• 제목/요약/키워드: cell response

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Drosophila melanogaster: a Model for the Study of DNA Damage Checkpoint Response

  • Song, Young-Han
    • Molecules and Cells
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    • 제19권2호
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    • pp.167-179
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    • 2005
  • The cells of metazoans respond to DNA damage by either arresting their cell cycle in order to repair the DNA, or by undergoing apoptosis. This response is highly conserved across species, and many of the genes involved in this DNA damage response have been shown to be inactivated in human cancers. This suggests the importance of DNA damage response with regard to the prevention of cancer. The DNA damage checkpoint responses vary greatly depending on the developmental context, cell type, gene expression profile, and the degree and nature of the DNA lesions. More valuable information can be obtained from studies utilizing whole organisms in which the molecular basis of development has been well established, such as Drosophila. Since the discovery of the Drosophila p53 orthologue, various aspects of DNA damage responses have been studied in Drosophila. In this review, I will summarize the current knowledge on the DNA damage checkpoint response in Drosophila. With the ease of genetic, cellular, and cytological approaches, Drosophila will become an increasingly valuable model organism for the study of mechanisms inherent to cancer formation associated with defects in the DNA damage pathway.

A Study on Fast Response Time for Twisted Nematic Liquid Crystal Display

  • Lee, Kyung-Jun;Jeon, Yong-Je;Hwang, Jeoung-Yeon;Seo, Dae-Shik;Jeon, Youn-Hak;Nam, Sang-Hee
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 춘계학술대회 논문집 디스플레이 광소자 분야
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    • pp.121-123
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    • 2002
  • Fast response characteristics of twisted nematic liquid crystal display (TN-LCD) cell with different nematic liquid crystals (NLCs) and cell gap on a rubbed polyimide (PI) surface were studied. High transmittance and fast response time of the TN-LCD on the rubbed PI surface were achieved by using high birefringence ($\Delta$ n) and low cell gap. It is considered that the transmittance and response time of the TN-LCD on the rubbed PI surface decreased as $\Delta$ nd decrease.

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수소연료전지 자동차의 긴급대응 가이드 분석 (The Analysis of Emergency Response Guide for Hydrogen Fuel Cell Vehicle)

  • 이광주;이종태;용기중
    • 한국수소및신에너지학회논문집
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    • 제23권2호
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    • pp.156-161
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    • 2012
  • In case of commercializing of the hydrogen fuel cell vehicle, the suitable emergency response guide is necessary to prepare an accident. In order to suggest the suitable guide for the domestic affairs, the existing external guide about GM, Ford, Honda, and Hyundai was reviewed. The emergency response guides in CAFCP and main FC vehicle makers were included in the analysis. As the results, it was found that the design and make of vehicle for the domestic user are demanded in the emergency response and the guide is made with the shut-down manual picked out for the rescuer and repair man as well as user.

A Dual-Cell-Gap Transflective Liquid Crystal Display with Identical Response Time in Transmissive and Reflective Regions

  • Zhang, Jian-De;Wang, Qiong-Hua;Li, Da-Hai;Yan, Jin-Ren
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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    • pp.87-90
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    • 2009
  • A dual-cell-gap transflective liquid crystal display (TR-LCD) with identical response time in the transmissive and reflective regions is demonstrated. In the transmissive region, strong anchoring energy condition is used to decrease the response time, while in the reflective region weak anchoring energy condition is used to increase the response time. The simulated dual-cell-gap TR-LCD has good performances.

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유전율 이방성이 양인 액정을 이용한 고속응답용 FFS 모드 (Study on the Fringe Field Switching (FFS) Mode with the Positive Dielectric Anisotropy for the Fast Response Time)

  • 김미숙;김향율;송성훈;양석만;이성규;임영진;이승희
    • 한국전기전자재료학회논문지
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    • 제17권7호
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    • pp.754-759
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    • 2004
  • We have studied the fringe field switching (FFS) mode with the positive dielectric anisotropy for the fast response time. The factors such as the physical properties of the LC, the cell gap, and the rubbing angle were critical for the fast response time of the FFS mode. The response time became 10 ms faster when the rotational viscosity of the new LC is 20 mPa.s lower than the conventional LC. When the cell gap changed from 3.6 ${\mu}{\textrm}{m}$ to 3.0 ${\mu}{\textrm}{m}$, it was possible to achieve the total response time and response times associated with grey-to-grey transitions under 16 ms. And the response times including grey-to-grey transitions become fast as the rubbing angle decreases.

