• Bulletin of the Korean Chemical Society
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• v.34 no.1
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• pp.201-206
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• 2013

The second-order rate constants have been measured spectrophotometrically for the reactions of paraoxon 1 and parathion 2 with a series of alicyclic secondary amines, $OH^-$ and $HOO^-$ ions in $H_2O$ at $25.0{\pm}0.1^{\circ}C$. A linear Br${\o}$nsted-type plot with ${\beta}_{nuc}$ = 0.40 was obtained for the reactions of 1 with amines and $OH^-$. The reaction has been concluded to proceed through a concerted mechanism. $HOO^-$ deviates positively from the linear Br${\o}$nsted-type plot, implying that the ${\alpha}$-effect is operative. The magnitude of the ${\alpha}$-effect ($k_{HOO^-}/k_{OH^-}$) was found to be ca. 55 for the reaction of 1 and 290 for that of parathion 2, indicating that $HOO^-$ is highly effective in decomposition of the toxic phosphorus compounds although it is over 4 $pK_a$ units less basic than $OH^-$. Among the theories suggested as origins of the ${\alpha}$-effect (e.g., TS stabilization through an intramolecular Hbonding interaction, solvent effect, and polarizability effect), polarizability effect appears to be the most important factor for the ${\alpha}$-effect in this study, since the polarizable $HOO^-$ exhibits a larger ${\alpha}$-effect for the reaction of the more polarizable substrate 2.

• YAKHAK HOEJI
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• v.42 no.1
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• pp.82-88
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• 1998

The effect of hepatoprotective agents and bile acids on tumor necrosis factor-alpha, (TNF-${\alpha}$) production in murine and human macrophage cell line (RAW264.7 and U937) was inve stigated. The hepatoprotective agents including silymarin and its major component, silybin, significantly inhibited TNF-alpha production in a concentration dependent manner ($IC_50$ of silybin=67.7${\mu}g$/ml (140.3${\mu}g$M)). In differentiated U937 cells, especially, silybin showed more effective inbitory activity ($IC_50$=35.1${\mu}g$g/ml (72.7${\mu}g$M)). These results suggest that silymarin and silybin may inhibit TNF-alpha production in the process of hepatic diseases in human. However, biphenyldimethyl dicarboxylate (DDB) was not effective. In the case of bile acids, chenodeoxycholic acid (CDCA) showed a concentration dependent inhibitory effect on TNF-alpha production ($IC_50$ of CDCA= 71.5${\mu}g$g/ml (182.1${\mu}g$M)). In contrast, glycine or taurine conjugated form (G-CDCA or T-CDCA) restored to the control level or significantly increased TNF-${\alpha}$ production. And also ursodeoxycholic acid (UDCA) and its conjugated forms (G-UDCA and T-UDCA) showed a variety of patterns on TNF-${\alpha}$ production by changes of functional groups and concentration. These results also indicate that bile acids may regulate TNF-${\alpha}$ production in normal hepatic function or disease conditions.

• Archives of Pharmacal Research
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• v.9 no.4
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• pp.219-222
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• 1986

Dose-dependent increasesin blood glucose were produced by epinephrine and clonidine in fasted male mice. Isoproterenol was ineffective in increasing blood glucose at lower doses ($10^{-8}M$/kg-$10^{-7}M$/kg); with higher dose ($10^{-6}M$/kg) the glucose level was increased. The hyperglycemia induced by epinephrine was inhibited by yobimbine, prazosin and propranolol, indicating that the hyperglycemic effect of epinephrine is mediated by alpha-1, alpha-2 and beta adrenoceptor. When clonidine (10$^{-6}$ M/kg) was administered simultaneously with sioproterenol ($10^{-6}M$/kg), an enhenced hyperglycemic effect was observed. The increment produced by clonidine plus isoproterenol was higher than that by clonidine alone. These increment produced by clonidine plus isoproterenol was higher than that by clonidine alone. These results suggest that stimulation of alpha-2 adrenoceptor may be reponsible for the exertion of the hyperglycemic effect by beta agonists in fasted mice.

