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Role for CD40 and CD40L Expression in Generating CD8 T Cell Response to Minor Histcompatibility Antigen, H60

  • Jung, Kyoung-Min;Choi, Eun-Young
    • IMMUNE NETWORK
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    • 제7권4호
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    • pp.173-178
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    • 2007
  • Background: We studied the role for expression of CD40 and CD40L by CD4 and CD8 T cells in the generation of CD8 T cell response to minor histocompatibility antigen, H60. H60 is a cellular antigen to which CD8 responses require CD4 T cell help. Methods: CD40- or CD40L-deficient mice were adoptively transferred with normal CD4 or CD8 T cells or with memory CD4 or CD8 T cells, and were immunized with male H60 congenic splenocytes to induce CD8 T cell response to H60. Peripheral blood CD8 T cell from the immunized mice were stained with the H60 tetramer. Results: CD8 T cell response to H60 was not induced in both CD40- and CD40L-deficient mice. Adoptive transfer of $CD40^{+/+}$ CD8 T cells into CD40-deficient mice did not compensate the defect in inducing CD8 T cell response to H60, while the H60-specific CD8 T cells were activated in the CD40-deficient mice that were adoptively transferred with $CD40^{+/+}$ CD4 T cells. Adoptive transfer of $CD40L^{+/+}$ CD4 T cells into CD40L-deficient mice induced primary CD8 T cell response for H60 and the presence of $CD40L^{+/+}$ CD4 T cells was required even for memory CD8 T cells response to H60. Conclusion: Our results suggest that the CD40-CD40L interaction mediates the delivery of CD4 T cell help to naive and memory H60-specific CD8 T cells. While the expression of CD40L by CD4 T cells is essential, signaling through CD40 on CD8 T cells is not required for the induction of CD8 T cell response to H60.

CdZnS/CdTe 이종접합의 커패시턴스-전압 특성에 관한 연구 (A study on the capacitance-voltage characteristics of the CdZnS/CdTe heterojunction)

  • 이재형
    • 한국정보통신학회논문지
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    • 제15권6호
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    • pp.1349-1354
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    • 2011
  • 본 연구에서는 CdZnS와 CdTe로 구성되는 이종접합 소자를 제작하고 커패시턴스-전압 특성을 조사하였다. CdS/CdTe 접합의 경우, 역방향 바이어스가 증가함에 따라 공핍층의 폭이 커져 커패시턴스 값이 약간 감소하였으나 CdZnS/CdTe 접합에서는 CdTe 박막 내에서의 공핍층 폭이 바이어스에 크게 영향을 받지 않아 커패시턴스 값이 역방향 바이어스에 따라 거의 변화가 없었다. 바이어스 전압을 인가하지 않은 상태에서의 공핍층 폭은 높은 CdZnS 박막의 비저항 및 낮은 캐리어 농도로 인해 CdS/CdTe 접합보다 CdZnS/CdTe 접합에서 보다 큰 값을 나타내었다. CdZnS/CdTe 태양전지의 개방전압은 Zn의 비율이 커짐에 따라 CdZnS 박막과 CdTe 박막의 전자 친화력 차이의 감소로 인하여 크게 증가하였으나, Zn 비율이 0.35 이상인 경우 오히려 감소함을 알 수 있었다. 또한 CdZnS 박막의 높은 비저항이 태양전지의 직렬저항을 상승시켜 전지의 변환 효율은 오히려 감소함을 알 수 있었다.

카드뮴의 장기 중독시 철분의 섭취 수준이 흰쥐의 체내 카드뮴 축적에 미치는 효과 (Effect of Dietary Iron Levels on the Cadmium Accumulation in Cadmium Poisoned Rats)

  • 최미경
    • Journal of Nutrition and Health
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    • 제27권7호
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    • pp.709-716
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    • 1994
  • This study was undertaken to investigate the effect of dietary Fe levels on Cd accumulation in Cd poisoned rats. Forty male weaning Sprague Dawley rats weighing 80-90g were divided into 4 groups(LFe : low Fe, LFeCd : low Fe and Cd, AFe : adequate Fe, AFeCd : adequate Fe and Cd) according to Cd administration(Cd : 0 or 50ppm in drinking water) and Fe levels (Fe : 6 or 40ppm in diet) for 12 weeks. The food intake and weight gain of LFe and LFeCd were significantly lower than those of AFe and AFeCd(p<0.01, p<0.001). The water intake was not affected significantly by Cd and Fe, therefore Cd intake was no significant difference between groups. The Cd accumulation of kidney in LFeCd was significantly higher than those of AFeCd(p<0.001). But the Cd accumulations of brain, liver and spleen were not significantly different between Cd groups and without Cd groups. The serum Cd content and urinary Cd excretion of LFeCd was significantly higher than those of AFeCd(p<0.01, p<0.01). But the fecal Cd excretion of LFeCd was significantly lower than that of AFeCd(p<0.001). The Cd retention, Cd retention rate, and apparent Cd digestibility of LFeCd were significantly higher than those of AFeCd(p<0.001, p<0.001, p<0.001). It was concluded that adequate Fe supplementation have protective effects on the long term Cd poisoning in rats.

