• Korean Journal of Agricultural Science
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• v.34 no.1
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• pp.19-35
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• 2007

The present study was carried out to examine the effect of EGF and IGF-I in vitro maturation (IVM) of porcine oocytes and development of porcine IVM/IVF embryos. The results were summarized as follows : 1. The rates of nuclear maturation, penetrated oocytes, pronuclear formation, polyspermic oocytes and mean numbers of the penetrated sperm were not different in NCSU-23 maturation medium with 0, 1, 5 and 10 ng/ml EGF and IGF-I (P>0.05). 2. The rates of blastocyst formation at day 7 after in vitro fertilization in 0, 1, 5 and 10 ng/ml EGF groups were $11.2{\pm}1.5%$, $15.0{\pm}8.3%$, $16.8{\pm}2.8%$ and $21.4{\pm}2.0%$, also 0, 1, 5 and 10 ng/ml IGF-I groups were $11.2{\pm}1.5%$, $15.0{\pm}8.3%$, $16.8{\pm}2.8%$ and $21.4{\pm}2.0%$, respectively. In the total cells case, EGF groups were $22.8{\pm}3.7$, $25.7{\pm}5.5$, $26.0{\pm}4.2$ and $35.1{\pm}4.7$, also IGF-I groups were $21.5{\pm}3.7$, $25.2{\pm}2.8$, $26.2{\pm}2.9$ and $33.2{\pm}3.6$, respectively. Both 10 ng/ml EGF group and 10 ng/ml IGF-I group were significantly higher than those of other treatment groups (P<0.05). 3. The rates of blastocyst formation at day 7 in the NCSU23 culture medium of porcine IVF-produced embryos with 0, 1, 5, and 10 ng/ml EGF groups were $14.0{\pm}1.7%$, $16.2{\pm}1.4%$, $16.9{\pm}1.2%$ and $23.1{\pm}1.6%$, also 0, 1, 5, 10 ng/ml IGF-I groups were $13.6{\pm}1.7$, $15.7{\pm}4.5$, $16.0{\pm}0.2$ and $25.0{\pm}0.8$, respectively. And in the total cells case, EGF grups were $21.8{\pm}2.9$, $25.2{\pm}2.8$, $39.7{\pm}2.7$ and $46.2{\pm}3.6$, also IGF-I groups were $20.7{\pm}2.9$, $26.2{\pm}2.9$, $24.6{\pm}2.4$ and $46.1{\pm}3.5$, respectively. Both 10 ng/ml EGF group and 10 ng/ml IGF-I group were significantly higher than those of any other treatment groups (P<0.05). In conclusion, these results suggested that the addition of 10 ng/ml EGF and IGF-I were effective on the blastocyst formation and total cells of blastocysts.

• Korean Journal of Animal Reproduction
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• v.24 no.4
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• pp.395-406
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• 2000

The present study was conducted to examine the developmental capacity of mouse oocytes within prenatal follicles cultured various concentrations of FSH and LH and the expression of cytochrome P450 cholesterol side-chain cleavage enzyme (P450scc) and cytochrome P450 17 $\alpha$ -hydroxylase (P450)$_{17{\alpha}}$ mRNA, as luteinization and atretic marker, in these culture conditions. In addition, we investigated the concentrations of progesterone and testosterone in culture medium. The developmental potential up to blastocyst of the oocytes grown in vitro was higher in the FSH alone (30.2%) and 10 $m\ell$U/$m\ell$ LH and 100 $m\ell$U/$m\ell$ FSH treated (28.0%) groups than in the 100 $m\ell$U/$m\ell$ LH and 100 $m\ell$U/$m\ell$ FSH treated group (22.0%). And the mean numbers of cell per blastocyst was higher in the FSH alone (50.9$\pm$26.1) and 10 $m\ell$U/$m\ell$ LH and 100 $m\ell$U/$m\ell$ FSH treated (51.0$\pm$21.1) groups when compared to the 100 $m\ell$U/$m\ell$ LH and 100 $m\ell$U/$m\ell$ FSH treated group (45.2$\pm$15.1). The expressions of P450scc and P450$_{17{\alpha}}$ mRNA in the oocyte -cumulus complexes were increased with increasing of LH concentration, and also the secretions of progesterone and testosterone were increased. Especially, in the 100 $m\ell$U/$m\ell$ LH and 100 $m\ell$U/$m\ell$ FSH treated group, the expression of P450scc and P450$_{17{\alpha}}$ were significantly increased, and the secretion of progesterone and testosterone were significantly increased. Therefore, these data show that gonadotrophins are essential for the in vitro culture of preantral follicles, but that increasing of LH concentration is reduced the developmental capacity of oocytes. The cause of these findings may be due to increasing of progesterone and testosterone secretion by the enhance of P450scc and P450$_{17{\alpha}}$ mRNA expressions, as markers of luteinization and atresia. Conclusively, this study suggest that supplementation of 100 $m\ell$U/$m\ell$ FSH or 10 $m\ell$U/$m\ell$ LH and 100 $m\ell$U/$m\ell$ FSH may be optimal condition for the culture of mouse pre antral follicles.

