• Title/Summary/Keyword: Cellular growth

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Anti-mycobacterial Effects of the Extract of Humulus japonicus (환삼덩굴(Humulus japonicus) 추출물의 항결핵 효과)

  • Hong, Min-Sun;Son, Eun-Soon;Lee, Sung-Joong;Lee, Sun-Kyoung;Lee, Ye-Jin;Song, Sun-Dae;Cho, Sang-Nae;Barry, Clifton E. III;Eum, Seok-Yong
    • Korean Journal of Food Science and Technology
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    • v.46 no.1
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    • pp.94-99
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    • 2014
  • The present study aimed to evaluate the in vitro antimycobacterial effects of hop plant, Humulus japonicus. Methanol extract of H. japonicus (MeOH extract) showed strong direct bactericidal effects against Mycobacterium tuberculosis in vitro. Furthermore, the MeOH extract significantly inhibited M. tuberculosis growth in human macrophages. When five fractions obtained from MeOH extract were examined using the same methods, the hexane and ethyl acetate fractions showed bactericidal effects against M. tuberculosis in vitro, whereas the butanol and water fractions inhibited M. tuberculosis growth in macrophages. Because H. japonicus extract exhibited antimycobacterial activity against both free M. tuberculosis in culture medium and intracellular M. tuberculosis in human macrophages, this plant might be a good candidate for development of a new anti-tuberculosis drug.

Renal fibrosis

  • Cho, Min-Hyun
    • Clinical and Experimental Pediatrics
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    • v.53 no.7
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    • pp.735-740
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    • 2010
  • Renal fibrosis, characterized by tubulointerstitial fibrosis and glomerulosclerosis, is the final manifestation of chronic kidney disease. Renal fibrosis is characterized by an excessive accumulation and deposition of extracellular matrix components. This pathologic result usually originates from both underlying complicated cellular activities such as epithelial-to-mesenchymal transition, fibroblast activation, monocyte/macrophage infiltration, and cellular apoptosis and the activation of signaling molecules such as transforming growth factor beta and angiotensin II. However, because the pathogenesis of renal fibrosis is extremely complicated and our knowledge regarding this condition is still limited, further studies are needed.

Cellular origin of liver cancer stem cells (간암 줄기세포의 기원)

  • Eun, Jong Ryeol
    • Journal of Yeungnam Medical Science
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    • v.32 no.1
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    • pp.1-7
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    • 2015
  • Over several decades, a hierarchical cancer stem cell (CSC) model has been established in development of solid cancers, including hepatocellular carcinoma(HCC). In terms of this concept, HCCs originate from liver CSCs. Clinically HCCs show a wide range of manifestations from slow growth to very aggressive metastasis. One of the reasons may be that liver CSCs originate from different cells. This review describes the basic concept of CSCs and the cellular origin of liver CSCs.

A case study on the use of Ortho-Cellular Nutrition Therapy (OCNT) in patients with alopecia (세포교정영양요법(OCNT)을 이용한 탈모 환자 개선 사례 연구)

  • Jungmee Park
    • CELLMED
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    • v.13 no.13
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    • pp.50.1-50.5
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    • 2023
  • Objective: A case study on improvement of alopecia through OCNT. Methods: 62-year-old woman suffering from alopecia symptoms and thinning hair due to stress and overwork after her marriage. Results: Hair got thicker following the implementation of nutrition therapy with improvement of alopecia symptoms at the crown and lateral aspects of the head. Conclusion: Nutrition therapy can be helpful in promoting hair growth and increase in hair thickness for patients displaying alopecia symptoms.

Cellular Traffic Offloading through Opportunistic Communications Based on Human Mobility

  • Li, Zhigang;Shi, Yan;Chen, Shanzhi;Zhao, Jingwen
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.3
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    • pp.872-885
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    • 2015
  • The rapid increase of smart mobile devices and mobile applications has led to explosive growth of data traffic in cellular network. Offloading data traffic becomes one of the most urgent technical problems. Recent work has proposed to exploit opportunistic communications to offload cellular traffic for mobile data dissemination services, especially for accepting large delayed data. The basic idea is to deliver the data to only part of subscribers (called target-nodes) via the cellular network, and allow target-nodes to disseminate the data through opportunistic communications. Human mobility shows temporal and spatial characteristics and predictability, which can be used as effective guidance efficient opportunistic communication. Therefore, based on the regularity of human mobility we propose NodeRank algorithm which uses the encounter characteristics between nodes to choose target nodes. Different from the existing work which only using encounter frequency, NodeRank algorithm combined the contact time and inter-contact time meanwhile to ensure integrity and availability of message delivery. The simulation results based on real-world mobility traces show the performance advantages of NodeRank in offloading efficiency and network redundant copies.

Control of Singlet Oxygen-induced Oxidative Damage in Escherichia coli

  • Kim, Sun-Yee;Kim, Eun-Ju;Park, Jeen-Woo
    • BMB Reports
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    • v.35 no.4
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    • pp.353-357
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    • 2002
  • Singlet oxygen ($^1O_2$) is highly reactive form of molecular oxygen that may harm living systems by oxidizing critical cellular macromolecules. The oxyR gene product regulates the expression of the enzymes and proteins that are needed for cellular protection against oxidative stress. In this study, the role of oxyR in cellular defense against a singlet oxygen was investigated using Escherichia coli oxyR mutant strains. Upon exposure to methylene blue and visible light, which generates singlet oxygen, the oxyR overexpression mutant was much more resistant to singlet oxygen-mediated cellular damage when compared to the oxyR deletion mutant in regard to growth kinetics, viability and protein oxidation. Induction and inactivation of major antioxidant enzymes, such as superoxide desmutase and catalase, were observed after their exposure to a singlet oxygen generating system in both oxyR strains. However, the oxyR overexpression mutant maintained significantly higher activities of anticxidant enzymes than did the oxyR deletion mutant. These results suggest that the oxyR regulon plays an important protective role in singlet oxygen-mediated cellular damage, presumably through the protection of antioxidant enzymes.