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Abscisic acid가 $Cd^{2+}$에 의한 닭의장풀이 생리적 반응에 미치는 영향 (The Effects of Abscisic Acid (ABA) on $Cd^{2+}$-induced Physiological Responses in Commelina communis L.)

  • 이준상
    • 환경생물
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    • 제23권1호
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    • pp.47-51
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    • 2005
  • 3주간 정상적으로 생장한 닭의장풀을 Hoagland 용액 (대조구, 100 μM Cd/sup 2+/, 100 μM Cd/sup 2+/ + 100 μM ABA, 100 μM Cd/sup 2+/+50 mM KCl)에서 1주간 수경재배 한 후 생장, 엽록소 함량, 엽록소 형광, 수분 스트레스와 Cd/sup 2+/의 축적을 조사하여 Cd/sup 2+/ 축적과 식물의 생리적 반응과의 연관성을 찾고자 하였다. 식물의 생장에서 Cd/sup 2+/과 Cd/sup 2+/+ABA 처리구는 대조구에 비해 각각 71%와 81%생장이 감소하였고, Cd/sup 2+/+KCl 처리구는 Cd/sup 2+/ 처리구와 생장에 큰 차이가 없었다. 엽록소 함량은 Cd/sup 2+/, Cd/sup 2+/+ABA, Cd/sup 2+/+KCl 처리구에서 대조구에 비해 각각 32%, 41%, 29% 억제되었다. 엽록소 형광 측정의 경우 Cd/sup 2+/ 처리구는 대조구에 비해 모든 광도에서 Fv/Fm 비율이 14∼20% 감소하였다. Cd/sup 2+/+ABA 처리구는 Fv/Fm 비율이 23% 내외에서 감소하였으며, Cd/sup 2+/+KCl 처리구는 Cd/sup 2+/ 처리구와 Fv/Fm 비율에 큰 차이가 없었다. 수분 스트레스에 대한 Cd/sup 2+/과 ABA 처리 효과는 Cd/sup 2+/ 처리구에서 대조구에 비해 2.5배, Cd/sup 2+/+ABA 처리구에서 3배, Cd/sup 2+/+KCl 처리구에서 2.25배 각각 수분 스트레스가 증가하였다. Cd/sup 2+/ 수송에 대한 ABA의 효과를 살펴보면, Cd/sup 2+/+ABA 처리구에서 ABA는 Cd/sup 2+/ 수송을 억제하거나 촉진시키지는 않았지만 Cd/sup 2+/의 뿌리 축적을 약 13% 심화시켰다. 반면에 KCl은 뿌리 내 Cd/sup 2+/ 축적을 약 60% 억제시켰다. 따라서 대표적인 스트레스 내성 호르몬 ABA는 Cd/sup 2+/축적으로 인해 발생된 식물의 생리적 독성을 완화시켜 주지 못했으며. 오히려 독성을 증가시켰다.

Cd 입도 크기가 CdS/CdTe 태양전지의 특성에 미치는 영향 (The Effects of Cd particle size on the Properties of Cds/CeTe Solar Cells)

  • 임호빈;노재성
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1987년도 정기총회 및 창립40주년기념 학술대회 학회본부
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    • pp.200-202
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    • 1987
  • Sintered CdS films on glass substrate with low electrical resistivity and high optical transmittance have been prepared by coating and sintering method. All-polycrystalline CdS/CdTe solar cells with different microstructure and properties of CdTe layer were fabricated by coating a number of CdTe slurries, which consisted of Cd and Te powders, an appropriate amount of propylene glycol and 2 or 7.5 w/o $CdC1_2$, on the sintered CdS films and by sintering the glass-CdS-(Cd+Te) composites at various temperature. To explore the dependence of the solar efficiency on the preparation conditions of the CdTe layer, Cd powder with an average particle size of $0.3{\mu}m$ or $5{\mu}m$ was prepared. The use of Cd with finer particles forms more dense or uniform microstructure of the nuclear of CdTe during the heating. Therefore the use of Cd with finer particles improves the efficiency of the sintered CdS/CdTe solar cell by improving the microstructure of sintered CdTe layer. But the difference of solar efficiency by varing a particle size of Cd is decreased with increasing amount of $CdC1_2$ in the (Cd+Te) layer. All-polycrystalline CdS/CdTe solar cells with an efficiency of 10.2% under solar irradiation have been fabricated using a Cd with finer particles.

