• Journal of Microbiology and Biotechnology
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• v.22 no.8
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• pp.1170-1176
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• 2012

In this study, we aimed to evaluate the effect of ${\alpha}$-cyperone on S. aureus. We used a hemolysin test to examine the hemolytic activity in supernatants of S. aureus cultured with increasing concentrations of ${\alpha}$-cyperone. In addition, we evaluated the production of ${\alpha}$-hemolysin (Hla) by Western blotting. Real-time RT-PCR was performed to test the expression of hla (the gene encoding Hla) and agr (accessory gene regulator). Furthermore, we investigated the protective effect of ${\alpha}$-cyperone on Hla-induced injury of A549 lung cells by live/dead and cytotoxicity assays. We showed that in the presence of subinhibitory concentrations of ${\alpha}$-cyperone, Hla production was markedly inhibited. Moreover, ${\alpha}$-cyperone protected lung cells from Hla-induced injury. These findings indicate that ${\alpha}$-cyperone is a promising inhibitor of Hla production by S. aureus and protects lung cells from this bacterium. Thus, ${\alpha}$-cyperone may provide the basis for a new strategy to combat S. aureus pneumonia.

• Journal of Pharmacopuncture
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• v.19 no.2
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• pp.163-166
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• 2016

Objectives: Quercetin is a flavonoid and an important dietary constituent of fruits and vegetables. In recent years, several pharmacological activities of quercetin, such as its neuroprotective activity and, more specifically, its anti-convulsant effects in animal models of epilepsy, have been reported. This study evaluated the role of quercetin pretreatment on gene expression of ${\gamma}$-amino butyric acid type A ($GABA_A$) receptor beta subunits in kainic acid (KA)-induced seizures in mice. Methods: The animals were divided into four groups: one saline group, one group in which seizures were induced by using KA (10 mg/kg) without quercetin pretreatment and two groups pretreated with quercetin (50 and 100 mg/kg) prior to seizures being induced by using KA. Next, the messenger ribonucleic acid (mRNA) levels of the $GABA_A$ receptor ${\beta}$ subunits in the hippocampus of each animal were assessed at 2 hours and 7 days after KA administration. Quantitative real-time polymerase chain reaction (RT-PCR) assay was used to detect mRNA content in hippocampal tissues. Results: Pretreatments with quercetin at doses of 50 and 100 mg/kg prevented significant increases in the mRNA levels of the ${\beta}_1$ and the ${\beta}_3$ subunits of the $GABA_A$ receptor at 2 hours after KA injection. Pretreatment with quercetin (100 mg/kg) significantly inhibited ${\beta}_1$ and ${\beta}_3$ gene expression in the hippocampus at 7 days after KA injection. But, this inhibitory effect of quercetin at 50 mg/kg on the mRNA levels of the ${\beta}_3$ subunit of the $GABA_A$ receptor was not observed at 7 days after KA administration. Conclusion: These results suggest that quercetin (100 mg/kg) modulates the expression of the $GABA_A$ receptor ${\beta}_1$ and ${\beta}_3$ subunits in the KA model of epilepsy, most likely to prevent compensatory responses. This may be related to the narrow therapeutic dose range for the anticonvulsant activities of quercetin.

• Korean Journal of Animal Reproduction
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• v.27 no.4
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• pp.325-331
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• 2003

This study was performed to test the cellulose digestibility using the transgenic pigs harboring cellulose degradation gene D (CelD). After delivered offsprings between normal pig and transgenic swine, DNA was isolated from piglets tail for PCR analysis. In first generation, five out of 65 piglets showed CelD positive. Unfortunately, four CelD-positive pigs were died during growing, but one survived pig was used as a transgenic founder to produce F$_1$ descendents. Among 3 F$_1$ transgenic pigs produced, one died and the remaining two pigs were used to test the fiber digest efficiency. An assorted feed was composite of 5％ fiber with other ingredients. The feed of 3 kg per day was provided to the pigs including transgenic founders and littermate controls. The manure quantity was measured daily for a month, and all manures were dried for three days to analysis nitrogen, phosphate and fiber concentrations. The fiber digestion efficiencies of the transgenic F$_1$ pigs showed approximately 10％ higher than those of control pigs. Fiber digestion was not greatly improved in transgenic pigs as it had been expected approximately 30％. Nitrogen concentration of transgenic pig's manure was slowly decreased compare to the control pigs. Because there were only two transgenic pigs tested, a large number of transgenic pigs may be necessary to obtain more reliable data. Breeding of animals to obtain sufficient transgenic pigs subjected for a further study is on progress. Taken together, this study demonstrated successful production of transgenic pigs with increase of cellulose digestibility in the porcine feed.

