• Title/Summary/Keyword: checkpoint

Search Result 269, Processing Time 0.022 seconds

Effects of the Water Extract from Albizzia julibrissin on Apoptosis and Cell Cycle Progression in the Human Leukemic Jurkat Cells (백혈병 세포주 Jurkat의 세포고사 유도 및 세포주기 억제에 미치는 합산피 추출물의 효과)

  • Park Young Jun;Jung Woo Cheal;Jeong Dae Young;Lee Yong Un;Lee In;Lee Key Sang;Jeon Byung Hun;Sung Kang Keyng;Moon Byung Soon
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.17 no.6
    • /
    • pp.1383-1392
    • /
    • 2003
  • Apoptosis is a morphologically and biochemically district form of cell death that occurs in many different cell types in a wide variety of organisms. Albizzia julibrissin belonging the family Leguminosae has been used for the treatment of contusion, sore throat, amnesia, and insomnia in oriental traditional medicine. This study investigates whether the water extract of A. julibrissin induce apoptotic cell death in Jurkat T-acute lymphoblastic leukemia (ALL) cells. Jurkat cells were increased inhibitions of cell viability in a concentration-dependent manner by A. julibrissin. This herbal medicine also caused apoptosis as measured by cell morphology and DNA fragmentation. The capability of A. julibrissin to induce apoptosis was associated with proteolytic cleavage of specific target proteins such as poly (ADP-ribose)polymerase (PARP) and beta-catenin proteins suggesting the possible involvement of caspases. Our result showed that Bcl-2 and Bax protein levels were not changed in all A. julibrissin-treated groups compared to control group. These results suggest that A. julibrissin-mediated apoptosis is independent with Bcl-2 related signaling pathway in this cells. The purpose of the present study is also to investigate the Effect of A. julibrissin on cell cycle progression. Our results showed that G1 checkpoint related gene products (cyclin D1, cyclin dependent kinase 4, retinoblastoma, E2F1) were decreased in their protein levels in a dose-dependent manners after treatment of the extract. These results indicate that the increase of apoptotic cell death by A. julibrissin may be due to the inhibition of cell cycle progression in wild type p53-lacking Jurkat cells.

Lazy Garbage Collection of Coordinated Checkpointing Protocol for Avoiding Sympathetic Rollback (동기적 검사점 기법에서 불필요한 복귀를 회피하기 위한 쓰레기 처리 기법)

  • Chung, Kwang-Sik;Yu, Heon-Chang;Lee, Won-Gyu;Lee, Seong-Hoon;Hwang, Chong-Sun
    • Journal of KIISE:Computer Systems and Theory
    • /
    • v.29 no.6
    • /
    • pp.331-339
    • /
    • 2002
  • This paper presents a garbage collection protocol for checkpoints and message logs which are staved on the stable storage or volatile storage for fault tolerancy. The previous works of garbage collections in coordinated checkpointing protocol delete all the checkpoints except for the last checkpoints on earth processes. But implemented in top of reliable communication protocol like as TCP/IP, rollback recovery protocol based on only last checkpoints makes sympathetic rollback. We show that the old checkpoints or message logs except for the last checkpoints have to be preserved in order to replay the lost message. And we define the conditions for garbage collection of checkpoints and message logs for lost messages and present the garbage collection algorithm for checkpoints and message logs in coordinated checkpointing protocol. Since the proposed algorithm uses process information for lost message piggybacked with messages, the additional messages for garbage collection is not required The proposed garbage collection algorithm makes 'the lazy garbage collectioneffect', because relying on the piggybacked checked checkpoint information in send/receive message. But 'the lazy garbage collection effect'does not break the consistency of the whole systems.

Garbage Collection Protocol of Fault Tolerance Information in Multi-agent Environments (멀티에이전트 환경에서 결함 포용 정보의 쓰레기 처리 기법)

  • 이대원;정광식;이화민;신상철;이영준;유헌창;이원규
    • Journal of KIISE:Computer Systems and Theory
    • /
    • v.31 no.3_4
    • /
    • pp.204-212
    • /
    • 2004
  • Existing distributed systems have higher probability of failures occurrence than stand-alone system, so many fault tolerant techniques have been developed. Because of insufficient storage resulting from the increased fault tolerance information stored, the performance of system has been degraded. To avoid performance degradation, it needs delete useless fault tolerance information. In this paper, we propose a garbage collection algorithm for fault tolerance information. And we define and design the garbage collection agent for garbage collection of fault tolerance information, the information agent for management of fault tolerant data, and the facilitator agent for communication between agents. Also, we propose the garbage collection algorithm using the garbage collection agent. For rollback recovery, we use independent checkpointing protocol and sender based pessimistic message logging protocol. In our proposed garbage collection algorithm, the garbage collection, information, and facilitator agent is created with process, and the information agent constructs domain knowledge with its checkpoints and non-determistic events. And the garbage collection agent decides garbage collection time, and it deletes useless fault tolerance information in cooperation with the information and facilitator agent. For propriety of proposed garbage collection technique using agents, we compare domain knowledge of system that performs garbage collection after rollback recovery and domain knowledge of system that doesn't perform garbage collection.

