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Search Results: 1 - 10 of 5265 matches for " Sangwoon Chung "
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NF-κB Inducing Kinase, NIK Mediates Cigarette Smoke/TNFα-Induced Histone Acetylation and Inflammation through Differential Activation of IKKs
Sangwoon Chung, Isaac K. Sundar, Jae-Woong Hwang, Fiona E. Yull, Timothy S. Blackwell, Vuokko L. Kinnula, Michael Bulger, Hongwei Yao, Irfan Rahman
PLOS ONE , 2011, DOI: 10.1371/journal.pone.0023488
Abstract: Background Nuclear factor (NF)-κB inducing kinase (NIK) is a central player in the non-canonical NF κB pathway, which phosphorylates IκB kinase α (IKKα) resulting in enhancement of target gene expression. We have recently shown that IKKα responds to a variety of stimuli including oxidants and cigarette smoke (CS) regulating the histone modification in addition to its role in NF-κB activation. However, the primary signaling mechanism linking CS-mediated oxidative stress and TNFα with histone acetylation and pro-inflammatory gene transcription is not well understood. We hypothesized that CS and TNFα increase NIK levels causing phosphorylation of IKKα, which leads to histone acetylation. Methodology To test this hypothesis, we investigated whether NIK mediates effects of CS and TNFα on histone acetylation in human lung epithelial cells in vitro and in lungs of mouse exposed to CS in vivo. CS increased the phosphorylation levels of IKKα/NIK in lung epithelial cells and mouse lungs. NIK is accumulated in the nuclear compartment, and is recruited to the promoters of pro-inflammatory genes, to induce posttranslational acetylation of histones in response to CS and TNFα. Cells in which NIK is knocked down using siRNA showed partial attenuation of CSE- and TNFα-induced acetylation of histone H3 on pro-inflammatory gene promoters. Additional study to determine the role of IKKβ/NF-κB pathway in CS-induced histone acetylation suggests that the canonical pathway does not play a role in histone acetylation particularly in response to CS in mouse lungs. Conclusions Overall, our findings provide a novel role for NIK in CS- and TNFα-induced histone acetylation, especially on histone H3K9.
Mitogen- and Stress-Activated Kinase 1 (MSK1) Regulates Cigarette Smoke-Induced Histone Modifications on NF-κB-dependent Genes
Isaac K. Sundar, Sangwoon Chung, Jae-woong Hwang, John D. Lapek, Michael Bulger, Alan E. Friedman, Hongwei Yao, James R. Davie, Irfan Rahman
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0031378
Abstract: Cigarette smoke (CS) causes sustained lung inflammation, which is an important event in the pathogenesis of chronic obstructive pulmonary disease (COPD). We have previously reported that IKKα (I kappaB kinase alpha) plays a key role in CS-induced pro-inflammatory gene transcription by chromatin modifications; however, the underlying role of downstream signaling kinase is not known. Mitogen- and stress-activated kinase 1 (MSK1) serves as a specific downstream NF-κB RelA/p65 kinase, mediating transcriptional activation of NF-κB-dependent pro-inflammatory genes. The role of MSK1 in nuclear signaling and chromatin modifications is not known, particularly in response to environmental stimuli. We hypothesized that MSK1 regulates chromatin modifications of pro-inflammatory gene promoters in response to CS. Here, we report that CS extract activates MSK1 in human lung epithelial (H292 and BEAS-2B) cell lines, human primary small airway epithelial cells (SAEC), and in mouse lung, resulting in phosphorylation of nuclear MSK1 (Thr581), phospho-acetylation of RelA/p65 at Ser276 and Lys310 respectively. This event was associated with phospho-acetylation of histone H3 (Ser10/Lys9) and acetylation of histone H4 (Lys12). MSK1 N- and C-terminal kinase-dead mutants, MSK1 siRNA-mediated knock-down in transiently transfected H292 cells, and MSK1 stable knock-down mouse embryonic fibroblasts significantly reduced CS extract-induced MSK1, NF-κB RelA/p65 activation, and posttranslational modifications of histones. CS extract/CS promotes the direct interaction of MSK1 with RelA/p65 and p300 in epithelial cells and in mouse lung. Furthermore, CS-mediated recruitment of MSK1 and its substrates to the promoters of NF-κB-dependent pro-inflammatory genes leads to transcriptional activation, as determined by chromatin immunoprecipitation. Thus, MSK1 is an important downstream kinase involved in CS-induced NF-κB activation and chromatin modifications, which have implications in pathogenesis of COPD.