• Journal of Embryo Transfer
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• v.15 no.1
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• pp.77-83
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• 2000

The purpose of this study was to develop a breeding technique to increase Hanwoo of superior characteristics. In the present study, reproductive status of Hanwoo such as size of farm, breeding system and gestationi length was investigated. In addition, effect of low dose administration of prostaglandin F2$\alpha$(PGF2$\alpha$) on luteolysis was examined. The size of farm was classified by the total number of cows and the number of breeding stocks, respectively. The distribution of herd size of < 5, 6~10, 11~30, 31~50 and > heads was 31%, 15%, 39%, 4% and 11%, respectively. Furthermore, the distribution of breeding stock size of <5, 6~10, 11~30, 31~50 and > 50 heads was 36%, 28%, 31%, 3% and 3%, respectively. Average parity was 2.1 in breeding stock. In breeding pattern, artificial in semination(A.I), estrus synchronization-A.I and natural mating was 92.7%, 2.4% and 4.9% respectively. Gestational length of Hanwoo was ranged 253~316 days (average length : 285 days) after estrus( estrus=0). To induce luteolysis, PGF2$\alpha$ was injected into ovarian parenchyma by a modified ovarian injector. The effect of administration of 6mg PGF2$\alpha$ on luteolysis and estrus induction was betweer (P<0.01) when PGF2$\alpha$ was administered into ovarian parechyma than when administered intramuscluarly (71 vs. 91%). When PGF2$\alpha$ was injected into ovarian parenchyma, a decreased concentration to 3 mg did not significantly decreaed its luteolytic effect(92%). When AI was performed following PGF2$\alpha$ treatment, the intraovarian injection group yielded a higher pregnancy rate(69 vs. 88%) than the IM injection groups, regardless of the dosage. In conclusion these results suggest that increasing herd size and regular reproductive management are needed to improve reproductive efficiency in Hanwoo industry. Furthermore, intraovarian administration of PGF2$\alpha$ is effective way to induce luteolysis compared with intramuscular injection.

• The Korean Journal of Pharmacology
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• v.18 no.1
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• pp.11-16
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• 1982

This study was carried out in order to clarify whether the cardiovascular effect of prostaglandin(PG) $F_{2{\alpha}}$ might be centrally mediated. In unrestrained conscious rat, $PGF_{2{\alpha}}$ was administered into the lateral ventricle. The mechanism of action was also studied by observing the interaction with several adrenergic antagonists injected subcutaneously, Indomethacin was administered into lateral ventricle to investigate the role of endogenous $PGF_{2{\alpha}}$ on the central regulation of cardiovascular system. The results were as follows: 1) The intraventricular injection of $PGF_{2{\alpha}}$ produced an increase in blood pressure and heart rate. 2) The pretreatment with phenoxybenzamine (2 mg/g, s.c.) inhited pressor, but not heart rate responses to the intraventricular injection of $PGF_{2{\alpha}}$ $(2{\mu}g/kg)$. 3) The pretreatment with propranolol (1 mg/kg, s.c.) inhibited tachycardia, but not pressor responses to the intraventricular injection of $PGF_{2{\alpha}}(2{\mu}g/kg)$. 4) The intraventricular injection of indomethacin $(40{\mu}g/kg)$ could not induce significant changes in blood preesure and heart rate. 5) The result indicates that intraventricular injection of $PGF_{2{\alpha}}$ produces pressor and tachycardia responses in the unanesthetized rat, and it is mediated primarily by centrally increased sympathetic outflow. But the endogenous $PGF_{2{\alpha}}$ synthetized in the brain seems to play minor role in the direct regulation of cardiovascular system.

• Journal of Oriental Neuropsychiatry
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• v.12 no.1
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• pp.137-149
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• 2001

Cytokines are polypeptides which possess various biological properties affecting. host defense function and response to disease. Inflammatory cytokines, tumor necrosis $factor-{\alpha}$(TNF-${\alpha}$), interleukin(IL)-1 and IL-6 induce inflammation, fever, hypotension and pain when injected into animals or human subject. When glial cell cultures were prepared from neonatal mice or rats, astrocytes were reported to produce these inflammatory cytokines to viral infection, lipopolysaccharide(LPS), or cytokines. The purpose of this study was to investigate the regulatory effect of these cytokines secretion from primary cultures of rat astrocytes. Substance P(SP) can stimulate secretion of TNF-${\alpha}$ from astrocytes stimulated with LPS. Sesim-Tang significantly inhibited the TNF-${\alpha}$ secretion by astrocytes stimulated with SP and LPS. IL-1 has been shown to elevate TNF-${\alpha}$ secretion from LPS-stimulated astrocytes while having no effect on astrocytes in the absence of LPS. We therefore also investigated whether IL-1 mediated inhibition of TNF-${\alpha}$ secretion from primary astrocytes by Sesim-Tang. Treatment of Sesim-Tang to astrocytes stimulated with both LPS and SP decreased IL-1 secretion significantly. The secretion of TNF-${\alpha}$ by LPS and SP in astrocytes was progressively inhibited with increasing amount of IL-1 neutralizing antibody. Furthermore Sesim-Tang inhibited the IL-6 secretion by astrocytes stimulated with SP and LPS. The inhibitory effect of inflammatory cytokines by Sesim-Tang, observed in this study, might reflect an antiinflammatory activity and a reduction of various-type pains, fever etc. in the central nervous system.

