• Title/Summary/Keyword: Phase fraction

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Characterization and Modification of Milk Lipids (유지방의 특성과 변화)

  • Yeo, Yeong-Geun;Choe, Byeong-Guk;Im, A-Yeong;Kim, Hyo-Jeong;Kim, Su-Min;Kim, Dae-Gon
    • Journal of Dairy Science and Biotechnology
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    • v.16 no.2
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    • pp.119-136
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    • 1998
  • The lipids of milk provide energy and many essential nutrients for the newborn animal. They also have distinctive physical properties that affect the processing of dairy products. Milk fat globules mainly consist of neutral lipids like triacylglycerols, whereas the globule membranes contain the complex lipids mostly, Phospholipids are a small but important fraction of the milk lipids and are found mainly in the milk fat globule membrane and other membranous material in the skim-milk phase. The milk fats of ruminant animals are characterized by the presence of relatively high concentrations of short-chain fatty acids, especially butyric and hexanoic acids, which are rarely found in milks of non-ruminants. The fatty acids of milk lipids arise from de novo synthesis in the mammary gland and uptake from the circulating blood. The fatty acid compositions of milks are usually complex and distinctive, depending on the nature of the fatty acids synthesized de novo in the mammary gland and those received from the diet in each species. The content and composition of milks from different species vary widely; presumably, these are evolutionary adaptations to differing environments. The actual process by which these globules are formed is unkonwn, but there are indications that triglyceride-containing vesicles which bleb from endoplasmic reticulum may serve as nucleation sites for globules. Recent studies on milk have centred on the manipulation of milk lipids to increase specific fatty acids, i.e. 20-carbon omega-3 fatty acids (eicosapentaenoic acid 20:5n3, decosahexaenoic acid 22:6n3) from marine sources because the fatty acids are closely associated with a decreased risk of coronary heart disease.

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Biological Functions of N- and O-linked Oligosaccharides of Equine Chorionic Gonadotropin and Lutropin/Chorionicgonadotropin Receptor

  • Min, K. S.
    • Proceedings of the KSAR Conference
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    • 2000.10a
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    • pp.10-12
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    • 2000
  • Members of the glycoprotein family, which includes CG, LH, FSH and TSH, comprise two noncovalently linked $\alpha$- and $\beta$-subunits. Equine chorionic gonadotropin (eCG), known as PMSG, has a number of interesting and unique characteristics since it appears to be a single molecule that possesses both LH- and FSH-like activities in other species than the horse. This dual activity of eCG in heterologous species is of fundamental interest to the study of the structure-function relationships of gonadotropins and their receptors. CG and LH $\beta$ genes are different in primates. In horse, however, a single gene encodes both eCG and eLH $\beta$-subunits. The subunit mRNA levels seem to be independently regulated and their imbalance may account for differences in the quantities of $\alpha$ - and $\beta$ -subunits in the placenta and pituitary. The dual activities of eCG could be separated by removal of the N-linked oligosaccharide on the $\alpha$-subunit Asn 56 or CTP-associated O-linked oligosaccharides. The tethered-eCG was. efficiently secreted and showed similar LH-like activity to the dimeric eCG. Interestingly, the FSH-like activity of the tethered-eCG was increased markedly in comparison with the native and wild type eCG. These results also suggest that this molecular can implay particular models of FSH-like activity not LH-like activity in the eCG/indicate that the constructs of tethered molecule will be useful in the study of mutants that affect subunit association and/or secretion. A single-chain analog can also be constructed to include additional hormone-specific bioactive generating potentially efficacious compounds that have only FSH-like activity. The LH/CG receptor (LH/CGR), a membrane glycoprotein that is present on testicular Leydig cells and ovarian theca, granulosa, luteal, and interstitial cells, plays a pivotal role in the regulation of gonadal development and function in males as well as in nonpregnant and pregnant females. The LH/CGR is a member of the family of G protein-coupled receptors and its structure is predicted to consist of a large extracellular domain connected to a bundle of seven membrane-spanning a-helices. The LH/CGR phosphorylation can be induced with a phorbol ester, but not with a calcium ionophore. The truncated form of LHR also was down-regulated normally in response to hCG stimulation. In contrast, the cell lines expressing LHR-t63I or LHR-628, the two phosphorylation-negative receptor mutant, showed a delay in the early phase of hCG-induced desensitization, a complete loss of PMA-induced desensitization, and an increase in the rate of hCG-induced receptor down-regulation. These results clearly show that residues 632-653 in the C-terminal tail of the LHR are involved in PMA-induced desensitization, hCG-induced desensitization, and hCG-induced down-regulation. Recently, constitutively activating mutations of the receptor have been identified that are associated with familial male-precocious puberty. Cells expressing LHR-D556Y bind hCG with normal affinity, exhibit a 25-fold increase in basal cAMP and respond to hCG with a normal increase in cAMP accumulation. This mutation enhances the internalization of the free and agonist-occupied receptors ~2- and ~17-fold, respectively. We conclude that the state of activation of the LHR can modulate its basal and/or agonist-stimulated internalization. Since the internalization of hCG is involved in the termination of hCG actions, we suggest that the lack of responsiveness detected in cells expressing LHR-L435R is due to the fast rate of internalization of the bound hCG. This statement is supported by the finding that hCG responsiveness is restored when the cells are lysed and signal transduction is measured in a subcellular fraction (membranes) that cannot internalize the bound hormone.

