• Journal of the Korean Chemical Society
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• v.34 no.5
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• pp.469-475
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• 1990

The reaction of 2,6-dichloroquinoxaline (13) with m-chloroperbenzoic acid gave 2,6-dichloroquinoxaline 4-oxide (14), whose reaction with pyrrolidine or indoline provided 2-substituted 6-chloroquinoxaline 4-oxides (15). The isoxazolo[2,3-a]quinoxalines (16) and pyrrolo[1,2-a]quinoxalines (17) were selectively synthesized from the 2-substituted 6-chloroquinoxaline 4-oxides (15) and dimethyl acetylenedicarboxylate. Moreover, the pyrrolo[1,2-a]quinoxalines (17) were found to be produced by the ring transformation of the isoxazolo[2,3-a]quinoxalines (16).

• Journal of Aquaculture
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• v.8 no.2
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• pp.77-83
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• 1995

The effects of six levels (0, 5, 10, 15, 20, and 25 ppm) of dietary $17\alpha-Methyltestosterone$ (MT) on sex reversal and growth of Oreochromis aureus (Steindachner) and O. niloticus (L.) were evaluated. Fifteen ppm MT produced $100\%$ male populations in both species. Both MT-treated and untreated O. niloticus grew significantly faster than their O. aureus counterparts (P<0.05).

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.17 no.4
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• pp.267-278
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• 2013

We consider zero range processes with density dependent jump rates g given by $g=g(n,k)=g_1(n)g_2(k/n)$ with $g_1(x)=x^{-\alpha}$ and $$g_2(x)=\{^{x^{-\alpha}\;if\;a&lt;x}_{Mx^{-\alpha}\;if\;x{\leq}a}$$. (0.1) In this case, with 1/2 < a < 1 and ${\alpha}$ > 0, we show that non-complete condensation occurs with maximum cluster size an. More precisely, for any ${\epsilon}$ > 0, there exists $M^*$ > 0 such that, for any 0 < M ${\leq}M^*$, the maximum cluster size is between (a - ${\epsilon}$)n and (a + ${\epsilon}$)n for large n. This provides a simple example of non-complete condensation under perturbation of rates which are deep in the range of perfect condensation (e.g. ${\alpha}$ >> 1) and supports the instability of the condensation transition.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.11
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• pp.6761-6767
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• 2013

The nuclear receptor, peroxisome proliferator-activated receptor gamma ($PPAR{\gamma}$), is expressed in various cancer cells including breast, prostate, colorectal and cervical examples. An endogenous ligand of $PPAR{\gamma}$, 15-deoxy-${\Delta}^{12,14}$ prostaglandin $J_2$ (PGJ2), is emerging as a potent anticancer agent but the exact mechanism has not been fully elucidated, especially in breast cancer. The present study compared the anticancer effects of PGJ2 on estrogen receptor alpha ($ER{\alpha}$)-positive (MCF-7) and $ER{\alpha}$-negative (MDA-MB-231) human breast cancer cells. Based on the reported signalling cross-talk between $ER{\alpha}$ and $ER{\alpha}$, the effect of the $ER{\alpha}$ ligand, $17{\beta}$-estradiol (E2) on the anticancer activities of PGJ2 in both types of cells was also explored. Here we report that PGJ2 inhibited proliferation of both MCF-7 and MDA-MB-231 cells by inducing apoptotic cell death with active involvement of mitochondria. The presence of E2 potentiated PGJ2-induced apoptosis in MCF-7, but not in MDA-MB-231 cells. The $ER{\alpha}$ antagonist, GW9662, failed to block PGJ2-induced activities but potentiated its effects in MCF-7 cells, instead. Interestingly, GW9662 also proved capable of inducing apoptotic cell death. It can be concluded that E2 enhances $ER{\alpha}$-independent anticancer effects of PGJ2 in the presence of its receptor.

• Archives of Pharmacal Research
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• v.17 no.5
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• pp.323-326
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• 1994

Three new sesquiterpene lactone glucosides named dentatins A, B and C were isolated from lxeris dentata and the structures were elucidated as $3{\betha}, {\;}8{\betha}-dihydroxy-(1{\alpha}, 5{\alpha})guainan-10(14)-ene-6{\alpha}, {;\}12-olide-3-O-{\betha}-D-giucopyuranoside{\;}(1), {\;}3{\betha}, {\;}8{\betha}-dihydroxy-(1{\alpha}, {\;}5{\alpha})-guaian-4(15), {\;}10(14)-diene-6{\alpha}, {\;}12-plide-3-O-{\betha}-D-glucopyranoside{\;}(3)$, respectively, on the basis of spectral evidence.