• Archives of Pharmacal Research
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• v.23 no.6
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• pp.605-612
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• 2000

Green tea polyphenols (GTP) have been demonstrated to suppress tumorigenesis in several chemical-induced animal carcinogenesis models, and predicted as promising chemopreventive agents in human. Recent studies of GTP extracts showed the involvement of mitogen-activated protein kinases (MAPKs) in the regulation of Phase II enzymes gene expression and induction of apoptosis. In the current work we compared the biological actions of five green tea catechins: (1) induction of ARE reporter gene, (2) activation of MAP kinases, (3) cytotoxicity in human hepatoma HepG2-C8 cells, and (4) caspase activation in human cervical squamous carcinoma HeLa cells. For the induction of phase IIgene assay, (-)-epigallocatechin-3-gallate (EGCG) and (-)-epicatechin-3-gallate (ECG) potently induced antioxidant response element (ARE)-mediated luciferase activity, with induction observed at 25 $\mu\textrm{m}$with EGCG. The induction of ARE reporter gene appears to be structurally related to the 3-gallate group. Comparing the activation of MAPK by the five polyphenols, only EGCG showed potent activation of all three MAPKs (ERK, JNK and p38) in a dose- and time-dependent manner, whereas EGC activated ERK and p38. In the concentration range of 25 $\mu\textrm{m}$ to 1 mM, EGCG and ECG strongly suppressed HepG2-ARE-C8 cell-growth. To elucidate the mechanisms of green tea polyphenol-induced apoptosis, we measured the activation of an important cell death protein, caspase-3 induced by EGCG, and found that caspase-3 was activated in a dose- and time-dependent manner. Interestingly, the activation of caspase-3 was a relatively late event (peaked at 16 h), whereas activation of MAPKs was much earlier (peaked at 2 h). It is possible, that at low concentrations of EGCG, activation of MAPK leads to ARE-mediated gene expression including phase II detoxifying enzymes. Whereas at higher concentrations of EGCG, sustained activation of MAPKs such as JNK leads to apoptosis. These mechanisms are currently under investigation in our laboratory. As the most abundant catechin in GTP extract, we found that EGCG potently induced ARE-mediated gene expression, activated MAP kinase pathway, stimulated caspase-3 activity, and induced apoptosis. These mechanisms together with others, may contribute to the overall chemopreventive function of EGCG itself as well as the GTP.

• Korean Journal of Veterinary Service
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• v.30 no.4
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• pp.497-503
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• 2007

The humoral immune response of chicken vaccinated with fowl and pigeon pox virus vaccines was determined with the protective potentiality of the two vaccines in field condition of Bangladesh. Different aged Fayoumi chicks were subjected for the study. To assess the relationship with better immune response among experimental groups, the average percentage of 'take reaction' was examined and recorded to 97.77% in group A, 93.33% in group B and 100.0% in group C. The level of immune status induced by different vaccinated group was measured by passive hemagglutination (PHA) microplate test method. The mean PHA titer levels after primary vaccination were $33.06{\pm}14.13$ in group A, $32.0{\pm}14.81$ in group B, and $33.0{\pm}13.66$ in group C. Following booster vaccination, the mean PHA titer levels in prior of challenge were increased to $55.46{\pm}14.64$ in groups A and C, and $46.93{\pm}16.52$ in group B. The recorded PHA titer levels of each group at two weeks after challenge were significantly increased to $106.66{\pm}31.22$, $93.86{\pm}33.04$ and $110.93{\pm}29.29$, respectively. The PHA titer levels after vaccination and challenge were significantly increased compared to pre-vaccination titer levels (P<0.01). Although the PHA titer levels among three groups administrated different vaccine combinations in prior of challenge were significantly varied (P<0.01), it was observed that all of the vaccinated chicks were highly protected against challenge infection.

