• 제목/요약/키워드: types of evidence

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Emerging Role of NRF2 Signaling in Cancer Stem Cell Phenotype

  • Steffanus P. Hallis;Jin Myung Kim;Mi-Kyoung Kwak
    • Molecules and Cells
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    • 제46권3호
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    • pp.153-164
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    • 2023
  • Cancer stem cells (CSCs) are a small population of tumor cells characterized by self-renewal and differentiation capacity. CSCs are currently postulated as the driving force that induces intra-tumor heterogeneity leading to tumor initiation, metastasis, and eventually tumor relapse. Notably, CSCs are inherently resistant to environmental stress, chemotherapy, and radiotherapy due to high levels of antioxidant systems and drug efflux transporters. In this context, a therapeutic strategy targeting the CSC-specific pathway holds a promising cure for cancer. NRF2 (nuclear factor erythroid 2-like 2; NFE2L2) is a master transcription factor that regulates an array of genes involved in the detoxification of reactive oxygen species/electrophiles. Accumulating evidence suggests that persistent NRF2 activation, observed in multiple types of cancer, supports tumor growth, aggressive malignancy, and therapy resistance. Herein, we describe the core properties of CSCs, focusing on treatment resistance, and review the evidence that demonstrates the roles of NRF2 signaling in conferring unique properties of CSCs and the associated signaling pathways.

Environments of Galaxies and Their Effects on Galaxy Properties

  • Yoon, Yongmin;Im, Myungshin
    • 천문학회보
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    • 제44권2호
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    • pp.38.2-38.2
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    • 2019
  • In the history of universe, galaxies are consistently affected by surrounding medium and neighbor galaxies. These effects control galaxy evolution, making properties of galaxies diverse and dependent on environments. We investigate environments of various types of galaxies and how they affect galaxy properties, such as bar structures and galaxy sizes, etc. First, we present the observational evidence that bars can form from a cluster-cluster interaction. The evidence indicates that bars can form due to a large-scale violent phenomenon, and cluster-cluster interaction should be considered as an important channel for bar formation. Second, we discover for the first time that local early-type galaxies heavier than 1011.2 Msol show a clear environmental dependence in mass-size relation, in such a way that galaxies are as much as 20 - 40% larger in densest environments than in underdense environments. This result suggests that mergers played a significant role in the growth of massive galaxies in dense environments as expected in theory. Lastly, we investigate environments of the most massive galaxies and extremely massive quasars. By doing so, we find that massive galaxies are a much better signpost for galaxy clusters than massive quasars.

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DNA-Dependent Protein Kinase Catalytic Subunit (DNA-PKcs): Beyond the DNA Double-Strand Break Repair

  • Ye-Rim Lee;Gi-Sue Kang;Taerim Oh;Hye-Ju Jo;Hye-Joon Park;G-One Ahn
    • Molecules and Cells
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    • 제46권4호
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    • pp.200-205
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    • 2023
  • DNA-dependent protein kinase catalytic subunit (DNA-PKcs), a member of the phosphatidylinositol 3-kinase-related kinase family is a well-known player in repairing DNA double-strand break through non-homologous end joining pathway. This mechanism has allowed us to understand its critical role in T and B cell development through V(D)J recombination and class switch recombination, respectively. We have also learned that the defects in these mechanisms lead to the severely combined immunodeficiency (SCID). Here we highlight some of the latest evidence where DNA-PKcs has been shown to localize not only in the nucleus but also in the cytoplasm, phosphorylating various proteins involved in cellular metabolism and cytokine production. While it is an exciting time to unveil novel functions of DNA-PKcs, one should carefully choose experimental models to study DNA-PKcs as the experimental evidence has been shown to differ between cells of defective DNA-PKcs and those of DNA-PKcs knockout. Moreover, while there are several DNA-PK inhibitors currently being evaluated in the clinical trials in an attempt to increase the efficacy of radiotherapy or chemotherapy, multiple functions and subcellular localization of DNA-PKcs in various types of cells may further complicate the effects at the cellular and organismal level.

