• Journal of Life Science
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• v.24 no.10
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• pp.1137-1143
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• 2014

Doxorubicin is a general chemotherapy drug widely used for a number of cancers. However, the correlation between endogenous nitric oxide ($NO^{\bullet}$) levels and chemoresistance to doxorubicin remains unclear. In this study, we investigated the effect of endogenous $NO^{\bullet}$ on the anticancer activity of doxorubicin in human colon cancer cell lines HCT116 and HT29 with different p53 status. The cells were treated with either doxorubicin alone or in combination with the $NO^{\bullet}$ synthase (NOS) inhibitor $N^G$-monomethyl-L-arginine (NMA). Doxorubicin differentially inhibited the growth of both the HCT116 (p53-WT) and HT29 (p53-MUT) cells, which was mitigated by cotreatment with NMA. Further studies revealed that inhibition of endogenous $NO^{\bullet}$ mitigated doxorubicin-induced apoptosis in the HCT116 and HT29 cells, as evidenced by apoptotic DNA fragmentation and the sub-G1 peak of apoptotic markers. Apoptosis was delayed in the HT29 cells, and its magnitude was greatly reduced, underscoring the importance of the modulation of p53 in the response. RT-PCR analysis revealed that doxorubicin down-regulated levels of inhibitors of the apoptosis family (cellular IAP-1 and-2). Collectively, these data show that induction of apoptosis by doxorubicin in human colon cancer cells is possibly related to modulation of endogenous $NO^{\bullet}$, the expression of the IAP family of genes, and the status of p53. The underlying mechanisms may represent potential targets for adjuvant strategies to improve the efficacy of chemotherapy for colon cancer.

• Journal of Bio-Environment Control
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• v.21 no.1
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• pp.28-32
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• 2012

This study was conducted to improve year round production of onion sets for pickles and increase their yield by using different cell sizes of plug trays. 'Josaeng sseondeobol' and 'Daeji' were seeded in 105-cell tray, 128-cell tray, and 162-cell tray on March 27, 2010. 'Josaeng sseondeobol' showed the maximum number of leaves on May 23, but 'Daeji' showed the maximum in late June. Bulbing of 'Josaeng sseondeobol' was already initiated on May 23, but 'Daeji' was initiated on June 6. Growth of both varieties was better in 105-cell tray than the others. There wasn't a difference in bulbing between two varieties by the number of cells, but bulb size was larger in the low number of cells than high ones. 'Josaeng sseondeobol' was all harvested in July, but more than 50% of 'Daeji' was harvested in August. The result of this study is as follows. Harvest time was delayed as the number of cells is increasing. There was a wide range of small onion sets distribution in both varieties as the number of cells is increasing.

• Research in Plant Disease
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• v.23 no.3
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• pp.256-261
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• 2017

The effects of insecticide and fungicide treatment were investigated to reduce mycotoxin contamination of corn (Zea mays L.) seeds. Deoxynivalenol and zearalenone contents were reduced in the treated seeds, but aflatoxin, ochratoxin A, fumonisin, and T-2 toxin were not effective by chemical treatments. The chemical treatment did not affect the growth of saprophyte, but inhibited the pathogenic fungi such as Fusarium verticillioides, F. graminearum and F. equiseti. Myotoxin contents at different harvesting time were compared. As the harvest time was delayed, both levels of deoxynivalenol and zearalenone and frequency of Fusarium spp. increased. However, the major nutrient contents of corn seeds were not affected by harvesting period. These results show that chemical treatments are necessary to reduce the fungal contamination of corn and harvest without delay is important as well.

• Korean Journal of Weed Science
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• v.8 no.2
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• pp.158-163
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• 1988

Several factors affecting emergence and tuber formation of lowland perennial weeds were studied at the Yeongnam Crop Experiment Station in 1988. Period of tuber germination start to final tuber varied by species. Eleocharis kuroguwai and Sagittaria trifolia required longer than 10 days at $30^{\circ}C$ for this while Cyperus serotinus and S. pygmaea needed about 4 days. Application of gibberellic acid shortened this period while Uniconazole application delayed. E. kuroguwai and C. serotinus had ability to emerge under 20cm depth placement. However, S. trifolia could not emerge under 15cm depth. All species decreased their growth with increase in planting depth. E. kuroguwai had least correlated between dry matter production and tuber formation. Clipping of above ground part negatively related with tuber formation eventhough the effect of clipping time was differed by species. The most critical clipping time was 60 days after eremergence (DAE) for E. kuroguwai and 90 DAE for C. serotinus. Covering of colored polyethylene film was also related with tuber formation with varing effects. In general, the order of effectiveness for tuber formation were black. orange. blue and red. Application of Uniconazole and Pachlobutrazol effectively controlled the formation of tuber of E. kuroguwai and this effect enhanced by early application.

