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        검색결과 441

        181.
        2012.06 구독 인증기관·개인회원 무료
        The objective of the present study was to investigate the effects of different concentrations of sorbitol supplementation for in vitro maturation medium and in vitro culture medium, on porcine cumulus oocyte complexe(COC) maturation and subsequent developmental capacity after parthenogenetic activation. Porcine COC were cultured for 44 h(0~ 22 h termed MI stage and 22~44 h termed MII stage) in TCM199 without(— ) or with(+) sorbitol (20 μM, 100 μM, 200 μM), and the resultant metaphase II oocytes cultured in PZM-3 for 7 days following activation. Our results showed that supplementation with appropriate concentrations of sorbitol (20 μM) during full term maturation culture(MI+/MII+) significantly(p<0.05) improved blastocyst formation rates and total cell number. When the concentration of sorbitol were increased to 100 μM and 200 μM during maturation culture, the maturation rate of COC were significantly reduced compared with 20 μΜ or control groups. Also blastocyst formation rates significantly(p<0.05) reduced with increasing concentration of sorbitol(200 μM). Supplementation with sorbitol(20 μM, 50 μM, 100 μM) into PZM-3 for in vitro culture significantly(p<0.05) inhibited blastocyst formation compared with control group. However, the blastocyst formation rates start to rise again when 50 μ M sorbitol was used for the first 48 hours and then cultured in PZM-3 without sorbitol. There was no significant difference in cell number between control and sorbitol treated groups. When the activated oocytes were cultured in PZM-3 for 48h and then cultured in PZM-3 with sorbitol, interestingly, the blastocyst formation rate was similar to that of PZM-3 with sorbitol for in vitro culture and significantly lower than control group. These results suggest that addition of low concentrations of sorbitol(20 μM) during oocyte maturation is beneficial for subsequent blastocyst development and improved embryo quality. However, treatment with sorbitol supplementation during in vitro culture medium is negative effect to blastocyst formation.
        182.
        2012.06 구독 인증기관·개인회원 무료
        Epigenetic status of the genome of a donor nucleus has an important effect on the developmental potential of cloned embryos produced by somatic cell nuclear transfer (SCNT). In our previous study has results showed that the donor cells treated with 5-aza-2’- deoxyctidine (5-aza-dC, DNA methylation inhibitors) and Trichostatin A (TSA, histone deacetylase inhibitors) could improve the development of porcine nuclear transfer embryos in vitro. In this study we want to investigate why these two drugs treatment with the donor cell can improve the cloning efficiency, whether they can alter the epigenetic status of the genome of the donor nucleus. This study included 6 groups: control group, the donor cell (porcine fetal fibroblast cell) with no treatment; 2.5 nM 5-aza-dC group, the donor cells treated with 2.5 nM 5-aza-dC for 1h; 5-aza-dC group, the donor cells treated with 5 nM 5-aza-dC for 1h; TSA group, the donor cells treated with 50 nM TSA for 1h; 2.5 nM 5-aza-dC+TSA group, the donor cells treated with 2.5 nM 5-aza-dC for 1h and subsequently treated with 50 nM TSA for another 1h; 5-aza-dC+TSA group, the donor cells treated with 5 nM 5-aza-dC and 50 nM TSA together for 1h. The first experiment detected the DNA methylation status in the different groups. After treatment with these two drugs, the DNA methylation level of the donor cells decreased, however there is no significant difference among the groups. This result indicated that the donor cell treatment with 5-aza-dC and TSA can partially alter the DNA methylation status of the donor cells. The second experiment checked the histone acetylation level of the donor cells treated with these two drugs by western blot. TSA, 2.5 nM 5-aza-dC+TSA, 5 nM 5-aza-aC+TSA, these three groups can significantly improve the hisone acetylation level compared with control and 5-aza-dC groups, there is no significant difference among these three groups. The results of this study suggest that the donor cells treated with 5-aza-dC and TSA can partially decrease DNA methylation and can significantly improve the histone acetylation level of the donor cells, these alterations of the epigenetic modification maybe can improve the clonging efficiency.
        183.