상아질 접착 지각과민 처치제에 대한 치수반응에 관한 연구 (A STUDY ON THE HUMAN PULPAL RESPONSE TO DENTIN BONDING DESENSITIZER)

  • 유희승;이성복;우이형;박남수;최부병
    • 대한치과보철학회지
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    • 제36권3호
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    • pp.483-495
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    • 1998
  • The purpose of this study was to evaluate the human pulpal response to Dentin Bonding Desensitizer. Class V cavities were prepared on the buccal surfaces of the first premolars and Dentin Bonding Desensitizer(ALL-BOND Desensitizer, Bisco, Inc. U.S.A.) was applicated in ten experimental teeth, or ZOE(PROPAC, GC Co. TOKYO, JAPAN) cement in eight control teeth and cavities were filled with light curing glass ionomer(Fuji II LC, GC Co., TOKYO, JAPAN). At 3-day and 25-day postoperative interval. pulpal response was observed and evaluated histologically with light microscope. The results were as follows. ; 1. At 3-day postoperative interval, the control teeth were grade 1 inflammatory cell response and grade 1 connective tissue response. 2. At 25-day postoperative interval, all control teeth were grade 1 inflammatory cell response and in three control teeth grade 1 connective tissue response were observed, and one teeth showed grade 2 connective tissue response. 3. At 3-day postoperative interval, the experimental teeth were grade 1 inflammatory cell response and grade 1 connective tissue response. Below the cavity, a few inflammatory cell(PMNs) in odontoblastic layer, increased blood vessels and pulpal cells were seen and this pulpal response was similar to control teeth. 4. At 25-day postoperative interval, in four experimental teeth grade 1 inflammatory cell response and grade 1 connective tissue response were observed, and one experimental teeth showed mild inflammatory response. 5. At 3-day and 25-day postoperative interval, no reparative dentin deposition was seen. 6. Both experimental and control group, pulpal response showed difference between 3 and 25-day of postoperative interval. In control teeth, increased predentin and pulpal cells were seen and in experimental teeth, congestion of blood vessels and increased pulpal cells were seen. In conclusion, the pulpal irritation due to this Dentin Bonding Desensitizer was not severe, and it was considered that the agent was not harmful to the human pulp.

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Effect of 65 kDa Buffalo Placental Protein on B-Cell Proliferation and Antibody Response

  • Deepthi, K.;Rajput, Y.S.
    • Asian-Australasian Journal of Animal Sciences
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    • 제15권3호
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    • pp.432-437
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    • 2002
  • Immunosuppressive potential of 65 kDa buffalo placental protein (bPP65) on B-cell proliferation in vitro and antibody response in vivo was evaluated. B-cell proliferation was estimated by measuring incorporation of tritiated thymidine in buffalo lymphocytes while primary antibody responses against phytohaemagglutinin (PHA) or keyhole limpet haemocyanin (KLH) were evaluated in mice. bPP65 suppressed proliferation of lipopolysaccharide (a B-cell specific mitogen)-stimulated buffalo lymphocytes in vitro indicating suppression of B-cells. This suppression was dose dependent over the protein concentration range $25-100 {\mu}g/ml$. Primary antibody responses in mice against PHA and KLH in presence of bPP65 were lower as compared to in its absence but these were not statistically significant. Amino acid composition data of bPP65 and BSA suggested that bPP65 is different from BSA.

Analysis of Immune Responses Against Nucleocapsid Protein of the Hantaan Virus Elicited by Virus Infection or DNA Vaccination

