• Title/Summary/Keyword: induction periods

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Ecological Aspect of Perennial Weeds which were Grown in Transplanted Paddy Field -The Effects of Day Length on Tuber Formation and Tuber Cutting and Soil Depth Covered on New Shoot Development of Perennial Weeds- (논에 발생하는 주요 다년생잡초 생태에 관한 연구 -일장처리가 지하경 형성에 미치는 영향과 지하경 절단정도별, 수분조건별, 토심별에 따른 맹아 발생력에 관한 연구-)

  • Soon-Chul Kim;Sang-Yull Jae
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.22 no.1
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    • pp.70-79
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    • 1977
  • Perennial weeds which were grown in transplanted paddy field formed their tubers under shortday condition. Under short day treatment, the induction periods for tuber formation were different depending upon the weed species. 80% cut tubers of the weeds did not loose their developing ability perfectly. Emergence also affected by soil conditions and depths covered.

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Genomic Variations of Rice Regenerants from Tissue Culture Revealed by Whole Genome Re-Sequencing

  • Qin, Yang;Shin, Kong-Sik;Woo, Hee-Jong;Lim, Myung-Ho
    • Plant Breeding and Biotechnology
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    • v.6 no.4
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    • pp.426-433
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    • 2018
  • Plant tissue culture is a technique that has invariably been used for various purposes such as obtaining transgenic plants for crop improvement or functional analysis of genes. However, this process can be associated with a variety of genetic and epigenetic instabilities in regenerated plants, termed as somaclonal variation. In this study, we investigated mutation spectrum, chromosomal distributions of nucleotide substitution types of single-nucleotide polymorphisms (SNPs) and insertions/deletions (InDels) by whole genome re-sequencing between Dongjin and Nipponbare along with regenerated plants of Dongjin from different induction periods. Results indicated that molecular spectrum of mutations in regenerated rice against Dongjin genome ranged from $9.14{\times}10^{-5}$ to $1.37{\times}10^{-4}$ during one- to three-month callus inductions, while natural mutation rate between Dongjin and Nipponbare genomes was $6.97{\times}10^{-4}$. Non-random chromosome distribution of SNP and InDel was observed in both regenerants and Dongjin genomes, with the highest densities on chromosome 11. The transition to transversion ratio was 2.25 in common SNPs of regenerants against Dongjin genome with the highest C/T transition frequency, which was similar to that of Dongjin against Nipponbare genome.

Callus Induction and Differentiation from Rice (Oryza Sativa L.) Anthers (벼 약(葯)으로부터 callus 형성(形成)과 분화(分化)에 대(對)하여)

  • Kim, Dal Ung;Bae, Min Gyu
    • Current Research on Agriculture and Life Sciences
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    • v.1
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    • pp.1-9
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    • 1983
  • This study was conducted to obtain basic information on the rice anther culture. Materials used were (Inabawase X YR 2404-14-2-1) $F_1$ hybrid. Callus growth rate on various media, induction frequency of callus in spikelet and panicle, and the effect of treatment on anther and callus were evaluated. The results obtained were summarized as follows ; The growth rate of callus on N-6, M-S, P.E.agar media was 19.8, 13.1, 4.1 times respectively after 30 days inoculated, and on liquid media was 3.8, 5.1, 1.4 times, respectively. Organ differentiation on N-6, M-S, P.E.agar media was 37.5%, 12.5%, 17.5% respectively. The difference of induction frequency of callus per panicle was 0.14%-6.25% and per spikelet was 0-19.05%. Almost callus was induced 30-35 days after inoculation. Organ differentiation of induced callus was decreased by culture. Callus cultured for 13 days after induction did not make shoot. Anthers cold shocked at $8^{\circ}C$ for 5 days obtained 3.32% efficiencys of callus induction per number of anthers plated, and compared with 2.41% of no treated anthers. But anther treated at $8^{\circ}C$ for 7 days decreased 2.24%. Callus induction periods were shortened by cold treatment for about 5 days. Callus cultured on medium containing 2 mg/l of 2, 4-D showed 5% on root formation but medium containing 5 mg/l of 2, 4-D showed 30% of root formation after transfered on the medium without 2, 4-D. Callus cold shocked at $15-18^{\circ}C$ revealed poor efficiency for root formation, but 5 days treatment was good for shoot formation.