• Journal of Ginseng Research
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• v.12 no.2
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• pp.128-134
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• 1988

The effect of the saponin fraction extracted from Panax ginseng C.A. Meyer on the antioxidant activity of $\alpha$-tocopherol was investigated in vitro as well as in vivo. Microsomal preparation of rat(Winter, 180-200g) liver was incubated in the mixture containing NADPH, $Fe^{3+}$, ATP, $\alpha$-tocopherol with and/or without ginseng saponin fraction for 30 minutes and the malondialdehyde formed was assayed and found that the saponin fraction stimulated the antioxidant activity of $\alpha$-tocopherol cooperatively. It was also realized that the cooperative stimulation of the antioxidant activity of $\alpha$-tocopherol was most eminent when the concentration of the saponin fraction was around $10^{-5}$% in the reaction mixture. Alcoholic suspension of $\alpha$-tocopherol with and f or without ginseng saponin fraction was administered orally to rats in which the lipid preoccupation was induced by ethanol administration and the lipid peroxide contents of the liver were assayed at certain periods of time after $\alpha$-tocopherol administration in this animal. From the previous work and present experimental results, it seemed that the saponin fraction accelerated the absorption of $\alpha$-tocopherol and therefore stimulated the antioxidant activity of $\alpha$-tocopherol more effectively in the animal body.

• Journal of the Korean Ceramic Society
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• v.24 no.5
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• pp.447-452
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• 1987

${\alpha}$-Al2O3 powder was produced at 1000$^{\circ}C$ by the boehmite sol-gel process with seeding 2 wt% ${\alpha}$-Al2O3. The processes and mechanisms of fornation of ${\alpha}$-Al2O3 was investigated using DTA/TG, XRD, TR spectroscopy and thermodynamic analysis. The specific surface area of the obtained ${\alpha}$-Al2O3 was 16.3㎡/g.

• KSBB Journal
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• v.25 no.1
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• pp.11-17
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• 2010

Here, we evaluated the effect of thrombin on the interleukin-6 production induced by tumor-necrosis-factor-$\alpha$ in endothelial cells. It is well known that tumor-necrosis-factor-$\alpha$ mediates inflammatory responses by activation of nuclear factor-kappa-B in endothelial cells. Here, we showed that lower concentration of thrombin decreased the production of interleukin-6 induced by tumor-necrosis-factor-$\alpha$ and this inhibitory effect of thrombin on interleukin-6 production was mediated by interacting with protease-activated-receptor-1. In addition, phosphoinositide-3-kinase was also involved the anti-inflammatory responses by lower concentration of thrombin in endothelial cells. These results suggested that lower concentration of thrombin mediated anti-inflammatory responses by interacting with protease-activated-receptor-1 on the cell membrane and phosphoinositide-3-kinase in the cell. These findings will provide the important evidence in the development of new medicine for the treatment of severe sepsis and inflammatory diseases and good clue for understanding unknown mechanisms by which thrombin showed the pro-inflammatory or anti-inflammatory activities in endothelial cells.

• Journal of Microbiology and Biotechnology
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• v.17 no.12
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• pp.1965-1969
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• 2007

Triamino ${\alpha}$-cyclodextrin (CD) was synthesized and the inclusion complex with Minoxidil (MXD) was prepared. ${\alpha}$-CD was azidated by modifying the 6-hydroxylmethyl CD rim with sodium azide. Then, mono-, di-, tri-, and tetra-azidocyclodextrins were separated by a flash column chromatography and reduced to the corresponding amines by hydrogenation with Pd/C. The substantivities of MXD included in either 2-hydroxypropyl ${\alpha}$-CD (HP ${\alpha}$-CD) or triamino ${\alpha}$-CD were evaluated in vitro using hairless mice skins. After applying the preparations onto the skin and rinsing it, the amount of the drug left on the skin was determined using high-performance liquid chromatography (HPLC). It was the highest when the drug was included in triamino ${\alpha}$-CD. The electrostatic interaction between the protonated amino CD and the negatively charged skin would be responsible for the relatively high substantivity. The in vivo hair growth promotion effect of each preparation was investigated, where the sample application onto the clipped backs of female mice (C57BL6) and the subsequent rinsing of the backs were done once a day for 30 days. Only MXD in triamino ${\alpha}$-CD had hair growth promotion effect, possibly due to the significant substantivity.