• Reproductive and Developmental Biology
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• v.31 no.4
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• pp.267-272
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• 2007

Human embryonic stem (ES) cells are derived from the inner cell mass of the preimplantation embryo and have the capacity to differentiate into various types of cells in the body. Hence, these cells may potentially be an indefinite source of cells for cell therapy in various degenerative diseases including neuronal disorders. For clinical applications of human ES cells, directed differentiation of these cells would be necessary. The objective of this study is to develop the culture condition for the expansion of neural precursor cells derived from human ES cells. Human ES cells were able to differentiate into neural precursor cells upon a stepwise culture condition. Neural precursor cells were propagated up to 5000-fold in cell numbers over 12-week period of culture and evaluated for their characteristics. Expressions of sox1 and pax6 transcripts were dramatically up-regulated along the differentiation stages by RT-PCR analysis. In contrast, expressions of oct4 and nanog transcripts were completely disappeared in neural precursor cells. Expressions of nestin, pax6 and sox1 were also confirmed in neural precursor cells by immunocytochemical analysis. Upon differentiation, the expanded neural precursor cells differentiated into neurons, astrocytes, and oligodendrocytes. In immunocytochemical analysis, expressions of type III ${\beta}$-tubulin and MAP2ab were observed Presence of astrocytes and oligodendrocytes were also confirmed by expressions of GFAP and O4, respectively. Results of this study demonstrate the feasibility of long-term expansion of human ES cell-derived neural precursor cells in vitro, which can be a potential source of the cells for the treatment of neurodegenerative disorders.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.1
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• pp.101-108
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• 1998

We investigated the effect of ${\alpha}-subunit$ of the stimulatory GTP-binding protein ($G{\alpha}_s$) gene mutation on the expression of the thyrotropin-releasing hormone (TRH) receptor (TRH-R) gene in GH3 cells and in growth hormone (GH)-secreting adenomas of acromegalic patients. In the presence of cyclohexicmide, forskolin and isobutylmethylxanthine, cholera toxin, and GH-releasing hormone (GHRH) decreased rat TRH-R (rTRH-R) gene expression by about 39%, 43.7%, and 46.7%, respectively. Transient expression of a vector expressing mutant-type $G{\alpha}_s$ decreased the rTRH-R gene expression by about 50% at 24 h of transfection, whereas a wild-type $G{\alpha}_s$ expression vector did not. The transcript of human TRH-R (hTRH-R) gene was detected in 6 of 8 (75%) tumors. Three of them (50%) showed the paradoxical GH response to TRH and the other three patients did not show the response. The relative expression of hTRH-R mRNA in the tumors from patients with the paradoxical response of GH to TRH did not differ from that in the tumors from patients without the paradoxical response. Direct PCR sequencing of $G{\alpha}_s$ gene disclosed a mutant allele and a normal allele only at codon 201 in 4 of 8 tumors. The paradoxical response to TRH was observed in 2 of 4 patients without the mutation, and 2 of 4 patients with the mutation. The hTRH-R gene expression of pituitaty adenomsa did not differ between the tumors without the mutation and those with mutation. The present study suggests that the expression of TRH-R gene is not likely to be a main determinant for the paradoxical response of GH to TRH, and that $G{\alpha}_s$ mutation may suppress the gene expression of TRH-R in GH-secreting adenoma. However, a certain predisposing factor(s) may play an important role in determining the expression of TRH-R.