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Effects of 0.1% Tacrolimus on Canine Skin Mast Cells and Eosinophils (개에서 0.1% FK-506 연고의 피부 비만세포와 호산구에 미치는 영향)

  • Jeong, A Young;Bae, Seulgi;Oh, Taeho
    • Journal of Veterinary Clinics
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    • v.31 no.2
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    • pp.95-101
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    • 2014
  • Five dogs were used to determine whether 0.1% tacrolimus ointment application for one day would inhibit IgE-mediated late-phase reactions (LPRs). It was consisted of three periods: one period without therapeutic administration (control) and two periods of treatment with either the tacrolimus ointment or vehicle. Induction of IgE-mediated LPRs was induced by intradermal injections of 0.05 ml (0.14 mg/ml) of solution of goat anti-canine IgE polyclonal antibodies. Each section for mast cells (MCs) and eosinophils (EPs) was stained with acidified toluidine blue, and Luna's stain, respectively. Assessment of anti-inflammatory effect of tacrolimus ointment composed of cell counts of MC and EP from lesions of induced LPR. In normal canine biopsies, the number of dermal MCs and EPs were $12.3{\pm}1.4cells/mm^2$ and $3.1{\pm}1.3cells/mm^2$, respectively. MC counts dramatically decreased at time dependent manner after anti-IgE administration. However, the number of MCs on 6 hours after challenge was significantly less decreased in the groups treated with the tacrolimus, as compared with control and vehicle group. The number of EPs on 24 hours after challenge was significantly lower in the group treated with the tacrolimus than in the control and vehicle groups. In conclusion, this study revealed that 0.1% tacrolimus ointment in dogs may exert a potent anti-inflammatory effect on inhibition of MC degranulation and also secondary prevention of EP infiltration during LPR.

Effect of Soy Isoflavones on the Expression of $TGF-{\beta}1$ and Its Receptors in Cultured Human Breast Cancer Cell Lines

  • Kim Young-Hwa;Jin Kyong-Suk;Lee Yong-Woo
    • Biomedical Science Letters
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    • v.11 no.2
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    • pp.175-183
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    • 2005
  • The two major isoflavones in soy, genistein and daidzein, are well known to prevent hormone-dependent cancers by their anti estrogenic activity. The exact molecular mechanisms for the protective action are, however, not provided yet. It has been reported that genistein and daidzein have a potential anticancer activity through their antiproliferative effect in many hormone-dependent cancer cell lines. Transforming growth $factor-\beta1(TGF-\beta1)$ has also been found to have cell growth inhibitory effect, especially in mammary epithelial cells. This knowledge led to a hypothetical mechanism that the soy isoflavones-induced growth inhibitory effect can be derived from the regulation of $TGF-\beta1$ and $TGF-\beta$ receptors. In order to test this hypothesis, the effects of the soy isoflavones at various concentrations and periods on the expression of $TGF-\beta1$and $TGF-\beta$ receptors were investigated by using Northern blot analysis in human breast carcinoma epithelial cell lines, an estrogen receptor positive cell line (MCF-7) and an estrogen receptor negative cell line (MDA-MB-231). As a result, only genistein has shown a profound dose-dependent effect on $TGF-\beta1$ expression in the $ER^+$ cell line within the range of doses tested, and the expression levels are correspondent to their inhibitory activities of cell growth. Moreover, daidzein showed down-regulated $TGF-\beta1$ expression at a low dose, the cell growth proliferation was promoted at the same condition. Therefore, antiproliferative activity of the soy isoflavones can be mediated by $TGF-\beta1$ expression, and the effects are mainly, if not all, occurred by ER dependent pathway. The expression of $TGF-\beta$ receptors was induced at a lower dose than the one for $TGF-{\beta}1$ induction regardless of the presence of ER, and the expression patterns are similar to those of the cell growth inhibition. These results indicated that the regulation of $TGF-\beta$ receptor expression as well, prior to $TGF-\beta1$ expression, may be involved in the antiproliferative activity of soy isoflavones. Little or no expression of $TGF-\beta$ receptors was found in the MCF-7 and MDA-MB-231 cells, suggesting refractory properties of the cells to growth inhibitory effect of the $TGF-\beta$. The soy isoflavones can seemingly restore the sensitivity of growth inhibitory responses to $TGF-\beta1$ by re-inducing $TGF-\beta$ receptors expression. In conclusions, our findings presented in this study show that the antitumorigenic activity of the soy isoflavones could be mediated by not only $TGF-\beta1$induction but $TGF-\beta$ receptor restoration. Thus, soy isoflavones could be good model molecules to develop new nonsteroidal antiestrogenic chemopreventive agents, associated with, regulation of $TGF-\beta$ and its receptors.

