• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.3
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• pp.232-241
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• 1984

A series of experiments were carried out to know the effects of pollen stage, cold shock temperature and duration, and media for callus and green plant induction in rice anther culture. The results indicated that: (a) uninucleate stage of pollen was the most suitable stage for effective callus induction, (b) cold shock temperature of 8$^{\circ}C$ and 12$^{\circ}C$ was appeared to be proper temperature for callus induction, (c) callus induction rate was increased in the eight to 12 days long cold storage, (d) the medium N6 was better than that of N6D for callus induction, (e) green plant induction was better in both 4$^{\circ}C$ and 8$^{\circ}C$ than that of 12$^{\circ}C$ cold shock, (f) green plant frequency was higher in eight to 12 days long cold storage and (g) green plant frequency was doubled in the MS medium when compared with N6 medium.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.6
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• pp.1100-1104
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• 1998

The preference test of cowpea mook(gel prepared with air-dried sediment of cowpea) indicated that the optimum concentration and heating temperature for mook-making were 8% at 95$^{\circ}C$ or 9% at 90$^{\circ}$and 95$^{\circ}C$ with continuous heating method(A), and 8% at 85$^{\circ}C$ or 7% at 9$0^{\circ}C$ with instantaneous heating method(B). Among the samples the mook made from 9% at 95$^{\circ}C$ with the method A was the most preferable. The degree of increase in hardness of mook prepared by the method B stored at 6$^{\circ}C$ for 8hr was much slower than that by the method A. the preference test of the mook stored at 6$^{\circ}C$ for 1 day revealed that the mook by the method A with 8%(95$^{\circ}C$) and by the method B with 7 and 8% (85$^{\circ}C$) were not significantly different.

• YAKHAK HOEJI
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• v.48 no.5
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• pp.272-277
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• 2004

The 2-amino-l-phenylpropanols 4∼7 were reacted with isothiocyanates to afford the 20 thioureido MAPP derivatives 8a∼11e, which were tested their cytotoxic activity by MTT assay. The cytotoxicity of alkylthioureido compounds were increased and decreased by alkyl chain length from $C_{8}$ to $C_{14}$ and of phenylthioureido compounds showed poor activity. The compounds (8b, 8c, 9b, 9c, l0b, 10c, 11b, 11c) with $C_{10}$ and $C_{12}$ alkyl chains gave stronger activity than reference compound B13. The $IC_{50}$/ of compound 8c was 1.05$\mu$M and 3 times stronger activity than B13. The stereochemistry of synthesized compounds affected very little to cytotoxic activity.

• IT SoC Magazine
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• s.14
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• pp.8-8
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• 2006

• IT SoC Magazine
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• s.13
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• pp.8-8
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• 2006

• Food Science and Biotechnology
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• v.15 no.5
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• pp.817-819
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• 2006

8-Quinolinol and other quinolinol derivatives were evaluated with regard to their growth-inhibitory effects against intestinal bacteria, using the paper disk-agar diffusion method. The observed growth responses varied according to the chemicals and dosages used, as well as the bacterial species tested. 8-Quinolinol showed a significant inhibitory effect against Clostridium difficile, C. perfringens, and Escherichia coli, at 5, 2, 1, and 0.5 mg/disk, and also exhibited a very strong inhibitory effect at 0.25 mg/disk. At low concentrations, 8-quinolinol had strong inhibitory effects against C. perfringens at 0.1 and 0.05 mg/disk; 8-quinolinol also manifested a moderate inhibitory effect against C. perfringens at 0.025 mg/disk. Furthermore, 8-quinolinol revealed moderate and weak growth inhibition against C. difficile and E. coli at concentrations of 0.1 and 0.05 mg/disk, respectively, but 2-quinolinol, 4-quinolinol, and 6-quinolinol evidenced no growth inhibition against B. bifidum, B. longum, C. difficile, C. perfringens, E. coli, or L. casei. The inhibitory effects of 8-quinolinol against C. difficile, C. perfringens, and E. coli lead to its consideration as a possible therapeutic modality for the treatment of diseases associated with harmful intestinal bacteria.