• Journal of Embryo Transfer
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• v.31 no.4
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• pp.335-347
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• 2016

Multiple interferon tau (IFNT) genes exist in bovine. An antiluteolytic substance secreted by the bovine conceptus and primarily responsible for maternal recognition of pregnancy is bovine trophoblast protein 1 (bIFNT1), a new type I interferon tau (IFNT) genes. The objectives of this research were to investigate whether multiple, distinct gene encode bIFNT1 and other type I bIFNT gene in the bovine genome and to examine expression of bIFNT1 and other bIFNTc1 mRNAs during conceptus development. These transcrips could be regulated through caudal-related homeobox-2 (CDX2) and ETS2 and/or AP1 (JUN) expression, a transcription factor implicated in the control of cell differentiation in the trophectoderm. The presence of mRNAs encoded by bIFNT1 and type I bIFNTc1 genes were examined quantitatively via reverse transcription-polymerase chain reaction (RT-PCR) analysis of total cellular RNA (tcRNA) extracted from on day 17, 20 and 22 bovine conceptuses. The expression level of bIFNT1 was higher on day 17 transcripts were gradually weakly detectable on day 20 and 22. However, the other bIFNTc1 gene examined transcripts was highly expressed on day 20 and transcripts were weakly detectable on day 17 and 22 bovine conceptuses. Furthermore, human choriocarcinoma JEG3 was co-transfected with an -1kb-bIFNT1/c1-Luc constructs and several transcription factor expression plasmids. Compared to each -1kb-bIFNT1/c1-Luc increased when this constructs were co-transfected with, ETS2, AP1(JUN), CREBBP and/or CDX2. Also, bIFNTc1 gene was had very effect on activity by alone ETS2, and AP1 (JUN) expression factors in choriocarcinoma JEG3 cell. However, bIFNT1 gene expression of the upstream region was not identified. We demonstrated that the activities of bIFN genes are regulated by differential, tissue-specific and developmental competence during pregnancy.

• Clinical and Experimental Pediatrics
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• v.48 no.8
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• pp.877-880
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• 2005

Purpose : Glycogen storage disease type Ia(GSD Ia) is an autosomal recessive disorder caused by the deficiency of glucose-6-phosphatase(G6Pase). The aim of the study was to investigate the spectrum of G6Pase gene mutations and relationship between genotype and clinical findings in Korean patients with GSD Ia. Methods : Genomic DNA was extracted from peripheral leukocytes of 20 patients with GSD Ia. The five exons of G6Pase gene were amplified and PCR products were directly sequenced. The frequency of short stature, hypoglycemia, hypercholesterolemia, hyperuricemia, hypercalciuria, nephrocalcinosis and hepatic adenoma was compared between 727G>T homozygotes and 727G>T compound heterozygotes. Results : A total of 5 different mutations were identified. The most common mutation was the 727G>T with an allele frequency of 80%. All patients were either homozygous(12/20) or heterozygous(8/20) for the 727G>T mutation. G122D was found in 3 patients, P178A in 1, G222R in 2, and S339R in 2. There was no difference in the frequency of short stature, hypoglycemia, hypercholesterolemia, hyperuricemia, nephrocalcinosis, and hepatic adenoma between 727G>T homozygotes and heterozygotes. Conclusion : Diagnosis of GSD Ia can be based on clinical and biochemical abnormalities combined with mutation analysis instead of enzymatic diagnosis that requires liver biopsy. Homozygosity for the 727G>T does not seem to alter the disease phenotype as compared with the heterozygous state.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.12
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• pp.1689-1695
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• 2008

