• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 2003.10a
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• pp.178-178
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• 2003

Cytochrome P-450 3A4 (CYP3A4) is major enzyme in human liver, the role of this Is detoxification and metabolizing more than 50% clinical drugs in use. Expression of CYP3A4 is transciptionally regulated by the Pregnenolone X receptor (PXR), of which human form is Steroid and Xenobiotics receptor (SXR). SXR is activated by wide range of endogenous and exogenous compounds, and then induces CYP3A4 gene expression. In the previous study, it has been known that proximal promoter (-864 to ＋64) does not response to chemical inducers such as pregnenolone 16a-carbonitrile (PCN), Rifampicin, Estrogen in terms of transcription of CYP 3A4 in cultured cells. Here, we developed luciferase reporter gene assay system to detect SXR-based CYP 3A4 transcriptional activity. We have used CYP3A4-Luc plasmid that contains proximal promoter of human CYP3A4 gene upstream of the luciferase gene. We did transient transfection of 3A4-luciferase gene and SXR. In the HepG2 cells transfected with CYP3A4-Luc, when rifampicin treatment was combined with histone deacetylase inhibitor (HDAC Inhibitor), such as Trichostatin A, Hc-toxin and IN 2001 of the luciferase activity was induced 10-20 fold over control.

• Animal cells and systems
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• v.4 no.1
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• pp.87-90
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• 2000

Essential hypertension is a multifactorial disease, and has been shown to be associated with insulin resistance. The relationship between the genetic variation of the insulin receptor (INSR) gene and essential hypertension In Korean population was investigated by the Nsi 1 restriction fragment length polymorphism (RFLP) pattern of this gene. The observed genotype frequencies of INSR gene were not deviated from those expected for the Hardy-Weinberg equilibrium (HWE), but a significant association was observed between essential hypertension and N1 allele of Nsi 1 RFLP at the INSR gene ($X^2$-test; P<0.05). Moreover, the frequency of N1 allele was significantly different between normotensives and essential hypertensives in subgroups that were not obese ($X^2$-test; P<0.05). These data suggest that the Nsil RFLP of INSR gene may be a useful genetic marker for essential hypertension in Korean population.

• Journal of Genetic Medicine
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• v.19 no.2
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• pp.115-119
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• 2022

The 46,XX testicular disorder of sex development (DSD) is a rare condition in which 46,XX individuals develop testicular differentiation and virilization. Translocation of the sex-determining region Y (SRY) onto the X chromosome is the main cause of 46,XX testicular DSD, whereas dysregulation between pro-testis and pro-ovarian genes can induce SRY-negative 46,XX testicular DSD. Nuclear receptor subfamily 5 group A member 1 (NR5A1), a nuclear receptor transcription factor, plays an essential role in gonadal development in XY and XX embryos. Herein, we report the first Korean case of SRY-negative 46,XX testicular DSD with a heterozygous NR5A1 p.Arg92Trp variant. The patient presented with a small penis, bifid scrotum, and bilateral undescended testes. Whole exome sequencing revealed a heterozygous missense variant (c.274C>T) of NR5A1. Our case highlights that NR5A1 gene variants need to be considered important causative factors of SRY-negative non-syndromic 46,XX testicular DSD.

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2002.11a
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• pp.100-105
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• 2002

• Proceedings of the Korean Society of Toxicology Conference
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• 2003.10b
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• pp.172-173
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• 2003

There are growing concerns about human health effects of dioxin and dioxin like compounds such as polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and polychlorinated biphenyls (PCBs). Earlier studies recognized that 2.3.7.8-tetrachloro dibenzo-p-dioxin (TCDD) and structually related dioxin like compounds invoke a number of common toxic responses that are mediated through a high-affinity cytosolic receptor protein, the AhR.(omitted)

• Journal of Mushroom
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• v.2 no.4
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• pp.169-174
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• 2004

A hot water extract(HWE-P4) was separated from the fruit bodies of PMO-P4, and its antitumor and immunomodulatory activities against sarcoma-180 in ICR mice were investigated. The internal transcribed spacer(ITS) regions from PMO-P4 were amplified using polymerase chain reaction(PCR) and sequenced. The results revealed that PMO-P4 was belong to the Phellinus baumii. When oral administration at the dose of 160mg/kg/day in the mice until the end of the experiment with 2 week's pre-feeding of the HWE-P4, the survival rate of the mice was 152% for 50days after the inoculation of sarcoma-180 and the suppression rate of the tumor growth was 35.3%(p<0.05) for 28 days after inoculation of sarcoma-180. The HWE-P4 increased 71.4% of the CD4/CD8 ratio and 5-fold of the expression of CD25(IL-2 receptor chain) compared with the control. From these results, the antitumor activity of HWE-P4 is exerted through its immunomodulating activity on the host's immune system.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.9
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• pp.1223-1226
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• 2004