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Molecular association of CD98, CD29, and CD147 critically mediates monocytic U937 cell adhesion

  • Kim, Mi-Yeon;Cho, Jae Youl
    • The Korean Journal of Physiology and Pharmacology
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    • 제20권5호
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    • pp.515-523
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    • 2016
  • Adhesion events of monocytes represent an important step in inflammatory responses induced by chemokines. The ${\beta}1$-integrin CD29 is a major adhesion molecule regulating leukocyte migration and extravasation. Although several adhesion molecules have been known as regulators of CD29, the molecular interactions between CD29 and its regulatory adhesion molecules (such as CD98 and CD147) have not been fully elucidated. Therefore, in this study, we examined whether these molecules are functionally, biochemically, and cell-biologically associated using monocytic U937 cells treated with aggregation-stimulating and blocking antibodies, as well as enzyme inhibitors. The surface levels of CD29, CD98, and CD147 (but not CD43, CD44, and CD82) were increased. The activation of CD29, CD98, and CD147 by ligation of them with aggregation-activating antibodies triggered the induction of cell-cell adhesion, and sensitivity to various enzyme inhibitors and aggregation-blocking antibodies was similar for CD29-, CD98-, and CD147-induced U937 cell aggregation. Molecular association between these molecules and the actin cytoskeleton was confirmed by confocal microscopy and immunoprecipitation. These results strongly suggest that CD29 might be modulated by its biochemical and cellular regulators, including CD98 and CD147, via the actin cytoskeleton.

(Cd+Te)막의 소결조건이 CdS/CdTe 태양전지의 특성에 미치는 영향 (Effects of sintering conditions of (Cd+Te) films on the properties of sintered CdS/CdTe solar cells)

  • 노재성;임호빈
    • E2M - 전기 전자와 첨단 소재
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    • 제1권1호
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    • pp.26-34
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    • 1988
  • Sintered CdS/CdTe solar cells have been farbricated by coating a (Cd+Te) slurry on sintered CdS films followed by the sintering at 625.deg.C for one hour with various heating rates. When cadmium and tellurinm powders are used instead of CdTe powder to form CdS/CdTe junction, CdTe is formed in the temperature range of 290.deg.C-400.deg.C. The microstructure of the CdTe films depends strongly on the heating rate of the sintering due to the low melting temperature and the high vapor pressure of the elemental Cd and Te. An optimum heating rate obtain CdTe films with uniform and dense microstructure which, in turn, improves the efficiency of the sintered CdS/CdTe solar cells. All-polycrystalline CdS/CdTe solar cells with an efficiency of 9.57% under 50mW/cm$^{2}$ tungsten light have been farbricated by using a heating rate of 14.deg.C/min.

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장기간 카드뮴에 중독된 흰쥐에서 카드뮴 축적에 대한 식이 구리와 철분의 효과 (The Effect of Dietary Cu and Fe on the Cd Accumulation in Long-Term Cd Poisoned Rats)

  • 김애정
    • Journal of Nutrition and Health
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    • 제29권1호
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    • pp.70-76
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    • 1996
  • This study was undertaken to investigate the effect on the Cd accumulation in long-term Cd poisoned rats. 40 male weaning Sprague Dawley rats weighting 80-90g were divided into 4 groups (LCuLFeCd : low Cu, Fe and Cd group, ACuLFeCd : adequate Cu, low Fe and Cd group, ACuAFeCd : adequate Cu, adequate Fe and Cd group) according to Cu and Fe levels (Cu 0.5ppm, 8.5ppm : Fe 6ppm, 40ppm) for 12 weeks. There were no significant difference in water intake, feed intake, and body weight gain according to dietary Cu and Fe consumption. But the mean food intake and body weight gain of adequate Fe groups(LCuAFeCd, ACuAFeCd) were higher than those of deficient Fe groups (ACuLFeCd, LCuFeCd)in long-term Cd poisoned rats. The mean Cd levels of serum, liver, kidney, and urine in ACuAFeCd group were lower than those of Cu and /or Fe deficient groups. But the mean fecal Cd excretion of ACuAFeCd group was higher than that of Cu and/or Fe deficient groups. And the mean Cd retention amount of ACuAFeCd group was lower than those of Cu and/or Fe deficinet groups. In conclusion, these results provide an evidence that adequate Cu and Fe intakes can decrease Cd accumulation in rats. Therefore, in the point of increasing environmental Cd contamination, adequate Cu and Fe intakes must be suggested to prevent Cd accumulations.

