• Proceedings of the Ginseng society Conference
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• 1998.06a
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• pp.83-89
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• 1998

Ginseng total saponins (GTS) injected intracerebroventricularly (i.c.v.) at doses from 0.1-1 vs inhibited the i.c.v. injection stress-induced plasma corticosterone levels in mice. The inhibitory action of GTS was blocked by co-administered NG-nitro-L-arginine methyl ester (L-NAME; 1.5 us, i.c.v.), an. inhibitor of nitric oxide synthase (NOS). Of the ginsenosides Rbl, Rba, Rc, Rd, Re, Rf, Rgl,20(S)-Rg3, and 20(R)-Rg3 injected i.c.v. at doses from 0.01 to 0.3ug(or 1 uE),20(5)-Rg3 and Rc significantly inhibited the o.c.v. injection stress-induced Plasma corticosterone levels. The inhibitory actions of 20(S)-Rg3 and Rc were blocked by co-administered L-NAME (1.5 n, i.c.v.). These results suggest that G75, 20(S)-Rg3 and Rc may inhibit the i.c.v. injection stress-induced hypothalamo-pituitary-adrenal response by inducing NO production in the brain.

• Molecules and Cells
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• v.41 no.4
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• pp.290-300
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• 2018

Using an in vitro model of intestinal organoids derived from intestinal crypts, we examined effects of indole-3-carbinol (I3C), a phytochemical that has anticancer and aryl hydrocarbon receptor (AhR)-activating abilities and thus is sold as a dietary supplement, on the development of intestinal organoids and investigated the underlying mechanisms. I3C inhibited the in vitro development of mouse intestinal organoids. Addition of ${\alpha}$-naphthoflavone, an AhR antagonist or AhR siRNA transfection, suppressed I3C function, suggesting that I3C-mediated interference with organoid development is AhR-dependent. I3C increased the expression of Muc2 and lysozyme, lineage-specific genes for goblet cells and Paneth cells, respectively, but inhibits the expression of IAP, a marker gene for enterocytes. In the intestines of mice treated with I3C, the number of goblet cells was reduced, but the number of Paneth cells and the depth and length of crypts and villi were not changed. I3C increased the level of active nonphosphorylated ${\beta}$-catenin, but suppressed the Notch signal. As a result, expression of Hes1, a Notch target gene and a transcriptional repressor that plays a key role in enterocyte differentiation, was reduced, whereas expression of Math1, involved in the differentiation of secretory lineages, was increased. These results provide direct evidence for the role of AhR in the regulation of the development of intestinal stem cells and indicate that such regulation is likely mediated by regulation of Wnt and Notch signals.

• Bulletin of the Korean Chemical Society
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• v.24 no.8
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• pp.1141-1149
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• 2003

The structures and gas-phase ionization energies (ΔG°) of Meldrum's acid (I) and related cyclic (II-VI) and acyclic compounds (VII-IX) are investigated theoretically at the MP2/6-31+$G^*$, B3LYP/6-31+$G^*$, B3LYP/6- 311+$G^{**}$, B3LYP/6-311++G(3df,2p) and G3(+)(MP2) levels. Conformations of three neutral cyclic series vary gradually from boat (Meldrum's acid, I), to twisted chair (II) and to chair (III) as the methylene group is substituted for the ether oxygen successively. The preferred boat form of I can be ascribed to the two strong $n_O$ → σ* c-c antiperiplanar vicinal charge transfer interactions and electrostatic attraction between negatively charged C¹ and positively charged C⁴at the opposite end of the boat. All the deprotonated anionic forms have half-chair forms due to the two strong $n_C$ → π* c=0 vicinal charge transfer interactions. The dipole-dipole interaction theory cannot account for the higher acidity of Meldrum's acid (I) than dimedone (III). The origin of the anomalously high acidity of I is the strong increase in the vicinal charge transfer ($n_C$ → π* c=0) and 1,4-attrative electrostatic interactions (C¹↔C⁴) in the ionization (I → $I^-$ + $H^+$). In the acyclic series (VII-IX) the positively charged end atom, C⁴, is absent and the attractive electrostatic stabilization (C¹↔C⁴) is missing in the anionic form so that the acidities are much less than the corresponding cyclic series.

