• Title/Summary/Keyword: Cellular proliferation

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Effects of Zinc chloride on the Immunobiological Responses of Lipopolysaccharide (리포폴리사카라이드의 면역생물학적 반응에 미치는 염화아연의 영향)

  • 채병숙
    • YAKHAK HOEJI
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    • v.43 no.1
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    • pp.48-54
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    • 1999
  • Effects of zinc chloride (Zn) on the immune responses of lipopolysaccharide (LPS) were studied by using ICR mice. Mice were divided into 4 groups (10 mice/group), and Zn was given to the mice with i.p. injection at 0.3 mg/kg 5 times a week for 14 days, and 1 hr after Zn administration, LPS was given with i.p. injection at 5 mg/kg twice a week. Mice were immunized and challenged with sheep red blood cells (SRBC). Immunobiological responses were evaluated by humoral, cellular and nonspecific immunity. LPS treatment significantly increased the relative weights of spleen and thymus, hemagglutination titer (HA) and proliferation of splenocytes compared with those in controls, but significantly decreased the body weight gain. Zn treatment significantly increased proliferation of splenocytes and circulating leukocytes compared with those in controls. Combination of Zn and LPS significantly decreased the body weight gain and proliferation of splenocytes compared with those in controls. Combination of Zn and LPS significantly decreased HA and proliferation of splenocytes than in LPS alone. These findings indicate that zinc lowered the humoral immune responses of LPS.

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A STUDY ON THE RESPONSES OF OSTEOBLASTS TO VARIOUS SURFACE-TREATED TITANIUM

  • Lee Joung-Min;Kim Yung-Soo;Kim Chang-Whe;Jang Kyung-Soo;Lim Young-Jun
    • The Journal of Korean Academy of Prosthodontics
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    • v.42 no.3
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    • pp.307-326
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    • 2004
  • Statement of problem. The long-term success of implants is the development of a stable direct connection between bone and implant surface, which must be structural and functional. To improve a direct implant fixation to the bone, various strategies have been developed focusing on the surface of materials. Among them, altering the surface properties can modify cellular responses such as cell adhesion, cell motility and bone deposition. Purpose. This study was to evaluate the cellular behaviors on the surface-modified titanium by morphological observation, cellular proliferation and differentiation. Material and methods. Specimens were divided into five groups, depending on their surface treatment: electropolishing(EP) anoclizing(AN), machining(MA), blasting with hydroxyapatite particle(RBM) and electrical discharge machining(EDM). Physicochemical properties and microstructures of the specimens were examined and the responses of osteoblast-like cells were investigated. The microtopography of specimens was observed by scanning electron microscopy(SEM). Surface roughness was measured by a three-dimensional roughness measuring system. The microstructure was analyzed by X-ray diffractometer(XRD) and scanning auger electron microscopy(AES). To evaluate cellular responses to modified titanium surfaces, osteoblasts isolated from neonatal rat were cultured. The cellular morphology and total protein amounts of osteoblast-like cell were taken as the marker for cellular proliferation, while the expression of alkaline phosphatase was used as the early differentiation marker for osteoblast. In addition, the type I collagen production was determined to be a reliable indicator of bone matrix synthesis. Results. 1. Each prepared specimen showed specific microtopography at SEM examination. The RBM group had a rough and irregular pattern with reticulated appearance. The EDM-treated surface had evident cracks and was heterogeneous consisting of broad sheet or plate with smooth edges and clusters of small grains, deep pores or craters. 2. Surface roughness values were, from the lowest to the highest, electropolished group, anodized group, machined group, RBM group and EDM group. 3. All groups showed amorphous structures. Especially anodized group was found to have increased surface oxide thickness and EDM group had titaniumcarbide(TiC) structure. 4. Cells on electropolished, anodized and machined surfaces developed flattened cell shape and cells on RBM appeared spherical and EDM showed both. After 14 days, the cells cultured from all groups were formed to be confluent and exhibited multilayer proliferation, often overlapped or stratified. 5. Total protein amounts were formed to be quite similar among all the group at 48 hours. At 14 days, the electropolished group and the anodized group induced more total protein amount than the RBM group(P<.05). 6. There was no significant difference among five groups for alkaline phosphatase(ALP) activity at 48 hours. The AN group showed significantly higher ALP activity than any other groups at 14 days(P<.05). 7. All the groups showed similar collagen synthesis except the EDM group. The amount of collagen on the electropolished and anodized surfaces were higher than that on the EDM surface(P<.05).

