• Title/Summary/Keyword: Lethal rate

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The Tendency of Scientific Research of Tree Improvement and Forest Management in Japan (일본(日本)의 임목육종(林木育種) 및 삼림경영연구동향(森林經營硏究動向))

  • Kim, Young Ho;Son, Doo Sik
    • Current Research on Agriculture and Life Sciences
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    • v.2
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    • pp.42-55
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    • 1984
  • The direction of scientific researches on tree improvement and forest management in several universities and research institutes in Japan can be summarized as follows: They put a great emphasis on sugi, Cryptomeria japonica and cypress, Chamaecyparus oblusa which are two major conifer species largerly planted in the Japanese forestry. In the research of sugi, a great concern has been made in evaluating inheritance of forest tree, quantitative characters and genetic parameter of growth, and in breeding for resistance to diseases and insects and to all the natural calamities. Interaction between environmental conditions and genetic nature of tree can be concerned factors in relation with forest damage, together with silvicultural conditions and pest infestation. Selfing hybrids of $F_1$ made from crossing twisted-leaf sugi, defomity leaf type and midori sugi, normal leaf type segregated the normal needle, twisted needle, green leaf and albino leaf type. It seemed that separation of many defomity individuals can be governed by two dominant complementary genes and from the near loci of which it was detected lethal genes. 52% of Japanese forestry is occupied by the small forest landowners like Korean forestry. This made difficulty for forest improvement such as progressive afforestation and for capital accumulation form forestry. The Forest Corporation was established at first in 1959 to aming at productive forestry structure and forest management, and afforestation. For these purpose, 35 Forest Corporations are at moment operating throughout Japan. However, investment in forestry business becomes less attractive since the wage in forest production duction increased in higher trend. than timber price. Therefore, an artifical afforestation becomes yearly decreased. At present. the self-sufficient rate of timber production in Japan is about 35%, and so a great effort is being made to increase self-sufficient rate of timber production.

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The Experimental Study on Anti-thrombotic and Anti-inflammatory Effect of NeungaSoJeokTang(NSJT) (능아소적탕(稜莪消積湯)의 항혈전(抗血栓) 및 항염작용(抗炎作用)에 대한 실험적(實驗的) 연구(硏究))

  • Je, Jong-Min;Yoo, Dong-Youl
    • The Journal of Korean Obstetrics and Gynecology
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    • v.20 no.3
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    • pp.45-64
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    • 2007
  • Purpose: This study was performed to evaluate anti-thrombotic and anti-inflammatory effects of NeungaSoJeokTang water extract (NSJT). Methods: In the study of anti-inflammatory effects, NSJT was investigated using cultured cells and murine models. As for the parameters of inflammation, levels of several inflammatory cytokines and chemical mediators which are known to be related to inflammation were determined in mouse lung fibroblast cells(mLFC) and RAW 264.7 cells. Results: Prior to the experiment, we evaluated sGOT, sGPT, BUN and creatine after the treatment. As a result, NSJT was innoxious on liver and kidney. In experiment of anti-thrombotic effect, NSJT inhibited the platelet aggregation induced by ADP and epinephrine, and inhibited pulmonary embolism induced by collagen and epinephrine. NSJT did not affect significantly the blood flow rate both in vitro and in vivo. NSJT increased platelet number and fibrinogen amount, and NSJT shortened PT and APTT in thrombus model induced by dextran. In experiment of anti-inflammatory effect, NSJT inhibited $IL-1{\beta}$, IL-6, $TNF-{\alpha}$, COX-2 and NOS-II mRNA expression in a concentration-dependent manner in RAW 264.7 cell line, and inhibited significantly NO production at 50, 100 ${\mu}g/ml$, and also inhibited ROS production in a concentration-dependent manner. NSJT inhibited $IL-1{\beta}$, IL-6 and $TNF-{\alpha}$ production significantly in serum of acute inflammation-induced Balb/c mice, and decreased $IL-1{\beta}$, IL-6 and $TNF-{\alpha}$ production in spleen tissue, but increased $IL-1{\beta}$, IL-6 and $TNF-{\alpha}$ production in liver tissue. NSJT increased survival rate at the 3th day in ICR mice with lethal endotoxemia induced by LPS. Conclusion: These results suggest that NSJT can be used for treating diverse female diseases caused by thrombosis and inflammation such as pelvic pain, pelvic inflammatory disease as well as vulvar pain due to vulvitis, vulvar vestibulitis and so on.

