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Adequate concentration of B cell leukemia/lymphoma 3 (Bcl3) is required for pluripotency and self-renewal of mouse embryonic stem cells via downregulation of Nanog transcription

  • Kang, Songhwa;Yun, Jisoo;Kim, Da Yeon;Jung, Seok Yun;Kim, Yeon Ju;Park, Ji Hye;Ji, Seung Taek;Jang, Woong Bi;Ha, Jongseong;Kim, Jae Ho;Baek, Sang Hong;Kwon, Sang-Mo
    • BMB Reports
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    • v.51 no.2
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    • pp.92-97
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    • 2018
  • B cell leukemia/lymphoma 3 (Bcl3) plays a pivotal role in immune homeostasis, cellular proliferation, and cell survival, as a co-activator or co-repressor of transcription of the $NF-{\kappa}B$ family. Recently, it was reported that Bcl3 positively regulates pluripotency genes, including Oct4, in mouse embryonic stem cells (mESCs). However, the role of Bcl3 in the maintenance of pluripotency and self-renewal activity is not fully established. Here, we report the dynamic regulation of the proliferation, pluripotency, and self-renewal of mESCs by Bcl3 via an influence on Nanog transcriptional activity. Bcl3 expression is predominantly observed in immature mESCs, but significantly decreased during cell differentiation by LIF depletion and in mESC-derived EBs. Importantly, the knockdown of Bcl3 resulted in the loss of self-renewal ability and decreased cell proliferation. Similarly, the ectopic expression of Bcl3 also resulted in a significant reduction of proliferation, and the self-renewal of mESCs was demonstrated by alkaline phosphatase staining and clonogenic single cell-derived colony assay. We further examined that Bcl3-mediated regulation of Nanog transcriptional activity in mESCs, which indicated that Bcl3 acts as a transcriptional repressor of Nanog expression in mESCs. In conclusion, we demonstrated that a sufficient concentration of Bcl3 in mESCs plays a critical role in the maintenance of pluripotency and the self-renewal of mESCs via the regulation of Nanog transcriptional activity.

Performance of Homologous and Heterologous Prime-Boost Immunization Regimens of Recombinant Adenovirus and Modified Vaccinia Virus Ankara Expressing an Ag85B-TB10.4 Fusion Protein against Mycobacterium tuberculosis

  • Kou, Yiming;Wan, Mingming;Shi, Wei;Liu, Jie;Zhao, Zhilei;Xu, Yongqing;Wei, Wei;Sun, Bo;Gao, Feng;Cai, Linjun;Jiang, Chunlai
    • Journal of Microbiology and Biotechnology
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    • v.28 no.6
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    • pp.1022-1029
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    • 2018
  • Tuberculosis (TB) remains a serious health issue around the word. Adenovirus (Ad)-based vaccine and modified vaccinia virus Ankara (MVA)-based vaccine have emerged as two of the most promising immunization candidates over the past few years. However, the performance of the homologous and heterologous prime-boost immunization regimens of these two viral vector-based vaccines remains unclear. In the present study, we constructed recombinant Ad and MVA expressing an Ag85B-TB10.4 fusion protein (AdH4 and MVAH4) and evaluated the impact of their different immunization regimens on the humoral and cellular immune responses. We found that the viral vector-based vaccines could generate significantly higher levels of antigen-specific antibodies, $IFN-{\gamma}$-producing splenocytes, $CD69^+CD8^+$ T cells, and $IFN-{\gamma}$ secretion when compared with bacillus Calmette-$Gu{\acute{e}}rin$ (BCG) in a mouse model. AdH4-containing immunization regimens (AdH4-AdH4, AdH4-MVAH4, and MVAH4-AdH4) induced significantly stronger antibody responses, much more $IFN-{\gamma}$-producing splenocytes and $CD69^+CD8^+$ T cells, and higher levels of $IFN-{\gamma}$ secretion when compared with the MVAH4-MVAH4 immunization regimen. The number of $IFN-{\gamma}$-producing splenocytes sensitive to $CD8^+$ T-cell restricted peptides of Ag85B (9-1p and 9-2p) and Th1-related cytokines ($IFN-{\gamma}$ and $TNF-{\alpha}$) in the AdH4-MVAH4 heterologous prime-boost regimen immunization group was significantly higher than that in the other viral vector-based vaccine- and BCG-immunized groups, respectively. These results indicate that an immunization regimen involving AdH4 may have a higher capacity to induce humoral and cellular immune responses against TB in mice than that by regimens containing BCG or MVAH4 alone, and the AdH4-MVAH4 prime-boost regimen may generate an ideal protective effect.

