• Title/Summary/Keyword: $CD4^+$

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Growth and Characterization for $CdIn_2S_4/GaAs$ Epilayers ($CdIn_2S_4$ 에피레이어 성장과 특성)

  • Hong, Kwang-Joon
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.11a
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    • pp.239-242
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    • 2004
  • A stoichiometric mixture of evaporating materials for $CdIn_2S_4$ single crystal thin films was prepared from horizontal furnace. To obtain the single crystal thin films, $CdIn_2S_4$ mixed crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by hot wall epitaxy(HWE) system. The source and substrate temperatures were $630^{\circ}C$ and $420^{\circ}C$ respectively. The crystalline structure of single crystal thin films was investigated by the photoluminescence and double crystal X-ray diffraction(DCXD). The carrier density and mobility of $CdIn_2S_4$ single crystal thin films measured from Hall effect by van der Pauw method are $9.01{\times}10^{16}\;cm^{-3}$ and $219\;cm^2/V{\cdot}s$ at 293 K, respectively. From the optical absorption measurement, the temperature dependence of energy band gap on $CdIn_2S_4$ single crystal thin films was found to be $E_g(T)\;=\;2.7116\;eV\;-\;(7.74{\times}10^{-4}\;eV)T^2/(T+434)$. After the as-grown $CdIn_2S_4$ single crystal thin films was annealed in Cd-, S-, and In-atmospheres, the origin of point defects of $CdIn_2S_4$ single crystal thin films has been investigated by the photoluminescence(PL) at 10 K.

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Up-Regulation of Interleukin-4 Receptor Expression by Interleukin-4 and CD40 Ligation via Tyrosine Kinase-Dependent Pathway

  • Kim, Hyun-Il;So, Eui-Young;Yoon, Suk-Ran;Han, Mi-Young;Lee, Choong-Eun
    • BMB Reports
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    • v.31 no.1
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    • pp.83-88
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    • 1998
  • Recently a B cell surface molecule, CD40, has emerged as a receptor mediating a co-stimulatory signal for B cell proliferation and differentiation. To investigate the mechanism of synergy between interleukin-4 (IL-4) and CD40 ligation in B cell activation, we have examined the effect of CE40 cross-linking on the IL-4 receptor expression in human B cells using anti-CE40 antibody. We observed that IL-4 and anti-CD40 both induce IL-4 receptor gene expression with a rapid kinetics resulting in a noticeable accumulation of IL-4 receptor mRNA within 4 h. While IL-4 caused a dose-dependent induction of surface IL-4 receptor expression, the inclusion of anti-CD40 in the IL-4-treated culture, further up-regulated the IL-4-induced IL-4 receptor expression as analyzed by flow cytometry. Pretreatment of B cells with inhibitors of protein tyrosine kinase (PTK) resulted in a significant inhibition of both the IL-4- and anti-CD40-induced IL-4 receptor mRNA levels, while protein kinase C (PKC) inhibitors had no effects. These results suggest that IL-4 and CD40 ligation generate B cell signals, which via PTK-dependent pathways, lead to the synergistic induction of IL-4 receptor gene expression. The rapid induction of IL-4 receptor gene expression through the tyrosine kinase-mediated signal transduction by B cell activating stimuli, would provide cells capacity for an efficient response to IL-4 in the early phase of IL-4 action, and may in part constitute the molecular basis of the reported anti-CD40 co-stimulatory effect on the IL-4-induced response.