        2012.06 구독 인증기관·개인회원 무료
        An understanding of oocyte gene expression is a necessary for the study of early female gamete development. Recently, oocyte has been used in many techniques such as somatic cell nuclear transfer, intracytoplasmic sperm injection and embryonic stem cell derivation. The purpose of this study was to investigate in the proteomes of pig oocytes and identification of differential proteins between using DIGE technique. In this experiment to overcome of limitation of 2D gel method like a low reproducibility and low sensitivity for proteome analysis of very small quantities, 2D fluorescence difference gel electrophoresis (DIGE), which enables co-detection of up to three samples on the same 2DE gels with CyDyes was used for analysis of oocyte proteins. Proteins within an isoelectric point (pI) range of 3 to 10 and a molecular weight (Mw) range of 20~100 kDa were primarily analyzed in DIGE with 2 replications of each sample. Approximately 1000 spots were detected in 2-D gel. Then, image analysis of DeCyder was performed to detect variations in protein spots between mature oocyte and parthenogenesis embryo. In the comparison of mature oocyte and parthenogenesis embryo, 11 spots were identified to be up-regulated proteins and 2 spots to be down-regulated proteins in parthenogenesis embryo, among which proteins were zona pellucida glycoprotein 4, transferrin receptor, apolipoprotein B, L-3-Hydroxyacyl Coa Dehydrogenase Revisited, cytochrome P450 2C33, similar to Monocarboxylate transporter 2, 2'-5' oligoadenylate synthetase 3, interferon alpha/ beta receptor-1, Chloride channel protein 6, pyruvate carboxylase as well as2'-5' oligoadenylate synthetase 3 using MALDI-TOF-MS. These results suggested that differential proteins were present between mature oocyte and parthenogenesis embryo.
        184.
        2012.06 구독 인증기관·개인회원 무료
        In all the studies of mammalian species, chromatin in the germinal vesicle (GV) is initially decondensed with the nucleolus not surrounded by heterochromatin (the NSN configurations). During oocyte growth, the GV chromatin condenses into perinucleolar rings (the SN configurations) or other corresponding configurations with or without the perinucleolar rings, depending on species. During oocyte maturation, the GV chromatin is synchronized in a less condensed state before germinal vesicle breakdown (GVBD) in species that has been minutely studied. As not all the species show the SN configuration and gene transcription always stops at the late stage of oocyte growth, it is suggested that a thorough condensation of GV chromatin is essential for transcriptional repression. Because the GV chromatin status is highly correlated with oocyte competence, oocytes must end the NSN configuration before they gain the full meiotic competence and they must take on the SN or corresponding configurations to stop gene transcription before they acquire the competence for early embryonic development. In this study, we firstly investigated whether the follicle size could determine chromatin configuration in porcine oocyte. For this experiment, follicles was divided into three groups (<1 mm follicle, 1~3 mm follicle and 3~6 follicle). Using DAPI staining, the GV nucleolus and chromatin of porcine oocytes was classified into SN, SN-NSN and NSN configurations. MⅠ and M Ⅱ of three groups's Mature oocytes by staining was confirmed the configuration of chromatin. The maturation rate and parthenogenetic development potential were significant different between the SN and NSN configurations oocytes. These results indicated that chromatin changes in GV oocytes affect the development potential of porcine embryos.
        185.
        2012.06 구독 인증기관·개인회원 무료
        Neural stem cells (NSCs) are self-renewing tripotent cell populations and have capacity of neuronal (neurons) and glial (astrocytes and oligodendrocytes) differentiation. Many researchers have reported that NSCs have therapeutic effects in neurological disease by transplantation. However, it is not easy to obtain NSCs in vitro. Recently, Yamanaka and colleagues showed that somatic cells could be reprogrammed into pluripotent state by enforcing reprogramming factors. Induced pluripotent stem (iPS) cells undergo unlimited self-renewal and have differentiation potential into various types of cells like embryonic stem cells. Direct differentiation into a specialized cell types from iPS cells hold considerable promise for regenerative medicine as well as basic research. Here, we induced differentiation of iPS cells into NSCs in vitro and in vivo, which were compared with embryonic stem (ES) cell-derived NSCs and brain derived NSCs. NSCs from ES and iPS cells were morphologically indistinguishable from brain derived NSCs and stained positive for NSCs markers Nestin and Sox2. ES cells derived NSCs were transcriptionally distinguishable from brain derived NSCs. However, global gene expression pattern were similar but distinct between iPS derived NSCs and brain derived NSCs. Moreover, iPS derived NSCs were spontaneously aggregated upon passaging, formed ES cell like colonies, and finally reactivated Oct4-GFP. The spontaneously reverted GFP-positive cells (iPS-NSC-iPS) expressed similar levels of pluripotency markers (Oct4,Nanog) to ES and iPS cells, and could form germ line chimera. One possible explanation for this phenomenon is that spontaneously re-reprogramming was associated with transgene re-activation when iPS cells were differentiated into NSCs. However, NSCs from dox-inducible iPScells could not be reprogrammed into pluripotent state without doxycycline. Taken together, iPS derived NSCs were morphologically and similar to brain derived NSCs, but differ in gene expression pattern and maintenance. * This work was supported by the Next Generation Bio-Green21 Program funded by the Rural Development Administration (Grant PJ008009).
