• Title/Summary/Keyword: non-proliferation

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Rx for Tissue Restoration: Regenerative Biology and Medicine

  • Stocum, David L.
    • Animal cells and systems
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    • v.5 no.2
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    • pp.91-99
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    • 2001
  • Vertebrates regenerate tissues in three ways: proliferation of cells that maintain some or all of their differentiated structure and function, redifferentiation of mature cells followed by proliferation and redifferentiation into the same cell type or transdetermination to another cell type, and activation of restricted lineage stem cells, which have the ability to transdetermine to different lineages under the appropriate conditions. The behavior of the cells during regeneration is regulated by growth factors and extracellular matrix molecules. Some non-regenerating tissues are now known to harbor stem cells which, though they form scar tissue in vivo, are capable of producing new tissue-specific cells in vitro, suggesting that the injury environment inhibits latent regenerative capacity. Regenerative medicine seeks to restore tissues via transplantation of stem cell derivatives, implantation of bioartificial tissues, or stimulation of regeneration in vivo. These approaches have been partly successful, but several research issues must be addressed before regenerative medicine becomes a clinical reality.

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Inhibitory effects of the stem bark extract of Eucommia ulmoides on the proliferation of human tumor cell lines

  • Choi, Yeon-Hee;Seo, Jee-Hee;Kim, Jung-Sook;Kim, Seong-Kie;Choi, Sang-Un;Kim, Young-Sup;Kim, Young-Kyoon;Ryu, Shi-Yong
    • Proceedings of the PSK Conference
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    • 2003.10b
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    • pp.190.1-190.1
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    • 2003
  • A bioassay-guided fractionation of the stem bark extract of Eucommia ulmoides Oliver (Eucommiaceae) led to the isolation of three iridoid constituents, genipin (1), geniposide (3), geniposidic acid (4) as well as (${\pm}$)-guaiacylglycerol (2) and fatty acid mixtures as active ingredients of the extract responsible for the antitumoral property. The EtOAc soluble part and BuOH soluble part of the extract demonstrated a significant inhibition on the proliferation of cultured human tumor cells such as A549 (non small cell lung), SK-OV-3 (ovary), SK-MEL-2 (melanoma), XF498 (central nerve system) and HCT-15 (colon) in vitro, whereas the remaining water soluble part exhibited a poor inhibition. (omitted)

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Inhibitory effects of the extract of Viscum album on the proliferation of human tumor cell lines

  • Seo, Jee-Hee;Choi, Yeon-Hee;Kim, Jung-Sook;Kim, Seong-Kie;Choi, Sang-Un;Kim, Young-Sup;Ryu, Shi-Yong;Kim, Young-Kyoon
    • Proceedings of the PSK Conference
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    • 2003.10b
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    • pp.202.2-202.2
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    • 2003
  • A bioassay-guided fractionation of the whole extract of Viscum album (a parasitic plant : Loranthaceae) led to the isolation of two triterpenoidal components, oleanolic acid (1), ${\beta}$-amyrin acetate (2), homoflavoyadorinin B (3) as well as large quantity of free fatty acid mixtures as active ingredients of the extract responsible for the antitumoral property. The EtOAc soluble part and BuOH soluble part of the extract demonstrated a significant inhibition on the proliferation of cultured human tumor cells such as A549 (non small cell lung), SK-OV-3 (ovary), SK-MEL-2 (melanoma), XF498 (central nerve system) and HCT-15 (colon) in vitro, whereas the remaining water soluble part exhibited a poor inhibition. (omitted)

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Effect of Photobiomodulation on the Mesenchymal Stem Cells

  • Yoo, Shin Hyuk
    • Medical Lasers
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    • v.9 no.2
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    • pp.119-125
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    • 2020
  • Photobiomodulation forms the basis of photomedicine and is defined as the effect of coherent or non-coherent light sources, such as low-level lasers and light-emitting diodes, on cells and tissues. This treatment technique affects cell functions, proliferation, and migration, and plays an important role in tissue regeneration. Mesenchymal stem cells (MSCs) are known to be beneficial for tissue regeneration, and the combination of stem cell therapy and laser therapy appears to positively affect treatment outcomes. In general, a low-power laser has a positive effect on MSCs, thereby facilitating improvements in different disease models. This study elucidates the mechanisms and effects of low-power laser irradiation on the proliferation, migration, and differentiation of various MSCs that have been examined in different studies.