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T 임파구와 세포성면역

  • 최철순
    • Journal of the korean veterinary medical association
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    • v.25 no.10
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    • pp.595-606
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    • 1989
  • 항원제시세포(APC)와 보조T세포 간의 협력작용에 의하여 활성화된 작동세포(NK세포, CTL, K세포, 대식세포, 과립구 등)의 종양세포, 이식장기 및 세포내기생세균에 감염된 각종 세포에 대한 세포독성작용은 생체방어를 위한 중요한 세포성면역기전이다. 지난 몇 년간 세포성면역기전에 관한 많은 연구에도 불구하고 T림파구매개성 세포독성작용의 면역생물학적기전은 확실히 밝혀있지 않다. 지금까지 알려진 중요한 연구내용을 요약하면 다음과 같다. 1. 세포독성작용을 나타내는 작동세포로는 NK세포, CTL, K세포, 대식세포/단핵구 및 과립구가 있다. 2. T세포의 세포표면항원분자군(CD)으로는 $CD_{2},\;CD_{3},\;CD_{4}[Ly_{3}T_{4}],\;CD_{5}[=Ly_{1}],\;CD_{7},\;CD_{8}[Ly_{2,3}]$가 있으며 $CD_{4}$는 보조Ttpvhdml 특이마커이고 $CD_{8}$는 세포독성 T세포 및 억압T세포의 특이마커이다. 주요 T세포수용체(TCR)는 $CD_{4}$ 또는 $CD_{8}$ 분자와 가까이 연합된 이향체($TCR-{\alpha}{\beta}/TCR-{\gamma}{\delta}$이며 보조 T세포 $CD_{4}$(마우스 $L_{3}T_{4}$)는 수용체와 연합되어 있는반면 억압 T세포 $CD_{8}(Ly+_{2,3})$는 항원수용체와 연합되어 있다. 3. T세포는 Ti-$CD_{3}$(항원/MHC) 복합체를 통한 '항원가교'에 의한 자극(항원인식)과 $CD_{2}$를 통한 비특이경로에 의하여 활성화(분화증식)된다. 비특이경로를 통한 활성경로에서 T세포($CD_{4}$$CD_{8}$)가 활성화되기 위하여는 보조T세포가 생산하는 IL-2을 요구하며 IL-2의 자극으로 분화증식된 $CD_{8}$는 세포독성능을 나타내지만 $CD_{4}^{+}$는 여전히 세포독성능을 나타내지 못한다. 4. 보조T세포는 class II MHC분자와 연합된 항원을 식별하는 반면 세포독성T세포는 class I MHC 분자와 연합된 항원을 식별한다. 5. 림파구 매개성 세포독성은 접촉(conjugati-on), 탈분극(depolarization), 용해계획(progra-mming), 용해(lysis) 및 재순환(recycling)의 단계를 거쳐 진행된다. 6. 표적세포살해매체로는 perforin / PFP / cy-tolysin, lymphopores, lymphotoxins, protone, cytolytic enzymes가 알려졌으며 세포독성작용은 이들 이외에도 여러 가지 매체를 통한 복합작용으로 추정된다. 7. CTL 매개성 표적세포의 주요 대사변화는 actomyocin ATPase의 증가, phosphocreatine과 ATPase의 소모, ATP 의존성 $Na^{+}/K^{+}$ 펌프작용의 중지, ATP 의존성 $Ca^{2+}$ 유출감소 및 세포내 축적이 관찰된다. 8. $Ca^{2+}$의 축적으로 세포막 교질 침투손상을 주어 수분의 유입을 증가시킴으로써 수포형성, 핵붕괴, 사립체팽화 및 정상세포 구조상실(Zeiosis)이 있다. 결론적으로 CTL 매개성 세포독성작용은 PFP, LT, TNF, 유사 TNF / LT 및 기타 매체를 통한 복합작용이며 세포살해기전은 지속적 대사소모와 정형적 세포구조(핵 및 세포질)의 파괴에 의한 것이다.