• Solar Energy
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• v.6 no.2
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• pp.3-14
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• 1986

It is desirable to collect the solar thermal energy at relatively high temperature in order to minimize the size of thermal storage system and to enlarge the scope of solar thermal energy utilization. In this study, to develop a solar collector that has both advantages of collecting solar thermal energy at high temperature and fixing conveniently the collector system for long term period, a cylindrical parabolique concentrating solar collector (M.C.P.C.S.C) was designed, which has several rows of parabolique reflectors and thin thickness such as the flat-plate solar collector, maintaining the optical form of concentrating solar collector. The thermal performance of the M.C.P.C.S.C. newly designed in this study was analysed theoretically and experimentally. The results are summarized as follows: 1) prediction equation for outlet temperature, $T_o$, of heat transfer fluid and for the thermal efficiency, ${\eta}$, of the collector were derived as; o $$T_o=[C+B1_n(\frac{I_c(t)}{pv^3})]T_i$$ o $${\eta}=\frac{A}{A_c}\dot{m}[(C-1)+B1_n(E{\cdot}di^6\frac{I_c(t)}{\dot{m}^3})]\frac{T_i}{I_c(t)}$$ 2) When the insolation on the tilted solar collector surface, $I_c$, was $900-950W/m^2$ and the heat transfer fluid was not circulated in tubular absorber, the maximum temperature on the absorber surface was $100-118^{\circ}C$, this result suggested that the heat transfer fluid could be heated up to $98-116^{\circ}C$. The maximum temperature on the absorber surface was decreased with the increase of the collector shape factor, $L_p/L_w$ 3) There was a good agreement between the experimental and theoretical value of solar collector efficiency, ${\eta}$, which was proportional to the collector shape factor, $L_p/L_w$ 4) It is desirable to continue the study on the relationship between the collector shape factor, $L_p/L_w$, and the thermal efficiency of solar collector.

• Journal of the korean academy of Pediatric Dentistry
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• v.34 no.3
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• pp.532-542
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• 2007

The purpose of study was to review the transition of dentition according to the evolution of man to know the background of the dental problems like hypodontia and malocclusion. Man is Kingdom Animalia, Phylum Chordata, Class Mammalia, Order Primates, Suborder Haplorrhini, Superfamily Hominoidea, Family Hominidae, Genus Homo, Species Sapiens by taxonomy. The first hominid was Australopithecus which appeared c. 4 millions of years ago and showed bipedalism and distinct dentition. Homos began with H. habilis who appeared c. 2.5 millions of years ago and made stone tools, and then H. erectus and H. neanderthalensis appeared and disappeared until H. sapiens came. The dental formula of primitive mammalians which was I3 C1 P4 M3 changed to I2 C1 P4 M3 of primitive primates, to I2 C1 P3 M3 of Haplorrhini, and to I2 C1 P2 M3 of hominoids. That of H. sapiens is changing to I2 C1 P2 M2.The box type dentition of hominoids changed to the omega type dentition of Australopithecus, and to the parabolic type of H. sapiens. The size of teeth decreased continually, especially the canine and sexual dimorphism. The dentition moved backward and downward to the cranial crown according to the increase of the brain and decrease of the jaws. It was suggested that the change of diet to the starchy foods, food processing, and the development of cooking reduced the necessity of mastication and caused the change of dentition. The future of H. sapiens who is quite a new species in the earth histroy and is now causing the mass extinction of other species is hard to see. It seems that hypodontia and malocclusion are related to the dentition change according to the evolution of man and is likely to increase.

• KSBB Journal
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• v.20 no.2 s.91
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• pp.106-111
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• 2005

The functional relationship between the number of mole of an i-fatty acid (Si) included in fish oil and the hydrolysis time(t) was expressed as a mathematical model, $S_i=-{\alpha_i}1n(t)+\beta_i$. The average errors of calculated values on the basis of the measured values were distributed in the range of less than $5\%$ for all the 15 fatty aids composing of fish oil. The equation of hydrolysis rate of each fatty acid was deduced as $v_i={\gamma_i}exp(\frac{S_i}{\alpha_i})$ from the above-mentioned $S_i=-{\alpha_i}ln(t)+{\beta_i}$. Therefore the hydrolysis yields of fatty acids were analyzed using the equation of $S_i\;Vs.\;t.$. The 15 fatty acids were categorized into 4groups from the view point of hydrolysis yield. The hydrolysis yields of the first group, including C14:0, C16:0, C16:1, C18:0, C18:1 (n-7) and 1l8:1 (n-9), were higher than $70\%$ at 48 hr of hydrolysis. Those of the second group, C20:1, C22:1, C18:3, C20:4 and C20:5, were distributed from $40\%,\;to\;60\%$, and third group were around $30\%$. The final group containing only C22:6 was very hard to be hydrolyzed and the yield was less than $20\%$ at the same time.