• Korean Journal of Soil Science and Fertilizer
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• v.25 no.4
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• pp.378-386
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• 1992

This experiment was conducted to investigate the effects of inoculation of the Bradyrhizobium sp.(Arachis) HCR-46 and fertilizer nitrogen application on nodulation, $N_2$-fixation of cowpea group legume(Seowon dongbu, Seonwha nogdu, Chungju pat, Youngho tangkong). Treatments consisted of five uninoc.+N : O, uninoc.+N : 6kg/10a. inoc.+N : O, inoc.+ N : 6kg/10a, inoc.+N : 12kg/10a. 1. Initial nodulation time of cowpea group legume by inoculation of Bradyrhizobium sp. HCR-46 was 12~21 days, and it was delayed as more fertilizer nitrogen was added. 2. The number and dry weight of nodule were increased as growth period elapsed, but decreased as fertilizer nitrogen was added. 3. Dry matter production and amount of nitrogen uptake were increased by inoculation and the effects of inoculation were increased when fertilizer nitrogen of 6kg/10a was applied. 4. Amount of fixed nitrogen by inoculation of fertilizer nitrogen not applied was higher than the case of 6kg/10a applied and that of peanut was higher than the other legumes(cowpea, mung bean and adzuki).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.37 no.5
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• pp.461-467
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• 1992

A mungbean cultivar, 'Seonhwanogdu', was seeded on April 20, May 10, June 1, June 20, July 10 and July 30 in 1988, 1989 and 1990 to determine the optimum seeding date of mungbean in Cheju province. As seeding was delayed from April 20 to June 20, the number of days from emergence to first flowering (days to flowering) decreased from 56.7 to 36.7 days, on the three year average. Days to flowering of mungbean seeded on July 10 and 30 ranged 30 to 35 days except that of the plants seeded on July 10, 1988. Days to flowering linearly decreased as the average of daily mean air temperature from emergence to the first flowering increased. The number of days from the first flowering to the first maturity (days to maturity) in mungbean seeded on April 20 to July 10 ranged 14 to 21 days and was 29 to 40 days at the July 30 seeding. The number of pods per plant, the number of seeds per pod, 1000 seed weight and yield tended to increase with delaying seeding up to June 1 and June 20, and then to decrease with further delaying seeding. This study indicates that the optimum seeding time of mungbean in Cheju province is around mid-June.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.3
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• pp.230-235
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• 1999

To study the effects of an urease inhibitor, N-(n-butyl)-thiophosphoric triamide (NBPT), and a nitrification inhibitor, dicyandiamide (DCD), on nitrogen losses and nitrogen use efficiency, urea fertilizer with or without inhibitors and slowrelease fertilizer (synthetic thermoplastic resins coated urea) were applied to direct-seeded flooded rice fields in 1998. In the urea and the urea+DCD treatments, NH$_4$$^{+}$ -N concentrations reached 50 mg N L$^{-1}$ after application. Urea+NBPT and urea+ NBPT+DCD treatments maintained NH$_4$$^{+}$ -N concentrations below 10 mg N L$^{-1}$ in the floodwater, while the slow-release fertilizer application maintained the lowest concentration of NH$_4$$^{+}$ -N in floodwater. The ammonia losses of urea+NBPT and urea+NBPT+DCD treatments were lower than those of urea and urea+DCD treatments during the 30 days after fertilizer application. It was found that N loss due to ammonia volatilization was minimized in the treatments of NBPT with urea and the slow-release fertilizer. The volatile loss of urea+DCD treatment was not significantly different from that of urea surface application. It was found that NBPT delayed urea hydrolysis and then decreased losses due to ammonia volatilization. DCD, a nitrification inhibitor, had no significant effect on ammonia loss under flooded conditions. The slow-release fertilizer application reduced ammonia volatilization loss most effectively. As N0$_3$$^{[-10]}$ -N concentrations in the soil water indicated that leaching losses of N were negligible, DCD was not effective in inhibiting nitrification in the flooded soil. The amount of N in plants was especially low in the slow-release fertilizer treatment during the early growth stage for 15 days after fertilization. The amount of N in the rice plants, however, was higher in the slow-release fertilizer treatment than in other treatments at harvest. Grain yields in the treatments of slow-release fertilizer, urea+NBPT+ DCD and urea+NBPT were significantly higher than those in the treatments of urea and urea+DCD. NBPT treatment with urea and the slow-release fertilizer application were effective in both reducing nitrogen losses and increasing grain yield by improving N use efficiency in direct-seeded flooded rice field.field.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.2
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• pp.223-229
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• 1996