Leptin, the hormone product of the obese gene, is secreted predominately from white adipose tissue and regulates feed intake, energy metabolism and body composition. It has been considered a candidate gene for performance, carcass and meat quality traits in beef cattle. The objective of this study was to identify SNPs in the promoter region of the leptin gene and to evaluate the possible association of the SNP genotypes with carcass and meat quality traits in Korean cattle. We identified a total of 25 SNPs in the promoter region (1,208-3,049 bp upstream from the transcription start site) of the leptin gene, eleven (g.1508C>G, g.1540G>A, g.1545G>A, g.1551C>T, g.1746T>G, g.1798ins(G), g.1932del(T), g.1933del(T), g.1934del(T), g.1993C>T and g.2033C>T) of which have not been reported previously. Their sequences were deposited in GenBank database with accession number DQ202319. Genotyping of the SNPs located at positions g.2418C>G and g.2423G>A within the promoter region was performed by direct sequencing and PCR-SSCP method to investigate the effects of SNP genotypes on carcass and meat quality traits in Korean cattle. The SNP and SSCP genotypes from the two mutations of the leptin promoter were shown to be associated with the BF trait. The average BF value of animals with heterozygous SNP genotype was significantly greater than that of animals with the homozygous SNP genotypes for the g.2418C>G and g.2423G>A SNPs (p<0.05). Analysis of the combined genotype effect in both SNPs showed that animals with the AC SSCP genotype had higher BF value than animals with BB or AA SSCP genotypes (p<0.05). These results suggest that SNP of the leptin promoter region may be useful markers for selection of economic traits in Korean cattle.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.9
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• pp.1254-1262
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• 2014

Lymphoid enhancer binding factor 1 (LEF-1) is a member of the T-cell specific factor (TCF) family, which plays a key role in the development of breast endothelial cells. Moreover, LEF-1 gene has been identified as a candidate gene for teat number trait. In the present study, we detected two novel mutations (NC_010450.3:g. 99514A>G, 119846C>T) by DNA sequencing and polymerase chain reaction-restriction fragment length polymorphism in exon 4 and intron 9 of LEF-1 in Guanzhong Black, Hanjiang Black, Bamei and Large White pigs. Furthermore, we analyzed the association between the genetic variations with teat number trait in these breeds. The 99514A>G mutation showed an extremely significant statistical relevance between different genotypes and teat number trait in Guanzhong (p<0.001) and Large White (p = 0.002), and significant relevance in Hanjiang (p = 0.017); the 119846C>T mutation suggested significant association in Guanzhong Black pigs (p = 0.042) and Large White pigs (p = 0.003). The individuals with "AG" or "GG" genotype displayed more teat numbers than those with "AA"; the individuals with "TC" or "CC" genotype showed more teat numbers than those with "TT". Our findings suggested that the 99514A>G and 119846C>T mutations of LEF-1 affected porcine teat number trait and could be used in breeding strategies to accelerate porcine teat number trait improvement of indigenous pigs breeds through molecular marker assisted selection.

• Journal of Microbiology and Biotechnology
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• v.24 no.6
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• pp.748-755
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• 2014

In the genome annotation of Escherichia coli MG1655, the orf382 (1,149 bp) is designated as a gene encoding an alcohol dehydrogenase that may be Fe-dependent. In this study, the gene was amplified from the genome by PCR and overexpressed in Escherichia coli BL21(DE3). The recombinant $6{\times}$His-tag protein was then purified and characterized. In an enzymatic assay using different hydroxyl-containing substrates (n-butanol, $\small{L}$-threonine, ethanol, isopropanol, glucose, glycerol, $\small{L}$-serine, lactic acid, citric acid, methanol, or $\small{D}$-threonine), the enzyme showed the highest activity on $\small{L}$-threonine. Characterization of the mutant constructed using gene knockout of the orf382 also implied the function of the enzyme in the metabolism of $\small{L}$-threonine into glycine. Considering the presence of tested substrates in living E. coli cel ls and previous literature, we believed that the suitable nomenclature for the enzyme should be an $\small{L}$-threonine dehydrogenase (LTDH). When using $\small{L}$-threonine as the substrate, the enzyme exhibited the best catalytic performance at $39^{\circ}C$ and pH 9.8 with $NAD^+$ as the cofactor. The determination of the Km values towards $\small{L}$-threonine (Km = $11.29{\mu}M$), ethanol ($222.5{\mu}M$), and n-butanol ($8.02{\mu}M$) also confirmed the enzyme as an LTDH. Furthermore, the LTDH was shown to be an ion-containing protein based on inductively coupled plasma-atomic emission spectrometry with an isoelectronic point of pH 5.4. Moreover, a circular dichroism analysis revealed that the metal ion was structurally and enzymatically essential, as its deprivation remarkably changed the ${\alpha}$-helix percentage (from 12.6% to 6.3%).