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Protective efficacy of a novel multivalent vaccine in the prevention of diarrhea induced by enterotoxigenic Escherichia coli in a murine model

  • Zhao, Hong;Xu, Yongping;Li, Gen;Liu, Xin;Li, Xiaoyu;Wang, Lili
    • Journal of Veterinary Science
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    • v.23 no.1
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    • pp.7.1-7.14
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    • 2022
  • Background: Enterotoxigenic Escherichia coli (ETEC) infection is a primary cause of livestock diarrhea. Therefore, effective vaccines are needed to reduce the incidence of ETEC infection. Objectives: Our study aimed to develop a multivalent ETEC vaccine targeting major virulence factors of ETEC, including enterotoxins and fimbriae. Methods: SLS (STa-LTB-STb) recombinant enterotoxin and fimbriae proteins (F4, F5, F6, F18, and F41) were prepared to develop a multivalent vaccine. A total of 65 mice were immunized subcutaneously by vaccines and phosphate-buffered saline (PBS). The levels of specific immunoglobulin G (IgG) and pro-inflammatory cytokines were determined at 0, 7, 14 and 21 days post-vaccination (dpv). A challenge test with a lethal dose of ETEC was performed, and the survival rate of the mice in each group was recorded. Feces and intestine washes were collected to measure the concentrations of secretory immunoglobulin A (sIgA). Results: Anti-SLS and anti-fimbriae-specific IgG in serums of antigen-vaccinated mice were significantly higher than those of the control group. Immunization with the SLS enterotoxin and multivalent vaccine increased interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) concentrations. Compared to diarrheal symptoms and 100% death of mice in the control group, mice inoculated with the multivalent vaccine showed an 80% survival rate without any symptom of diarrhea, while SLS and fimbriae vaccinated groups showed 60 and 70% survival rates, respectively. Conclusions: Both SLS and fimbriae proteins can serve as vaccine antigens, and the combination of these two antigens can elicit stronger immune responses. The results suggest that the multivalent vaccine can be successfully used for preventing ETEC in important livestock.

Effects of Ammonia Exposure on Survival Rate and Hematological Characteristics Changes in Juveniles of Sevenband Grouper, Epinephelus septemfasciatus (능성어 (Epinephelus septemfasciatus) 치어의 생존율과 혈액학적 특성 변화에 미치는 암모니아 노출의 영향)

  • Kim, Jung Hyun;Park, Jong Youn;Lee, Jeong Yong;Lee, Jin Hwan;Hwang, Hyung Kyu;Cho, Jae Kwon
    • Korean Journal of Ichthyology
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    • v.29 no.1
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    • pp.13-21
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    • 2017
  • We investigated that changes of survival rate and hematological factors in sevenband grouper (Epinephelus septemfasciatus), exposed to ammonia. First, the fish was exposed and was observed survival rate. We observed the survival rate of the fish when exposed at each ammonia concentrations (0, 0.35, 0.4, 0.5, 0.8 mg/L, $NH_3$) for 96 hours. The 96-h $LC_{50}$ (lethal ambient concentration for 50% of the population) of $NH_4^+$ and un-ionized ammonia ($NH_3$) for sevenband grouper were 26.7 and 0.6 mg/L, respectively. Secondly, we exposed the fish to 96-h $LC_{50}$ ammonia concentration (0.6 mg/L) for 96 hours, then sampled the blood of groupers for analysis of cortisol, glucose, $NH_3$, GOT, GPT, total protein (TP), electrolytes ($Na^+$, $Cl^-$) and osmolality in plasma. The plasma cortisol, glucose, GOT and GPT were increased with increasing of elapsed time and ammonia concentration. In addition, the $NH_3$ and total protein in plasma were significantly increased to 12 hours exposed to ammonia, and then decreased. But, the values were significantly higher than the control. The plasma electrolytes ($Na^+$, $Cl^-$) and osmolality were decreased with increasing of elasped time. The results in the present study suggest that the continuous exposure of ammonia to juveniles of sevenband grouper may be a stressor and negative influence.

