• Title/Summary/Keyword: stable cells

Search Result 967, Processing Time 0.027 seconds

Hippo-YAP/TAZ signaling in angiogenesis

  • Park, Jeong Ae;Kwon, Young-Guen
    • BMB Reports
    • /
    • v.51 no.3
    • /
    • pp.157-162
    • /
    • 2018
  • Angiogenesis is a complex, multistep process involving dynamic changes in endothelial cell (EC) shapes and behaviors, especially in specialized cell types such as tip cells (with active filopodial extensions), stalk cells (with less motility) and phalanx cells (with stable junction connections). The Hippo-Yes-associated protein (YAP)/ transcription activator with PDZ binding motif (TAZ) signaling plays a critical role in development, regeneration and organ size by regulating cell-cell contact and actin cytoskeleton dynamics. Recently, with the finding that YAP is expressed in the front edge of the developing retinal vessels, Hippo-YAP/TAZ signaling has emerged as a new pathway for blood vessel development. Intriguingly, the LATS1/2-mediated angiomotin (AMOT) family and YAP/TAZ activities contribute to EC shapes and behaviors by spatiotemporally modulating actin cytoskeleton dynamics and EC junction stability. Herein, we summarize the recent understanding of the role of Hippo-YAP/TAZ signaling in the processes of EC sprouting and junction maturation in angiogenesis.

Catalytic Effects of Barium Carbonate on the Anodic Performance of Solid Oxide Fuel Cells

  • Yoon, Sung-Eun;Ahn, Jae-Yeong;Park, Jong-Sung
    • Journal of the Korean Ceramic Society
    • /
    • v.52 no.5
    • /
    • pp.350-355
    • /
    • 2015
  • To develop ceramic composite anodes of solid oxide fuel cells without metal catalysts, a small amount of barium carbonate was added to an $(La_{0.8}Sr_{0.2})(Cr_{0.5}Mn_{0.5})O_3(LSCM)$ - YSZ ceramic composite anode and its catalytic effects on the electrode performance were investigated. A barium precursor solution with citric acid was used to synthesize the barium carbonate during ignition, while a barium precursor solution without citric acid was used to create hydrated barium hydroxide. The addition of barium carbonate to the ceramic composite anode caused stable fuel cell performance at 1073 K; this performance was higher than that of a fuel cell with $CeO_2$ catalyst; however, the addition of hydrated barium hydroxide to the ceramic composite anode caused poor stability of the fuel cell performance.

페로브스카이트 태양전지용 홀 전도체 개발과 비납계 페로브스카이트 연구 동향

  • Song, Myeong-Gwan
    • Ceramist
    • /
    • v.21 no.1
    • /
    • pp.98-111
    • /
    • 2018
  • The lead-based perovskite (CH3NH3PbI3) material has a high molar coefficient, high crystallinity at low temperature, and long range of balanced electron-hole transport length. In addition, PCE of perovskite solar cells (PSCs) has been dramatically improved by over 22% by amending the electronic quality of perovskite and by using state-of-the-art hole transporting materials (HTMs) such as tetrakis(N,N-di-p-methoxyphenylamine)-9,9'-spirobifluorene (spiro-OMeTAD) due to enhanced charge transport toward the electrode via properly aligned energy levels with respect to the perovskite. Replacing the spiro-OMeTAD with new HTMs with the desired properties of appropriate energy levels, high hole mobility in its pristine form, low cost, and easy processable materials is necessary for attaining highly efficient and stable PSCs, which are anticipated to be truly compatible for practical application. Furthermore, Recently Pb-free perovskite materials much attention as an alternative light-harvesting active layer material instead of lead based perovskite in photovoltaic cells. In this work, we demonstrate a Pb-free perovskite material for the light harvesting and emitter as optoelectronic devices.