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Leukocyte subpopulations of peripheral blood in Korean indigenous cattle vaccinated with attenuated live Akabane virus vaccine (아카바네 생 바이러스 백신 접종에 의한 한우 백혈구 아군의 변화)

  • Park Young-Nam;Son Sung-Mi;Shin Myung-Kyun;Kwon Myung-Sang
    • Korean Journal of Veterinary Service
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    • v.29 no.3
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    • pp.365-376
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    • 2006
  • To identify immune response of leukocytes in peripheral blood of cattle vaccinated with an attenuated live Akabane virus vaccine, leukocytes were reacted with monoclonal antibodies which are specific to bovine lymphocyte surface antigens and assayed by the flow cytometry. Serum neutralizing (SN) test was used to measure antibody titers after vaccination, SN antibody was appeared to 7 days post-vaccination (PV) and 2-8 antibody titers were observed in 14 days PV. Proportion of $CD8^-$ MHC $class II^+$ expressing cells were rapidly increased at 3 days PV. $CD8^+$ MHC $class II^-$ cells were increased at 7 days PV. $CD4^+CD8^-,\;WC^+CD4^-,\;CD4^+CD8^+,\;WC1^-CD4^+, \;WC1^-CD8^+$, and $CD4^-CD8^+$ cells were highly increased at 3, 3, 7, 7, 14, 14 days PV, respectively.

Immunotoxicity among Farmers Exposed to Pesticides (농약 폭로 농민들의 면역독성에 관한 연구)

  • Lim, Chae-Sung;Lee, Kun-Sei;Chang, Soung-Hoon;Lee, Won-Jin
    • Journal of Preventive Medicine and Public Health
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    • v.32 no.3
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    • pp.347-354
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    • 1999
  • Objective: This paper examines the possible toxicity to immune system in farmers chronically exposed to pesticides. Methods : We compared 43 male farmers exposed to pesticides with 29 male residents who had neither past nor current pesticides exposure. The selected variables for studying immunotoxicity were WBC, CD3, CD4, CD8, CD19, CD56, IgG, IgA, IgM, and IL-2. As part of the baseline questionnaires for the immunotoxicity, subjects were asked about kinds of farming, posticides exposure and medical history. Results : None of the variables for studying immunotoxicity showed statistically significant difference between the two groups. Although the results were not statistically significant, CD4 and the CD4/CD8 ratio decreased and CD8 increased. These effects showed a dose response change with exposure level. In the exposed group, the values of CD3, CD4, CD4/CD8 and CD19 decreased and those of the CD8 and CD56 increased compared to the non-exposed group. Also there was higher prevalence of self-reported disease in the exposed group compared to the non-exposed group. Conclusions: Although statistically significant differences in indices of immunotoxicity in farmers exposed to pesticides were not shown, the results suggest that pesticides may decrease immune function. More advanced test methods for immunotoxicity need to be developed and tested in larger population to detect immunotoxic effects of pesticides.

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The Effect of Hwanggigunjung-tang on Imunosuppression induced by Methotrexate in Rat (황기건중탕(黃芪建中湯)이 Methotrexate로 유도된 흰쥐의 면역기능저하(免疫機能低下)에 미치는 영향(影響))

  • Baek, Jung-Han;Koo, Jin-Suk
    • The Journal of Pediatrics of Korean Medicine
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    • v.18 no.1
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    • pp.27-48
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    • 2004
  • Objective: The purpose of this study was to investigate the effect of Hwanggigunjungtang(HGT) on white rats with deteriorated immunity caused by methotrexate. Methods: First, methotrexate was fed to the white rats once a day for 4 days. After the immune responses of the rats are deteriorated, dried extracts of HGT mixed in water was fed to the rats once a day for 14 days. And then we measured the percentage of B-cell and T-cell in peripheral blood, the percentage of CD3+CD4+ T-cell and CD3+CD8+ T-cell of blood sampled from spleen and peripheral region. Results: The percentage of B-cell of peripheral blood was not different statistically. The percentage of T-cell of peripheral blood was increased significantly in HGT group as compared with control group. The percentage of CD3+CD4+ T-cell of peripheral blood was increased significantly in HGT group as compared with control group. The percentage of CD3+CD8+ T-cell of peripheral blood was decreased in HGT group as compared with control group. The percentage of CD3+CD4+ T-cell of spleen was increased significantly in HGT group as compared with control group. The percentage of CD3+CD8+ T-cell of spleen was not different statistically. Conclusion: According to the above results, HGT has an effect of increasing immune responses on white rats with deteriorated immunity caused by methotrexate.