        186.
        2012.06 구독 인증기관·개인회원 무료
        Live offspring is obtained from in vitro production of porcine embryos, but the procedure is still associated with great inefficiencies. In mammalian oocytes, acquisition of meiotic competence coincides with a decrease in general transcriptional activity at the end of the oocyte growth phase. In this study, we investigated the expression and sub-cellular localization of positive transcription elongation factor P-TEFb (CDK9/Cyclin T1), a RNA polymerase II CTD kinase during pig oocyte growth and early embryonic development. Localization and expression of components involved in mRNA and rRNA transcription were assessed by immunocytochemistry in growing and fully-grown oocytes. In addition, meiotic resumption, germinal vesicle breakdown, nuclear transcription and embryonic genome activation (EGA) were analyzed in oocytes and embryos cultured in presence of a potent CDK9 inhibitor, flavopiridol. Our analyses, demonstrated that CDK9 became co- localized partially with phosphorylated Pol II CTD and mRNA splicing complexes. Surprisingly, CDK9 was co-localized with Pol I-specific transcription factor, UBF, and gradually localized in nucleolar peripheries at the final steps of oocyte growth. Later, CDK9 became associated with nucleolar structures at 4-cell stage. Treatment with flavopiridol resulted in arrest in meiotic resumption, germinal vesicle breakdown as well as a decline in global transcription. Flavopiridol also inhibited embryo development beyond EGA. All together, these data suggest that CDK9 has a dual role in both Pol I- and Pol II-dependent transcription in pig oocyte growth and embryonic development.
        187.
        2012.05 구독 인증기관·개인회원 무료
        In arthropods, an immune challenge triggers a serine protease cascade that leads to the activation of prophenoloxidase (proPO)-activating factors (PPAFs), which are also called proPO-activating enzymes (PPAEs) or proteinases (PAPs). PPAFs are activated by cleavage between their clip and serine protease domains. Once activated, PPAFs convert proPO to phenoloxidase (PO), which then catalyzes the production of quinones to form melanin. In this study, we identified a Bombyx mori PPAF(BmPPAF) that involves in the pupal melanization. In the fat body, expression of BmPPAF was detected on day 1 to 3 of the pupal stage. RNA interference (RNAi)-mediated BmPPAF knock-down inhibited pupal melanization, resulting in the delay of pupal melanization. Based on these results, we concluded that BmPPAF is involved in the melanization of pupal stage in silkworm metamorphosis.
        188.
        2012.03 구독 인증기관 무료, 개인회원 유료
        Cytokines are known to function as regulatory molecules that can be produced by virtually every nucleated cell type in the body, including lymphocytes, monocytes/macrophages, epithelial cells, fibroblasts, and many others. Cytokines include lymphocyte-derived factors (lymphokines), monocyte-derived factors (monokines), hematopoietic factors (colony-stimulating factors), connective tissue/ growth factors, and chemotactic chemokines. Cytokines released in response to infection can affect tumor development in different ways. When exposed to infectious agents, cytokines are secreted by sentinel cells, such as macrophages and dendritic cells. These cytokines include interleukin 1 (IL-1) and tumor necrosis factor-α, as well as others, such as IL-6, IL-12, and IL-18. When released in sufficient quantities, these molecules can cause inflammation. Chronic inflammation is highly associated with tumor initiation, promotion, and progression. In this article, we review the roles and mechanisms of cytokines in tumor development.