• Korean Journal of Microbiology
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• v.24 no.1
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• pp.18-23
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• 1986

A new type II restriction endonuclease, Bdi I, has been isolated from Brenibacterium divaricatum FERM 5948 by procedures of ammonium sulfate fractionation, DEAE-cellulose chromatography and heparin agarose chromatography. The purified Bdi I restriction endonudlease had the same cleavage patterns of Cla I whose recognition sequence is 5' ATCGAT 3'. From the result that ${\lambda}-Cla$ I DNA frahment could be cloned in pBR 322 digested with Bdi I, it has been proven that Bdi I cuts between T and C(5' AT/CGAT3') within the recognition sequence and produces 5'pCG cohesive end. The optimal temperature for the Bdi I restriction endonuclease activity was $37^{\circ}C$, and optimal salt (NaCl) concentration was 50-100 mM.

• Korean Journal of Food Science and Technology
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• v.53 no.3
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• pp.304-312
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• 2021

The present study aimed to develop new physiologically active ingredients from Angelica gigas. The polysaccharides purified from A. gigas, AGE-2c-I, showed potent anti-complementary activity in a dose-dependent manner. C₃ activation products were identified through crossed immuno-electrophoresis using anti-human C₃ antibodies and the anti-complementary activity of AGE-2c-I under Ca⁺⁺-free conditions suggests that AGE-2c-I may induce complementary activation via both alternative and classical pathways. In addition, AGE-2c-I augmented the production of various cytokines, such as interleukin (IL)-6, IL-10, IL-12, and tumor necrosis factor-α, by peritoneal macrophages. Furthermore, intravenous (i.v.) administration of AGE-2c-I dose-dependently enhanced natural killer cell cytotoxicity against YAC-1 lymphoma. In experimental lung metastasis, prophylactic i.v. administration of AGE-2c-I inhibited lung metastasis by 58% at 100 ㎍/mouse. From the above results, we suggest that AGE-2c-I purified from A. gigas has potent immune system-stimulating activities, and is a potentially promising food ingredient beneficial to human health.

• Journal of the Korean Chemical Society
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• v.15 no.6
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• pp.312-317
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• 1971

The interactions of aniline, o-toluidine, o-ethylaniline and o-chloroaniline with iodine in carbon tetrachloride solution have been examined through spectrophotometric measurements. The results indicate that both aniline and the o-substituted anilines examined form one-to-one complexes with I2in solution. The formation constants of the complexes measured at room temperature are 12.8, 9.31, 3.15 and 0.576 l $mole^{-1}$, respectively. Comparison of these results with previous experimental results indicates that the relative stabilities of the $I_2$-amine complexes decrease in the following order: $C_6H_5N(C_2H_5)_2 >C_6H_5N(CH_3)_2 >C_6H_5NH_2 >o-CH_3C_6H_4NH_2 >o-C_2H_5C_6H_4NH_2 >o-ClC_6H_4NH_2$. This may support the conclusion that the relative stabilities of these complexes are explained by the inductive effect and steric hindrance of the substituents.

• Electrical & Electronic Materials
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• v.9 no.9
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• pp.906-910
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• 1996

Ferroxplana N $i_{2}$Y(B $a_{2}$N $i_{2}$F $e_{12}$ $O_{22}$ ) magnetic particles, which is one of the hexagonal ferrite were synthesized by a coprecipitation method. The coprecipitates were prepared by adding aqueous solution of BaC $I_{2}$ - 2 $H_{2}$O, NiC $I_{2}$ - 6 $H_{2}$O and FeC $I_{3}$ - 6 $H_{2}$O(of which the mole ratio is $Ba^{+2}$ : N $i^{+2}$ : F $e^{3+}$= 1 : 1 : 6) to a mixture of NaOH and N $a_{2}$C $O_{3}$. The shape of Ferroxplana N $i_{2}$Y magnetic particles obtained at 1, 100(.deg. C) was hexagonal plate-like, average particle size and aspect ratio were 2(.mu.m) and 7, respectively.y.