Case report of amniotic membrane derived-stem cells treatment for feline chronic obstructive pulmonary disease

  • Kim, Taeho;Noh, Seul Ah;Ju, Junguk
    • Journal of Animal Reproduction and Biotechnology
    • /
    • v.36 no.4
    • /
    • pp.323-326
    • /
    • 2021
  • A cat who is a 15-year-old and spayed female visited an animal clinic with severe coughing symptoms. Since the cat's coughing symptoms had worsened from the age of 10 and X-rays showed a bronchial pattern in the lungs, it was diagnosed as Chronic Obstructive Pulmonary Disease (COPD). She received three injections of stem cells isolated from the amniotic membrane on days 0, 7, and 23. Although there was no improvement in the clinical findings on the x-ray, the number of coughing was significantly reduced. In addition, even after long-term follow-up post treatment for a month, she was stable with almost no coughing.

The Fission Yeast Gene Encoding Monothiol Glutaredoxin 5 Is Regulated by Nitrosative and Osmotic Stresses

  • Kim, Hong-Gyum;Park, Eun-Hee;Lim, Chang-Jin
    • Molecules and Cells
    • /
    • v.20 no.1
    • /
    • pp.43-50
    • /
    • 2005
  • Glutaredoxin (Grx) is a small, heat-stable redox protein acting as a multi-functional glutathione (GSH)-dependent disulfide oxidoreductase. We have cloned the monothiol Grx5 gene from the genomic DNA of the fission yeast Schizosaccharomyces pombe. It has 1,904 bp, with one intron, and encodes a putative protein of 146 amino acids with a molecular mass of 16.5 kDa. Recombinant Grx5 produced functional Grx in S. pombe cells. NO-generating sodium nitroprusside (SNP, 1.0 and 2.0 mM) and potassium chloride (KCl, 0.2 and 0.5 M) increased the synthesis of ${\beta}$-galactosidase from a Grx5-lacZ fusion gene, and transcription of Grx5 was also enhanced by SNP and KCl. Synthesis of ${\beta}$-galactosidase from the Grx5-lacZ fusion was lower in Pap1-negative TP108-3C cells than in wild type KP1 cells, and when Pap1 was overproduced in KP1 cells, the level of ${\beta}$-galactosidase increased. We also found that Pap1 is involved in the induction of Grx5 by SNP and KCl. S. pombe Grx5 may play a crucial role in responses to nitrosative and osmotic stresses.

The Effect of Temperature on the Stability of Bioluminescence from Immobilized Photobacterium phosphoreum (저장 온도에 따른 고정화 Photobacterium phosphoreum의 Bioluminescence 안정성의 변화)

  • 김현숙;이은수;정성제;유승오;전억한
    • KSBB Journal
    • /
    • v.14 no.1
    • /
    • pp.91-95
    • /
    • 1999
  • The objective of this work was to improve bioluminescence stability of Photobacterium phosphoreum when it stored in view of developing continuous on-line monitoring system for pullutants. Long-term experiments were made to determine the effect of immobilization and storage temperature on the maintenance and stability of bioluminescence from luminescent bacteria. The immobilized cells of P. phosphoreum were compared with free cells in terms of maintenance of bioluminescence at room temperature. The bioluminescence of cells immobilized showed higher bioluminescence intensity that free and strontium bioluminescence stability was investigated with free and immobilized cells stored at $20^{\circ}C,\; 4^{\circ}C,\; -20^{\circ}C\;and\;-70^{\circ}C$for 20 days. Both free and immobilized cells stored at $4^{\circ}C$ emitted a stable bioluminescence while the bioluminescence markedly decreased with those stored at $20^{\circ}C,\;-20^{\circ}C\;and\; -70^{\circ}C$.

  • PDF

Zinc Increases Chemotactic Activity of Porcine Peripheral Blood Polymorphonuclear Cells

  • Seo, Dong-Hee;Kang, Byeong-Teck;Kang, Ji-Houn;Yang, Mhan-Pyo
    • Journal of Veterinary Clinics
    • /
    • v.35 no.5
    • /
    • pp.195-199
    • /
    • 2018
  • Zinc is necessary for normal functions in the immune system. The objective of the study is to examine the effect of zinc on the chemotactic activity of porcine peripheral blood polymorphonuclear cells (PMNs). A modified Boyden chamber was used to determine the directional migration distance of PMNs. Various concentrations of zinc showed no chemotactic activity to PMNs. However, culture supernatant from peripheral blood mononuclear cells (PBMCs) treated with zinc remarkably increased the chemotactic activity of PMNs when compared with culture supernatant from PBMCs treated without zinc. Culture supernatant from PBMCs treated without zinc also increased the migration distance of PMNs relative to vehicle control (medium alone). Increasing effect in chemotactic activity of PMNs by culture supernatant from PBMCs treated with zinc was inhibited by treatment of porcine anti-interleukin (IL)-8 polyclonal antibody (pAb). This effect was not affected by heat treatment ($4-85^{\circ}C$). This corresponded with heat stable physical characteristics of IL-8. These results suggest that zinc can upregulate the chemotaxis of PMNs, which is primary mediated by IL-8 chemotactic factor released from PBMCs treated with zinc.