Studies on the Cellular Metabolism in Microorganisms as Influenced by Gamma-irradiation.(II) - On the Respiration Rate and Dehydrogenase Actibity in Yeast Cells Irradiated by $\gamma$-ray. (미생물의 세포생리에 미치는 전이방사선의 영향에 관한 연구 (제 2보) - 효모균의 산소호흡기및 탈수소효소능에 대한 $\gamma$-ray 의 영향)

  • 김종협
    • Korean Journal of Microbiology
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    • v.5 no.2
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    • pp.69-78
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    • 1967
  • Kim, Jong Hyup, (Div. of Biology, Atomic Energy Research Institute.) Studies on the Cellular Metabolism in Microorganisms as influenced by Gamma-irradiation(II). On respiration rate and dehydrogenase activity of yeast cells irradiated by gamma ray from cobalt-60. 1. Oxygen uptake rate of the gamma irraiated yeast cells had been measured with Warburg's manometer, and the $O_{2}$-uptake was compared with those of normal cells. The rate of endogetious respiration increases in its $O_2$-uptake at 150, 000 rentgen dose, and at higher rentoen doses it was decreased. Exogenous respiration begin to decrease in its O_2$-uptake at 5, 000r. doses of irradiation, further decrease with increasing of doses unproportionally. 2. It appears that plasma-membrane and nuclear membrane of yeast cells have changed and denatured by gamma-irradiation, as exogenous respiration of glucose had been decreased at a dose of 200, 000r's irradiation. 3. The activity of glucose, alcoholic, lactic, succinic and glutamic deliydrogenase (G.D.H., A.D.H., L.D.H., S.D.11., and GL.D.H.) in the gamma irradaited cells had been assayed by T.T.C.(Triphenyl tetrazolium chloride) method and spectrophotometry, the obtained results were compared with those of normal cells. 4. At a dose of and 10, 000 rentgens' irradiation of gamma ray, the activty of each debydrogenase (G.D.H., A.D.H., L.D.H., ) shows a sharp and highest peak in optical absorbalicy, but each abtivity of S.D.H and Gl.D.H shows its' maximum peak at a dose of 30, 000r. 5. The curve of each dehydrogenase activity was found to be rhythmical according to dose-rate of gamma irradiation. 6. Comparing with activity of debydrogenase each other, the maximum peak in optical absorbency can be arranged according to order as follows; glucose > alcoholoic > lactic > glutamic > succinic, this order is identical to the order of breakdown utility in respiration of normal yeast cells. 7. The activity of dehydrogenase experimented exhibit a resistance against gamma irradiation at lethal dose of cells, and the activity of dehydrogenase are found to be much resistant than those of respiratory system. We may assume that the membrane substrate of mitochondria or cytoplasm had been destructed by gamma-irradiation much more than that of dehydronase system.

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Gamma Radiation Sensitivity and Quantitative Characters in M1 Generation of Heteropappus hispidus (Thunb.) (갯쑥부쟁이(Heteropappus hispidus (Thunb.))의 감마방사선 감수성과 M1 세대 형질변동 특징)

  • Oh, Byung-Kwon;Hong, Kyung-Ae;Song, Sung-Jun;Lee, Sun-Joo;Lee, Young-Il;U., Zang-Kual
    • Korean Journal of Environmental Agriculture
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    • v.22 no.4
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    • pp.294-299
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    • 2003
  • The seeds of naturally growing Heteropappus hispidus (Thunb.) were treated by nine different doses (0, 10, 20, 40, 80, 120, 160, 200, 300, 400 Gy) of gamma rays to investigate their germination rate and to quantity the characteristics of their germinated plants as like as leaf appearance and length, the formation rate of anthocyanin color in stem 30 days after germination, the formation rate of rosette leaf and multi-shoot, the flowering and seed-bearing, and shoot length. The germination rate at least up to 120Gy was not greatly affected but was rapidly decreased at over 160Gy. It seemed that lethal dose ($LD_{50}$) of germination was 160Gy. The leaf appearance and growth was also inhibited, but the formation rate of anthocyanin color in the flower stem was enhanced up to 30% with dose. The rosette plants were observed in plants irradiated with higher than 40Gy. Multi-shoots were developed over 80Gy. For a short shoot length and bundle of thin stem, it was considered that they can be selected as the potential pot flower plants, through genetic fixation. In particular, it was suggested that the formation of anthocyanin color in flower stem, rosette and multi-shoot plants induced by the high dose of gamma rays could be utilized as the morphological markers for the mutant selection of Heteropappus hispidus (Thunb.).

