• Title/Summary/Keyword: molecular processes

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Mitochondria-mediated defense mechanisms against pathogens in Caenorhabditis elegans

  • Kwon, Sujeong;Kim, Eun Ji E.;Lee, Seung-Jae V.
    • BMB Reports
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    • v.51 no.6
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    • pp.274-279
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    • 2018
  • Mitochondria are crucial organelles that generate cellular energy and metabolites. Recent studies indicate that mitochondria also regulate immunity. In this review, we discuss key roles of mitochondria in immunity against pathogen infection and underlying mechanisms, focusing on discoveries using Caenorhabditis elegans. Various mitochondrial processes, including mitochondrial surveillance mechanisms, mitochondrial unfolded protein response ($UPR^{mt}$), mitophagy, and reactive oxygen species (ROS) production, contribute to immune responses and resistance of C. elegans against pathogens. Biological processes of C. elegans are usually conserved across phyla. Thus, understanding the mechanisms of mitochondria-mediated defense responses in C. elegans may provide insights into similar mechanisms in complex organisms, including mammals.

Emerging functions for ANKHD1 in cancer-related signaling pathways and cellular processes

  • de Almeida, Bruna Oliveira;Machado-Neto, Joao Agostinho
    • BMB Reports
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    • v.53 no.8
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    • pp.413-418
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    • 2020
  • ANKHD1 (ankyrin repeat and KH domain containing 1) is a large protein characterized by the presence of multiple ankyrin repeats and a K-homology domain. Ankyrin repeat domains consist of widely existing protein motifs in nature, they mediate protein-protein interactions and regulate fundamental biological processes, while the KH domain binds to RNA or ssDNA and is associated with transcriptional and translational regulation. In recent years, studies containing relevant information on ANKHD1 in cancer biology and its clinical relevance, as well as the increasing complexity of signaling networks in which this protein acts, have been reported. Among the signaling pathways of interest in oncology regulated by ANKHD1 are Hippo signaling, JAK/STAT, and STMN1. The scope of the present review is to survey the current knowledge and highlight future perspectives for ANKHD1 in the malignant phenotype of cancer cells, exploring biological, functional, and clinical reports of this protein in cancer.

Nonsense-mediated mRNA decay at the crossroads of many cellular pathways

  • Lejeune, Fabrice
    • BMB Reports
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    • v.50 no.4
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    • pp.175-185
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    • 2017
  • Nonsense-mediated mRNA decay (NMD) is a surveillance mechanism ensuring the fast decay of mRNAs harboring a premature termination codon (PTC). As a quality control mechanism, NMD distinguishes PTCs from normal termination codons in order to degrade PTC-carrying mRNAs only. For this, NMD is connected to various other cell processes which regulate or activate it under specific cell conditions or in response to mutations, mis-regulations, stresses, or particular cell programs. These cell processes and their connections with NMD are the focus of this review, which aims both to illustrate the complexity of the NMD mechanism and its regulation and to highlight the cellular consequences of NMD inhibition.

Effect of Botulinum Toxin A on Proliferation and Apoptosis in the T47D Breast Cancer Cell Line

  • Bandala, Cindy;Perez-Santos, Jose Luis Martin;Lara-Padilla, Eleazar;Delgado Lopez, Ma. Guadalupe;Anaya-Ruiz, Maricruz
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.2
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    • pp.891-894
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    • 2013
  • The present study was performed to assess the activity of the botulinum toxin A on breast cancer cells. The T47D cell line was exposed to diverse concentrations of the botulinum toxin A and cell viability and apoptosis were estimated using MTT and propidium iodine/annexin V methods, respectively. Botulinum toxin A exerted greater cytotoxic activity in T47D cells in comparison with MCF10A normal cells; this appeared to be via apoptotic processes caspase-3 and -7. In conclusion, botulinum toxin A induces caspase-3 and -7 dependent apoptotic processes in the T47D breast cancer cell line.

A Study on the Improvement of Science Education With Experimental Model and it's Programming(I) (과학교육 개선을 위한 실험모델 제작에 관한 연구(I))

  • Lee, Ki-Jong;Lee, Kwang-Ho;Lee, Jong-Chul;Kim, Ja-Hong
    • Journal of The Korean Association For Science Education
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    • v.9 no.2
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    • pp.13-27
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    • 1989
  • A curriculum for teaching materials in Science Education was studied as a model for modified experiment on fundamental courses. Conscious effort can be made to desingn experiments that require minimum apparatus: that require low-cost equipment that can be made from cheap locally available materials. Computer-aided instruction programs at high school, freshman course level have been developed. The software package was consist of five programs: The program contains explanation and problems for the calculation of resonance energy, molecular structure, mole concept. Rutherford's experiment. thermodynamic processes. Special course equipment package explanation mole concept, Rutherford's experiment, thermodynamic processes. Special course were designed in Science Education with the understanding that to a certain extent science values would be covered in all of the modified experiments and program models.

