• 치과방사선
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• 제29권1호
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• pp.105-117
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• 1999

Purpose: Ionizing radiations have been reported as an apoptosis initiating stimulus in various cells and it has established that sustained elevations in [Ca/sup 2+/] can lead to DNA fragmentation by Ca/sup 2+/-dependent endonucleases, ultimately resulting in apoptotic cell death. The previous experiments have been reported by using primarily thymocytes and lymphocytes and the change of [Ca/sup 2+/] was measured only by minutes or hours respectively. We need to evaluate [Ca/sup 2+/] in both several minutes and hours after irradiation of radiation of radiation therapy and verify the apoptotic cells. Materials and Methods: We have measured [Ca/sup 2+/] in human gingival epitheloid cancer cell with 10Gy irradiation, at minutely intervals and hourly intervals using digitized video-intensified fluorescence microscopy and the fluorescent Ca/sup 2+/ indicator dye, fura-2. In order to find out that the transient rise in [Ca/sup 2+/] could induced apoptosis, cells were incubated for 1 hour at 37℃ with TdT enzyme, rinsed and resuspended containing fluorescence and observed under a confocal fluorescence microscope. MTT assay was done to determine cell activity and LDH assay was done to determine the amount of necrotic cells. Results: After irradiation, the transient and temporal increasing of [Ca/sup 2+/] in the KB cells was founded. Though, there was no change in the intracellular [Ca/sup 2+/] at 30 minutes and 2 hours after irradiation. We could detect of DNA fragmented cells at 4 hours after 10Gy irradiated cells. There were no significant differences between 4 hour, 1 day, 3 day cells. There were no significant differences in MTT and LDH assay between the irradiated group and the control group after 4 hours and 1 day. Though after 3 days there were differences in MTT and LDH assay between the irradiated group was significantly decreased than the control group, in LDH assay the number of necrotic cell death of the irradiated was higher than the control group. Conclusion: In KB cells there were incipient and temporal increasing of the [Ca/sup 2+/] with 10Gy irradiation and the apoptosis was founded from 4 hours later which was earlier than seeing of the change of the amount of the cellular ability and necrosis.

• 생명과학회지
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• 제17권7호통권87호
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• pp.923-930
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• 2007

성체흰쥐의 경우 항암제인 싸이클로포스파마이드 (CY)처리로 퇴축된 가슴샘은 2주 후에 정상조직으로 재생된다. 가슴샘 발생과정에서 이미 알려진 Wnt신호전달의 중요성과는 달리 성체의 가슴샘 재생과정에서 그 역할에 관해서는 알려진 바 전혀 없다. 본 연구의 목적은 발생중인 가슴샘 상피세포에서 발현이 증가된다고 이미 알려져 있는 Wnt7b가 성체의 가슴샘재생과정에서 어떤 발현 양상을 보이는지를 조사하는 것이다. Wnt7b는 가슴샘의 급성 퇴축 이후 3일째 되는 시기에 mRNA와 단백질의 양이 급격히 증가 하였으며, 이중 면역 염색 형광법을 통해 큰포식 세포와 위치적 분포가 일치함을 확인하였다. 또한, Wnt7b유전자의 발현 조절 기전을 밝히기 위해 Wnt7b의 Reporter Vector를 제작하여 Luciferase assay를 이용하여 상위의 신호를 분석하였고, 그 결과 Wnt7b는 RANKL에 의해 그 발현이 감소된다는 사실을 처음으로 밝혔다. 따라서, 본 연구 결과들을 통해 Wnt 7b는 가슴샘의 급성 퇴축 초기 과정에서 나타나는 손상된 세포를 처리하는 큰포식 세포의 기능 조절에 관여할 것으로 생각된다.