The Overexpression of p53 in Head and Neck Squamous Cell Carcinoma as Prognostic Marker (두경부 편평 세포암에서 예후인자로서의 p53 발현)

  • Jeong Seung-Won;Lee Hyung-Seok;Park Chul-Won;Park Yong-Wook;Park Chan-Keum;Jang Se-Jin;Tae Kyung
    • Korean Journal of Head & Neck Oncology
    • /
    • v.17 no.2
    • /
    • pp.169-173
    • /
    • 2001
  • Objectives: The p53 tumor suppressor gene encodes a nuclear transcription factor that is critical regulator of cell growth and proliferation through its action in cell-cycle checkpoint control. The wide variety of stressful stmuli which include DNA damage, hypoxia, heat shock, metabolic changes activate the p53 protein, which in turn drives a series of events that culminate either in cell cycle arrest or apoptosis. Mutations of the p53 gene is the most common genetic alteration in human cancer. This gene is altered in approximately 40-60% of head and neck cancers. Whereas the wild-type form of the p53 protein plays a central role in cell-cycle control in response to DNA damage, most of the mutant forms are unable to do so. The high levels of p53 protein expression in tissues are related to the increased cellular proliferative activity and may be associated with the poor clinical outcome. To determine whether the expression of the p53 protein has prognostic significance and is associated with patterns of treatment failure in head and neck squamous cell carcinoma (HNSCC), We analyzed p53 overexpression in 40 cases of HNSCC. Materials and Methods: Immunohistochemical analysis with a monoclonal antibody (DO7) specific for p53 protein was used to detect expression of the protein in formalin-fixed, paraffin-embedded tumor samples from 40 HNSCC. We evaluated p53 protein expression and analyzed the relationship between the p53 overexpression and age, sex, primary tumor site, stage, survival rate, recurrence. All reported P values resulted from two-sided statistical tests. Results: Overexpression of p53 was detected in 20 cases(50%) among 40 cases of HNSCC. The p53 overexpression was not associated with age, sex, primary tumor site, stage, recurrence and survival rate. Conclusions: In our results, p53 was not significant prognostic factor in HNSCC. Based on many previous studies, It is evident that p53 has a certain role in tumorigenesis of HNSCC. So, the further study is needed to evaluate the prognostic significance of p53 in HNSCC.

  • PDF

PD-L1 expression correlated with p53 expression in oral squamous cell carcinoma

  • Tojyo, Itaru;Shintani, Yukari;Nakanishi, Takashi;Okamoto, Kenjiro;Hiraishi, Yukihiro;Fujita, Shigeyuki;Enaka, Mayu;Sato, Fuyuki;Muragaki, Yasuteru
    • Maxillofacial Plastic and Reconstructive Surgery
    • /
    • v.41
    • /
    • pp.56.1-56.6
    • /
    • 2019
  • Background: Programmed cell death ligand 1 (PD-L1) is an immune checkpoint molecule that attenuates the immune response. PD-L1 contributes to failed antitumor immunity; thereby, blockade of PD-L1 with monoclonal antibody enhances the immune response. Recently, it was reported that PD-L1 was regulated by protein 53 (p53). Besides, cytokeratin 17 (CK17) is thought to be a diagnostic marker of oral squamous cell carcinoma (OSCC). Our aim was to evaluate the correlation between the immunohistochemical expression of PD-L1, p53 and CK17 with clinicopathological characteristics and disease-specific survival in patients with OSCC. Methods: A total of 48 patients with OSCC were included in this study. Immunohistochemical staining was performed to evaluate the correlation among the expressions of PD-L1, p53 and CK17, and furthermore the correlation among various clinicopathological factors, PD-L1, p53 and CK17. Results: The positive rate of p53, CK17, PD-L1 (tumor cells) and PD-L1 (tumor-infiltrating lymphocytes) was 63.2%, 91.7%, 48.9% and 57.1%. A statistically significant correlation between p53 expression and T stage and TNM stage (p = 0.049, p = 0.03, respectively) was observed. Also, a statistically significant correlation between p53 and PD-L1 (TCs) expression (p = 0.0009) was observed. Five-year disease-specific survival rate was not significantly correlated with gender, TNM stage, p53 expression, PD-L1 expression and CK17 expression. Conclusion: The expression of p53 and PD-L1 shows significantly positive correlation in oral squamous cell carcinoma in tumor cells. Also, a significant correlation between p53 expression and T stage and TNM stage was observed. No other significant correlation between PD-L1 staining or CK17 and clinical or pathologic characteristics was identified.

