• IMMUNE NETWORK
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• 제4권3호
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• pp.166-175
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• 2004

Background: Telomerase, a ribonucleoprotein enzyme capable of synthesizing telomeric repeats, attracts attention for its possible role in determining the replicative capacity of normal somatic cells, transformed cells, and cells of the germline lineage. Differently from normal somatic cells with no telomerase activity, normal lymphocytes has been reported to have telomerase activity comparable to that found in transformed cells during development and activation, which substantiate a role in supporting the capacity of lymphocytes for extensive clonal expansion. Methods: Here, in order to define the telomerase regulation in murine T lymphocytes, telomerase activity in cloned murine $CD8^+$ T cells and naive $CD8^+$ T cells isolated from C57BL/6 mice was examined. Next, the regulatory mechanism of telomerase activity at transcriptional and post- translational levels was investigated by determining the expression level of the TERT protein, a key component for telomerase activity. Results: It was demonstrated that telomerase activity was expressed in an inactivated state as well as in an activated state in the murine $CD8^+$ T lymphocytes by using TRAP assay. The increase of telomerase activity was partially dependent on the net increase of TERT expression. Also, telomerase activity was decreased after treatment with protein kinase inhibitors, indicating that telomerase activation was prevented by inhibition of phosphorylation. Conclusion: Therefore, these results suggest that telomerase activity is constitutively expressed in the murine resting T lymphocytes and controlled by both transcriptional regulation and post- ranslational modifications.

• Radiation Oncology Journal
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• 제11권2호
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• pp.219-225
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• 1993

각 방사선량의 조사에 따른 사람 정상임파구, 마우스 정상임파구, 그리고 EL-4마우스 백혈병 세포의 DNA double strand breaks 발생율에 대하여 비교분석 하였던 바 다음과 같은 결과를 얻었다. LPS와 PHA를 첨가하여 각각 배양한 마우스 정상임파구의 DNA double strand breaks의발생율을 strand scission factor의 기울기로 비교평가해 본 바 LPS를 첨가배양한 군이 DNA DSB가 더 많이 형성되었다(P<0.005). 이것으로 볼 때 DNA double strand breaks발생에 있어서는 B cells이 T cells보다 더 민감하였다. 또한 EL-4 백혈병 세포는 정상 임파구보다 유의하게 DNA DSB가 더 많이 형성된 것이 관찰되었다(p<0.005). 한편 사람 정상임파구와 마우스 정상임파구 사이의 intrinsic radiosensitivity는 시험관내 실험에서 비교적 유사한 kinetics를 나타냈으나, 마우스 정상임파구가 사람 정상임파구보다 DNA DSB수율이 더 낮았다. 그래서 방사선을 조사하고 3.5시간이 지난후에 $10\%$ DNA DSB발생에 필요한 선량을 두 군간에 비교평가해 본 바 마우스 정상임파구의 선량이 더 높게 나타났다. 이상의 실험결과를 정확하게 설명하기는 어 렵지만 아마도 환경적인 요인과 유전적인 요인 때문인 것으로 사료되었다. 그리고 본 연구결과는 방사선조사에 따른 임상반응의 이해와 cytometric assessment의 방사선 생물학적 parameter로 이용될 수 있을 것으로 판단되었다.

• 동의생리병리학회지
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• 제23권6호
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• pp.1385-1391
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• 2009

The purpose of this research was to investigate the effects of the extracts of Glycyrrhiza uralensis (GE) and the combined extracts of Glycine max Merr. and Glycyrrhiza uralensis (GGE) on the activity of murine splenocytes and macrophages. GE and GGE were administered orally twice a day for 7 days at the dose of 500 mg/kg. GE decreased the viability of T- and B-lymphocytes in splenocytes, but GGE increased the viability of B-lymphocytes in splenocytes. GE increased the population of B-lymphocytes in splenocytes, but decreased the population of T-lymphocytes and splenic $CD4^+$ cells. Also, GGE decreased the population of B-lymphocytes in splenocytes, but increased the population of T-lymphocytes and splenic $CD4^+$ cells. Furthermore, GE and GGE enhanced the phagocytic activity of peritoneal macrophages and the production of nitric oxide. These results suggest that the regulative action of immune response of GGE is more potent than their of GE.

• 동의생리병리학회지
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• 제23권4호
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• pp.825-830
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• 2009

The purpose of this research was to investigate the effects of Calendula officinalis extract (CE) on the activation of murine lymphocytes and macrophages. CE was administered p.o. once a day for 7 days at the concentration of 500 mg/kg. The administration of CE increased the viability of thymocytes, but decreased the viability of splenocytes. Also, CE increased the viability of thymocytes and splenocytes at the concentration of $5{\mu}g$/ml in vitro. The administration of CE did not affect the population of thymic $CD4^+$/$CD8^+$ cells and splenic $CD4^+$/$CD8^+$ cells. Furthermore, the administration of CE enhanced the phagocytic activity of peritoneal macrophages, but decreased the phagocytic activity in vitro. CE decreased the production of nitric oxide from peritoneal macrophages in vivo and in vitro system. These results suggest that CE enhance of cell viability by a direct influence on thymocytes and phagocytic activity by an indirect influence on peritoneal macrophages.