Immunoregulatory Action of Soeumin Seungyangikkitang (소음인(少陰人) 승양익기탕(升陽益氣湯)의 면역조절작용(免疫調節作用))

  • Ryu, Chang-ryeol;Song, Jeong-mo
    • Journal of Sasang Constitutional Medicine
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    • v.13 no.3
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    • pp.102-113
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    • 2001
  • The purpose of this research was to investigate the effects of Seungyangikkitang (SIT) on the immune cells in BALB/c mice. SIT (500mg/kg) was administerd p.o. once a day for 7 days. SIT enhanced the proliferation of thymocytes, but decreased the proliferation of splenocytes. SIT enhanced the subpopulation of cytotoxic T cells in thymocytes and helper T cells in splenocytes, but did not affect the subpopulation of B220/Thy1 cells. SIT enhanced the production of γ-interferon and interleukin-2 in thymocytes, splenocytes and serum, but did not affect the production of interleukin-4. SIT suppressed the production of nitric oxide, but enhanced the lucigenin chemiluminescence and the engulfment of FITC-conjugated E. coli particles in peritoneal macrophages. These results suggest that SIT has a potent activity on the specific immunity via the cytokine secretion of Th1 cells and the non-specific immunity via the phagocytic activity of macrophages in vivo.

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An Analysis of Constraints on Pyroprocessing Technology Development in ROK Under the US Nonproliferation Policy

  • Jae Soo Ryu
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.21 no.3
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    • pp.383-395
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    • 2023
  • Since 1997, the Republic of Korea (ROK) has been developing pyro-processing (Pyro) technology to reduce the disposal burden of high-level radioactive waste by recycling spent nuclear fuel (SNF). Compared to plutonium and uranium extraction process, Korean Pyro technology has relatively excellent proliferation resistance that cannot separate pure plutonium owing to its intrinsic characteristics. Regarding Pyro technology development of ROK, the Bush administration considered that Pyro is not reprocessing under the Global Nuclear Energy Partnership, whereas the Obama administration considered that Pyro is subject to reprocessing. However, the Bush and Obama administrations did not allow ROK to conduct full Pyro activities using SNF, even though ROK had faithfully complied with international nonproliferation obligations. This is because the US nuclear nonproliferation policy to prevent the spread of sensitive technologies, such as enrichment and reprocessing, has a strong effect on ROK, unlike Japan, on a bilateral level beyond the NPT regime for non-proliferation of nuclear weapons.

Circular RNA hsa_circ_0075828 promotes bladder cancer cell proliferation through activation of CREB1

  • Zhuang, Chengle;Huang, Xinbo;Yu, Jing;Gui, Yaoting
    • BMB Reports
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    • v.53 no.2
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    • pp.82-87
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    • 2020
  • Circular RNAs (circRNAs), one kind of non-coding RNA, have been reported as critical regulators for modulating gene expression in cancer. In this study, microarray analysis was used to screen circRNA expression profiles of bladder cancer (BC) 5637 cells, T24 cells and normal control SV-HUC-1 cells. The data from the microarray showed that hsa_circ_0075828 (named circCASC15) was most highly expressed in 5637 and T24 cells. circCASC15 was highly expressed in BC tissues and cells. Overexpression of circCASC15 was closely associated with BC tumor stage and promoted cell proliferation significantly in vitro and in vivo. Mechanistically, circCASC15 could act as miR-1224-5p sponge to activate the expression of CREB1 to promote cell proliferation in BC. In short, circCASC15 promotes cell proliferation in BC, which might be a new molecular target for BC diagnosis and therapy.

The protective effect of coenzyme Q10 on cytotoxicity of regin monomer of odontoblast caused by TEGDMA (코엔자임 Q10 처리에 따른 TEGDMA에 의해 유발된 치아 세포 사멸 억제 효과)