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Interleukin-2 production and alteration of T cell subsets in mice infected with Naegleria fowleri (Naegleria fowleri 감염 마우스에 있어서 interleukin-2 생성 및 T 림프구 아형변동)

  • Yu, Cheol-Ju;Sin, Ju-Ok;Im, Gyeong-Il
    • Parasites, Hosts and Diseases
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    • v.31 no.3
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    • pp.249-258
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    • 1993
  • Naegleria fowleri is the cause of primary amoebic meningoencephalitis in man, IL-2 levels after stimulation of T lymphocytes by PHA or N.fowleri lysates. the amounts of T lymphocyte subsets and the blastogenic responses of T lymphocytes in mice after Infected with pathogenic N. fowleri were studied comparing between two study groups, one $1{\;}{\times}{\;}10^4$ trophozoites inoculated mice and the other $1{\;}{\times}{\;}10^5$ trophozoites inoculated mice. All experimental samples were obtained on the day 7, 14 and 24 after inoculation. The mice inoculated with $1{\;}{\times}{\;}10^4$ trophozoites showed a 14.3% mortality rate, and 72.2% in the mice inoculated with $1{\;}{\times}{\;}10^5$ trophozoites. The IL-2 levels on day 14 of two experimental groups were significantly decreased as compared with the control group. Thy 1.2+T cells in the total spleen Iymphocytes of $1{\;}{\times}{\;}10^5$ trophozoites inoculated group on day 7 were significantly increased compared with the control group. There was no significant difference between $1{\;}{\times}{\;}10^4$ trophozoites inoculated group and the control group. $L3T4^{+}{\;}T$ cells and $Ly2^{+}$ T cells in the total spleen Iymphocytes of $1{\;}{\times}{\;}10^5$ trophozoites inoculated group on day 7 were sigrlificantly increased compared with the control group. The DNA S fraction of T cells in the spleen of $1{\;}{\times}{\;}10^5$ trophozoites inoculated group was significantly increased on day 7. The amount of S fractions of DNA were sequentially decreased on day 14 and 24 but they were also signiacantly increased compared with the control group. The results obtained in the experiments indicats that cell mediated immunity after N.fowleri infection acts on very important host's protection immunity around the 7th day after infection. IL-2 level was much suppressed on day 14 which resulted from the exhaustion of host immune response. It was observed that the level of IL-2 production ability and the amounts of T lymphocytes subsets and the blastogenic responses of T lymphocytes were not well correlated during the observation period.