Krüppel Like Factor 4 Promoter Undergoes Active Demethylation during Monocyte/Macrophage Differentiation
Manjula Karpurapu, Ravi Ranjan, Jing Deng, Sangwoon Chung, Yong Gyu Lee, Lei Xiao, Teja Srinivas Nirujogi, Jeffrey R. Jacobson, Gye Young Park, John W Christman
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0093362
Abstract: The role of different lineage specific transcription factors in directing hematopoietic cell fate towards myeloid lineage is well established but the status of epigenetic modifications has not been defined during this important developmental process. We used non proliferating, PU.1 inducible myeloid progenitor cells and differentiating bone marrow derived macrophages to study the PU.1 dependent KLF4 transcriptional regulation and its promoter demethylation during monocyte/macrophage differentiation. Expression of KLF4 was regulated by active demethylation of its promoter and PU.1 specifically bound to KLF4 promoter oligo harboring the PU.1 consensus sequence. Methylation specific quantitative PCR and Bisulfite sequencing indicated demethylation of CpG residues most proximal to the transcription start site of KLF4 promoter. Cloned KLF4 promoter in pGL3 Luciferase and CpG free pcpgf-bas vectors showed accentuated reporter activity when co-transfected with the PU.1 expression vector. In vitro methylation of both KLF4 promoter oligo and cloned KLF4 promoter vectors showed attenuated in vitro DNA binding activity and Luciferase/mouse Alkaline phosphotase reporter activity indicating the negative influence of KLF4 promoter methylation on PU.1 binding. The Cytosine deaminase, Activation Induced Cytidine Deaminase (AICDA) was found to be critical for KLF4 promoter demethylation. More importantly, knock down of AICDA resulted in blockade of KLF4 promoter demethylation, decreased F4/80 expression and other phenotypic characters of macrophage differentiation. Our data proves that AICDA mediated active demethylation of the KLF4 promoter is necessary for transcriptional regulation of KLF4 by PU.1 during monocyte/macrophage differentiation.
Phylogenetic analysis and characterization of mitochondrial DNA for Korean native cattle  [PDF]
Hoyoung Chung
Open Journal of Genetics (OJGen) , 2013, DOI: 10.4236/ojgen.2013.31003
This study was aimed to preserve mitochondria from liver tissues of Korean native cattle (KNC) as genetic resources and to analyze phylogenetic relationships among cattle breeds using the whole sequences of mtDNA. Mitochondria of KNC has been isolated with the alkaline lysis procedure using1 gof liver tissues, and measurements showed numbers of cells (2.64 × 1010), concentration (114.6 ug/ml), proteins (0.278 ug/ml), and absorbance (0.029) in 260 nm. Mitochondrial DNAs (mtDNA) were extracted from the isolated mitochondria to determine whole sequences that can be used to estimate genetic distances among cattle breeds. Designing of primers based on the bovine mtDNA sequence was resulted in 16 primer sets covering the whole mtDNA regions. The analysis of 40 KNC mtDNA sequences revealed 69 polymorphic sites that were less than the average number of SNP (single nucleotide polymorphism) for other populations (82 sites) in this study. As expected, the highest observation of SNPs was found in the D-loop region, and a total of 29 SNPs were shared between cattle populations. The haplotype analysis, which used 13 SNPs located in D-loop, COX2, ND5, CYTB, and non coding regions, revealed that KNC showed clearly different haplotypes that may be used to distinguish KNC from other breeds as well as to characterize individual identifications. The phylogenetic analysis revealed that KNC showed a relatively close genetic distance with Japanese black cattle (JBC) comparing with other breeds. Estimations of the average nucleotide diversity (0.0008) and the ratio of transition/ transversion (0.1050) of KNC were placed somewhere in the middle of genetic diversity among cattle breeds. The identified genetic variants and results of phylogenetic analysis will help understanding the phylogenetic relationships of KNC and provide useful genetic information for further studies regarding SNPs in mtDNA regions.