• IMMUNE NETWORK
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• v.1 no.1
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• pp.26-31
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• 2001

Background : Follicular dendritic cells (FDCs) play key roles during T cell-dependent humoral immune responses by allowing antigen-specific B cells to survive, proliferate, and differentiate within the FDC networks of secondary follicles, i.e., germinal centers (GC). Methods: A novel monoclonal antibody, 3C8, was generated by immunizing with an FDC line HK, in order to understand the molecular signals involved in the FDC-B cell interactions in the microenvironment of the GC. Results: The 3C8 antibody did not bind to mononuclear cells, including T cells, B cells, and monocytes. Murine L929 and human skin fibroblasts exhibited no or little reactivity to 3C8. However, 3C8 specifically recognized HK cells by flowcytometry. Furthermore, the antigen recognized by 3C8 was restricted to the GC of the human tonsil. Dendritic networks of the GC were intensely stained by 3C8, but cells outside the GC were not. Conclusion: Our results suggest that the antigen 3C8 may play some unique role on FDCs during the GC reactions.

• International Journal of Oral Biology
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• v.36 no.2
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• pp.83-89
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• 2011

Substantia gelatinosa (SG) neurons receive synaptic inputs from primary afferent $A{\delta}$- and C-fibers, where nociceptive information is integrated and modulated by numerous neurotransmitters or neuromodulators. A number of studies were dedicated to the molecular mechanism underlying the modulation of excitability or synaptic plasticity in SG neurons and revealed that second messengers, such as cAMP and cGMP, play an important role. Recently, cAMP and cGMP were shown to downregulate each other in heart muscle cells. However, involvement of the crosstalk between cAMP and cGMP in neurons is yet to be addressed. Therefore, we investigated whether interaction between cAMP and cGMP modulates synaptic plasticity in SG neurons using slice patchclamp recording from rats. Synaptic activity was measured by excitatory post-synaptic currents (EPSCs) elicited by stimulation onto dorsal root entry zone. Application of 1 mM of 8-bromoadenosine 3,5-cyclic monophosphate (8-Br-cAMP) or 8-bromoguanosine 3,5-cyclic monophosphate (8-Br-cGMP) for 15 minutes increased EPSCs, which were maintained for 30 minutes. However, simultaneous application of 8-BrcAMP and 8-Br-cGMP failed to increase EPSCs, which suggested antagonistic cross-talk between two second messengers. Application of 3-isobutyl-1-methylxanthine (IBMX) that prevents degradation of cAMP and cGMP by blocking phosphodiesterase (PDE) increased EPSCs. Co-application of cAMP/cGMP along with IBMX induced additional increase in EPSCs. These results suggest that second messengers, cAMP and cGMP, might contribute to development of chronic pain through the mutual regulation of the signal transduction.

• Bulletin of the Korean Chemical Society
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• v.10 no.6
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• pp.591-595
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• 1989

The$^{13}C$ NMR shifts of a series of para-substituted 9-aryl-tricyclo$[3.3.1.0^{2,8}]$non-9-yl and 8-aryl-tetracyclo$[3.2.1.0^{2,7}.0^{4,6}]$-oct-8-yl cations were measured in $FSO_3H/SO_2ClF \;at\; -90^{\circ}C\; or\; -70^{\circ}C$ in order to examine whether the ${\rho}^{c+}$ values can be used to explain the mechanism for the stabilization of the geometrically rigid cyclopropylcarbinyl cations. Plots of the ${\Delta}{\delta}^{c+}$ shifts against ${\sigma}^{c+}$ reveal excellent linear correlation. The tricyclononyl systems yield a ${\rho}^{c+}$ value of -4.95 with a correlation coefficient r = 0.9948. The tetracyclo-octanyl systems give a ${\rho}^{c+}$ value of -6.39 with r = 0.9943. A fair parallelism exists between the results of $^{19}F$ nmr studies and the change of ${\rho}^{c+}$ values in these cations. Accordingly, the present study established that the ${\rho}^{c+}$ value can be used as a mearsure of the geometric influence for the charge delocalization in cyclopropylcarbinyl cations.

• Journal of the Korean institute of surface engineering
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• v.31 no.2
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• pp.117-126
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• 1998

In this study, the residue remaining on the silicon wafer during the oxide overetching using $C_4F_8/H_2$ helicon were plasmas and effects of various cleaning and annealing methods on the removal of the remaining residue were investigated. The addition of 30%$H_2$ to the C4F8 plasma increased the C/F ratio and the thickness of the residue on the etched silicon surface. Most of the residuse on the etched surfaces colud be removed by the oxygen plasmsa cleaning followed by thermal annealing over $450^{\circ}C$. Hydrogen-coataining residue formed on the silicon by 70%$C_4F_8/30%H_2$ helicon plasmas was more easily removed than hydrogen-free residue formed residue formed by $C_4F_8$ helicon wear plasmas. However, damage remaining on the silicon surface overetched using 70%$C_4F_8/30%H_2$ helicon plasmas was intensive and the degree of reocvery duing the post-annealing was lower.