• Journal of Preventive Medicine and Public Health
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• v.36 no.4
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• pp.314-322
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• 2003

Objectives : In this study, the exposure status of the hazardous substances from incinerators, such as polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), were studied , and the relationship between the exposure of these hazardous substances and their heath effects on the workers and residents near municipal solid waste (MSW) incinerators and an industrial incinerator investigated. Methods : Between July 2001 and Jure 2002, 13 workers at two MSW incinerators, 16 residents from the area around the two MSW incinerators, 6 residents from the control area, and further 10 residents near an industrial incinerator, estimated to emit higher levels of hazardous substances, were interviewed. Information, including sociodemographic information, personal habits, and work history, detailed gynecologic and other medical history were collected through interviews. Blood samples were also collected from 45 subjects, and analyzed for PCDD/DFs, by high resolution gas chromatography -high resolution mass spectrometry, using the US EPA 1613 method. In addition to the questionnaire survey, urinary concentrations of 8-hydroxydeoxyguanosine (8-OH-dG) and malondialdehyde (MDA) were measured as oxidative injury biomarkers. The urinary concentrations of 8-OH-dG were determined by in vitro ELISA, and the MDA by HPLC, using u adduct with thiobarbituric acid. Results : The PCDD/DFs concentrations in the residents near the industrial incinerator were higher than those in the controls, workers and residents near the MSW incinerators. The average TEQ (Toxic Equivalencies) concentrations of the PCDD/DFs in residents near the industrial incinerator were 53.4pg I-TEQs/g lipid. The estimated daily intakes were within the tolerable daily intake range (1-4 pg I-TEQ/Kg bw/day) suggested by WHO (1997) in only 30% to the people near the industrial incinerator. Animal studies have already shown that even a low body border of PCDD/DFs, such as 10 ng TEQ/kg bw, can cause oxidative damage in laboratory animals. Our study also showed that the same body burden of PCDD/DFs can cause oxidative damage to humans. Conclusions : The exposures to PCDD/DFs and the oxidative stress of residents near the industrial incinerator, were higher than those in the controls, workers and residents near the MSW incinerators. Proper protection strategies against these hazardous chemicals are needed. Because a lower body burden of PCDD/Fs, such as 10ng TEQ/kg bw, can cause oxidative damage, the tolerable daily intake range should be restrictedly limited to 1pg I-TEQ/kg bw/day.

• Journal of Food Hygiene and Safety
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• v.22 no.3
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• pp.218-222
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• 2007

Di(2-ethylhexyl) phthalate (DEHP) and di-n-butyl phthalate (DBP) were screened for estrogenic activity using a recombinant yeast screening system consisted with estrogen receptors and ${\beta}-galactosidase$ as reporter gene. The chemicals showed estrogenic activity in ranges of $1{\times}10^{-10}\;to\;1{\times}10^{-7}M(DEHP)\;and\;of\;1{\times}10^{-9}M\;to\;1{\times}10^{-6}M(DBP)$ respectively. $17{\beta}-estradiol$, as a positive control of, showed maximal activity at $1{\times}10^{-9}M$. The concentration of half-maximal estrogenic activity was $1{\times}10^{-9}M$ for both chemicals. However, the concentration of maximal estrogenic activity was $1{\times}10^{-7}M$ for DEHP and $1{\times}10^{-8}M$ M for DBP. These results suggested that DBP was higher in relative potencies and more sensitive than DEHP. In conclusion, DEHP and DBP were both estrogenic, even though DBP was more reactive to estrogen receptor.

• Journal of Aquaculture
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• v.9 no.3
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• pp.205-213
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• 1996

Experiments were carried out to investigate the effect of GnRH-analogue (GnRH-a) on the induction of ovulation in catfish, S. asotus. Fully matured female catfish ($250\~600\;g$) received a single intraperitoneal injection of GnRH-a ($50\~200\;{\mu}g/kg{\cdot}body$ weight) showed the successful induction of ovulation. More than $86\%$ of treated females were ovulated after injection of GnRH-a ($90\;{\mu}g/kg$) at $25{\pm}1^{\circ}C$. The majority of spawning took place within 22 to 25 hours after the injection. The gonadosomatic index (GSI) and pseudo-GSI in the group treated with $120\;{\mu}g/kg$ GnRH-a were $23-30\%$ and $18-21\%$, respectively. Average fertilization and hatching rates were $94\%\;and\;81\%$, respectively. Electron microscopically, gonadotrophs of maturing female catfish were characterized by the presence of numerous small, electron-dense granules of approximately $150\~300$ nm in diameter and a few larger, less electron-dense granules of approximately $800\~1000$ nm in size in their cytoplasm. Gonadotrophs of GnRH-a treated catfish showed that their was a distinct decrease in number of small and large granules. The rough endoplasmic reticulum was composed of numerous cisternae conspicuosly dilated to various degrees.