        4,300원
        189.
        2011.12 구독 인증기관 무료, 개인회원 유료
        The objective of this study was to determine the effect of macrophages on growth of human colon cancer cells. The results showed that co-culture of colon cancer cells with macrophages inhibited the growth of colon cancer cells (HCT116 and SW620) depending on the number of macrophages, RAW 264.7 cells, and activated THP-1 cells accompanied by down regulation of pSTAT3 in cancer cells. We also found that expression and release of cancer cell growth inhibitory cytokines, IL-1 receptor antagonist (IL-1ra) and IL-10, was increased in macrophages. Blocking of the STAT3 pathway with specific inhibitor and siRNA of STAT3 abolished the growth of colon cancer cells and expression of IL-1ra and IL-10. In addition, neutralization of IL-1ra and IL-10 with antibodies resulted in reversal of macrophage-induced inhibition of cancer cell growth. These data showed that IL-1ra and IL-10 released from macrophages inhibit growth of colon cancer cells through inhibition of the STAT3 pathway.
        4,500원
        190.
        2011.10 구독 인증기관·개인회원 무료
        An understanding of oocyte gene expression is a necessary for the study of biological development. Recently, Oocyte has been used in many techniques such as somatic cell nuclear transfer (SCNT), intracytoplasmic sperm injection (ICSI) and embryonic stem cell derivation. However, the molecular mechanism underlying porcine oocyte is still unclear. In this study, we present the description of the porcine oocyte proteome. Proteins within the isoelectric point ranges of 3.0 to 10.0 were analyzed separately using 2‐dimensional electrophoresis (2‐DE). About 450 spots were detected in 2‐ D gel of oocytes, stained with Coomassie blue. Subsequent excision of 227 spots from gels and MALDI‐TOF MS analysis allowed the identification of 85 proteins. Our results indicated the composite profiles of proteins in the porcine oocyte. Tubulin beta chain and meiosis‐specific nuclear structural protein 1 antibody was used to confirm those antibody expression levels in immature, mature and parthenogenetic embryo. Western blot analysis showed that expressions of those proteins increased during mature and parthenogenetic embryo. These protein profiles will make available important guides for the study of oocyte function and assist in functional analysis of the proteins.
        191.
        2011.10 구독 인증기관·개인회원 무료
        In all the studies of mammalian species, chromatin in the germinal vesicle (GV) is initially decondensed with the nucleolus not surrounded by heterochromatin (the NSN configurations). During oocyte growth, the GV chromatin condenses into perinucleolar rings (the SN configurations) or other corresponding configurations with or without the perinucleolar rings, depending on species. During oocyte maturation, the GV chromatin is synchronized in a less condensed state before germinal vesicle breakdown (GVBD) in species that has been minutely studied. As not all the species show the SN configuration and gene transcription always stops at the late stage of oocyte growth, it is suggested that a thorough condensation of GV chromatin is essential for transcriptional repression. Because the GV chromatin status is highly correlated with oocyte competence, oocytes must end the NSN configuration before they gain the full meiotic competence and they must take on the SN/corresponding configurations and stop gene transcription before they acquire the competence for early embryonic development. In this study, we firstly investigated whether the layer of cumulus cells and size of oocytes could determine chromatin configurations in porcine oocytes. Using Hoechst3342 staining, the GV nucleolus and chromatin of porcine oocytes was classified into SN and NSN configurations. Next, we examined the changes in GV chromatin configurations during growth and maturation of porcine oocytes. In addition, the maturation and parthenogenetic development abilities in vitro were significant different between the SN and NSN configurations oocytes. These results indicated that chromatin changes in GV oocytes affect the development potential of parthenogenetic embryos.
        192.