• Journal of the korean veterinary medical association
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• v.17 no.3
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• pp.32-35
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• 1981

These experiments were carried out to define the effects of prostaglandin $F _{2\alpha}(PGF _{2\alpha})$ on estrous cycle and fertility in Holstein cows. Five mg of $PGF _{2\alpha}$ dissolved in l.0ml physiologic saline was given int

• Korean Journal of Animal Reproduction
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• v.26 no.2
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• pp.183-192
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• 2002

The present studies were carried out to examine the effects of exogenous oxytocin(OT) on plasma, uterine and placenta of estradiol-17$\beta$, progesterone, prostaglandin F$_2$$_{\alpha}$ (PGF$_2$$_{\alpha}$), Prostaglandin E$_2$(PGE$_2$) and OT receptor concentrations in pregnant rats. Pregnant rats received an injection of exogenous OT on days 14, 16, 18, 20, 22 of pregnancy and day 1 of postpartum. Concentrations of plasma estradiol-17 $\beta$ after OT injection started to increase after day 18 and peaked on day 22 of pregnancy but decreased on day 1 of postpartum. Plasma progesterone concentrations declined gradually from day 18 of pregnancy and decreased more rapidly until postpartum 1 day. Concentrations of estradiol-17$\beta$in uterine tissues after OT injection were sharply increased from day 20 to 22 of pregnancy and progestrone concentrations were peaked on day 16 and decreased rapidly from day 16 to 20 and maintained the same level until day 1 of postpartum. Uterine concentrations of PGF$_2$$_{\alpha}$ and PGE$_2$increased gradually until day 20 and peaked on day 22 of pregnancy but showed a marked decrease on day 1 of postpartum. Concentrations of PGF$_2$$_{\alpha}$ in placental tissues increased rapidly from day 14 of pregnancy and decreased sharply on day 1 of postpartum. Concentrations of PGE$_2$increased gradually after day 14 and peaked on day 20 of pregnancy. The concentration of OT receptor in uterus was significantly elevated from day 20 and rose to maximum on day 22 of pregnancy. These findings show that OT suppress the concentration of progestrone and stimulate productions of estradiol-17 $\beta$, PGF$_2$$_{\alpha}$, PGE$_2$ and oxytocin receptor concentrations in pregnant rats.

• Development and Reproduction
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• v.14 no.2
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• pp.115-121
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• 2010

The in vitro effects of nonylphenol (NP) and 2,2',4,6,6'-pentachlorobiphenyl (PCB104) on ovarian steroidogenesis of the ribbed gunnel, Dictyosoma burgeri were investigated. Oocytes taken during maturation stage were incubated with 100 ng/$m{\ell}$ of NP and PCB104 in the presence of exogenous precursor, $[^3H]-17{\alpha}$-hydroxyprogesterone ($[^3H]-17{\alpha}OHP$). Steroids were extracted from the media and the isolated oocytes, and the extracts were separated and identified by thin layer chromatography. The identities of the major metabolites were testosterone (T) and estradiol-$17{\beta}$ (E2). NP treatment inhibited production of E2 metabolite in the oocytes of 1.2, 1.3 and 1.4 mm although NP inhibited production of T metabolite at the oocytes of 1.1, 1.3 and 1.4 mm. PCB104 treatment inhibited production of T metabolite in the oocytes of all groups and E2 metabolite in the oocytes of 1.2, 1.3 and 1.4 mm. In conclusion, these results suggested that NP and PCB104 had an inhibitory effects on conversion of $[^3H]-17{\alpha}OHP$ to T and E2 during the oocyte maturation process of ribbed gunnel.

• Journal of the Korean Applied Science and Technology
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• v.17 no.3
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• pp.174-177
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• 2000

The effect of a-sexithiophene(${\alpha}-6T$) layers on the light emitting diode (LED) were studied. The ${\alpha}-6T$ was used for a buffer layer in electroluminescent (EL) devices. Enhanced carrier (hole) injection and improved emission efficiency were observed. Carrier injection characteristics were investigated as a function of ${\alpha}-6T$ later thickness. The efficiency of the electroluminescence was proportional to the thickness of ${\alpha}-6T$ layer. The highest efficiency was observed 600A of ${\alpha}-6T$ later, which was about 1.5 times higher than that of device without ${\alpha}-6T$ later. The device with a-6T showed an operation voltage lowered by 2V. The ${\alpha}-6T$ layer can substitute hole blocking layer, and control charge injection properties.

• Clinical and Experimental Pediatrics
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• v.52 no.4
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• pp.476-480
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• 2009

Purpose : The purpose of this study was to investigate the polymorphisms of the TNF-alpha promotor gene, its susceptibility to Kawasaki disease (KD) and to assess whether the TNF-alpha promotor gene polymorphism was related the risk of coronary artery lesions (CALs). Methods : From January 2003 to January 2007, 51 children (30 boys and 21 girls) with KD and 48 children forming an age-matched control group were studied. DNA from the peripheral blood of all the children was sampled, and the DNA polymorphisms of the 5' flanking regions of the TNF-alpha promoter gene at position -308 [guanine (G) to adenine (A)] were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Then, the relationship between KD and the TNF-alpha promotor gene polymorphisms was evaluated. Results : The A allele frequency of the -308 site of the TNF-alpha promotor gene was 17.6% (9/51) for children with KD and 6.8% (3/48) for the control group children, but this result was not statistically significant. Twenty-four patients experienced CALs within 60 days after the onset of symptoms. KD children with TNF-alpha -308 A allele had lower frequencies of CALs (12.5% versus 22.2%, P>0.05). Conclusion : The DNA polymorphism of the -308 site TNF-alpha gene was not associated with susceptibility to KD and a risk of CALs. Multicenter, large-scale randomized controlled trials are needed for further study.