Tokamak plasma disruption precursor onset time study based on semi-supervised anomaly detection

  • X.K. Ai;W. Zheng;M. Zhang;D.L. Chen;C.S. Shen;B.H. Guo;B.J. Xiao;Y. Zhong;N.C. Wang;Z.J. Yang;Z.P. Chen;Z.Y. Chen;Y.H. Ding;Y. Pan
    • Nuclear Engineering and Technology
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    • v.56 no.4
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    • pp.1501-1512
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    • 2024
  • Plasma disruption in tokamak experiments is a challenging issue that causes damage to the device. Reliable prediction methods are needed, but the lack of full understanding of plasma disruption limits the effectiveness of physics-driven methods. Data-driven methods based on supervised learning are commonly used, and they rely on labelled training data. However, manual labelling of disruption precursors is a time-consuming and challenging task, as some precursors are difficult to accurately identify. The mainstream labelling methods assume that the precursor onset occurs at a fixed time before disruption, which leads to mislabeled samples and suboptimal prediction performance. In this paper, we present disruption prediction methods based on anomaly detection to address these issues, demonstrating good prediction performance on J-TEXT and EAST. By evaluating precursor onset times using different anomaly detection algorithms, it is found that labelling methods can be improved since the onset times of different shots are not necessarily the same. The study optimizes precursor labelling using the onset times inferred by the anomaly detection predictor and test the optimized labels on supervised learning disruption predictors. The results on J-TEXT and EAST show that the models trained on the optimized labels outperform those trained on fixed onset time labels.

PC-766B' and PC-766B, 16-Membered Maerolide Angiogenesis Inhibitors Produced by Nocardia sp. RK97-56

  • Ko, Hack-Ryong;Kakeya, Hideaki;Yoshida, Arika;Onose, Rie;Ueki, Masashi;Muroi, Makoto;Takatsuki, Akira;Matsuzaki, Hiroshi;Osada, Hiroyuki
    • Journal of Microbiology and Biotechnology
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    • v.12 no.5
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    • pp.829-833
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    • 2002
  • Angiogenesis is an essential event in a variety of physiological and pathological processes. Therefore, effective inhibition of this event is a promising strategy for treating angiogenesis-related diseases, including cancer. The current study investigated two unique bafilomycin-type macrolide inhibitors of angiogenesls, PC-766B' (1) and PC-766B (2). The strain RK97-56 which produced the inhibitors was identified as Nocardia sp. by chemotaxonomic analyses, and the purification of the inhibitors was guided by their anti-angiogenic activities. PC-766B' (1) and PC-766B (2) exhibited potent inhibitory activities towards endothelial cell migration stimulated by the vascular endothelial growth factor (VEGF).