Previously candidate gene approach revealed estrogen receptor (ESR) locus was associated with increased litter size. In this study, PvuII polymorphisms of ESR gene was detected by PCR-RFLP, and ESR locus was evaluated for its association with reproductive tracts components in the Large $White{\times}Meishan$ ($LW{\times}M$) F2 offspring. Ninety seven gilts with reproductive tracts components records and 136 offspring with performance traits records were genotyped and the results were used to estimate allele substitution effects. The results showed that two alleles (A and B) were identified, and 121 bp fragments were observed for the AA genotype and 65 bp and 56 bp fragments for the BB genotype; the length of uterine body (LUB) of BB gilts were significantly shorter than AA gilts', the additive effect was -1.762 cm; the uterine weight (UW) of AB gilts were significantly lighter than AA gilts' with the additive effect -18.058 g; no significant associations of ESR alleles with ovulation rate (OR), length of uterine horn (LUH), length of uterine cervix (LUC), weight of two ovaries (OW), volume of uterine lumen (VUL), length of oviduct (LO) were observed. BB genotypes gilts need significantly less days to 100 kg ($D_{100kg}$) than AA genotypes (p<0.01), the additive effect was per copy of B allele. Allele B is also favorable for average daily gain (ADG), with additive effect 0.015 kg/d (p<0.05). There was no difference between genotypes for backfat thickness at the 13th rib (SF13), loin meat height (ELMH), and loin meat percentage was estimated (ELMP), individual birth weight (IBW) and teat number (TN).

• Archives of Pharmacal Research
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• v.14 no.2
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• pp.181-187
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• 1991

The muscarinic antagonist 1-[benzilic 4, 4'-$[^3H]$ QUINUCLIDINYL BENZILATE $([^3H]$ QNB) bound to a single class of muscarinic receptors with high affinity in rabbit ileal membranes. The $K_D\;and\;B_{ max}$ values for $([^3H]$ QNB calculated from analysis of saturation isotherms were 52.5 pM AND 154 fmol/mg, respectively. Chlopheniramine (CHP), histamine $H_1$ blocker, increased $K_D$ vlue for $([^3H]$QNB without affecting the binding site concentrations and Hill coefficient. The $K_i$ value of CHP for inhibition of $([^3H]$QNB binding in ileal membranes was 1.44\mu{M}$ and the pseudo-Hill coefficient for CHP was close to unit. In the functional assay carbachol, muscarinic agonist, increased the contractile force of ileum with $ED_{50}$ value of $0.11\mu{M}$. CHP caused the rightward shift of the dose-response curve to carbachol. The $pA_2$ value of CHP determined from Schild analysis of carbacholinduced contraction was 5.77 and the slope was unity indicating competitive antagonism with carbachol. The dissociation constant $(K_i)$ of CHP obtained in competitive experiments with $([^3H]$ QNB was similar to the $K_A$ value (1.69 \mu{M)}$ of CHP as inhibitor of carbachol induced contraction in rabbit ileum. This result suggest that the binding of $H_i$ blocker. CHP, vs $([^3H]$QNB to muscarinic receptors in ileal membranes represents an interaction with a receptor of physiological relevance.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2001.11a
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• pp.112-112
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• 2001

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is an environmental toxin that activates the aryl hydrocarbon receptor (AhR) and disrupts multiple endocrine signaling pathways by enhancing ligand metabolism, altering hormone synthesis, down regulating receptor levels, and interfering with gene transcription. And TCDD-mediated gene transactivation via the AhR has been shown to be dependent upon estrogen receptor (ER) expression in human breast cancer cells. In the present study, we have examined the effect of natural estrogen, phytoestrognes and environmental estrogens on the regulation of CYP1A1 gene expression in MCF-7 human breast cancer cell line. that ER and AhR are co-expressed. pCYP1A1 -luc reporter gene was transiently transfected into MCF-7 cells. These cells were treated with various chemicals and then luciferase assay was carried out. 17be1a-estradiol significantly inhibited TCDD stimulated luciferase activity dose dependently and this inhibition was partially recovered by concomitant treatment of tamoxifen. 17beta-estradiol metabolites, 2-hydroxyestradiol and 16alpha-estriol resulted in less potent inhibitory effect than estradiol and synthetic estrogen, diethylstilbestrol (DES) showed no effect on CYP1A1 gene expression. This study demonstrated that estrogen down-regulated TCDD stimulated CYP1A1 expression via ER mediation. And we have found out that several flavonoids such as genistein, kaempferol, daidzein, naringenin, and alkylphenols such as nonylphenol, 4-octylphenol and resveratrol also inhibited TCDD induced CYP1A1 expression like estrogen.

• Journal of Life Science
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• v.14 no.2
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• pp.309-314
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• 2004

Cyclic AMP receptor protein (CRP) is involved in the transcriptional regulation of more than 100 genes in E. coli. CRP dimer is converted into active form via the sequential conformation change of cAMP binding pocket, hinge region and HTH DNA binding motif by binding of cAMP. The temperature gradient gel electrophoresis (TGGE) was applied to CRP protein to know whether it was an efficient technique to study the conformational transitions and the thermal stability. TGGE showed the unfolding process of wild-type and S83G CRP proteins with the temperature gradient set from 29 to 71$^{\circ}C$ on nondenaturing polyacrylamide gel. Melting temperature (Tm) was 57$\pm$1 and 55$\pm$1$^{\circ}C$ for wild-type and S83G CRP, respectively in acidic buffer[89.8 mM Glycine and 24 mM Boric acid (pH 5.8)].