treatment increased pH, organic matter, and calcium content compared to those before treatment in soil analysis, but no effect had an urea+solarization treatment. The temperatures at 10 cm depth were different in each treatment and the highest temperature was recorded from July 30 to August 10. The average temperature in organic matter+calcium cyanamide+solarization treatment at 10 cm depth was $3{\sim}4^{\circ}C$ higher than that in all the other treatments. All solarization treatments reduced the soil population of F. oxysporum f. sp. fragariae at 100% in 2008 relative to the non-treated control. All solarization treatments reduced Fusarium wilt incidence to 0% in 2006 and 2008. The effect of organic matter+calcium cyanamide+solarization against F. oxysporum f. sp. fragariae indicates that there may be future alternatives to traditional solarization for disease control as well as reducing the time needed.

Survival and Physiological Response of Olive Flounder, Paralichthys olivaceus Exposed to Seawater Chlorinated by Chlorine Dioxide ($CIO_2$) (이산화염소($CIO_2$) 처리해수에 노출된 넙치, Paralichthys olivaceus의 생존과 생리적 반응)

  • 김흥윤;김진도
    • Journal of Aquaculture
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    • v.16 no.3
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    • pp.151-158
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    • 2003
  • This study was conducted to estimate the effects of residual chlorine dioxide ($CIO_2$) in chlorinated seawater on survival and physiological responses (hematocrit: Ht, hemoglobin: Hb, serum electrolyte and glucose levels, and osmolality) of olive flounder, Paralichthys olivaceus. All the flounders were exposed for 10 min to different concentrations of residual $CIO_2$ just after chlorination for 1 min in each experimental aquarium (EA). ClO$_2$-free seawater was continuously supplied to each EA after 10 min exposure to $CIO_2$. By means of probit analysis, the median lethal times (LT$_{50}$, min) of flounder exposed to 0.43 and 0.51 ppm $CIO_2$, were at 103 and 32 min, respectively. In the range from 0.34 to 0.51 ppm $CIO_2$, the values of Ht, Hb, electrolytes and osmolality of fish exposed to $CIO_2$ were significantly elevated as elapsed time and residual concentrations of $CIO_2$ increased after chlorination. The levels of Ht, Hb, electrolytes and osmolality in flounder exposed to 0.27 ppm $CIO_2$ were not significantly different compared to control fish, which were maintained in $CIO_2$-free seawater; however, the levels of serum glucose were significantly increased with elapse times.

Cardiac Toxicity Following a Diphenhydramine Overdose (디펜히드라민 중독환자의 심독성에 관한 연구)

  • Park, Sung-Jun;Park, Jong-Hak;Um, In-Kyung;Park, Kyung-Ae;Kim, Do-Hyoun;Kim, Su-Jin;Lee, Sung-Woo;Hong, Yun-Sik
    • Journal of The Korean Society of Clinical Toxicology
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    • v.9 no.1
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    • pp.20-25
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    • 2011
  • Purpose: This study was designed to analyze the contributing factors, as well as the incidence and nature of the cardiac toxicity, in patients presenting with diphenhydramine overdose. Methods: We retrospectively reviewed the medical records of the intoxicated patients who presented to the ED of Korea University Anam Hospital from January 2008 to December 2010. Those patients who visited due to a diphenhydramine overdose were selected and the following features were recorded for analysis: the general characteristics, vital signs, the amount of ingested diphenhydramine, the time interval from ingestion to presentation, the coingested drugs (if any), the toxicities and the ECG findings. Cardiac toxicity, while defined mainly in terms of the temporary ECG changes such as QTc prolongation, right axis deviation, QRS widening, high degree AV block and ischemic changes, also encompassed cardiogenic shock, which is a clinical finding. Results: A total of eighteen patients were enrolled. Of the eighteen patients, eight had ingested diphenhydramine only, while ten had ingested other drugs in addition to diphenhydramine. The most commonly observed toxicity following diphenhydramine overdose included cardiac toxicity (78%). Cardiac toxicity was observed in all the patients who presented to the emergency department 2 hours after ingestion. The patients with QTc prolongation turned out to have ingested significantly larger amounts of diphenhydramine. Conclusion: QTc prolongation and right axis deviation were common findings for the patients with a diphenhydramine overdose. QTc prolongation was more likely to occur with ingesting larger amounts of diphenhydramine. Close monitoring is mandatory for patients who have ingested large amounts of diphenhydramine to prevent such potentially lethal cardiac toxicity.