• Journal of Food Hygiene and Safety
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• v.21 no.3
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• pp.171-180
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• 2006

Peroxisome proliferatorr-activated receptor-gamma $(PPAR{\gamma})$ must form a heterodimer with the retinoid-X receptor (RXR) to bind DNA, and its transcriptional activity is thought to be maximized by ligands specific for either receptor. Activated $(PPAR{\gamma})$ and $(PPAR{\gamma})$ ligands may influence tumor growth through regulation of the tumor suppressor PTEN. Our aim in this study was to determine whether co-stimulation with the $(PPAR{\gamma})$ ligand, ciglitazone, and RXR ligand can synergistically upregulate PTEN in human acute promyelocytic leukemia (APL) cells and consequently potentate the inhibition of cell growth and cell cycle progression of these cells. Human leukemia cell line, HL-60 cells were exposed to all-trans-retinol and ciglutazone. The PTEN expression was measured as the level of PTEN mRNA expression by RT-PCR and as the level of PTEN expression by western blot analysis. Cell cycle analysis was carried out by a propidium iodide (PI) staining method and analyzed with a FACScan. The $(PPAR{\gamma})$ ligand, ciglitazone, and the RXR ligand, retinoic acid, upregulated PTEN expression by HL-60 cells in time- and dose-dependent manners, respectively. This was significantly enhanced by a combination of both ciglitazone and retinoic acid. Moreover, these compounds synergistically induced arrests of both cell growth and the $G_l$ phase of the cell cycle. Thus, the activation of the $(PPAR{\gamma})$:RXR heterodimer may represent a regulatory pathway for human leukemia cells and there may be important roles for $(PPAR{\gamma})$ and RXR ligands in prophylactic and therapeutic approaches fur controlling leukemia through the upregulation of PTEN.

• Journal of Food Hygiene and Safety
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• v.21 no.3
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• pp.181-188
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• 2006

Tumor necrosis factor-alpha $(TNF-{\alpha})$ plays a variety of biological functions such as apoptosis, inflammation and immunity. PTEN also has various cellular function including cell growth, proliferation, migration and differentiation. Thus, possible relationships between two molecules are suggested. $(TNF-{\alpha})$has been known to downregulate PTEN via nuclear factor-kappa $B(NF-{\kappa}B)$ pathway in the human colon cell line, HT-29. However, here we show the opposite finding that $(TNF-{\alpha})$ upregulates PTEN via activation of $NF-{\kappa}B$ in HL-60 cells. $TNF-{\alpha}$ increased PTEN expression at HL-60 cells in a time- and dose-dependent manner, but the response was abolished by disruption of $NF-{\kappa}B$ with p65 anisense oligonucleotide or pyrrolidine dithiocarbamate (PDTC). We found that $TNF-{\alpha}$ activated the $NF-{\kappa}B$ pathways, evidenced by the translocation of p65 to the nucleus in $TNF-{\alpha}-treated$ cells. We conclude that $TNF-{\alpha}$ induces upregulation of PTEN expression through $NF-{\kappa}B$ activation in HL-60 cells.

• Journal of Food Hygiene and Safety
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• v.29 no.3
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• pp.223-227
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• 2014

This study was investigated to determine the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) isolated from raw milk samples and to further study on the molecular characteristics of the MRSA isolates. Using Staphylococcus Medium 110, Staphylococcus spp. were isolated from raw milk samples and further identification was carried by Vitek2 system. Minimum inhibitory concentrations (MICs) of antibiotics were conducted by serial dilution method according to the Clinical Laboratory Standards Institute (CLSI) guideline. For the detection of resistance genes and molecular characterization, PCR reaction was performed by gene specific primers and followed by DNA sequencing. Of the 698 milk samples, 94 Staphylococcus aureus (S. aureus) were identified (94 S. aureus/286 Staphylococcus spp.). Of the 94 S. aureus, seven isolates have mecA, a methicillin resistant gene. mecA positive seven isolates were then characterized by staphylococcal cassette chromosome mec (SCCmec) typing, and Panton-Valentine Leukocidin (pvl) gene using PCR. All of mecA positive isolates were resistant to ampicillin and oxacillin, but sensitive to teicoplanin, vancomycin and ciprofloxacin. One of seven isolates was SCCmec type II and six isolates were type IV and all seven isolates were pvl gene negative.