Alkaloids from Beach Spider Lily (Hymenocallis littoralis) Induce Apoptosis of HepG-2 Cells by the Fas-signaling Pathway

  • Ji, Yu-Bin;Chen, Ning;Zhu, Hong-Wei;Ling, Na;Li, Wen-Lan;Song, Dong-Xue;Gao, Shi-Yong;Zhang, Wang-Cheng;Ma, Nan-Nan
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.15 no.21
    • /
    • pp.9319-9325
    • /
    • 2014
  • Alkaloids are the most extensively featured compounds of natural anti-tumor herbs, which have attracted much attention in pharmaceutical research. In our previous studies, a mixture of major three alkaloid components (5, 6-dihydrobicolorine, 7-deoxy-trans-dihydronarciclasine, littoraline) from Hymenocallis littoralis were extracted, analyzed and designated as AHL. In this paper, AHL extracts were added to human liver hepatocellular cells HepG-2, human gastric cancer cell SGC-7901, human breast adenocarcinoma cell MCF-7 and human umbilical vein endothelial cell EVC-304, to screen one or more AHL-sensitive tumor cell. Among these cells, HepG-2 was the most sensitive to AHL treatment, a very low dose ($0.8{\mu}g/ml$) significantly inhibiting proliferation. The non-tumor cell EVC-304, however, was not apparently affected. Effect of AHL on HepG-2 cells was then explored. We found that the AHL could cause HepG-2 cycle arrest at G2/M checkpoint, induce apoptosis, and interrupt polymerization of microtubules. In addition, expression of two cell cycle-regulated proteins, CyclinB1 and CDK1, was up-regulated upon AHL treatment. Up-regulation of the Fas, Fas ligand, Caspase-8 and Caspase-3 was observed as well, which might imply roles for the Fas/FsaL signaling pathway in the AHL-induced apoptosis of HepG-2 cells.

Tumour Suppressive Effects of WEE1 Gene Silencing in Breast Cancer Cells

  • Ghiasi, Naghmeh;Habibagahi, Mojtaba;Rosli, Rozita;Ghaderi, Abbas;Yusoff, Khatijah;Hosseini, Ahmad;Abdullah, Syahrilnizam;Jaberipour, Mansooreh
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.14 no.11
    • /
    • pp.6605-6611
    • /
    • 2013
  • Background: WEE1 is a G2/M checkpoint regulator protein. Various studies have indicated that WEE1 could be a good target for cancer therapy. The main aim of this study was to asssess the tumor suppressive potential of WEE1 silencing in two different breast cancer cell lines, MCF7 which carries the wild-type p53 and MDA-MB468 which contains a mutant type. Materials and Methods: After WEE1 knockdown with specific shRNAs downstream effects on cell viability and cell cycle progression were determined using MTT and flow cytometry analyses, respectively. Real-time PCR and Western blotting were conducted to assess the effect of WEE1 inhibition on the expression of apoptotic (p53) and anti-apoptotic (Bcl2) factors and also a growth marker (VEGF). Results: The results showed that WEE1 inhibition could cause a significant decrease in the viability of both MCF7 and MDA-MB-468 breast cancer cell lines by more than 50%. Interestingly, DNA content assays showed a significant increase in apoptotic cells following WEE1 silencing. WEE1 inhibition also induced upregulation of the apoptotic marker, p53, in breast cancer cells. A significant decrease in the expression of VEGF and Bcl-2 was observed following WEE1 inhibition in both cell lines. Conclusions: In concordance with previous studies, our data showed that WEE1 inhibition could induce G2 arrest abrogation and consequent cell death in breast cancer cells. Moreover, in this study, the observed interactions between the pro- and anti-apoptotic proteins and decrease in the angiogenesis marker expression confirm the susceptibility to apoptosis and validate the tumor suppressive effect of WEE1 inhibition in breast cancer cells. Interestingly, the levels of the sensitivity to WEE1 silencing in breast cancer cells, MCF7 and MDA-MB468, seem to be in concordance with the level of p53 expression.