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Treatment outcomes of radiotherapy for anaplastic thyroid cancer

  • Park, Jong Won;Choi, Seo Hee;Yoon, Hong In;Lee, Jeongshim;Kim, Tae Hyung;Kim, Jun Won;Lee, Ik Jae
    • Radiation Oncology Journal
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    • v.36 no.2
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    • pp.103-113
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    • 2018
  • Purpose: Anaplastic thyroid cancer (ATC) is a rare tumor with a lethal clinical course despite aggressive multimodal therapy. Intensity-modulated radiotherapy (IMRT) may achieve a good therapeutic outcome in ATC patients, and the role of IMRT should be assessed. We retrospectively reviewed outcomes for ATC treated with three-dimensional conformal radiotherapy (3D-CRT) or IMRT to determine the optimal treatment option and explore the role of radiotherapy (RT). Materials and Methods: Between December 2000 and December 2015, 41 patients with pathologically proven ATC received RT with a sufficient dose of ${\geq}40Gy$. Among them, 21 patients (51%) underwent surgery before RT. Twenty-eight patients received IMRT, and 13 received 3D-CRT. Overall survival (OS) and progression-free survival (PFS), patterns of failure, and toxicity were examined. Results: The median follow-up time for survivors was 38.0 months. The median and 1-year OS and PFS rates were 7.2 months and 29%, 4.5 months and 15%, respectively. Surgery significantly improved the prognosis (median OS: 10.7 vs. 3.9 months, p = 0.001; median PFS: 5.9 vs. 2.5 months, p = 0.007). IMRT showed significantly better PFS and OS than 3D-CRT, even in multivariate analysis (OS: hazard ratio [HR] = 0.30, p = 0.005; PFS: HR = 0.33, p = 0.005). Significantly higher radiation dose could be delivered with IMRT than 3D-CRT ($EQD2_{10}$ 66 vs. 60 Gy, p = 0.005). Only 2 patients had grade III dermatitis after IMRT. No other severe toxicity ${\geq}grade$ III occurred. Conclusion: Patients with ATC showed better prognosis through multimodal treatment. Furthermore, IMRT could achieve favorable survival rates by safely delivering higher dose than 3D-CRT.

Effects of Silt and Clay on the Rates of Respiration, Filtration and Nitrogen Excretion in Shellfish, Mactra veneriformis (동죽의 호흡률, 여수율 및 질소배설에 미치는 부니의 영향)

  • LEE Jeong-Yeol
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.27 no.1
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    • pp.59-68
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    • 1994
  • The effects of silt and clay, water temperature and salinity on the metabolic activities: rates of respiration, filtration and nitrogen excretion in the clam, Mactra veneriformis, were investigated in ranges of $0{\sim}250ppm,\;15{\sim}25^{\circ}C\;and\;10{\sim}30\%0$ respectively. The weight specific respiration rate decreased with shell length and significantly declined at lower temperatures and lower salinity levels. Average respiration rates, filtration rates and ammonia excretion rates of the clam groups declined as water temperature was lowered. The respiration rate(R) and the filtration rate(F) decreased as the concentration of silt and clay(C) increased, the relationships between the two parameters were expressed as a regression line, R=a+b LogC and LogF=a+b LogC, respectively. On the rearing experiment treated with 50ppm of silt and clay, the relationship between the accumulative mortality(M) and the elapsed day(T) was $M=0.0186T^{2.7965}$, and the median lethal time was calculated at 16.8 days. From the rearing experiment, both rate of respiration and ammonia nitrogen excretion of experimental groups and control groups decreased with elapsed days, the rates of experimental groups, especially declined more compared with those of the control groups.

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