        2011.10 구독 인증기관·개인회원 무료
        In vitro production of porcine embryos, including in vitro maturation of oocytes followed by in vitro fertilization and in vitro culture, may result in live offspring, but it is still associated with great inefficiencies. In mammalian oocytes, acquisition of meiotic competence coincides with a decrease in general transcriptional activity at the end of the oocyte growth phase. In this study, we investigated the expression and sub‐cellular localization of CDK9, a RNA polymerase II CTD kinase during pig oocyte growth. Localization and expression of components involved in mRNA and rRNA transcription were assessed by immunocytochemistry in growing and fully‐grown oocytes. In addition, meiotic resumption, germinal vesicle breakdown and nuclear transcription were analyzed in oocytes cultured in presence of a potent CDK9 inhibitor, flavopiridol. Our analyses, demonstrated that CDK9 became co‐localized partially with phosphorylated Pol II CTD and mRNA splicing complexes. Surprisingly, CDK9 was co‐localized with Pol Ispecific transcription factor, UBF, and gradually localized in nucleolar peripheries at the final steps of oocyte growth. Treatment with flavopiridol resulted in arrest in meiotic resumption, germinal vesicle breakdown as well as a decline in global transcription. All together, this data suggest that CDK9 has a dual role in both Pol I‐ and Pol II‐dependent transcription in pig oocyte growth.
        193.
        2011.10 구독 인증기관·개인회원 무료
        5‐aza‐2’‐deoxyctidine (5‐aza‐dC) is DNA methylation inhibitor and Trichostatin A (TSA) is histone deacytlase inhibitor, both of them can alter the level of the epigenetic modification of cells. The objective of this study was to investigate the effects of treatment with 5‐aza‐dC and TSA into fetal fibroblasts on the development of porcine nuclear transfer (NT) embryos. In this study, experiments were performed in order to modify epigenetic status in donor cells and evaluate developmental potential of NT embryos. 5‐ aza‐dC or TSA or combining treatment of TSA and 5‐aza‐dC was treated into growing donor cells for 1 h exposure and development of NT embryos was evaluated. Experiment was performed with 3 groups: control group (donor cells without treatment); TSA group (donor cell treated with 50 nM TSA for 1 h); TSA + 5‐aza‐dC group (donor cells were treated with 50 nM TSA and 5 nM 5‐aza‐dC for 1 h); TSA+1/2(5‐aza‐dC) group (donor cells were treated with 50 nM TSA for 1h and subsequently treated with 2.5 nM 5‐aza‐dC for another 1h). When donor cells were individually treated with 5 nM 5‐aza‐dC or 50 nM TSA for 1h, the blastocyst rate of NT embryos increased significantly compared with control group [18.8% vs 13.4% (5 nM 5‐aza‐dC group vs control group), and 26.2% vs 11.8% (50 nM TSA group vs control group), p<0.05]. However, the blastocyst rate in combining treatment group (50 nM TSA + 5 nM 5‐aza‐dC) did not increase compare with control group (12.3% vs 11.8%, p>0.05). When the donor cell were individually treated with 50nM TSA for 1 h firstly and then treated with 2.5 nM 5‐aza‐dC for another 1h, the blastocyst rate was significantly improved compared with control and TSA group (28% vs 10.2% and 23.7%, p<0.05). The present study suggested that donor cells treated with TSA or low concentration of TSA+5‐azadC in short time exposure may enhance the development of porcine NT embryo.
        194.
        2011.10 구독 인증기관·개인회원 무료
        X‐box binding protein‐1 (XBP‐1) is an important regulator of a subset of genes active during endoplasmic reticulum (ER) stress. In the present study, we analyzed XBP‐1 level and location to explore the effect of ER stress on oocyte maturation and developmental competency of porcine embryos in an in vitro culture system. First, we examined the localization of XBP‐1 at different meiotic stages of porcine oocytes and at early stages of parthenogenetic embryo development. Fluorescence staining showed that expression of functional XBP‐1 was weak in mature oocytes and at the one‐cell, two‐cell, and eight‐cell stages of embryos, but abundant at the GV oocyte, four‐cell, morula, and blastocyst stages. In addition, RT‐PCR revealed that both spliced XBP‐1 (XBP‐1s ) and unspliced XBP‐1 (XBP‐1u) were expressed at the GV oocyte, four‐cell, morula, and blastocyst stages. Tunicamycin (TM), an ER stress inducer, blocked porcine embryonic development at the four‐cell stage, exhibiting the effect on embryonic genome activation. Next, porcine embryos cultured in the presence of tauroursodeoxycholate (TUDCA), an ER stress inhibitor, were studied. Total cell numbers and the extent of the ICM increased (p<0.05), whereas the rate of nuclear apoptosis decreased (p<0.05). Moreover, expression of the anti‐apoptotic gene Bcl‐2 increased whereas expression of the pro‐apoptotic genes Bcl‐xl and p53 decreased. The results indicated that inhibition of ER stress enhanced porcine oocyte maturation and embryonic development by preventing ER stress‐mediated apoptosis in vitro.