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Particle Simulation on the Effect of Grid Cathode Geometry in SCBF Device (SCBF 장치에서 그리드 음극 구조의 영향에 대한 입자 시뮬레이션)

  • Ju, Heung-Jin;Park, Jeong-Ho;Ko, Kwang-Cheol
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.20 no.8
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    • pp.742-747
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    • 2007
  • In 2-dimensional SCBF (Spherically Convergent Beam Fusion) device, the effect on neutron production rate of the grid cathode geometry was simulated. The motion of Particles was tracked using Monte Carlo Method including the atomic and molecular collision processes and potential distribution was calculated by Finite Element Method, Main processes of the discharge were the ionization of $D_2$ by fast $D_2^+\;ion$. As the number of cathode rings was small and the size of grid cathode decreased, the ion current increased and neutron production rate will also increase. The star mode discharge which is a very important characteristic in SCBF device, was confirmed by the ionization position.

Upstream Regulators and Downstream Effectors of NADPH Oxidases as Novel Therapeutic Targets for Diabetic Kidney Disease

  • Gorin, Yves;Wauquier, Fabien
    • Molecules and Cells
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    • v.38 no.4
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    • pp.285-296
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    • 2015
  • Oxidative stress has been linked to the pathogenesis of diabetic nephropathy, the complication of diabetes in the kidney. NADPH oxidases of the Nox family, and in particular the homologue Nox4, are a major source of reactive oxygen species in the diabetic kidney and are critical mediators of redox signaling in glomerular and tubulointerstitial cells exposed to the diabetic milieu. Here, we present an overview of the current knowledge related to the understanding of the role of Nox enzymes in the processes that control mesangial cell, podocyte and tubulointerstitial cell injury induced by hyperglycemia and other predominant factors enhanced in the diabetic milieu, including the renin-angiotensin system and transforming growth factor-${\beta}$. The nature of the upstream modulators of Nox enzymes as well as the downstream targets of the Nox NADPH oxidases implicated in the propagation of the redox processes that alter renal biology in diabetes will be highlighted.

Energy Transfer between Calixarene and Naphthalene

  • Kook, Seong-Keun
    • Bulletin of the Korean Chemical Society
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    • v.23 no.8
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    • pp.1111-1115
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    • 2002
  • The photoluminescence of calixarene crystals has been studied as functions of temperature, time, and concentration. The vibronic bands shift to longer wavelength and become significantly sharper as temperature decreases. The experimental results r eveal that the structural transformation occur during the annealing process. Time-resolved spectra of calixarene at 12 K are monitored. Spectral features, which demonstrate characteristic of energy transfer processes, are not observed. The depopulation of excited state density is mainly controlled by unimolecular decay process dominating other decay processes. The lifetime was found to be 2.6 $\pm$ 0.1 ns. For the case of calixarene mixed with naphthalene, the fluorescence spectrum shows that the band centered at 340 nm lies 2840 $cm^{-1}$ below the relatively broad 310 nm band found for calixarene crystals. The spectra also exhibit that the emission intensity increases with increasing calixarene concentration. The results are evident that the calixarene emission is quenched by the naphthalene. Phosphorescence of calixarene mixed with naphthalene crystals is observed to determine whether the emission is due to naphthalene. The phosphorescence peaks were compared with the ground-state vibrational frequencies of naphthalene and found to be in good agreement. The results indicate that inter-molecular energy transfer occurs between calixarene and naphthalene.

The role of cell type-specific mitochondrial dysfunction in the pathogenesis of Alzheimer's disease

  • Kim, Dong Kyu;MookJung, Inhee
    • BMB Reports
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    • v.52 no.12
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    • pp.679-688
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    • 2019
  • The decrease of metabolism in the brain has been observed as the important lesions of Alzheimer's disease (AD) from the early stages of diagnosis. The cumulative evidence has reported that the failure of mitochondria, an organelle involved in diverse biological processes as well as energy production, maybe the cause or effect of the pathogenesis of AD. Both amyloid and tau pathologies have an impact upon mitochondria through physical interaction or indirect signaling pathways, resulting in the disruption of mitochondrial function and dynamics which can trigger AD. In addition, mitochondria are involved in different biological processes depending on the specific functions of each cell type in the brain. Thus, it is necessary to understand mitochondrial dysfunction as part of the pathological phenotypes of AD according to each cell type. In this review, we summarize that 1) the effects of AD pathology inducing mitochondrial dysfunction and 2) the contribution of mitochondrial dysfunction in each cell type to AD pathogenesis.

Dual-Curable Acrylic Pressure-Sensitive Adhesives Based on UV and Thermal Processes

  • Kim, Yang-Bae;Park, Su-Cheol;Kim, Hyun-Kyoung;Hong, Jin-Who
    • Macromolecular Research
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    • v.16 no.2
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    • pp.128-133
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    • 2008
  • Several dual-curable acrylic pressure-sensitive adhesives (PSA) were synthesized by the radical polymerization of acrylic monomers containing benzophenone, hydroxyl, and alkyl groups. The optimum extent of UV-induced cure was determined by varying the content of the benzophenone groups (the photoinitiator) from 0.5 to 1.5 wt%. The weight average molecular weight of the polymers obtained ranged from 300,000 to 700,000 amu. The coated pressure-sensitive adhesives were cured either by short UV exposure to induce the grafting of acrylic polymers, or by heating for 6 hat $60^{\circ}C$ to promote the reactions between the polyisocyanates and hydroxyl groups. The dual-curing behavior was determined by monitoring both processes quantitatively by infrared spectroscopy. The developed dual-curable acrylic pressure-sensitive adhesives were found to compensate for the limitations in UV-induced curing of thick coatings.