  • Lee, Ahreum;Park, Soyeong;Lee, Kyung Hee
    • Journal of Korean society of Dental Hygiene
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    • v.14 no.5
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    • pp.775-781
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    • 2014
  • Objectives : The purpose of the study is to investigate the protective effect of coenzyme $Q_{10}$ on cytotoxicity effect of dental monomers in odontoblast(MDPC-23). Methods : MDPC-23 was incubated with the(co)monomers triethylene glycol dimethacrylate (TEGDMA) with and without addition of coenzyme $Q_{10}$. The cell proliferation and survival was determined using WST-1 assay. The level of reactive oxygen species(ROS) was measured by immunofluorescent staining for DCF-DA. Results : TEGDMA treatment decreased the cell proliferation by dose dependently(0.1, 1, 2.5, 5, 10 mM) on the growth of MDPC-23 cells. Coenzyme $Q_{10}$ showed cell proliferation from 5 to $500{\mu}M$ by WST-1 assay. Pre-treatment coenzyme $Q_{10}$ showed the antioxidant effect on proliferation and viability of MDPC-23 after 48h(p<0.05). The positive cells were observed in non-coenyme $Q_{10}$ treatment group(group 2) in comparison with coenyme $Q_{10}$ pre-treatment group(group 1) by DCF-DA. The fluorescence positive cells showed 14.715(group 1) and 19.788(group 2) using image J system. Conclusions : TEGDMA induced cytotoxicity. The MDPC-23 cell death was associated with the increasing ROS. Coenyme $Q_{10}$ showed the antioxidant effects by decreasing ROS. This effects may contribute to the treatment of periodontal disease induced by TEGDMA after operation.

Effects of Suspension Culture on Proliferation and Undifferentiation of Spermatogonial Stem Cells Derived from Porcine Neonatal Testis

  • Park, Min Hee;Park, Ji Eun;Kim, Min Seong;Lee, Kwon Young;Yun, Jung Im;Choi, Jung Hoon;Lee, Eunsong;Lee, Seung Tae
    • Reproductive and Developmental Biology
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    • v.38 no.2
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    • pp.85-91
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    • 2014
  • Despite many researches related with in-vitro culture of porcine spematogonial stem cells (SSCs), adherent culture system widely used has shown a limitation in the maintenance of porcine SSC self-renewal. Therefore, in order to overcome this obstacle, suspension culture, which is known to have numerous advantage over adherent culture, was applied to the culture of porcine SSCs. Porcine SSCs retrieved from neonatal testes were suspension-cultured for 5 days or 20 days, and characteristics of suspension-cultured porcine SSCs including proliferation, alkaline phosphatase (AP) activity, and self-renewal-specific gene expression were investigated and compared with those of adherent-cultured porcine SSCs. As the results, the suspension-cultured porcine SSCs showed entirely non-proliferative and significantly higher rate of AP-positive cells and expression of self-renewal-specific genes than the adherent-cultured porcine SSCs. In addition, long-term culture of porcine SSCs in suspension condition induced significant decrease in the yield of AP staining-positive cells on post-day 10 of culture. These results showed that suspension culture was inappropriate to culture porcine SSCs, because the culture of porcine SSCs in suspension condition didn't stimulate proliferation and maintain AP activity of porcine SSCs, regardless of culture periods.

Preparation of Microspheres Encapsulating a Recombinant TIMP-1 Adenovirus and their Inhibition of Proliferation of Hepatocellular Carcinoma Cells

  • Xia, Dong;Yao, Hui;Liu, Qing;Xu, Liang
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.12
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    • pp.6363-6368
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    • 2012
  • Objective: The study aim was to prepare poly-DL-lactide-poly (PELA) microspheres encapsulating recombinant tissue inhibitors of metalloproteinase-1 (TIMP-1) in an adenovirus to investigate its inhibition on the proliferation of hepatocellular carcinoma cells HepG2. Methods: Microspheres were prepared by encapsulating the recombinant TIMP-1 adenovirus into biodegradable PELA. The particle size, viral load, encapsulation efficiency and in-vitro release were measured. Microspheres were used to infect HepG2 cells, then infection efficiency was examined under a fluorescent microscope and ultrastructural changes assessed by TEM. Expression of TIMP-1 mRNA in HepG2 cells was examined by semi-quantitative RT-PCR and proliferation by MTT and cell growth curve assays. Results: We successfully prepared microspheres encapsulating recombinant TIMP-1 adenovirus with a diameter of $1.965{\mu}m$, an encapsulation efficiency of 60.0%, a viral load of $10.5{\times}10^8/mg$ and approximate 60% of virus release within 120 h, the total releasing time of which was longer than 240 h. The microspheres were confirmed to be non-toxic with blank microspheres. Infected HepG2 cells could stably maintain in-vitro expression of TIMP-1, with significantly effects on biological behaviour Conclusion: PELA microspheres encapsulating a recombinant TIMP-1 adenovirus can markedly inhibit the proliferation of HepG2 cells, which provides an experimental basis for polymer/chemistry-based gene therapy of hepatocellular carcinomas.