Affordable method of video recording for ecologists and citizen-science participants

  • Yang, Eunjeong;Lee, Keesan;Ha, Jung-moon;Kim, Woojoo;Song, Ho-Kyung;Hwang, Injae;Lee, Sang-im;Jablonski, Piotr G.
    • Journal of Ecology and Environment
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    • v.42 no.2
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    • pp.85-89
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    • 2018
  • Observations and video documentation of interactions between animals living in dens, cavities, and other enclosed spaces are difficult, but they play an important role in field biology, ecology, and conservation. For example, bird parents visiting nests and feeding their nestlings may provide crucial information for testing of ecological hypotheses and may easily attract attention of participants of citizen-science ecological and conservation projects. Because of the nest concealment of cavity-nesting birds, their behaviors in the nest can only be studied by using video surveillance. Professional wildlife surveillance systems are extremely expensive. Here, we describe an inexpensive video setup that can be constructed with relatively little effort and is more affordable than any previously described system. We anticipate that the relatively low cost of about 250 USD for a battery-operated system is an important feature for citizen-science type of projects and for applications in heavily populated areas where the potential for theft and vandalism may be high. Based on our experiences, we provide methodological advice on practical aspects of using this system in the field for ecological research on birds. We highlight the low cost, easiness of construction, and potential availability to a large number of observers taking part in wildlife monitoring projects, and we offer technical help to participants of such research projects.

Cloning and Characterization of Filamentous Fungal S-Nitrosoglutathione Reductase from Aspergillus nidulans

  • Zhou, Yao;Zhou, Shengmin;Yu, Haijun;Li, Jingyi;Xia, Yang;Li, Baoyi;Wang, Xiaoli;Wang, Ping
    • Journal of Microbiology and Biotechnology
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    • v.26 no.5
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    • pp.928-937
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    • 2016
  • S-Nitrosoglutathione reductase (GSNOR) metabolizes S-nitrosoglutathione (GSNO) and has been shown to play important roles in regulating cellular signaling and formulating host defense by modulating intracellular nitric oxide levels. The enzyme has been found in bacterial, yeast, mushroom, plant, and mammalian cells. However, to date, there is still no evidence of its occurrence in filamentous fungi. In this study, we cloned and investigated a GSNOR-like enzyme from the filamentous fungus Aspergillus nidulans. The enzyme occurred in native form as a homodimer and exhibited low thermal stability. GSNO was an ideal substrate for the enzyme. The apparent Km and kcat values were 0.55 mM and 34,100 min-1, respectively. Substrate binding sites and catalytic center amino acid residues based on those from known GSNORs were conserved in this enzyme, and the corresponding roles were verified using site-directed mutagenesis. Therefore, we demonstrated the presence of GSNOR in a filamentous fungus for the first time.

FADD Phosphorylation Modulates Blood Glucose Levels by Decreasing the Expression of InsulinDegrading Enzyme

  • Lin, Yan;Liu, Jia;Chen, Jia;Yao, Chun;Yang, Yunwen;Wang, Jie;Zhuang, Hongqin;Hua, Zi-Chun
    • Molecules and Cells
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    • v.43 no.4
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    • pp.373-383
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    • 2020
  • Our previous study revealed a novel role of Fas-associated death domain-containing protein (FADD) in islet development and insulin secretion. Insulin-degrading enzyme (IDE) is a zinc metalloprotease that selectively degrades biologically important substrates associated with type 2 diabetes (T2DM). The current study was designed to investigate the effect of FADD phosphorylation on IDE. We found that the mRNA and protein levels of IDE were significantly downregulated in FADD-D mouse livers compared with control mice. Quantitative real-time polymerase chain reaction analysis showed that FADD regulates the expression of IDE at the transcriptional level without affecting the stability of the mRNA in HepG2 cells. Following treatment with cycloheximide, the IDE protein degradation rate was found to be increased in both FADD-D primary hepatocytes and FADD-knockdown HepG2 cells. Additionally, IDE expression levels were reduced in insulin-stimulated primary hepatocytes from FADD-D mice compared to those from control mice. Moreover, FADD phosphorylation promotes nuclear translocation of FoxO1, thus inhibiting the transcriptional activity of the IDE promoter. Together, these findings imply a novel role of FADD in the reduction of protein stability and expression levels of IDE.