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Reproductive Cycle and Induced Sexual Maturation of the Pacific Oyster, Crassostrea gigas (참굴, Crassostrea gigas의 생식주기와 성 성숙 유도)

  • Min, Kwang-Sik;Kim, Bong-Seok;Kim, Tae-Ik;Hur, Young-Baek;Chung, Ee-Yung
    • The Korean Journal of Malacology
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    • v.20 no.1
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    • pp.75-84
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    • 2004
  • Reproductive cycle, the condition index, sex ratio of the Pacific oysters, Crassostrea gigas were investigated by histological and morphometric data. The specimens were collected in the two oyster farms of Geoje and Namhae, Gyeongsangnam-do, Korea, from November 1995 to October 1996. Growth of shell length in two regions was similar, but growth of total weight of the oyster in Namhae was faster than that in Geoje oyster farm. The spawning periods in female and male clams were from July to October in Geoje and from June to October in Namhae oyster farm. Ripe oocytes were approximately 50 m in diameter. The reproductive cycle of in females and males in Geoje and Namhae oyster farms can be divided into five successive stages: early developing, late developing, ripe, partially spawned and spent/inactive. Monthly changes in gonad developmental phases showed somewhat different patterns between female and male clams except for the spawning period. On the whole, however, monthly changes in the gonad developmental phases showed a similar pattern in the same sex. The sex ratios of females to males in Geoje and Namhae oyster farms were not significantly different from a 1:1 sex ratio ($x^2$ = 0.55 (p > 0.05) in Geoje and $x^2$ = 0.27 ( p > 0.05) in Namhae). Artificial induction of maturation by heating of adult oysters (two-year-old) was investigated from 17 January to 18 March in 1996. Maturity at the fixed water temperature group of $20^{\circ}C$ was 80%, it showed the highest maturity of experimental groups cultured for five weeks. The survival (%) of Crassostrea gigas in the raised water temperature experimental groups (15, 20, $25^{\circ}C$) were over 98.5%, as similar to the control group (100%). But, the survival of C. gigas in the fixed water temperature experimental groups (15, 20, 25, $30^{\circ}C$) were decreased with the increase of the water temperatures. In the fixed water temperature experimental group of $30^{\circ}C$, the survival was 51.1%. Base on these results, the fixed water temperature of $20^{\circ}C$ was the best condition for artificial induction of sexual maturation.

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Effects of Plant Growth Regulators on In Vitro Germination and Organ Formation of Wild Angelica gigas N. (야생 참당귀(Angelica gigas N.)의 기내발아 및 기관유도에 미치는 PGRs의 영향)

  • Lee, Su-Gwang;Cho, Won-Woo;Lee, Song-Hee;Park, Kwang-Woo;Choi, Kyung;Kang, Ho-Duck
    • Korean Journal of Plant Resources
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    • v.25 no.4
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    • pp.456-464
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    • 2012
  • This study was conducted to establish the in vitro optimal condition for seed germination and organogenesis of wild Angelica gigas. The experiment was evaluated the effects of $GA_3$ for pre-treatment with different periods of time (0h, 24h, 48h, 72h) and followed the treatment of seeds by control, scarification and methanol-heating method. As a result, the highest rates (15%) of seed germination was shown under the treatment without soaking of $GA_3$ and methanol-heating treatment. The seed germination was highly increased 60% under the condition of treatment on ultrasonic waves (frequency 80 KHz) with methanol-heating treatment including 0.1 mg/L $GA_3$. The highest callus induction rate was obtained from in vitro germinated stem, root and hypocotyl on the MS medium with 1.0 mg/L NAA and 0.5 mg/L BA. The highest percentages of shooting (50%) and rooting (85%) induction were observed in hypocotyl and root cultured on PGRs free medium and 0.1 mg/L NAA, respectively. In addition, somatic embryogenesis was observed from stem (1.0 mg/L 2,4-D) and hypocotyl (0.1 mg/L NAA).