전국 의료기관의 냉 요법 실무지침 및 임상간호사의 냉 요법 실무 현황 (Nursing Protocols of Cold Application in Different Medical Institutions in Korea)

  • 신용순
    • 임상간호연구
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    • 제21권3호
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    • pp.355-365
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    • 2015
  • Purpose: The purpose of this study was to evaluate nursing protocols for superficial cryotherapy in different medical institutions. Methods: The study was conducted with a cross-sectional descriptive design. The medical institutions including general hospitals, hospitals, and geriatric hospitals were randomly selected. A total of 435 nurses from 126 institutions completed a questionnaire. Data were collected from December 2014 to June 2015. Results: Forty-two institutions (39.5%) had nursing protocol for cryotherapy. The nurses reported that durations of cold application were 2 minutes to 5 hours. Frequently used cold therapy devices in order of frequency were frozen gel packs, ice packs, and frozen IV fluid bags. There were variances in the duration of cold application according to the types of institution ($x^2=7.78$, p=.020) and nursing units ($x^2=26.42$, p<.001). In addition, intervals of cold application were different according to the nursing units (x=12.23, p=.032). There were differences in cold application instruments by regional groups (x=70.38, p<.001). Most of the nurses (95.6%) responded that national nursing protocol for superficial cryotherapy were needed. Conclusion: There were difficulties in providing consistent nursing interventions because of the practical differences and absence of evidence-based guidelines for cryotherapy. The researchers recommend that basic studies with various instruments be conducted and proper nursing protocols be developed for cryotherapy.

Political Connections and CSR Disclosures in Indonesia

  • SARASWATI, Erwin;SAGITAPUTRI, Ananda;RAHADIAN, Yan
    • The Journal of Asian Finance, Economics and Business
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    • 제7권11호
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    • pp.1097-1104
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    • 2020
  • This research seeks to provide evidence about how political connections, proxied by government ownership and the existence of politically connected board members, affect the extent of corporate social responsibility (CSR) disclosures in Indonesian listed companies. This research uses the legitimacy theory as a basis for explaining management's motivation for disclosing its CSR. The sample consists of 131 firm-year observations from 38 non-financial public companies that published sustainability reports from 2013 to 2017. We measured the CSR disclosures using a disclosure checklist on the sustainability reports. We subsequently processed the data using a random effect (RE) linear regression. The result shows that CSR disclosures were greater in government-owned companies but lower in companies that have politically connected board members. The results support the legitimacy theory that the government intends to demonstrate legitimate national economic and political conditions by showing that government-owned companies are sustainable. However, CSR disclosures seem to have a substitutive relationship with the existence of politically connected board members, since those political connections may protect the company from public pressure and/or the risk of litigation, reducing the need for CSR disclosures. This research provides evidence that different types of political connections may have different impacts on corporate disclosures.

Against the Asymmetric CP- V2 Analysis of Old English

  • Yoon, Hee-Cheol
    • 한국영어학회지:영어학
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    • 제4권2호
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    • pp.117-149
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    • 2004
  • The paper is to argue against the asymmetric CP-V2 analysis of Old English, according to which finite verbs invariably undergo movement into a clause-final T within subordinate clauses and reach the functional head C within main clauses. The asymmetric CP-V2 analysis, first of all, faces difficulty in explaining a wide range of post-verbal elements within subordinate clauses. To resolve the problem, the analysis has to abandon the obligatoriness of V-to-T movement or introduce various types of extraposition whose status is dubious as a legitimate syntactic operation. Obligatory V-to-T movement in Old English lacks conceptual justification as well. Crosslinguistic evidence reveals that morphological richness in verbal inflection cannot entail overt verb movement. Moreover, the operation is always string-vacuous under the asymmetric CP- V2 analysis and has no effect at the interfaces, in violation of the principle of economy. The distribution of Old English finite verbs in main clauses also undermines the asymmetric CP-V2 analysis. Conceptually speaking, a proper syntactic trigger cannot be confirmed to motivate obligatory verb movement to C. The operation not only gets little support from nominative Case marking, the distribution of expletives, or complementizer agreement but also requires the unconvincing stipulation that expletives as well as sentence-initial subjects result from string-vacuous topicalization. Finally, textual evidence testifies that Old English sometimes permits non-V2 ordering patterns, many of which remain unexplained under the asymmetric CP-V2 analysis.