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카드뮴화합물별(化合物別) 수도(水稻) 흡수(吸收) 및 생육(生育)에 미치는 영향(影響) (Effect of Various Cadmium Compounds on the Growth and Cadmium Uptake of Paddy Rice)

  • 김규식;김복영;박영선
    • 한국환경농학회지
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    • 제2권1호
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    • pp.6-12
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    • 1983
  • 수도(水稻)에 대(對)한 cadmium화합물(化合物)의 형태(形態)에 따른 피해농도(被害濃度) 및 cadmium흡수정도(吸收程度)를 구명(究明)하기 위(爲)하여 $Cd(NO_3)_2$, $CdCl_2$, $CdSo_4$, $CdCo_3$ 및 CdS 등(等)의 화합물(化合物)을 토양(土壤)에 Cd로서 0, 5, 10, 25, 50 ppm처리(處理)하여 수도(水稻)의 수양(收量)에 미치는 농도(濃度)와 수도체중(水稻體中)의 cadmium함량(含量)을 조사(調査)한 바 그 결과(結果)는 다음과 같다. 1) 토양중(土壤中) cadmium처리농도(處理濃度)가 높을수록 식물체(植物體) 경엽(莖葉) 및 현미중(玄米中) cadmium함량(含量)은 증가(增加)하였으나 수량(收量)은 높은 농도(濃度)에서 감소(減小)되었다. 2) 수양감수(收量減收)를 가져오는 토양중(土壤中) Cd의 농도(濃度)는 $Cd(NO_3)_2$ : 12.9ppm, $CdSO_4$ : 21.5ppm, $CdCl_2$ : 25.8ppm $CdCO_3$ : 33.2ppm, CdS : 97.6ppm 이었다. 3) 현미중(玄米中) cadmium함량(含量)이 1.0ppm이 되는 토양중(土壤中) Cd의 농도(濃度)는 $cd(NO_3)_2$ : 13.8ppm, $CdCl_2$ : 14.4ppm, $CdSO_4$ : 16.9ppm, $CdCO_3$ : 19.2ppm이었다. 4) cadmium의 현미흡수양/지상부흡수량비(玄米吸收量/地上部吸收量比)는 최고(最高) 분얼기(分蘖期) 28%, 유수형성기(幼穗形成期) 20%, 수확기(收穫期) 15%이었다. 5) 유수형성기(幼穗形成期) 식물체(植物體) 경엽중(莖葉中) cadmium함량(含量)과 현미중(玄米中) cadmium함량(含量)과의 관계(關係)는 $Y=0.067-0.0028x+0.007x^2$으로 고도(高度)의 유의성(有意性)이 있었다. 6) 용해도(溶解度)가 낮은 cadmium화합물(化合物)이 시험후(試驗後) 토양중(土壤中) 가용성(可溶性) cadmium합량(合量)이 낮았다.

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Differential Signaling via Tumor Necrosis Factor-Associated Factors (TRAFs) by CD27 and CD40 in Mouse B Cells

  • Woo, So-Youn;Park, Hae-Kyung;Bishop, Gail A.
    • IMMUNE NETWORK
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    • 제4권3호
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    • pp.143-154
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    • 2004
  • Background: CD27 is recently known as a memory B cell marker and is mainly expressed in activated T cells, some B cell population and NK cells. CD27 is a member of tumor necrosis factor receptor family. Like CD40 molecule, CD27 has (P/S/T/A) X(Q/E)E motif for interacting with TNF receptor-associated factors (TRAFs), and TRAF2 and TRAF5 bindings to CD27 in 293T cells were reported. Methods: To investigate the CD27 signaling effect in B cells, human CD40 extracellular domain containing mouse CD27 cytoplamic domain construct (hCD40-mCD27) was transfected into mouse B cell line CH12.LX and M12.4.1. Results: Through the stimulation of hCD40-mCD27 molecule via anti-human CD40 antibody or CD154 ligation, expression of CD11a, CD23, CD54, CD70 and CD80 were increased and secretion of IgM was induced, which were comparable to the effect of CD40 stimulation. TRAF2 and TRAF3 were recruited into lipid-enriched membrane raft and were bound to CD27 in M12.4.1 cells. CD27 stimulation, however, did not increase TRAF2 or TRAF3 degradation. Conclusion: In contrast to CD40 signaling pathway, TRAF2 and TRAF3 degradation was not observed after CD27 stimulation and it might contribute to prolonged B cell activation through CD27 signaling.