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Cytotoxicity of COX-2 Inhibitor (Nimesulide) in Non-small Cell Lung Cancer Cell Line (비소세포폐암 세포주에서 COX-2억제제(Nimesulide)의 세포독성)

  • Park Chan Beom;Jeon Hyun Woo;Jin Ung;Cho Kyu Do;Kim Chi Kyung;Wang Young-Pil
    • Journal of Chest Surgery
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    • v.38 no.4 s.249
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    • pp.263-270
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    • 2005
  • In recent years, a combination of two demographic phenomena, an increased number of older people in the population and an increase in the incidence of lung cancer with age, has made it mandatory to develop therapeutic modalities with less toxicity for the treatment of inoperable elderly patients with lung cancer. Therefore, we investigated the correlation between COX-2 expression and cytotoxicity of Nimesulide, a specific COX-2 inhibitor. Material and Method: Immunohistochemical staining of COX-2 was performed. After exposure of Nimesulide, XTT analysis, FACS analysis and Hoechst staining were carried out. Result: COX-2 protein was expressed in non-treated A549 cells strongly, but not in H1299. Cytotoxicity of Nimesulide against A549 cell and H1299 cell were similar and $IC_{50}$ of Nimesulide in both cell lines were $70.9{\mu}M$ in A549 cell line and $56.5{\mu}M$ in H1299 cell line respectively. FACS analysis showed $G_0/G_1$ arrest in both cell lines and the S phase cell fraction was decreased. Morphologic assessment of apoptosis by Hoechst 33258 staining, many apoptotic cells were detected in both cell lines. Conclusion: Selective COX-2 inhibitor, Nimesulide, can inhibit the proliferation of non-small cell lung cancer cell lines in vitro. Inhibitory effect of Nimesulide are induction of apoptosis and $G_0/G_1$ arrest. There is no correlation between COX-2 expression and cytotoxicity of Nimesulide, a specific COX-2 inhibitor. Therefore, highly selective COX-2 inhibitors such as Nimesulide can be expected to lead to even greater efficacy of their use as adjuncts to various anticancer angents and radiation therapy for the treatment of high-risk patients.

Sorption of PAHs by Soil Humins and Effect of Soil Inorganic Matrixs (PAHs의 토양휴민과의 흡착특성 및 토양 무기물의 영향 해석)

  • Lim, Dong-Min;Lee, Seung-Sik;Shin, Hyun-Sang
    • Journal of Korean Society of Environmental Engineers
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    • v.28 no.12
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    • pp.1337-1346
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    • 2006
  • Soil humin is the insoluble fraction of humic materials and play an important roles in the irreversible sorption of hydrophobic organic contaminants onto soil particles. However, there have been limited knowledge about the sorption and chemical properties of humin due to the difficulties in its separation from the inorganic matrix(mainly clays and oxides). In this study, de-ashed soil humins($Hu_1-Hu_6$) were isolated from a soil residues(Crude Hu) after removing alkali-soluble organic fractions followed by consecutive dissolution of the mineral matrix with 2%-HF for 2 hr. The humin samples were characterized by elemental analysis and $^{13}C$ NMR spectroscopic method and their sorption-desorption behavior for 1-naphthol were investigated from aqueous solution. The results were compared one another and that with peat humin. $^{13}C$ NMR spectra features indicate that the soil humin molecules are mainly made up of aliphatic carbons(>80% in total carbon) including carbohydrate, methylene chain. Freundlich sorption parameter, n was increased from 0.538 to 0.697 and organic carbon-normalized sorption coefficient(log $K_{OC}$) values also increased from 2.43 to 2.74 as inorganic matrix of the soil humin removed by HF de-ashing. The results suggest that inorganic phase in humin plays an important, indirect role in 1-naphthol sorption and the effects on the sorption non-linearity and intensity are analyzed by comparison between the results of soil humin and peat humin. Sorption-desorption hysteresis were also observed in all the humin samples and hysteresis index(HI) at low solute concentration($C_e$=0.1 mg/L) are in order of Peat humin(2.67)>De-ashed humin(0.74)>Crude Hu(0.59).

