검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 455

        201.
        2007.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study demonstrates that pork cholesterol levels are reduced in finishing swine fed β-cyclodextrin (βCD). The study subjects were 120 swine fed their respective chow diets containing 0, 5, 7, or 10% βCD for 35 consecutive days. Plasma total lipids, triglyceride and total cholesterol of the βCD- treated group were significantly lower than those of the control group (p<0.05). The levels of plasma lipid were significantly decreased by 63.22 mg, 73.98 mg, and 82.12 mg in the finishing swine group fed βCD at 5%, 7%, and 10% , respectively, compared to those in the control group (p<0.05). When 5, 7, and 10% βCD was administered to finishing swine, the triacylglyceride levels were decreased by 56.24 mg, 55.48 mg, and 60.02 mg, and total cholesterol concentration was reduced by 25.05 mg, 27.17 mg, and 30.19 mg, respectively, compared to those in the control group (p<0.05). Excretion of total steroid significantly (p<0.05) increased with increase of βCD supplementation. The cholesterol levels of swine back fat, belly, loin, and ham were significantly decreased with increase of βCD supplementation (p<0.05). The pork cholesterol was significantly (p<0.05) reduced by 15.31% in the βCD-treated group, compared to that of the control group. These results suggest that feeding βCD to finishing swine may produce novel functional pork with low cholesterol levels.
        4,000원
        207.
        2006.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Extensive oral mucosa loss from a variety of conditions is associated with significant functional morbidity and mortality. Although it is known that keratinocytes are a rich source of wound healing promoting factors such as transforming growth factor-β1(TGF-β1), it is not clear whether differentiated keratinocytes in a multi-layer form release this multi-functional growth factor. This study examined the hypothesis that keratinocytes in mono- and multi-layer forms expressed different levels of TGF-β1. When NHOK reached confluency in serum free medium(KBM), in test medium containing 1.2 mM Ca++ KBM NHOK were allowed to form multi-layers and differentiate. The purpose of this study were to investigate the mRNA level of TGF-β1, FGF-2, and TIMP-1 by RT-PCR analysis and also to evaluate the expression of TGF-β1 and involucrin in keratinocytes at different times of the onset of differentiation. The numbers and sizes of these nodules were increased as the process of keratinocyte differentiation proceed. Cultured NHOK in preconfluency under KBM medium expressed a significantly higher level of TGF-β1 relative to those grown in multi-layer forms, while the level of TGF-β1 mRNA gradually reduced to its lowest level at 7 days of growing cells in test medium. Cultured NHOK in preconfluency of KBM medium expressed a lower level of FGF-2 and TIMP-1 relative to those grown in multi-layer forms, while the level of FGF-2 and TIMP-1 mRNA showed the highest level at 3 days at gradually reduced to its lowest level at 7 days of growing cells in test medium. As a differentiation marker for keratinocytes at different time points, the highest level of involucrin mRNA expression was found at the later stage of cell differentiation. It suggested that the expression of TGF-β1 mRNA be consistent with the expression of FGF-2 and TIMP-1 mRNA in NHOK grown in high calcium medium during the terminal differentiation. But differentiated NHOK expressing higher involucrin mRNA could show constant espression of TGF-β1, FGF-2 and TIMP-1.
        4,000원
        208.
        2006.12 구독 인증기관 무료, 개인회원 유료
        Transforming growth factor-β (TGF-β) has been shown to have a positive effect on in vitro fertilization (IVF) and has been reported to stimulate meiosis at follicular level in variety of species. The study was designed to determine the expression patterns of TGF-β1, TGF-β receptors type Ⅰ, Ⅱ and Smads gene in bovine oocytes and embryos. TGF-β1 and their receptors were observed in the unfertilized oocytes. TGF-β1 and type Ⅱ receptor were not expressed at the blastocyst stage, however, only type I receptor was exclusively observed at the same stage. The blastocyst stage, in particular, showed high levels of mRNA expression patterns containing a TGF-β type Ⅰ receptor. The mRNA expression pattern of Smad 2 at all stages of embryonic development was similar in all respect with TGF-β1 type I receptor. On the contrary, Smad 3 and 4 were expressed with high and low level mRNA at the blastocyst stage. In conclusion, it is suggested that TGF-β signaling may be regarded as an important entity during the preimplantation embryo development.