  • Woo Gyu-Jin;Chun Eun-Young;Kim Keun Hee;Kim Wankee
    • Journal of Microbiology
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    • 제43권6호
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    • pp.537-545
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    • 2005
  • Even though neutralizing antibodies against the Hantaan virus (HTNV) has been proven to be critical against viral infections, the cellular immune responses to HTNV are also assumed to be important for viral clearance. In this report, we have examined the cellular and humoral immune responses against the HTNV nucleocapsid protein (NP) elicited by virus infection or DNA vaccination. To examine the cellular immune response against HTNV NP, we used $H-2K^b$ restricted T-cell epitopes of NP. The NP-specific $CD8^+$ T cell response was analyzed using a $^{51}Cr-release$ assay, intracellular cytokine staining assay, enzyme-linked immunospot assay and tetramer binding assay in C57BL/6 mice infected with HTNV. Using these methods, we found that HTNV infection elicited a strong NP-specific $CD8^+$ T cell response at eight days after infection. We also found that several different methods to check the NP-specific $CD8^+$ T cell response showed a very high correlation among analysis. In the case of DNA vaccination by plasmid encoding nucleocapsid gene, the NP-specific antibody response was elicited $2\~4$ weeks after immunization and maximized at $6\~8$ weeks. NP-specific $CD8^+$ T cell response reached its peak 3 weeks after immunization. In a challenge test with the recombinant vaccinia virus expressing NP (rVV-HTNV-N), the rVV-HTNV-N titers in DNA vaccinated mice were decreased about 100-fold compared to the negative control mice.

Adiponectin에 의한 IL-2 증가 자연살해세포 독성의 조절 (IL-2-enhanced NK Cell Cytotoxicity is Regulated by Adiponectin from Hypothalamo-pituitary-adrenal Axis)

  • 김근영;양영
    • IMMUNE NETWORK
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    • 제6권1호
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    • pp.6-12
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    • 2006
  • Background: The Hypothalamo-Pituitary-Adrenal (HPA) axis is an important regulator for the body's stress response. As a primary stress responsive system, HPA-axis secretes various neurotransmitters, hormones, and cytokines, which regulates the immune system. Natural killer (NK) cell which is plays an important role in the innate immune response, is specially decreased their numbers and loose cytolytic activity in response to stress. However, the effect of HPA-axis secreted proteins on NK cell activity has not been defined. Herein, we studied the effect of adrenal secreted adiponectin on NK cell cytotoxicity. Adiponectin which is well-known metabolic control protein, plays important roles in various diseases, including hypertension, cardiovascular diseases, inflammatory disorders, and cancer. Methods: Signal sequence trap was used to find stress novel secretory protein from HP A-axis. Selected adiponectin was treated mouse mature primary NK cells and then examined the effect of adiponectin to NK cell cytotoxicity and cytokine expression level. Results: We found that adiponectin which is secreted from adrenal gland, suppress IL-2 induced NK cell cytotoxicity. And also investigated cytolytic cytokines are suppressed by adiponectin. Conclusion: These data suggest that adiponectin inhibites NK cell cytotoxicity via suppression of cytotoxicity related target gene.

Comparison of Metabolic and Anatomic Response to Chemotherapy Based on PERCIST and RECIST in Patients with Advanced Stage Non-small Cell Lung Cancer

  • Ordu, Cetin;Selcuk, Nalan A.;Akosman, Cengiz;Eren, Orhan Onder;Altunok, Elif C.;Toklu, Turkay;Oyan, Basak
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권1호
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    • pp.321-326
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    • 2015
  • Background: The aim of this study was to explore the prognostic role of metabolic response to chemotherapy, determined by FDG-PET, in patients with metastatic non-small-cell lung cancer (NSCLC). Materials and Methods: Thirty patients with metastatic NSCLC were analyzed for prognostic factors related to overall survival (OS) and progression free survival (PFS). Disease evaluation was conducted with FDG-PET/CT and contrast-enhanced CT prior to and at the end of first-line chemotherapy. Response evaluation of 19 of 30 patients was also performed after 2-3 cycles of chemotherapy. Morphological and metabolic responses were assessed according to RECIST and PERCIST, respectively. Results: The median OS and PFS were 11 months and 6.2 months, respectively. At the end of first-line chemotherapy, 10 patients achieved metabolic and anatomic responses. Of the 19 patients who had an interim response analysis after 2-3 cycles of chemotherapy, 3 achieved an anatomic response, while 9 achieved a metabolic response. In univariate analyses, favorable prognostic factors for OS were number of cycles of first-line chemotherapy, and achieving a response to chemotherapy at completion of therapy according to the PERCIST and RECIST. The OS of patients with a metabolic response after 2-3 cycles of chemotherapy was also significantly extended. Anatomic response at interim analysis did not predict OS, probably due to few patients with anatomic response. In multivariate analyses, metabolic response after completion of therapy was an independent prognostic factor for OS. Conclusions: Metabolic response is at least as effective as anatomic response in predicting survival. Metabolic response may be an earlier predictive factor for treatment response and OS in NSCLC patients.