Emodin-Provoked Oxidative Stress Induces Apoptosis in Human Colon Cancer HCT116 Cells through a p53-Mitochondrial Apoptotic Pathway

  • Xie, Mei-Juan;Ma, Yi-Hua;Miao, Lin;Wang, Yan;Wang, Hai-Zhen;Xing, Ying-Ying;Xi, Tao;Lu, Yuan-Yuan
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.13
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    • pp.5201-5205
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    • 2014
  • Emodin, a natural anthraquinone isolated from the traditional Chinese medicine Radix rhizoma Rhei, can induce apoptosis in many kinds of cancer cells. This study demonstrated that emodin induces apoptosis in human colon cancer HCT116 cells by provoking oxidative stress, which subsequently triggers a p53-mitochondrial apoptotic pathway. Emodin induced mitochondrial transmembrane potential loss, increase in Bax and decrease in Bcl-2 expression and mitochondrial translocation and release of cytochrome c to cytosol in HCT116 cells. In response to emodin-treatment, ROS increased rapidly, and subsequently p53 was overexpressed. Pretreatment with the antioxidant NAC diminished apoptosis and p53 overexpression induced by emodin. Transfecting p53 siRNA also attenuated apoptosis induced by emodin, Bax expression and mitochondrial translocation being reduced compared to treatment with emodin alone. Taken together, these results indicate that ROS is a trigger of emodin-induced apoptosis in HCT116 cells, and p53 expression increases under oxidative stress, leading to Bax-mediated mitochondrial apoptosis.

GTP Binding Is Required for SEPT12 to Form Filaments and to Interact with SEPT11

  • Ding, Xiangming;Yu, Wenbo;Liu, Ming;Shen, ShuQing;Chen, Fang;Cao, Lihuan;Wan, Bo;Yu, Long
    • Molecules and Cells
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    • v.25 no.3
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    • pp.385-389
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    • 2008
  • Septins are a family of filament-forming GTP-binding proteins involved in a variety of cellular process such as cytokinesis, exocytosis, and membrane dynamics. Here we report the biochemical and immunocytochemical characterization of a recently identified mammalian septin, SEPT12. SEPT12 binds GTP in vitro, and a mutation (Gly56 to Asn) in the GTP-binding motif abolished binding. Immunocytochemical analysis revealed that wild-type SEPT12 formed filamentous structures when transiently expressed in Hela cells whereas $SEPT12^{G56A}$ generated large aggregates. In addition, wild-type SEPT12 failed to form filaments when coexpressed with $SEPT12^{G56A}$. We also observed that GTP-binding by SEPT12 is required for interaction with SEPT11 but not with itself.

A Case of Huge Pulmonary Blastoma With Multiorgan Invasion (다기관 침범을 동반한 거대 폐 모세포종)

  • Lee, Tae Hwan;Lee, Ka Young;Kim, So Ri;Min, Kyung Hun;Park, Seoung Ju;Lee, Heung Bum;Rhee, Yang Keun;Lee, Yong Chul
    • Tuberculosis and Respiratory Diseases
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    • v.62 no.2
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    • pp.149-153
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    • 2007
  • A pulmonary blastoma is a rare malignant tumor of the lung that is composed of epithelial and mesenchymal elements and resembles the structure of an embryonic lung. Pulmonary blastomas have a very poor prognosis and make up 0.25 to 0.5 percent of all primary malignant lung tumors. A pulmonary blastoma usually manifests as a solitary parenchymal mass or nodule and multiple subpleural mass with effusion on chest X-ray and computed tomography. We encountered a very rare case of pulmonary blastoma in a 52 years old male. He complained of abdominal pain, fullness, and dyspnea. The radiology examination revealed a huge lung mass invading the mediastinum, heart, diaphragm, and liver. The percutaneous needle biopsies were performed, and this tumor was diagnosed as a pulmonary blastoma. We report a biopsy confirmed case of a huge pulmonary blastoma invading multiple organs.