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Foreign Capital Flows, Banking Stability and the Role of International Trade Cooperation and Distribution an Empirical Analysis from the ASEAN Region

  • LU, Chi Huu;LUONG, Thuy Thi Thu
    • 유통과학연구
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    • 제20권7호
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    • pp.23-33
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    • 2022
  • Purpose: Although foreign capital flows have played a vital role in fostering the economic growth in recipient countries, there are some concerns about the adverse impact of international capital flows on the banking stability. Hence, the study revisits this issue to explore the relationship between the different types of foreign investments and banking stability in ASEAN region. Research design, data and methodology: Based on the bank-level data of 96 commercial banks and country-level in six ASEAN countries from 2008 to 2019, we perform the multivariate regression analysis and provide a variety of robustness tests. Results: Our empirical evidence shows the volatility of foreign portfolio investments has significantly negative effect on the banking stability, besides that of foreign other investments has the similar influence but the result is relatively less pronounced in some robustness tests. Additionally, increasing trade cooperation and international distribution may lead countries to face higher risk of banking instability driven from these international investments. Meanwhile, the impact of foreign direct investments is positive, but the evidence is the least obvious. Conclusions: Our findings suggest policy-makers in ASEAN and emerging nations as a whole should carefully consider when building policies-related to mitigate the adverse impact of foreign capital flows.

Fine Structural Analysis of the Cocoon Silk Production in the Garden Spider, Argiope aurantia

  • Moon, Myung-Jin
    • Animal cells and systems
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    • 제7권1호
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    • pp.35-41
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    • 2003
  • The principal fibers used in constructing the cocoon in the garden spider, Argiope aurantia, are large-diameter fibers developed from tubuliform glands and small-diameter fibers presumed to be spun by the aciniform silk glands. Scanning electron micrographs of the large-diameter fibers on both surfaces of the cocoon clearly reveal their fine structural differences. While the silk fibers on the inner surface have smooth and homogeneous appearances, each fiber on the outer surface represents a multicomponent internal structure. Examination of each fibers using transmission electron microscope also provides additional evidence that the multicomponent fibers contain numerous electron lucent fibrils embedded in an amorphous electron dense matrix. It has been also revealed that two types of secretory granules presumed to be the precursors of tubuliform fibers are closely related to the production of distinct coloration in luminal contents - brownish and yellowish components. Moreover, these electron-dense granules, possibly precursor of fibrillar component, and electron-lucent granules, possibly precursor of matrix component, are densely packed and remain close to each other without fusion. It is critical evidence that the individual tubuliform fiber is not only heterogeneous and multicomponent but also takes place in a variety at manners throughout the length of the gland.

Product versus Process Innovation and the Global Engagement of Firms

  • Jang, Yong Joon;Hyun, Hea-Jung
    • Journal of Korea Trade
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    • 제25권4호
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    • pp.37-59
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    • 2021
  • Purpose - Although models of innovation and exporting dominate recent studies of relations between innovation and access to foreign markets, relations between innovation and foreign direct investment (FDI) are less explored. This is especially true of relations between types of innovation and FDI. We fill that gap in the literature with empirical evidence that clarifies whether firms enter foreign markets through exports or FDI. Design/methodology - In order to assess the role of innovation in firms' international engagement strategies, we develop research hypotheses and present new empirical evidence on firms' choice of entry - exports and FDI - based on firm-level data. Findings - Our empirical results suggest that the impact of product innovation is more significant in transition from being a purely domestic firm to an exporter, while process innovation more significantly affect transition from being an exporter to a multinational enterprise. Our results also support 'self-selection into FDI' rather than 'learning-by-performing FDI' in the relationship between innovation and firms' overseas expansion. Originality/value - Recent literature on the relationship between innovation and firms' participation in foreign markets is dominated by models of innovation and export behavior. However, foreign direct investment by multinational enterprises may also be associated with firms' innovative activities. We first analyze how product and process innovations influence firms' choices to initiate exports or FDI.

Evidential Fusion of Multsensor Multichannel Imagery

  • Lee Sang-Hoon
    • 대한원격탐사학회지
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    • 제22권1호
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    • pp.75-85
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    • 2006
  • This paper has dealt with a data fusion for the problem of land-cover classification using multisensor imagery. Dempster-Shafer evidence theory has been employed to combine the information extracted from the multiple data of same site. The Dempster-Shafer's approach has two important advantages for remote sensing application: one is that it enables to consider a compound class which consists of several land-cover types and the other is that the incompleteness of each sensor data due to cloud-cover can be modeled for the fusion process. The image classification based on the Dempster-Shafer theory usually assumes that each sensor is represented by a single channel. The evidential approach to image classification, which utilizes a mass function obtained under the assumption of class-independent beta distribution, has been discussed for the multiple sets of mutichannel data acquired from different sensors. The proposed method has applied to the KOMPSAT-1 EOC panchromatic imagery and LANDSAT ETM+ data, which were acquired over Yongin/Nuengpyung area of Korean peninsula. The experiment has shown that it is greatly effective on the applications in which it is hard to find homogeneous regions represented by a single land-cover type in training process.