Senolytics and Senostatics: A Two-Pronged Approach to Target Cellular Senescence for Delaying Aging and Age-Related Diseases

  • Kang, Chanhee
    • Molecules and Cells
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    • v.42 no.12
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    • pp.821-827
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    • 2019
  • Aging is the most important single risk factor for many chronic diseases such as cancer, metabolic syndrome, and neurodegenerative disorders. Targeting aging itself might, therefore, be a better strategy than targeting each chronic disease individually for enhancing human health. Although much should be achieved for completely understanding the biological basis of aging, cellular senescence is now believed to mainly contribute to organismal aging via two independent, yet not mutually exclusive mechanisms: on the one hand, senescence of stem cells leads to exhaustion of stem cells and thus decreases tissue regeneration. On the other hand, senescent cells secrete many proinflammatory cytokines, chemokines, growth factors, and proteases, collectively termed as the senescence-associated secretory phenotype (SASP), which causes chronic inflammation and tissue dysfunction. Much effort has been recently made to therapeutically target detrimental effects of cellular senescence including selectively eliminating senescent cells (senolytics) and modulating a proinflammatory senescent secretome (senostatics). Here, we discuss current progress and limitations in understanding molecular mechanisms of senolytics and senostatics and therapeutic strategies for applying them. Furthermore, we propose how these novel interventions for aging treatment could be improved, based on lessons learned from cancer treatment.

Epigenetic memory in gene regulation and immune response

  • Kim, Min Young;Lee, Ji Eun;Kim, Lark Kyun;Kim, TaeSoo
    • BMB Reports
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    • v.52 no.2
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    • pp.127-132
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    • 2019
  • Cells must fine-tune their gene expression programs for optimal cellular activities in their natural growth conditions. Transcriptional memory, a unique transcriptional response, plays a pivotal role in faster reactivation of genes upon environmental changes, and is facilitated if genes were previously in an active state. Hyper-activation of gene expression by transcriptional memory is critical for cellular differentiation, development, and adaptation. TREM (Transcriptional REpression Memory), a distinct type of transcriptional memory, promoting hyper-repression of unnecessary genes, upon environmental changes has been recently reported. These two transcriptional responses may optimize specific gene expression patterns, in rapidly changing environments. Emerging evidence suggests that they are also critical for immune responses. In addition to memory B and T cells, innate immune cells are transcriptionally hyperactivated by restimulation, with the same or different pathogens known as trained immunity. In this review, we briefly summarize recent progress in chromatin-based regulation of transcriptional memory, and its potential role in immune responses.

Dynamics of ARF regulation that control senescence and cancer

  • Ko, Aram;Han, Su Yeon;Song, Jaewhan
    • BMB Reports
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    • v.49 no.11
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    • pp.598-606
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    • 2016
  • ARF is an alternative reading frame product of the INK4a/ARF locus, inactivated in numerous human cancers. ARF is a key regulator of cellular senescence, an irreversible cell growth arrest that suppresses tumor cell growth. It functions by sequestering MDM2 (a p53 E3 ligase) in the nucleolus, thus activating p53. Besides MDM2, ARF has numerous other interacting partners that induce either cellular senescence or apoptosis in a p53-independent manner. This further complicates the dynamics of the ARF network. Expression of ARF is frequently disrupted in human cancers, mainly due to epigenetic and transcriptional regulation. Vigorous studies on various transcription factors that either positively or negatively regulate ARF transcription have been carried out. However, recent focus on posttranslational modifications, particularly ubiquitination, indicates wider dynamic controls of ARF than previously known. In this review, we discuss the role and dynamic regulation of ARF in senescence and cancer.

Quorum Sensing of Rhodobacter sphaeroides Negatively Regulates Cellular Poly-$\beta$-Hydroxybutyrate Content Under Aerobic Growth Conditions

  • Lee, Jeong-K.;Kho, Dhong-Hyo;Jang, Ji-Hee;Kim, Hye-Sun;Kim, Kun-Soo
    • Journal of Microbiology and Biotechnology
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    • v.13 no.3
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    • pp.477-481
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    • 2003
  • The community escape response of Rhodobacter sphaeroides is exerted through the action of CerR and CerI, which code for a LuxR-type regulatory protein and acylhomoserine lactone synthase, respectively. Deletion of chromosomal DNA including cerR and cerI (mutant RI) or insertional interruption of cert (mutant AP3) resulted in two-fold increase in the cellular poly-${\beta}$-hydroxybutyrate (PHB) content In comparison with the wild-type under aerobic growth conditions. The PHB synthase (PhbC) activities of the cer mutants were doubled, and the enzyme expression was regulated at the level of phbC transcription. Thus, CerR, possibly in response to autoinducer (AI), appears to modulate the PHB content of aerobically grown cells by downregulating phbC transcription.