Effects of Gamma-ray Irradiation on Growth Characteristics and DNA Damage in Licorice (Glycyrrhiza uralensis) (감마선 조사가 감초(Glycyrrhiza uralensis)의 초기 생육 및 DNA 손상에 미치는 영향)

  • Ryu, Jaihyunk;Im, Seung Bin;Kim, Dong Sub;Ahn, Joon-Woo;Kim, Jin-Baek;Kim, Sang Hoon;Kang, Si-Yong
    • Journal of Radiation Industry
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    • v.8 no.2
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    • pp.89-95
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    • 2014
  • This study was conducted to determine the optimal dose of gamma-ray on the growth and nucleus DNA damage for mutation breeding in licorice. Gamma-rays irradiated to dry seeds with various doses (0 to 1000 Gy). Significant decreases in germination rate (%), survival rate (%) and growth characteristics (plant height, number of leaves, root length and fresh weight) were observed by dose of increased. $LD_{50}$ (lethal dose) was approximately 400 Gy to 500 Gy. Also, reduction doses ($RD_{50}$) of plant height, number of leaves, root length and flash weight were 428 Gy, 760 Gy, 363 Gy and 334 Gy, respectively. It is supplest that the optimal dose of gamma irradiation for licorice mutation induction might be about 400 Gy in this study. We also conducted comet assay to observe nucleus DNA damage due to gamma irradiation. In comet assay, a clear difference was identified over 300 Gy treatments. With increasing doses of gamma-ray in the range of 100 to 1000 Gy, the rate of head DNA was decreased significantly from 92.88% to 73.09%. Tail length(${\mu}m$) was increased as the dose of increased over 300 Gy. Growth characteristics (Germination rate, Survival rate, plant height, number of leaves, root length and fresh weight) were highly negatively ($P{\leq}0.01$) correlated with dose. While the tail length was highly positively ($P{\leq}0.01$) correlated with dose.

The impact of chlorothalonil on female gametophyte survival rate and relative growth rate of Undaria pinnatifida (Chlorothalonil이 미역(Undaria pinnatifida) 배우체의 생존 및 상대성장률에 미치는 영향)

  • Yun-Ho Park;Bo-Ram Sim;Un-Ki Hwang;Ju-Wook Lee
    • Korean Journal of Environmental Biology
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    • v.41 no.3
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    • pp.256-265
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    • 2023
  • Chlorothalonil is continuously introduced into the marine environment and has significant toxic effects on various marine organisms, however, research on its effect on seaweed is limited. Therefore, we analyzed the impact of chlorothalonil on the early life stages of major aquaculture species in Korea, Undaria pinnatifida. U. pinnatifida female gametophytes were exposed to different concentrations of chlorothalonil (0, 0.03, 0.05, 0.10, 0.20, and 0.40 mg L-1), and their survival rate and relative growth rate were analyzed. The no observed effect concentration (NOEC), lowest observed effect concentration (LOEC), and median lethal concentration (LC50) for female gametophyte survival were determined as 0.05, 0.10, and 0.141(0.121-0.166)mg L-1. NOEC, LOEC, and median effective concentration (EC50) for relative growth rate were 0.10, 0.20, and 0.124 (0.119-0.131) mg L-1. Therefore, female gametophytes of U. pinnatifida are expected to experience toxic effects at concentrations above 0.05-0.10 mg L-1 of chlorothalonil. These research findings are anticipated to serve as crucial reference data for evaluating the effects of chlorothalonil on the health of U. pinnatifida in the early life stages.

Effect of Sorbitol on the Texture and the Survival of Lactic Acid Bacteria of Frozen Yoghurt (Sorbitol첨가가 Frozen Yoghurt중 유산균의 생존율과 조직에 미치는 영향)