Construction of a Transcriptome-Driven Network at the Early Stage of Infection with Influenza A H1N1 in Human Lung Alveolar Epithelial Cells

  • Chung, Myungguen;Cho, Soo Young;Lee, Young Seek
    • Biomolecules & Therapeutics
    • /
    • v.26 no.3
    • /
    • pp.290-297
    • /
    • 2018
  • We aimed to understand the molecular changes in host cells that accompany infection by the seasonal influenza A H1N1 virus because the initial response rapidly changes owing to the fact that the virus has a robust initial propagation phase. Human epithelial alveolar A549 cells were infected and total RNA was extracted at 30 min, 1 h, 2 h, 4 h, 8 h, 24 h, and 48 h post infection (h.p.i.). The differentially expressed host genes were clustered into two distinct sets of genes as the infection progressed over time. The patterns of expression were significantly different at the early stages of infection. One of the responses showed roles similar to those associated with the enrichment gene sets to known 'gp120 pathway in HIV.' This gene set contains genes known to play roles in preventing the progress of apoptosis, which infected cells undergo as a response to viral infection. The other gene set showed enrichment of 'Drug Metabolism Enzymes (DMEs).' The identification of two distinct gene sets indicates that the virus regulates the cell's mechanisms to create a favorable environment for its stable replication and protection of gene metabolites within 8 h.

Light Induced Degradation in Crystalline Si Solar Cells (결정질 실리콘 태양전지의 광열화 현상)

  • Tark, Sung-Ju;Kim, Young-Do;Kim, Soo-Min;Park, Sung-Eun;Kim, Dong-Hwan
    • New & Renewable Energy
    • /
    • v.8 no.1
    • /
    • pp.24-34
    • /
    • 2012
  • The main issue of boron doped p-type czochralski-grown silicon solar cells is the degradation when they are exposed to light or minority carriers injection. This is due to the meta-stable defect such as boron-oxygen in the Cz-Si material. Although a clear explanation is still researching, recent investigations have revealed that the Cz-Si defect is related with the boron and the oxygen concentration. They also revealed how these defects act a recombination centers in solar cells using density function theory (DFT) calculation. This paper reviews the physical understanding and gives an overview of the degradation models. Therefore, various methods for avoiding the light-induced degradation in Cz-Si solar cells are compared in this paper.

Photosynthetic Characteristics of Intact Cells and Thylakoid Membranes of Synechococcus PCC7002 with Polyvinyalcohol-Immobilization (Synechococcus PCC7002의 세포 및 틸라코이드 막의 Polyvinylalcohol 고정화에 의한 광합성 특성)

  • 윤지은;전현식
    • KSBB Journal
    • /
    • v.8 no.2
    • /
    • pp.185-191
    • /
    • 1993
  • Highly stable $O_2$-evolving cells and thylakoid membranes have been obtained from the cyanobacterium, Synechococcus PCC7002, by immobilization with polyvinylalcohol(PVA). The absorption peak showed the blue-shift of about 3 nm after immobilization of intact cells and thylakoid membranes as well as isolation of thylakoid membranes. Photosynthetic electron transport activities, especially PS II activity showed greater stability in the PVA-immobilized cells and thylakoid membranes when stored at $4^{\circ}C$ than in those at $25^{\circ}C$. When the cells were threated at higher temperature, the level of Fo and Fv increased. After imobilization, however, Fo showed no change. This suggests that the immobilization can protect against the damages of PS II complex, especially a water-spiliting system, by heat treatment.

  • PDF