        195.
        2011.09 구독 인증기관 무료, 개인회원 유료
        This study was undertaken to evaluate the relationship between in vitro maturation and plasminogen activators (PAs) activity on porcine cumulus-oocytes complexes (COCs) exposed to oxidative stress. When COCs were cultured in maturation medium with hydrogen peroxide (H2O2), the proportion of the germinal vesicle breakdown (GVBD) and oocytes maturation were decreased with addition of H2O2, and were significantly (p<0.05) lower in medium with 0.1 mM H2O2 than control group. Also, the rate of degenerated oocytes was increased in as H2O2 concentration increased. When COCs were cultured for 48 h, three plasminogen-dependent lytic bands were observed: tissue-type PA (tPA); urokinase-type PA (uPA); and tPA-PA inhibitor (tPA-PAI). PA activity was quantified using SDS-PAGE and zymography. When H2O2 concentration was increased, tPA and tPA-PAI activities also increased in porcine oocytes cultured for 48 h, but not uPA. In other experiment, embryos were divided into three groups and cultured in (1) control medium, (2) control medium with 1.0 mM H2O2 and (3) control medium with 1.0 mM H2O2 along with catalase in concentrations of 0.01, 0.1, and 1.0 mg/ml, respectively. H2O2 decreased the rate of GVBD and maturation in porcine COCs but catalase revealed protective activity against oxidative stress caused by H2O2. In this experiment, tPA and tPA-PAI activities were higher in media with 1.0 mM H2O2 alone. Increasing concentration of catalase decreased tPA and tPA-PAI activities in porcine oocytes. These results indicate that the exposure of porcine follicular oocytes to ROS inhibits oocytes maturation to metaphase-II stage and increase the oocytes degeneration. Also, we speculated that increased ROS level may trigger tPA and tPA-PAI activities in porcine oocytes matured in vitro.
        4,000원
        196.
        2011.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        농촌진흥청 원예특작과학원에서는 2003년에 황색 폼 폰 화형인 ‘Restone’에 자주색 폼폰 화형인 ‘Lollipop’을 교배하여 획득한 실생 집단으로부터 황색 적심 폼폰 화형의 겹꽃 ‘03B1-82’ 계통을 선발하였다. ‘03B1-82’ 계통은 2005년 겨울부터 2007년 3년에 걸쳐 1, 2차 특성검정을 통해 안정성, 균일성 및 흰녹병저항성 검정 및 절화수명에 대해 조사되었고, 2008년에는 우수선발 계통으로 ‘원교B1-142호’ 계통번호를 부여받아 3차 특 성검정을 실시하여 안정성, 균일성에 대한 연차별 재현 성 그리고 주년생산성(촉성, 억제재배), 생산자 및 소 비자 기호성을 평가 받았다. ‘원교B1-142호’는 2008년 에 직무육성품종심의회를 거쳐 ‘옐로우캔디’로 명명되 어졌다. 국화 ‘옐로우캔디’는 10월 하순에서 11월 상 순에 자연 개화하는 절화용 스프레이 추국이다. 황색의 적색화심을 지닌 폼폰화형의 겹꽃으로 초세 및 줄기가 강건하다. 특히 여름철 고온기에도 통상화가 많이 발생 하지 않으며, 촉성 및 억제재배 등 주년생산이 가능하 다. 꽃의 직경이 4.3 cm 내외, 꽃잎수는 소화당 180매 이상, 착화수는 본당 8화 내외의 중형화로 절화수명은 18일 정도이다. 재배상 유의점으로는 둥근모양의 폼폰 형이기 때문에 수확시 꽃이 서로 엉키면 꽃이 떨어지는 경우가 있으며, 여름 장마철 또는 겨울철 환기 부족시 흰녹병 발생을 주의하고 주기적인 방제가 필요하다.
        4,000원