        4,000원
        212.
        2006.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        β-catenin is a cytoplasmic protein that participates in the assembly of cell-cell adherens junctions by binding cadherins to the cytoskeleton. In addition, it is a key component of the Wnt signaling pathway. Activation of this pathway triggers the accumulation of β-catenin in the nucleus, where it activates the transcription of target genes. Abnarmal accumulation of β -catenin is characteristic of polyposis coli(APC) or Axin tumor suppressor proteins, which regulates β-catenin degradation, or activating mutations in β-catenin molecule itself. Here we show that overexpression of Sox4 down-regulates wild type β-catenin in HEK 293 cells. The inhibitory effect of Sox4 on wild type β-catenin is apparently mediated by the ubiquitin- proteasoem system and requires an active glycogen synthase kinase 3β(GSK3β). Mutations in the N-terminus of β -catenin(S33Y) which compromise its degradation by the proteasomes or inhibition of GSK3β activity rendered β-catenin resistant to down-regulation by Sox4. In light of recent evidence that Sox4 expression is activated in colon and other tumors with β-catenin dysregulation, our findings suggest that Sox4 is part of a feedback inhibitory pathway for Wnt signaling in normal cells. Moreover, the mutations in APC, Axin or β-catenin in cancer cells appear to render β-catenin resistant to the effects of Sox4 inhibition.
        4,000원
        213.
        2006.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Epithelium maintains homeostasis by the signaling balance of growth stimulation and inhibition. Recently, loss of growth inhibitory effects of transforming growth factor-β(TGF-β) on epithelial cells is regarded as a possible mechanism of cancer. Although the genomic mutation in type I and type Ⅱ receptors of TGF-β is considered one of important mechanism of these inactivation, there might be another inactivation mechanism because the mutation rate is relatively low and inhibitory effect is not associated with the mutation. The purpose of this study is evaluating controlling mechanism type Ⅱ receptor of TGF-β by detecting effects of TGF-β on growth inhibition and on expression of cell cycle regulatory protein p21CIP1. Eight cancer cell lines derived from oral squamous cell carcinoma(OSCC) were examined. There was no growth inhibition effects by TGF-β except YD-8 cells. YD-8 cells which showed growth inhibition expresses p21CIP1 by TGF-β whether refractory cell lines, YD-9, did not. All of the tumor cells express mRNA of type Ⅱ receptor by RT-PCR and northern blot analysis, especially on YD-8 and YD-17M. From these results, most of oral cancer cell lines might loose the growth inhibitory effects by TGF-β, and the growth inhibition on YD-8 cells was mediated by expression of p21CIP1.
        4,000원
        214.
        2006.06 구독 인증기관 무료, 개인회원 유료
        Nitric oxide(NO) is a labile, uncharged, reactive radical that functions as a sensitive mediator of intercellular communication in diverse tissues. It has been reported that NO is produced by osteoblast and these results may suggest that NO is integrally involved in the regulation of osteoclast formation and osteoclast resorption activity by osteoblastic cells. We examined the effect of cytokines on NO release by mouse bone marrow cell. We also examined the effects of cytokines and sodium nitroprusside(SNP) on the formation of osteoclast-like cell from mouse bone marrow cells in culture. Cytokines stimulated NO production of mouse bone marrow cells, and N-nitro-L-arginine methyl ester, a specific inhibitor of NO synthase, suppressed the cytokine-induced NO production. SNP showed dual action in the generation of osteoclasts. The addition of (30μM)SNP inhibited the formation of tartrate resistant acid phosphatase(TRAP)(+) multinucleated cell, whereas lower concentration(30μM) of SNP enhanced it. Although the precise action of NO remains to be elucidated in detail, the action of NO in osteoclast generation in our studies seems to be associated, at least in part, with bone metabolism and bone pathophysiology.