American Culture at the Crossroad : Debates over NEA(National Endowments for the Arts) (미국 문화, 그 기로에 서서 - NEA(국립예술진흥기금)를 둘러싼 논쟁 중심으로)

  • Kim, Jin-A
    • The Journal of Art Theory & Practice
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    • no.4
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    • pp.33-56
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    • 2006
  • The cultural debates between conservatives and liberals at the end of the 1980s and in the early 1990s were termed as "culture wars." The "culture wars" involved a diverse range of controversial issues, such as the introduction of multicultural curricula in educational institutions, prayers in schools, whether to allow gays to serve openly in the military, and whether abortion should be permitted. The most heated debates of the "culture wars" regarding art raged over the NEA and the question of whether Andres Serrano's works should have been publicly funded, in addition to the exhibition "Robert Mapplethorpe: The Perfect Moment" which were charged as projecting "obscene" or "blasphemous" images. This paper examines the development of culture wars in art and focuses on several issues invoked by the NEA debates. However, it is not a detailed chronological investigation. Rather it pays attention to the several phases of the debates, analyzing and criticizing the clashes of the political and esthetical points of views between conservatives and liberals. How could NEA funding, a mere fraction of the federal budget, have become so critical for both sides(conservative and liberal), for politicians and artists' groups, and for academics and the general public? The art community was astounded by this chain of events; artists personally reviled, exhibitions withdrawn and under attack, the NEA budget threatened, all because of a few images. For conservative politicians, the NEA debate was not only a battle over the public funding of art, but a war over a larger social agenda, a war for "American values and cultures"based on the family, Christianity, the English language, and patriarchy. Conservative politicians argued the question was not one of "censorship" but of "sponsorship," since the NEA charter committed it to "helping museums better serve the citizens of the United States."Liberals and art communities argued that the attempt to restrict NEA funding violated the First Amendment rights of artists, namely "free speeches." "No matter how divided individuals are on matters of taste," Arthur C. Danto wrote, "freedom is in the interest of every citizen." The interesting phase is that both sides are actually borrowing one another's point of view when they are accompanied by art criticism. Kramer, representative of conservative art critic, objected the invasion of political contents or values in art, and struggled to keep art's own realm by promoting pure aesthetic values such as quality and beauty. But, when he talked about Mapplethorpe's works, he advocated political and ethical values. By contrast, art experts who argued for Mapplethorpe's works in the Cincinnati trial defended his work, ironically by ignoring its manifest sexual metaphor or content although they believed that the issues of AIDS and homosexuality in his work were to be freely expressed in the art form. They adopted a formalistic approach, for example, by comparing a child nude with putti, a traditional child-angel icon. For a while, NEA debates made art institutions, whether consciously or unconsciously, exert self-censorship, yet at the same time they were also producing positive aspects. To the majority of people, art was still regarded as belonging to the pure aesthetic realm away from political, economical, and social ones. These debates, however, were expanding the very perspective on the notion of what is art and of how art is produced, raising questions on art appreciation, representation, and power. The interesting fact remains: had the works not been swiped in NEA debates, could the Serrano's or Mapplethorpe's images gain the extent of power and acceptance that it has today?

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Postoperative Radiotherapy for Parotid Gland Malignancy (귀밑샘 악성 종양의 수술 후 방사선 치료)

  • Eom Keun-Yong;Wu Hong-Gyun;Kim Jae-Sung;Park Charn Il;Kim In-Ah;Kim Kwang Hyun;Lee Chae Seo
    • Radiation Oncology Journal
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    • v.23 no.3
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    • pp.131-136
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    • 2005
  • Purpose: The aim of this study was to evaluate the clinical results of postoperative radiotherapy for parotid gland malignancy, and determine prognostic factors for locoregional control and survival. Materials and Methods: Between 1980 and 2002, 130 patients with parotid malignancy were registered In the database of the Department of Radiation Oncology, Seoul National University Hospital. The subjects of this analysis were the 72 of these 130 patients who underwent postoperative Irradiation, There were 42 males and 30 females, with a median age of 46.5 years. The most common histological type was a mucoepidermoid carcinoma. There were 6, 23, 23 and 20 patients in Stages I, II, III and IV, respectively. The median dose to the tumor bed was 60 Gy, with a median fraction size of 1.8 Gy. Results: The overall 5 and 10 year survival rates were 85 and $76\%$, respectively, The five-year locoregional control rate was $85\%$, which reached a plateau phase after 6 years. Sex and histological type were found to be statistically significant for overall survival from a multivariate analysis. No other factors, Including age, facial nerve palsy and stage, were related to overall survival. For locoregional control, nodal involvement and positive resection margin were associated with poor local control. Histological type, tumor size, perineural invasion and type of surgery were not significant for locoregional control. Conclusion: A high survival rate of parotid gland malignancies, with surgery and postoperative radiotherapy, was confirmed. Sex and histological type were significant prognostic factors for overall survival. Nodal Involvement and a positive resection margin were associated with poor locoregional control.