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Effects of GGX on an Ovalbumin-induced Asthma Mice Model (Ovalbumin으로 유발된 천식 동물모델에서 GGX의 효과)

  • Tae-hyeon Kim;Won-kyung Yang;Su-won Lee;Seong-cheon Woo;Seung-hyung Kim;Yang-chun Park
    • The Journal of Internal Korean Medicine
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    • v.44 no.3
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    • pp.294-312
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    • 2023
  • Objective: The purpose of this study is to evaluate the effects of GGX on an ovalbumin (OVA)-induced asthma mice model. Methods: Balb/c mice were challenged with OVA and then treated with three concentrations of GGX (100, 200, and 400 mg/kg). After sacrifice, the bronchoalveolar lavage fluid (BALF) or lungs of the mice were analyzed by fluorescence-activated cell sorting, ELISA, real-time PCR, H&E, Masson's trichrome, PAS and AB-PAS staining, and immunohistofluorescence staining. Results: GGX significantly inhibited the increase of total cells, immune cells (lymphocyte, neutrophils, macrophage, CD4+, CD8+, CD4+CD69+, CD62L-CD44high+, Gr-1+SiglecF-), and the expression of cytokines (IL-4, IL-5, IL-13, IFN-γ) in BALF. It also significantly inhibited the increase of total cells, immune cells (lymphocyte, neutrophils, eosinophil/macrophage, CD3+, CD19+, CD3+CD193+, CD4+, CD8+, CD4+CD69+, CD62L-CD44high+, and Gr-1+SiglecF-), and the expression of IL-13, TARC, and MCP-1 in lung tissue. GGX decreased the severity of histological lung injury and the expressions of STAT3 and GATA3. Conclusion: This study suggests the probability of using GGX for the treatment of asthma by inhibiting inflammatory immune response.

Effect of Dietary Vitamin E Levels on Lipid Peroxidation and Enzyme Activities of Antioxidative System in Brain of Cadmium Administered Rats (식이 Vitamin E 수준이 Cadmium 중독된 흰쥐 뇌조직의 지질과산화와 항산화효소활성에 미치는 영향)

  • 정선영;이순재;양정아
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.25 no.4
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    • pp.575-580
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    • 1996
  • The purpose of this study was to investigate the effect of dietary vitamin E levels on the enzymes such as superoxide dismutase(SOD), glutathione peroxidase(GSH-Px) and glutathione S-transferase (G57) involved in antioxidative defense system and lipid peroxidation in brain of cadmium administered rats. Sprague-Dawely male rats weighing $60\pm5g$ were divided into control and experimental groups. The experimental groups were divided into Cd-0E(vitamin E free diet), Cd-40E(40mg vitamin E/kg diet) and Cd-400E(400mg vitamin E/kg diet) according to the level of vitamin E supplementation. After each group was fed diet ad libitum for 2 or 4 weeks, 2.5mg cadmium per kg body weight was injected intraperitoneally once a day for 4 days. The rats were sacrificed for examination on the next day after the last injection of cadmium. The results are as follows: SOD activities of rat brain were lower in Cd-0E, but had a similar tendency to Cd-40E, Cd-400E groups compared with control group. GSH-Px acivities of rat brain were decreased in Cd-400E, Cd-40E and Cd-0E groups. GST activities of rat brain were decreased in Cd-0E, Cd-40E groups and not significantly different in Cd-400E compared with control group. Thiobarbituric acid reactive substances(TBARS) of rat brain was increased in Cd-0E, Cd-40E, Cd-400E in that order, TBARS was lower in Cd-40E, and Cd-400E by 28.8% and 44%, respectively, than Cd-0E group. The present result suggests that high level of dietary vitamin E protects against lipid peroxidative damage in rat induced by cadmium.