        4,000원
        215.
        2006.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Seasoning oil(SO-1) was manufactured from soybean oil, with β-carotene, oleoresin paprika and 3 kinds of flavors. Color of it's SO-1 was red. Total content of trans fatty acid of SO-1 was low level 0.84%, compare to the butter's and margarine's 1.35%, 28.31%, respectively. Total volatile components of SO-1 was 201,313.11ppm, was higher than soybean oil's, butter's, margarine's and SO-2's(removed 3 kinds of flavors from SO-1), it's value of 63.54ppm, 481.24ppm, 168.95ppm and 205.73ppm, respectively. And smoke point(SP) of SO-1 was higher than others. SP of SO-1, after 6 months later at room temperature, was 240, in contrast with soybean oil's 228. This SO-1, added β-carotene and flavor components, had a masking effect of burnt flavor. From these results, SO-1 can be replaced of butter or margarine as a substituted oil.
        4,000원
        218.
        2005.12 구독 인증기관 무료, 개인회원 유료
        Although it has been known that TGF-β1 acts as a crucial cofactor in osteoclast differentiation, its mode of action is still unclear. In the present study, we studied the effect of TGF-β1 on the differentiation of osteoclast depending on the developmental stages. Murine bone marrow cells were induced to differentiate into mature osteoclasts in the presence of receptor activator of NF-xβ ligand (RANKL) and macrophage colony stimulating factor (M-CSF). In the early stage of the differentiation TRAP(-) mononuclear precursor cells were obtained from nonadherent M-CSF dependent bone marrow cells, which further differentiated into mature osteoclasts. TGF-β1 stimulated osteoclast differentiation, which was stronger when cells were stimulated by TGF-β1 in the early stage than the later differentiation. TGF-β1 increased the expression of RANK and synergistically stimulated RANKL-induced activation of NF-xβ MAP kinase in TRAP(-) mononuclear precursor cells. These results suggest that activation of osteoclast differentiation by TGF-β1 may be ascribed to the both increased expression and activation of RANK in the osteoclast differentiation, especially in the early stage of differentiation.
        4,000원
        220.
        2005.12 구독 인증기관 무료, 개인회원 유료
        This study was conducted to test whether the transgenic cattle pass the transgene to their progeny through germ cells, and whether the transgene is expressed in the mammary gland of ransgenic cows. Two male ransgenic calves were born from IVF-derived embryos injected with bovine β-casein/human lactoferrin fusion gene and then grew up to be reproducible. Semen was collected from a transgenic bull after 18 mon of age and then frozen. Bovine oocytes matured in vitro were fertilized with spermatozoa of the transgenic bull and cultured in 50㎕ drops of CRlaa medium supplemented with 3 mg/mL BSA. After 48 h of culture, cleaved embryos were determined for the presence of transgenes by DNA polymerase chain reaction (PCR). Proportion of transgene positives among bovine embryos fertilized with sperm of the transgenic bull was 20.9% (28/134). One of transgenic bulls did not produce transgenic sperm. Out of 34 calves produced from recipient heifers inseminated with semen of the other bull, 3 (8.8%) were transgenic animals (2 females and 1 male). Thus, one transgenic bull showed a low transmission frequency below Mendelian levels in both the IVF-derived embryos and his progeny. It was demonstrated by Southern blot that copy numbers of the transgene in the transgenic progeny enhanced about 1.8 times as compared to those of the founder bull The results demonstrate that the transgenic bull carrying human lactoferrin gene could pass his transgene to the progeny through germ cells, although he is a germ-line mosaic.
        4,000원