Effect of the Paclitaxel and Radiation on the Large Bowel Mucosa of the Rat (횐쥐의 대장점막에 Paclitaxel(Taxol)과 방사선조사의 효과)

  • Lee Kyung-Ja
    • Radiation Oncology Journal
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    • v.17 no.1
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    • pp.57-64
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    • 1999
  • Purpose : Paclitaxel is a chemotherapeutic agent with a potent microtubule stabilizing activity that arrests mitosis at G2-M phase of cell cycle which is the most radiosensitive period. Therefore paclitaxel is considered as a cell cycle-specific radiosensitizer. This study investigates the effect of paclitaxel on the radiation response of the normal large bowel mucosa of the rat. Materials and Methods: The rats were divided into the three groups i.e., single intraperitoneal infusion of paclitaxel (10 mg/kg), a single fraction of irradiation (8 Gy, x-ray) to the whole abdomen, and a combination of irradiation (8 Gy, x-ray) given 24 hours after paclitaxel infusion. The histological changes as well as kinetics of mitotic arrest and apoptosis were evaluated on the large bowel mucosa at 6 hours, 1 day, 3 days and 5 days after treatment with paclitaxel alone, radiation alone and combination of paclitaxel and radiation. Results : The incidence of the mitotic arrest was not increased by paclitaxel infusion. The apoptosis appeared in 24 hours after paclitaxel infusion, and the histopathologic changes such as vesiculation, atypia and reduction of the goblet cell of the mucosa of the large bowel were demonstrated during the period from 6 hours to 3 days after, and returned to normal in 5 days after paclitaxel infusion. In irradiated group, the apoptosis was increased in 6 and 24 hours after irradiation, and the histopathologic changes of the mucosa were appeared in 24 hours and markedly increased in 3 days and returned to normal in 5 days. In combined group of irradiation and paclitaxel infusion, the apoptosis was appeared in 3 days and the histopathologic changes appeared during the period from 6 hours to 3 days after infusion. On the basis of the incidence of apoptosis and the degree of the histopathologic changes of the large bowel mucosa, there seemed to be additive effect by paclitaxel on radiation rather than sensitizing effect. Conclusions: The histopathological changes of large bowel mucosa in combined group compared to radiation alone group suggested an additive effect of paclitaxel on radiation response in the large bowel of rat.

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Effects of Level and Degradability of Dietary Protein on Ruminal Fermentation and Concentrations of Soluble Non-ammonia Nitrogen in Ruminal and Omasal Digesta of Hanwoo Steers