Oxidative Stability of Sesame Oil Prepared from Black Sesame Flour (흑참깨분으로 착유한 참기름의 산화안정성)

  • Nam, Mi-Jin;Chung, Ha-Yull
    • Korean Journal of Food Science and Technology
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    • v.40 no.2
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    • pp.141-145
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    • 2008
  • Oxidative stabilities of sesame oil prepared from black sesame flour and white sesame flour, and commercial sesame oil prepared from whole white sesame were compared by measuring oxidation induction periods, peroxide values and electron donating abilities of each oil. Oxidation induction period (12.25 hr) of sesame oil prepared from black sesame flour was longer than those (4.37 and 9.1 hr, respectively) of sesame oil from white sesame flour and commercial sesame oil. Peroxide values of sesame oil prepared from black sesame flour, sesame oil prepared from white sesame flour and commercial sesame oil were 1.3, 18.2 and 1.7 meq/kg oil, respectively. We ascertained that the oxidative stability of sesame oil prepared from black sesame flour was superior than sesame oil from white sesame flour as well as ommercial sesame oil. This was based on the fact that electron donating ability of sesame oil prepared from black sesame flour was 9% higher than that of sesame oil prepared from white sesame flour at the same concentration. The superior oxidative stability of sesame oil prepared from black sesame flour was expected, not only because only it had lignans such as sesamol and sesamolin, but also because of its brownish coloring compounds such as tannin which were not contained in white sesame flour.

Comparative Study on the Infection Rates of Protected Environment versus Non-Protected Environment in Acute Myeloid Leukemia during Remission Induction Chemotherapy (급성 백혈병 환자에서 관해 유도 치료 시 일반 병실과 보호된 환경의 감염률 비교)

  • Sohn, Se-Hoon;Lee, Ha-Young;Kim, Dong-Geun;Park, Sung-Woo;Kim, Myung-Jin;Oh, Myung-Jin;Woo, Hye-Deok;Ryoo, Hun-Mo;Bae, Sung-Hwa;Lee, Kyung-Hee;Kim, Min-Kyoung;Hyun, Myung-Soo
    • Journal of Yeungnam Medical Science
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    • v.27 no.2
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    • pp.113-121
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    • 2010
  • Background and purpose : Patients with acute leukemia experience prolonged periods of neutropenia due to their disease or its treatment. For this reason, they often develop serious infectious complications. Although antibiotic therapy has improved in recent years, the fatality rate from infection remains high. For the control of infection, protected environment was developed. But because of economic issue, most of chemotherapy with acute myeloid leukemia have conducted in non-protected environment. So this study compared the rate of complete remission, days with neutropenia, rate of fever, rate of positive culture, rate of overt infection and use of antibacterial and antifungal agents with patients within non-protected environment and protected environment, retrospectively, Patients with acute myeloid leukemia during first remission induction chemotherapy were eligible for this study, Methods : Retrospective analysis was conducted between patients in non-protected (25 patients) and protected environment (14 patients) with acute myeloid leukemia during remission induction chemotherapy Results : Rate of overt infection, rate of fever, rate of positive culture and rate of use of antibiotics were significantly high in patients within non-protected environment compared with patients within protected environment. There were no differences in rate of complete remission and days of neutropenia Conclusions : This study suggests protected environment for patients with acute myeloid leukemia during remission induction chemotherapy could reduce rate of overt infection, and rate of use of antibiotics.

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Antioxidative Activity of Rooibos Tea(Aspalathus linearis) Extracts (용매에 따른 Rooibos Tea(Aspalathus lineais) 추출물의 항산화 효과)

  • Lee, Cho-Rong;Lee, Jeung-Hee;Park, Sang-Hyun;Lee, Ki-Teak
    • Food Science and Preservation
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    • v.15 no.4
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    • pp.582-586
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    • 2008
  • Total phenolic compounds and antioxidative activities of rooibos tea(Aspalathus linearis) fractions were studied. Three extracts, using hexane, ethyl acetate, and ethanol, were prepared. Total phenolic compounds were 3069.3 mg/100 g extract in the hexane fraction, 18604.4 mg/100 g extract in the ethyl acetate fraction, and 13458.8 mg/100 g extract in the ethanol fraction. Levels of vanillic acid, caffeic acid, syringic acid, 4-coumaric acid, and ferulic acid were analyzed by RP-HPLC, and totals of 3452.6 and 3156.1 mg/100 g of extract were found in the ethanol and ethyl acetate fraction, respectively. In the DPPH assay, the ethanol fraction(82.2% of contol) and the ethyl acetate fraction(78.9%) showed the highest free radical scavenging capacities. The induction period of each tea fraction in the fish oil rancimat assay was measured. When 500 ppm of the ethanol fraction was applied, a 1.19 h induction period was observed. This was 2-fold greater than the induction period of the control.