Solid Boundary as Energy Source and Sink in a Dry Granular Dense Flow: A Comparison between Two Turbulent Closure Models  [PDF]
Chung Fang
Engineering (ENG) , 2014, DOI: 10.4236/eng.2014.613087
Abstract: Solid boundary as energy source and sink of the turbulent kinetic energy of the grains, and its influence on the mean and turbulent features of a dry granular dense flow, are investigated by using the proposed zero- and first-order turbulent closure models. The first and second laws of thermodynamics are used to derive the equilibrium closure relations, with the dynamic responses postulated by a quasi-static theory for weak turbulent intensity. Two closure models are applied to analyses of a gravity-driven flow down an inclined moving plane. While the calculated mean porosity and velocity correspond to the experimental outcomes, the influence of the turbulent eddy evolution can be taken into account in the first-order model. Increasing velocity slip on the inclined plane tends to enhance the turbulent dissipation nearby, and the turbulent kinetic energy near the free surface. The turbulent dissipation demonstrates a similarity with that of Newtonian fluids in turbulent boundary layer flows. While two-fold roles of the solid boundary are apparent in the first-order model, its role as an energy sink is more obvious in the zero-order model.
Human Cultural Evolution: Postmodernity as Rational Global Diversity  [PDF]
Dingyu Chung
Open Journal of Social Sciences (JSS) , 2017, DOI: 10.4236/jss.2017.55022
Abstract: This paper proposes that human culture has evolved from authoritative local premodernity through rational local modernity to the coming rational global postmodernity with diverse cultural types. Premodernity, modernity, and postmodernity are the cultural adaptations to the drastic social changes from the Agricultural, Industrial, and Information Revolutions. The cultural types analogous to biological species are the nine cultural types derived from the instinctive cultural type model based on the instinctive sociality trichotomy (individualistic, collectivistic, and interdependent) and the instinctive worldview trichotomy (territorial, connective, and competitive). Western culture originated from the Middle East and Greece has competitive worldview, while Eastern culture originated from India and China has connective worldview. Different cultural types have different perceptions, moralities, religions, politics, and economies. Currently, the world is the chaotic diverse global society where the cultural types clash. The coming postmodernity as rational global diversity is produced by the three rational global diverse systems. The rational global diverse system for the coming postmodern international politics is the three-tier international politics consisting of nations with geopolitical boundaries, the 12 regional communities with cultural-geographic boundaries, and the global international organizations without boundary. The rational global diverse system for the coming postmodern international trade is the trichotomic international trade containing free competitive, free connective, and fair protectionist international trades. The rational global diverse system for the coming postmodern common ground between religion and science is the cultural theology of trinity consisting of the transcendental, immanent, and imaginary cultural origins. The coming postmodernity as rational global diversity will bring rational order and peace among global diverse cultural types.
The Big Five Social System Traits as the Source of Personality Traits, MBTI, Social Styles, Personality Disorders, and Cultures  [PDF]
Dingyu Chung
Open Journal of Social Sciences (JSS) , 2017, DOI: 10.4236/jss.2017.59019
This paper proposes the big five social system traits as the fixed, clear, and workable social solutions to the social issues under the different social conditions. Under the big five social system traits, different fixed and clear personal behaviors are developed by different people under different social conditions, so the big five social system traits are the source of different aspects of human behavior in terms of personality traits in the big five personality traits, personality types in the MBTI, social styles in the social style model, personality disorders in the DSM-5, social group deviances derived from the DSM-5, and religious, political, and economic systems in Western and Eastern cultures as described in this paper. The big five social system traits consist of sociality (individualistic-collectivistic-interdependent) traits to the issue of social formation, worldview traits (connective-competitive-territorial or people-tasks) to the issue of social boundary, awareness traits (concrete-imaginary) to the issue of social stress, activity traits (constructional-mobilized) to the issue of social duration, and legitimacy traits (authoritative-rational) to the issue of social uniformity. As a result, the big five social system traits provide the base for the unified theory of human behavior to unify different aspects of human behavior and to produce the common ground for diverse views to communicate.