Proteomic Analysis and the Antimetastatic Effect of N-(4methyl)phenyl-O-(4-methoxy) phenyl-thionocarbamate-Induced Apoptosis in Human Melanoma SK-MEL-28 cells

  • Choi Su-La;Choi Yun-Sil;Kim Young-Kwan;Sung Nack-Do;Kho Chang-Won;Park Byong-Chul;Kim Eun-Mi;Lee Jung-Hyung;Kim Kyung-Mee;Kim Min-Yung;Myung Pyung-Keun
    • Archives of Pharmacal Research
    • /
    • v.29 no.3
    • /
    • pp.224-234
    • /
    • 2006
  • We employed human SK-MEL-28 cells as a model system to identify cellular proteins that accompany N-(4-methyl)phenyl-O-(4-methoxy)phenyl-thionocarbamate (MMTC)-induced apoptosis based on a proteomic approach. Cell viability tests revealed that SK-MEL-28 skin cancer cells underwent more cell death than normal HaCaT cells in a dose-dependent manner after treatment with MMTC. Two-dimensional electrophoresis in conjunction with matrixassisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry analysis or computer matching with a protein database further revealed that the MMTC-induced apoptosis is accompanied by increased levels of caspase-1, checkpoint suppressor-1, caspase-4, NF-kB inhibitor, AP-2, c-Jun-N-terminal kinase, melanoma inhibitor, granzyme K, G1/S specific cyclin D3, cystein rich protein, Ras-related protein Rab-37 or Ras-related protein Rab-13, and reduced levels of EMS (oncogene), ATP synthase, tyrosine-phosphatase, Cdc25c, 14-3-3 protein or specific structure of nuclear receptor. The migration suppressing effect of MMTC on SK-MEL-28 cell was tested. MMTC suppressed the metastasis of SK-MEL-8 cells. It was also identified that MMTC had little angiogenic effect because it did not suppress the proliferation of HUVEC cell line. These results suggest that MMTC is a novel chemotherapeutic and metastatic agents against the SK-MEL-28 human melanoma cell line.

Construction of 3D Spatial Information of Vertical Structure by Combining UAS and Terrestrial LiDAR (UAS와 지상 LiDAR 조합에 의한 수직 구조물의 3차원 공간정보 구축)

  • Kang, Joon-Oh;Lee, Yong-Chang
    • Journal of Cadastre & Land InformatiX
    • /
    • v.49 no.2
    • /
    • pp.57-66
    • /
    • 2019
  • Recently, as a part of the production of spatial information by smart cities, three-dimensional reproduction of structures for reverse engineering has been attracting attention. In particular, terrestrial LiDAR is mainly used for 3D reproduction of structures, and 3D reproduction research by UAS has been actively conducted. However, both technologies produce blind spots due to the shooting angle. This study deals with vertical structures. 3D model implemented through SfM-based image analysis technology using UAS and reproducibility and effectiveness of 3D models by terrestrial LiDAR-based laser scanning are examined. In addition, two 3D models are merged and reviewed to complement the blind spot. For this purpose, UAS based image is acquired for artificial rock wall, VCP and check point are set through GNSS equipment and total station, and 3D model of structure is reproduced by using SfM based image analysis technology. In addition, Through 3D LiDAR scanning, the 3D point cloud of the structure was acquired, and the accuracy of reproduction and completeness of the 3D model based on the checkpoint were compared and reviewed with the UAS-based image analysis results. In particular, accuracy and realistic reproducibility were verified through a combination of point cloud constructed from UAS and terrestrial LiDAR. The results show that UAS - based image analysis is superior in accuracy and 3D model completeness and It is confirmed that accuracy improves with the combination of two methods. As a result of this study, it is expected that UAS and terrestrial LiDAR laser scanning combination can complement and reproduce precise three-dimensional model of vertical structure, so it can be effectively used for spatial information construction, safety diagnosis and maintenance management.

Accuracy Evaluation of LiDAR Measurement in Forest Area (산림지역에서 LiDAR 측량의 정확도 평가)

  • Lee, Sang-Hoon;Lee, Byoung-Kil;Kim, Jin-Kwang;Kim, Chang-Jae
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
    • /
    • v.27 no.5
    • /
    • pp.545-553
    • /
    • 2009
  • Digital Elevation Models (DEM) is widely used in establishing the topographic profile in nation spatial information. Aerial Light Detection And Ranging (LiDAR) system is one of the well-known means to produce DEM. The system has fast data acquisition procedures and less weather-dependent restrictions compared to photogrammetric approaches. In this regards, LiDAR has been widely utilized and accepted in the process of nation spatial information generation due to its sufficient positional accuracy. However, the investigation of the accuracy of aerial LiDAR data over the area of forestation with various kinds of vegetations has been barely implemented in Korea. Hence, this research focuses on the investigation of the accuracy of aerial LiDAR data over the area of forestation and the evaluation of the acquired accuracy according to the characteristics of the vegetations. The study areas include land with shrubs and its adjacent forest area with mixed tree species. The spots for the investigation have been selected to be well-distributed over the whole study areas and their coordinates are surveyed by Global Positioning Systems (GPS). Then, the surveyed information and aerial LiDAR data have been compared with each other and the result accuracy has been evaluated. Conclusively, it is recommended that LiDAR data collection to be conducted after defoliation period, especially over the areas with broadleaf trees due to the possibility of significant outliers.