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Optical Properties of Cdlnsub 2Ssub 4 and Cdlnsub 2Ssub 4 : $CdIn_2S_4$$CdIn_2S_4 : Co^{2+}$Single Crystals ($CdIn_2S_4$$CdIn_2S_4 : Co^{2+}$ 단결정의 광학적 특성)

  • Choe, Seong-Hyu;Bang, Tae-Hwan;Kim, Hyeong-Gon
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.48 no.5
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    • pp.296-302
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    • 1999
  • $CdIn_2S_4 and CdIn_2S_4 : Co^{2+}$ singlecrystals of thenormal spinel structure were grown by the C.T.R. method. The optical energy band structure of these compounds had a indirect band gap at the fundamental optical absorption band edge. The direct and the indirect energy gaps are found to be 2.325 and2.179eV for $Cdln_2S_4$ , and 2.303 and 2.169eV for $CdIn_2S_4 and CdIn_2S_4 : Co^{2+}$ at 5K, respectivly. The fundamental absorption band edge of these single crystals shift to a shorter wavelength region with decreasing temperature, and the temperature dependence of the optical energy gaps in these compounds satisfy Varshni equation. The Varshni constants$\alpha and \beta$ of the direct energy gap are given by $13.39{\times}10_{-4}eV/K$ and 509 K for $Cdln_2S_4$ and $29.73{\times}10_{-4} eV/K$ and 1398K for $CdIn_2S_4 and CdIn_2S_4 : Co^{2+}$. The Varshni constants ${\alpha}and {\beta}$ of the indirect energy gap are given by 9.68${\times}10^{-4}$ eV/K 308K for $Cdln_2S_4$ and $13.33{\times}10_{-4}eV/K$ and 440K for $CdIn_2S_4 : Co^{2+}$ respectivly. The impurity optical absorption peaks due to cobalt dopant are observed in $CdIn_2S_4 : Co^{2+}$ single crystal. These impurity optical absorption peaks can be attributed to the electronic transitions between the split energy levels of $Co_{2+}$ ions located at $T_d$ symmetry site of $Cdln_2S_4$ host lattece.

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Immunological mechanism of postherpetic neuralgia and effect of pregabalin treatment on the mechanism: a prospective single-arm observational study

  • Mercan, Aysel;Uzun, Sema Tuncer;Keles, Sevgi;Hacibeyoglu, Gulcin;Yilmaz, Resul;Reisli, Ruhiye
    • The Korean Journal of Pain
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    • v.34 no.4
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    • pp.463-470
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    • 2021
  • Background: Although neuropathic pain is a severe and common pain, its pathophysiology has not been elucidated yet. Studies in recent years have focused on the immune system's role in the pathogenesis of neuropathic pain. The aim of this study was to investigate the role of immunological mechanisms in neuropathic pain and the effect of pregabalin by measuring immunological marker levels in peripheral blood before and after pregabalin treatment in postherpetic neuralgia (PHN) patients with neuropathic pain. Methods: Forty patients diagnosed with PHN were included in the study. CD4, T follicular cells (Tfh: CD4+CXCR5+PD1+), Th17 (CD4+CCR6+ and CD4+IL17A+), regulatory T cells (Treg: CD4+ CD25+foxp3+), Th1 (CD4+ CXCR3+ and CD4+ IFN-γ+) and Th2 (CD4+ IL-4+) cell ratios were measured in peripheral blood samples before treatment and after 3 months of treatment. Results: When immunological marker and inflammation parameter levels were compared before and after treatment, the helper T cell ratio (CD3+, CD4+) was 30.28 ± 12.27% before treatment and 34.93 ± 11.70% after treatment, so there was a statistically significant increase (P = 0.028). Th17 was 4.75 ± 5.02% before treatment and 5.80 ± 3.13% after treatment, and there was a statistically significant increase (P = 0.036). Conclusions: Immunological mechanisms play an essential role in the pathogenesis of neuropathic pain, immunologically based treatment approach will be the critical point of treatment.