To investigate the effect of seeding date, seeding rate, and sprouted seeds on seedling establishment, yield and its components of rice in barley /rice reley cropping as a minimum tillage, Gancheokbyeo rice seeds sowed by hand broadcast in various overlapped days befer barley harvest. The highest rice seedling stand was at sowed on the day just before barley harvest and l00kg per hectare of seeding rate with sprouted seeds. Also number of tiller and panicle showed the similar tendency. Delayed rice heading dates were found 2 days at l0-day overlap, 2 days at 5-day overlap, and 4 days at 0-day overlap before barley harvest compared with machine transplanting rice at just after barley harvest using l0-days old seedling. The culm length of broadcast rice shortened 2∼4cm compared with the transplanting rice. The rice plants lodged slightly at seeding rate l00kg per hectare and at sowed on the day of barley harvest. The rice panicle number increased with later date sowing and higher seeding rate. Number of spikelets per panicle and ripened grains decreased at higher seeding rates. Sprouted seeds and higher seeding rates showed higher rice yield at later sowing dates.

• The Korean Journal of Pesticide Science
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• v.6 no.1
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• pp.36-41
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• 2002

Characteristics of regrowth and starch degradation in perennial weed rhizomes were investigated in a greenhouse. Cyperus serotinus started regrowth at 24 days after treatment of 1.25 g ai/ha of pyrazosulfuron-ethyl. The regrowth of Sagittaria trifolia, Eleocharis kuroguwai, and S. pygmaea required $30{\sim}39$ days, and Potamogeton distinctus regrew at 55 days after treatment of 1.25 g ai/ha of pyrazosulfuron-ethyl. However, all of 5 perennial weeds hardly regrew until 45 days after treatment more than 5 g ai/ha of pyrazosulfuron-ethyl. Regrowth of C. serotinus 4-node rhizomes was 2 times higher than 2-node rhizomes, and $1{\sim}1.5g$ of E. kuroguwai large tubers regrew faster than $0.3{\sim}0.5g$ of small tubers treated with bensulfuron-methyl. Regrowth of C. serotinus was enhanced with delayed application of bensulfuron-methyl, however, 2-leaf stage of E. kuroguwai plants regrew better than 3 leaf stage of plants when treated with equal volume of bensulfuron-methyl. The critical periods of S. trifolia and E. kuroguwai growth depending upon the rhizome detachment were 12 and 18 days after sprouting, respectively. The starch stacked in the S. trifolia and E. kuroguwai tubers were exhausted at 18 and 27 days after sprouting, respectively. The highest level of sugar contents was showed at 9 days after sprouting in S. trifolia, and 18 days after sprouting in E. kuroguwai.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.11
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• pp.1649-1656
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• 2015

Gene expression profiling has offered new insights into postmortem molecular changes associated with meat quality. To acquire reliable transcript quantification, high quality RNA is required. The objective of this study was to analyze integrity of RNA isolated from chicken skeletal muscle (pectoralis major) and its capability of serving as the template in quantitative real-time polymerase chain reaction (qPCR) as a function of postmortem intervals representing the end-points of evisceration, carcass chilling and aging stages in chicken abattoirs. Chicken breast muscle was dissected from the carcasses (n = 6) immediately after evisceration, and one-third of each sample was instantly snap-frozen and labeled as 20 min postmortem. The remaining muscle was stored on ice until the next rounds of sample collection (1.5 h and 6 h postmortem). The delayed postmortem duration did not significantly affect $A_{260}/A_{280}$ and $A_{260}/A_{230}$ ($p{\geq}0.05$), suggesting no altered purity of total RNA. Apart from a slight decrease in the 28s:18s ribosomal RNA ratio in 1.5 h samples (p<0.05), the value was not statistically different between 20 min and 6 h samples ($p{\geq}0.05$), indicating intact total RNA up to 6 h. Abundance of reference genes encoding beta-actin (ACTB), glyceraldehyde 3-phosphate dehydrogenase (GAPDH), hypoxanthine-guanine phosphoribosyltransferase (HPRT), peptidylprolylisomerase A (PPIA) and TATA box-binding protein (TBP) as well as meat-quality associated genes (insulin-like growth factor 1 (IGF1), pyruvate dehydrogenase kinase isozyme 4 (PDK4), and peroxisome proliferator-activated receptor delta (PPARD) were investigated using qPCR. Transcript abundances of ACTB, GAPDH, HPRT, and PPIA were significantly different among all postmortem time points (p<0.05). Transcript levels of PDK4 and PPARD were significantly reduced in the 6 h samples (p<0.05). The findings suggest an adverse effect of a prolonged postmortem duration on reliability of transcript quantification in chicken skeletal muscle. For the best RNA quality, chicken skeletal muscle should be immediately collected after evisceration or within 20 min postmortem, and rapidly preserved by deep freezing.