• Title/Summary/Keyword: Cd

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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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    • v.7 no.4
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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.

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

  • 최미경
    • Journal of Nutrition and Health
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    • v.27 no.7
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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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A study on the capacitance-voltage characteristics of the CdZnS/CdTe heterojunction (CdZnS/CdTe 이종접합의 커패시턴스-전압 특성에 관한 연구)

  • Lee, Jae-Hyeong
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.15 no.6
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    • pp.1349-1354
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    • 2011
  • In this work, we fabricated the CdZnS/CdTe heterojunction and investigated the C-V characteristics to determine the depletion width and the charge density distribution. A parallel experiment on CdS/CdTe heterojunction was also carried out for comparison. The depletion region width, for CdZnS/CdTe heterojunction, was nearly constant, regardless of bias voltage. However, the depletion region was wider than that of CdS/CdTe heterojunction due to high resistivity of CdZnS film. The interface charge density of CdZnS/CdTe heterojunction was increased linearly with the bias voltage and showed lower values than those for CdS/CdTe junction. The open circuit voltage of CdZnS/CdTe heterojunction solar cells increased with zinc mole ratio due to reducing of the electron affinity difference between CdZnS and CdTe films. However, the increase of series resistance due to the high resistivity of Cd1-xZnxS films results in reducing conversion efficiency.

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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    • v.4 no.3
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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.

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

  • Lee Joon Sang
    • Korean Journal of Environmental Biology
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    • v.23 no.1
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    • pp.47-51
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    • 2005
  • Three-weeks old Commelina communis was transferred to Hoagland solution (Control, 100 μM Cd/sup 2+/, 100 μM Cd/sup 2+/ + 100 μM ABA, 100 μM Cd/sup 2+/+50 mM KCl) and grown for a week in the solution and then a number of physiological activities were investigated. In cases of Cd/sup 2+/ and Cd/sup 2+/ + ABA treatments, the growth of the plants was inhibited to 71 % and 81 %, respectively, when compared with the control, but there were no significant difference of plant growth between Cd/sup 2+/ and Cd/sup 2+/ + KCl- treated plants. In the treatments of Cd/sup 2+/, Cd/sup 2+/ + ABA and Cd/sup 2+/ + KCl total chlorophyll contents were reduced to 32%, 41% and 29%, respectively. In chlorophyll fluorescence experiments, Fv/Fm ratios were also reduced to 14∼20% and about 23%, respectively, according to the light intensity by Cd/sup 2+/ and Cd/sup 2+/+ABA-treated plants. Water stresses were increased by the treatment of Cd/sup 2+/, Cd/sup 2+/ + ABA and Cd/sup 2+/ + KCI. In Cd/sup 2+/ accumulation experiments Cd/sup 2+/ transport into the plant by ABA was not affected, but the accumulation of Cd/sup 2+/ into the roots was elevated to 13% when compared with the control. Cd/sup 2+/ transport into the root was markedly inhibited to 60% by KCl. Therefore, it could be concluded that ABA did not reduce the toxicities of Cd/sup 2+/, but enhanced Cd/sup 2+/ - induced toxicities and KCl showed no effect on Cd/sup 2+/ - induced toxicities.

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

  • Im, H.B.;Roh, J.S.
    • Proceedings of the KIEE Conference
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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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    • v.20 no.5
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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.

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

  • 노재성;임호빈
    • Electrical & Electronic Materials
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    • v.1 no.1
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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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The Effect of Dietary Cu and Fe on the Cd Accumulation in Long-Term Cd Poisoned Rats (장기간 카드뮴에 중독된 흰쥐에서 카드뮴 축적에 대한 식이 구리와 철분의 효과)

  • 김애정
    • Journal of Nutrition and Health
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    • v.29 no.1
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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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The Analysis of CdS and CdTe Thin Film at the Processes of Manufacturing CdTe Solar Cells (CdTe 태양전지 제조 공정에 따라 변화하는 CdS와 CdTe 박막의 물성 변화 분석)

  • Chun, Seungju;Jung, Younghun;Choi, Suyoung;Tark, Sung Ju;Kim, Jihyun;Kim, Donghwan
    • 한국신재생에너지학회:학술대회논문집
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    • pp.106.2-106.2
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    • 2011
  • 다층 박막 구조로 이루어진 CdS/CdTe 태양전지의 경우, 각각의 박막이 다양한 제조 공정을 거치면서 물성특성의 변화를 겪게 된다. 각각의 박막이 고온의 열처리 공정과, $CdCl_2$ 용액 처리 및 후면 산화막 제거 공정 등을 거치게 되면서 겪게 되는 물성 변화 분석을 살펴보고자 한다. 각각의 박막 제조 방식은 일반적으로 사용되는 방식으로, CdS의 경우는 용액성장법(Chemical Bath Deposition, CBD), CdTe의 경우는 근접승화법(Closed Space Sublimaition, CSS)을 사용했으며, X-Ray Diffractometer (XRD), Raman spectroscopy, Field Emission Scanning Electron Microscope (FE-SEM), Energy Dispersive Spectroscopy (EDS), X-ray Photoelectron Spectroscopy (XPS) 등을 이용하여 분석하였다. 각각의 셀 제조 공정을 거치면서 CdS, CdTe 박막들은 결정, 광 특성, 성분 변화를 보였다.

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