• 약학회지
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• 제35권3호
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• pp.174-181
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• 1991

These experiments were conducted to investigate the effects of glycyrrhizin(GL) and glycyrrhetinic acid(GA) on histamine synthesis, lymphocyte blastogenesis in C57BL/6J mice splenocytes, IL-1 production, $Ca^{2+}$ uptake by macrophage-like P388D$_{1}$ cells and plaque forming cell assay against SRBC. Histamine contents, lymphocyte blastogenesis, IL-1 activity, $Ca^{2+}$ uptake and plaque forming cell were determined by enzyme isotope method, [sup 3/H]-thymidine incorporation, C3H/HeJ mouse thymocytes proliferation, the addition of 5 $\mu$Ci/ml $^{45}$Ca$^{2+}$ to P388D$_{1}$, cell suspension and assay to sheep red blood cell, respectively. Cytotoxicity, which was expressed as 50% mortality, was occurred by the addition of GL(10$^{-3}$M) and GA(10$^{-4}$M). Histamine production in mouse spleen cell culture was significantly increased by the addition of 0.25 $\mu\textrm{g}$/ml of Con A, after 48 hour incubation. Con A dependent T-lymphocyte proliferation was also enhanced by the addition of 0.25 .mu.g/ml of Con A. The effects of GL on histamine contents and T-lymphocyte proliferation were significantly decreased at high dose (10$^{-5}$M), while IL-1 activity was remarkably suppressed by 10$^{-8}$~10$^{-4}$M of GL. $Ca^{2+}$ uptake was not changed, but antibody production was increased by GL(10 mg/kg). GA inhibited histamine contents at 10$^{-9}$~10$^{-7}$ and depressed Con A (0.25 $\mu\textrm{g}$/ml) dependent T-lymphocyte proliferation at 10$^{-7}$~10$^{-5}$M of GA, but increased suboptimal dose (Con A 0.1 $\mu\textrm{g}$/ml) at 10$^{-9}$~10$^{-7}$M of GA. IL-1 activity was suppressed by 10$^{-8}$~10$^{-4}$M of GA and $Ca^{2+}$ uptake was enhanced by 10$^{-9}$~10$^{-6}$ of GA, but antibody production was not changed by GA. From the above results, it is suggested that GL and GA have immuno-regulatory action. GL decreased cell-mediated immune response, and increased humoral immune response at high dose. On the other hand, low dose of GA enhanced cell-mediated immune response, while high doses of GA decreased humoral immune reaction.

• IMMUNE NETWORK
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• 제20권5호
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• pp.43.1-43.11
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• 2020

Capicua (CIC) is a transcriptional repressor that regulates several developmental processes. CIC deficiency results in lymphoproliferative autoimmunity accompanied by expansion of CD44^hiCD62L^lo effector/memory and follicular Th cell populations. Deletion of Cic alleles in hematopoietic stem cells (Vav1-Cre-mediated knockout of Cic) causes more severe autoimmunity than that caused by the knockout of Cic in CD4⁺CD8⁺ double positive thymocytes (Cd4-Cre-mediated knockout of Cic). In this study, we compared splenic CD4⁺ T cell activation and proliferation between whole immune cell-specific Cic-null (Cic^f/f;Vav1-Cre) and T cell-specific Cic-null (Cic^f/f;Cd4-Cre) mice. Hyperactivation and hyperproliferation of CD4⁺ T cells were more apparent in Cic^f/f;Vav1-Cre mice than in Cic^f/f;Cd4-Cre mice. Cic^f/f;Vav1-Cre CD4⁺ T cells more rapidly proliferated and secreted larger amounts of IL-2 upon TCR stimulation than did Cic^f/f;Cd4-Cre CD4⁺ T cells, while the TCR stimulation-induced activation of the TCR signaling cascade and calcium flux were comparable between them. Mixed wild-type and Cic^f/f;Vav1-Cre bone marrow chimeras also exhibited more apparent hyperactivation and hyperproliferation of Cic-deficient CD4⁺ T cells than did mixed wild-type and Cic^f/f;Cd4-Cre bone marrow chimeras. Taken together, our data demonstrate that CIC deficiency at the beginning of T cell development endows peripheral CD4⁺ T cells with enhanced T cell activation and proliferative capability.