  • Kim, Eung-Ryul;Kim, Yu-Seong;Lee, Yeong-Geon;Ju, Ji-Seon;Lee, Gang-Ik;Baick, Seung-Cheon;Lee, Jong-Ik;Yu, Je-Hyeon
    • Journal of Dairy Science and Biotechnology
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    • v.14 no.1
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    • pp.71-84
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    • 1996
  • This study was conducted to examine the usability of sorbitol for the manufacture as low-calory ingredient and cryoprotectant against frost damage. When frozen yoghrt was made of replacing sucrose by sorbitol at yoghurt mix, the change of physicochemical and lactic acid bacteria, such as Str. thermophilus, L. bulgaricus, and mixed culture of Str. thermophilus, and L. bulgaricus(1:1), was studied during the frozen storage(-20$^{\circ}$C). During the incubation of yoghurt mix, the rapid growth of lactic acid bacteria in all sample was observed as the increase of sorbitol addition, but sample A and D were almost similar. This results suggested that sucrose could play role of effecting the growth stimulator, otherwise, sorbitol could inhibit the death of microorganism, following the genus. At the survival rate between lactic acid bacteria during freezing of -5$^{\circ}$C by ice cream freezer Str. thermophilus showed 26.19 to 34.76%, L. bulgaricus 3.97 to 5.20%, and mixed culture 17.16 to 40.87% respectively. L. bulgaricus showed the greater lethal rate than other genus. Sample C which mixed sucrose with sorbitol (1:2 ratio) was showed the lowest lethal rate. Therefore, it suggested that the use of this ration could be used for better anti-frost damage. During the storage of -20$^{\circ}$C, the number of lactic acid bacteria generally decreased in the stand point of genus and frozen storage period. The survival of lactic acid bacteria might be the addition of sorbitol which could have the effect of anti-forst damage. In all treatment, lactase activity showed the rapid decrease after freezing. During the period of frozen storage, it was shown the slow decreasing trend. In spite· of decreasing, the result during yoghurt mix incubation -5$^{\circ}$C freezing, and -20$^{\circ}$C frozen storage was different at the level. After 80 days of storage, the lactase activity was similar among all genus and sample. Despite differenting viscosity followed by genus, combination of mix, and pH, the ratio of 1 to 2(sucrose : sorbitol) showed the greatest viscosity. The water holding capacity of frozen yoghurt mix was closely related to viscosity. As increasing sorbitol amounts, hardness and cohesiveness were increased, but elastisity was decreased. The significant differences between sample was inoculated with Str. thermophilus. However, there were not significant difference from the sample inoculated with L. bulgaricus and mixed culture.

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Effects of External Whole-Body gamma-Irradiation on Blood Picture and Growth in Young Rabbits (Cobalt-60 gamma 선(線) 외부전신조사(外部全身照射)가 어린 토끼의 혈액상(血液像)과 성장률(成長率)에 미치는 영향(影響))

  • Sung, Jai Ki
    • Korean Journal of Veterinary Research
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    • v.13 no.1
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    • pp.85-102
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    • 1973
  • In the event a population of animals is exposed to ionizing radiation, proper disposition of animals will minimize loss to the farmer and protect the public from unwholesome meat and dairy products. Clinical response is an important factor in considering salvage of animals for food following exposure to ionizing radiation whether the dose is lethal or not. It is the purpose of this report to present the discussions of blood picture and growth of y ung growing rabbits exposed to cobalt-60 gamma-irradiation. The experimental animals were Hyrnalayan rabbits of 65 days old. The body weight for all animals of the time of irradiation was approximately 450g. The 96 rabbits used in the experiment were allotted t groups of eight. Rabbits in one group served as controls and the others were exposed to single doses of 100, 200, 300, 400, 500, 600 and 700 Roentgens (R). The exposure does rate averaged 15 R per minute. Central blood was obtained by heart puncture. Erythrocyte and leukocyte enumerations and, determinations of hemoglobin in blood and hematocrit value were made in the usual manner. Erythrocyte counts, concentrations of hemoglobin in blood, and hematocrit readings dropped to the lowest value between 1 and 4 weeks postirradiation, returning towards the control values. But recovery was not complete at the time of the last determination on 6 weeks postirradiation. There was a progressive decrease with increasing radiation does in the above values. Mean corpuscular volume, mean corpuscular hemoglobin and mean corpuscular hemoglobin concentration were not affected by the irradiation. After irradiation of each does the numbers of total leukocyte and the absolute numbers of various types of white cell began to decrease rapidly, and reached a minimum after 2 weeks, returning towards normal levels. But recovery was not complete at the time of the last determination on 6 weeks postirradiation. The reductions in total leukocyte and differential counts as the radiation does increases were apparent. Relative neutrophilia was observed in each irradiated group because of more expense of lymphocytes after irradiation. Growth rate of the rabbits was not affected by 100 R of whloe-body irradiation, while rabbits irradiated with 200, 300, 400 and 500 R showed marked depression of growth rate. As the radiation does increases, a depression of growth rate was apparent. The rabbits exposed to 600 and 700 R ceased from growing and recovery was not recognized during the experimental period.

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