The Mental Protection System for Protective Behaviors: The Social Brain and the Mental Immune System  [PDF]
Dingyu Chung
Journal of Behavioral and Brain Science (JBBS) , 2018, DOI: 10.4236/jbbs.2018.81003
Abstract: The physical protection system of the body consists of the protective organs for vulnerable body parts-functions and the protective countermeasures against invaders (pathogens), but to survive, the body also requires the protective social groups for vulnerable social members-functions and the protective instinctive mental countermeasures against adversities such as hardship, danger, and unfamiliarity-uncertainty. As a result, this paper proposes that the mental protection system of the body consists of the social brain to set up the protective social groups for vulnerable social members-functions and the mental immune system to produce the protective mental countermeasures against adversities. This paper proposes that from the social brain, the protective social groups include alliance group for vulnerable individuals, kinship-friendship group for vulnerable children, interdependent specialists group for vulnerable pregnant females, territorial group for social boundary, connective group for social connection, and competitive group for social competition. From the mental immune system, the mental protective countermeasures include comforter against hardship, hyperactivity against danger, phobia against unfamiliarity-uncertainty, and rationality against unfamiliarity-uncertainty. The overactive mental immune system causes mental allergies and auto immune diseases as personality-mental disorders against ubiquitous harmful and harmless perceived adversities, correlating to physical allergies and auto immune diseases against ubiquitous harmful and harmless detected invaders. The mental protection system also produces personality traits, social moralities, social organizations, social systems, religions, and cultures as described in this paper. The mental protective system is the source of protective behaviors.
The Eight Stages of Psychosocial Protective Development: Developmental Psychology  [PDF]
Dingyu Chung
Journal of Behavioral and Brain Science (JBBS) , 2018, DOI: 10.4236/jbbs.2018.86024
Abstract: The proposed universal psychological mechanism for developmental psychology is the mental protective system whose different parts emerge and mature in the eight different stages of psychosocial protective development under different social interactions. The proposed eight stages of psychosocial protective development are childhood (infancy, toddlerhood, pre-juvenile age, and juvenile age), adolescence, early young adulthood, late young adulthood, early middle adulthood, late middle adulthood, early late adulthood, and late late adulthood. The mental protection system consists of four socialities (collectivistic, individualistic, interdependent, and generativity), three worldviews (territorial, competitive, and cooperative), and the mental immune system for four regulated and unregulated countermeasures (hyperactivity, phobia, comforter, and rationality) against adversities. During childhood, dependent children have collectivistic sociality under the protection of committed parents and territorial worldview with the boundary of family. Children start with the unregulated mental immune system without delayed gratification due to mental immaturity, and gradually acquire the regulated mental immune system with delayed gratification through mental maturity. Adolescents transit to adulthood. Independent adults have the regulated metal immune system, individualistic sociality with reciprocity, and competitive-cooperative worldviews without boundary. After the age of 50, older people as elder leaders-mentors develop generativity sociality to protect next generation. The paper shows that the mental protective system as the universal psychological mechanism for developmental psychology explains clearly psychosocial protective development, the human evolution, the Piaget’s cognitive development, the Erikson’s psychosocial (ego-social) development, the Confucius’ (educated person’s) six milestones of life, and parent-child relation in the Abrahamic religions (Judaism, Christianity, and Islam) and Confucianism.
Optimal Commodity Advertising in Bilateral Oligopoly  [PDF]
Chanjin Chung
Theoretical Economics Letters (TEL) , 2018, DOI: 10.4236/tel.2018.811128
Abstract: This study derives an optimal commodity advertising intensity rule for a vertically related market under bilateral oligopoly. The new optimality condition derived in this study extends the seminal Dorfman-Steiner Theorem [1] and recently published optimal advertising conditions by two major aspects. First, we strengthen the previous work by considering potential market power exertion in all buying (input) and selling (output) markets, i.e., all four adjacent upstream and downstream markets of processors and retailers. Second, we use a primal production function approach to avoid the symmetry assumption that many earlier studies imposed on conjectural elasticities of input and/or output markets. Our new condition suggests that, without considering the potential market power exertions, the optimal advertising intensity and expenditures are overestimated. Our derivation also indicates that previous optimal advertising conditions derived under the assumption of fixed proportion technology could underestimate the optimal intensity and expenditures, particularly when advertising elasticity is elastic.
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