• 약학회지
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• 제31권4호
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• pp.213-218
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• 1987

Twenty species of higher fungi growing in the wild were collected and studied extensively for their lectin activities by using erythrocytes of human, rabbit and mouse blood. In total, 14 species demonstrated hemagglutination with some kinds of erythrocytes. Of twenty species, eight (Boletus edulis, B. splendidus, Clavaria zollingeri, Lactaritis subzonarius, L. volemus, Russula cutefracta, Pholiota squarrosa, and P. aspera) were shown lymphoagglutination with murine splenic lymphocytes. Protein contents were estimated from the crude lectin fraction. Above mentioned eight species contained relatively high amounts of proteins than other mushrooms. Since these species had coincidently, hiig emagglutinating activity as well, we could define them as lectin-containeing mushrooms. Some species also contained mitogenic lectins toward murine splenic lymphocytes.

• 약학회지
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• 제39권3호
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• pp.260-267
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• 1995

A lectin from the edible mushroom, Lentinus edodes, was purified through physiological saline extraction, ammonium sulfate fractionation and column chromatographies. On polyacrylamide gel electrophoresis, 0.05M fraction from hydroxyapatite column exhibited adjacent four sharp bands. The partially purified lectin agglutinated the erythrocytes of rabbit, mouse and rat, but not agglutinated human erythrocytes. The lectin's mitogenic effects were tested by its application to human and murine splenic lymphocytes. The results showed that the 0.05M fraction from hydroxyapatite was mitogenic, and the optimal dose of Lentinus edodes lectin was slightly lower than Con A by the culture with murine splenic and human peripheral lymphocytes. Meanwhile, its ability to agglutinate transformed cells was tested by its administration to continuous cell lines L1210 and HeLa cells. The leetin was found to be an agglutinin of tumor cell lines tested by L1210 and HeLa cells.

• 약학회지
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• 제35권5호
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• pp.444-455
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• 1991

Two kinds of new lectin fractions (LOA-I, LOA-II) were obtained from loach (Misgurnus spp.) meat by 0.15 M NaCl extraction, salt fractionation, ion exchange and hydroxyapatite column chromatographies. On polyacrylamide gel electrophoresis, LOA-I exhibited one major and a few minor bands, but LOA-II exhibited three minor bands. The partially purified loach lectins agglutinated not only erythrocytes of human B and AB type, rabbit, dog, but also murine splenic lymphocytes. Agglutinability was relatively labile at various pH and stable at increasing temperature, but was not affected by tested several metal ions. By the sugar specificity test, D-glucosamine and metyl-$\beta$-galactopyranose inhibited agglutinating activity at a final concentration of 3 mM. The lectins contained relatively high amounts of aspartic acid, valine and leucine, but sulfur containing amino acids, cystein, methionine and isoleucine were not determined. LOA-I, LOA-II lectins were nonmitogenic toward murine lymphocytes.

• 한국동물학회:뉴스레터
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• 제12권2호
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• pp.87.2-87
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• 1995

No Abstract, See Full Text

• 한국동물학회:학술대회논문집
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• 한국동물학회 1995년도 한국생물과학협회 학술발표대회
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• pp.213.2-213
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• 1995

No Abstract, See Full Text

• Parasites, Hosts and Diseases
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• 제45권3호
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• pp.175-180
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• 2007

In order to determine the role of Peyer's patch lymphocytes (PPL) in self-clearing of Cryptosporidium parvum infection in murine models, changes in PPL subsets, their cytokine expression, and in vitro IgG1 and IgA secretions by PPL were observed in primary- and challenge-infected C57BL/6 mice. In primary-infected mice, the percentages of CD4+ T cells, CD8+ T cells, slgA+ B cells, IL-2+ T cells, and $IFN-{\gamma}+$ T cells among the PPL, increased significantly (P < 0.05) on day 10 post-infection (PI). Secretion of IgG1 and IgA in vitro by PPL also increased on day 10 PI. However, all these responses, with the exception of IgG1 and IgA secretions, decreased in challenge-infected mice on day 7 post-challenge (= day 13 PI); their IgG1 and IgA levels were higher (P > 0.05) than those in primary-infected mice. The results suggest that murine PPL play an important role in self-clearing of primary C. parvum infections through proliferation of CD4+, CD8+, IL-2+, and $IFN-{\gamma}+$ T cells, and IgG1 and IgA-secreting 8 cells. In challenge infections, the role of T cells is reduced whereas that of 8 cells secreting IgA appeared to be continuously important.