  • Oh, Young-Kyoon;Kim, Jeong-Hoon;Kim, Kyoung-Hoon;Choi, Chang-Won;Kang, Su-Won;Nam, In-Sik;Kim, Do-Hyung;Song, Man-Kang;Kim, Chang-Won;Park, Keun-Kyu
    • Asian-Australasian Journal of Animal Sciences
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    • v.21 no.3
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    • pp.392-403
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    • 2008
  • Four ruminally fistulated Hanwoo steers were used to determine the effects of level and degradability of dietary protein on ruminal fermentation, blood metabolites and concentration of soluble non-ammonia nitrogen (SNAN) in ruminal (RD) and omasal digesta (OD). Experiments were conducted in a $4{\times}4$ Latin square design with a $2{\times}2$ factorial arrangement of treatments. Factors were protein supplements with two ruminal crude protein (CP) degradabilities, corn gluten meal (CGM) that was low in degradability (rumen-degraded protein (RDP), 23.4% CP) or soybean meal (SBM) that was high in degradability (RDP, 62.1% CP), and two feeding levels of CP (12.2 or 15.9% dry matter). Ruminal fermentation rates and plasma metabolite concentrations were determined from the RD collected at 2-h intervals and from the blood taken by jugular puncture, respectively. The SNAN fractions (free amino acid, peptide and soluble protein) in RD and OD collected at 2-h intervals were assessed by ninhydrin assay. Mean ruminal ammonia concentrations were 40.5, 74.8, 103.4 and 127.0 mg/L for low CGM, high CGM, low SBM and high SBM, respectively, with statistically significant differences (p<0.01 for CP level and p<0.001 for CP degradability). Blood urea nitrogen concentrations were increased by high CP level (p<0.001) but unaffected by CP degradability. There was a significant (p<0.05) interaction between level and degradability of CP on blood albumin concentrations. Albumin was decreased to a greater extent by increasing degradability of low CP diets (0.26 g/dl) compared with high CP diets (0.02 g/dl). Concentrations of each SNAN fraction in RD (p<0.01) and OD (p<0.05) for high CP diets were higher than those for low CP diets, except for peptides but concentrations of the sum of peptide and free amino acid in RD and OD were significantly higher (p<0.05) for high CP diets than for low CP diets. Soybean meal diets increased free amino acid and peptide concentrations in both RD (p<0.01) and OD (p<0.05) compared to CGM diets. High level and greater degradability of CP increased (p<0.001) mean concentrations of total SNAN in RD and OD. These results suggest that RDP contents, increased by higher level and degradability of dietary protein, may increase release of free amino acids, peptides and soluble proteins in the rumen and omasum from ruminal degradation and solubilization of dietary proteins. Because SNAN in OD indicates the terminal product of ruminal metabolism, increasing CP level and degradability appears to increase the amount of intestine-available nitrogen in the liquid phase.

Time Course Variation of Liver 25-Bydroxyvitamin $D_3$ Content in Broiler Chicks Exposed to UVB Light with Different Dobe (상이한 선양의 자외선을 조사한 브로일러 병아리에 있어서 간장 25-Hydroxyvitamin $D_3$회량의 계치적 변화)

  • 장윤환;강훈석;여영수;김강수;조인호;배은경
    • Korean Journal of Poultry Science
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    • v.19 no.4
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    • pp.217-225
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    • 1992
  • This research was carried out to determine the 25-Hydroxyvitamin $D_3$[25(OH)$D_3$] content in liver of broiler Hubbard chicks fed vitamin VD-deficient diet for 31 days in a subdued light room and exposed to UVB light (maximum intensity at 297nm) with dose of 0.204 or 0.408 mJ/$\textrm{cm}^2$(30 or 60 min irradiation) . The lipid in liver collected at 0~138 hr after irradiation was extracted by chloroform-methanol(2:1, v /v) and 25(OH)$D_3$ fraction was separated by Sep-Pak silica cartridge. The 25(OH)$D_3$ concentration was measured by normal phase HPLC. The negative control chicks Presented 25(OH)D$_3$17.5 ng/g liver. When 0.204mJ/$\textrm{cm}^2$ was treated to whole body of chicks, the 25(OH)$D_3$ level was increased to 37.8 ng/g at 12 hr after irradiation, the peak concentration, 40.5 ng /g was appeared at the time of 86 hr, and decreasing trend was shown thereafter until 138 hr, the final time in this study. When 0.408 mJ/$\textrm{cm}^2$ was applied, the 25(OH)$D_3$ content was 36.7 ng /g liver at 12 hr, 61.4 ng/g(maximum value ) was appeared at 42 hr, and 39.5 ng /g at 138 hr. The increased absolute amounts in liver 25(OH)$D_3$ were 23 and 43.9 ng/g as chicks were exposed to UVB light with dose of 0.204 and 0.408mJ/$\textrm{cm}^2$, respectively. Consequently, it was found that when double dose of UVB light was irradiated to the chicks, their liver samples produced nearly double 25(OH)$D_3$ at 42 hr after exposure, and the peak value was presented earlier by 24 hr than that in the low dose treatment.

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