Platelets Induce Proliferation of Human Umbilical Vein Endothelial Cells via CD154-CD40 Pathway Independently of VEGF

  • Cho, Wha-Jung;Ko, Eun-Mi;Cheon, In-Su;Jeoung, Doo-Il;Kim, Young-Myeong;Choe, Jong-Seon
    • IMMUNE NETWORK
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    • v.8 no.3
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    • pp.75-81
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    • 2008
  • Background: Platelets take part in repairing the lesions of endothelial damage. To understand the molecular mechanism of this process, we tested the hypothesis that CD154 expressed on activated platelets stimulates proliferation of human endothelial cells. Methods: The expression levels of CD154 and CD40 on platelets and endothelial cells, respectively, were measured by flow cytometry and confocal microscopy. Function-blocking monoclonal antibody against CD154 was developed after immunization with CD154-transfected L cells. Results: An anti-CD40 agonist antibody and soluble CD154 both induced significant proliferation of endothelial cells. In addition, a function-blocking anti-CD154 antibody inhibited the platelet-induced proliferation of endothelial cells, indicating that the CD154-CD40 pathway is involved in these cellular interactions. An anti-VEGF antibody failed to inhibit the proliferation. This, in addition to the fact that very small amounts of VEGF are released from platelets or endothelial cells, suggests that VEGF does not play an important role in the platelet-stimulated proliferation of endothelial cells. Conclusion: Our results indicate that platelets induce proliferation of endothelial cells by CD154-CD40 interactions independently of VEGF.

The Effect of a Long-Term Cyclic Strain on Human Dermal Fibroblasts Cultured in a Bioreactor on Chitosan-Based Scaffolds for the Development of Tissue Engineered Artificial Dermis

  • Lim, Sae-Hwan;Son, Young-Sook;Kim, Chun-Ho;Shin, Heung-Soo;Kim, Jong-Il
    • Macromolecular Research
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    • v.15 no.4
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    • pp.370-378
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    • 2007
  • Mechanical stimulation is known to activate several cellular signal transduction pathways, leading to the induction of signaling molecules and extracellular matrix (ECM) proteins, thereby modulating cellular activities, such as proliferation and survival. In this study, primary human dermal fibroblasts (HDFs) were seeded onto chitosan-based scaffolds, and then cultured for 3 weeks in a bioreactor under a cyclic strain of 1 Hz frequency. Compared to control samples cultured under static conditions, the application of a cyclic strain stimulated the proliferation of HDFs in I week, and by week 3 the thickness of the cell/scaffold composites increased 1.56 fold. Moreover, immunohistochemical staining of the culture media obtained from the cell/scaffold samples subjected to the cyclic strain, revealed increases in the expression and secretion of ECM proteins, such as fibronectin and collagen. These results suggest that the preconditioning of cell/scaffold composites with a cyclic strain may enhance the proliferation of HDFs, and even facilitate integration of the engineered artificial dermal tissue into the host graft site.

Overexpression of Long Non-Coding RNA HOTAIR Promotes Tumor Growth and Metastasis in Human Osteosarcoma

  • Wang, Bo;Su, Yun;Yang, Qun;Lv, Decheng;Zhang, Weiguo;Tang, Kai;Wang, Hong;Zhang, Rui;Liu, Yang
    • Molecules and Cells
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    • v.38 no.5
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    • pp.432-440
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    • 2015
  • Human osteosarcoma usually presented a high tendency to metastatic spread and caused poor outcomes, however, the underlying mechanism was still largely unknown. In the present study, using a series of in vitro experiments and an animal model, we investigated the roles of HOX antisense intergenic RNA (HOTAIR) during the proliferation and invasion of osteosarcoma. According with our results, HOTAIR was commonly overexpressed in osteosarcoma, which significantly correlated with advanced tumor stage, highly histological grade and poor prognosis. In vitro and in vivo experiments demonstrated that knockdown of HOTAIR could notably suppress cellular proliferation, inhibit invasion and decrease the secretion of MMP2 and MMP9 in osteosarcoma. Collectively, our results suggested that HOTAIR might be a potent therapeutic target for osteosarcoma.

Brazilin Augments Cellular Immunity in Multiple Low Dose Streptozotocin (MLD-STZ) Induced Type I Diabetic Mice

  • Yang, Kyoung-Mee;Jeon, Sun-Duck;So, Dhong-Soo;Moon, Chang-Kiu
    • Archives of Pharmacal Research
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    • v.23 no.6
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    • pp.626-632
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    • 2000
  • Brazilin, an active principle of Caesalprenia sappan, was examined for its immunopotentiating effects in multiple low dose streptozotocin (MLD-STZ) induced type diabetic mice. Brazilin was intraperitoneally administered for 5 consecutive days to MLD-STZ induced type 1 diabetic mice. Delayed type hypersensitivity, Con A-induced proliferation of splenocytes and mixed lymphocyte reaction, which had been decreased in diabetic mice, were significantly recovered by the administration of brazilin. Brazilin increased IL-2 production without affecting suppressor cell activity. Con A-induced and IL-2-induced expression of high affinity IL-2 receptors were also enhanced by brazilin. These results indicate that brazilin augments cellular immune responses, which are suppressed in the MLD-STZ induced type I diabetic mice, by increasing IL-2 production and responsiveness of immune cells to IL-2.

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Mammalian target of rapamycin inhibitors for treatment in tuberous sclerosis

  • Kim, Won-Seop
    • Clinical and Experimental Pediatrics
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    • v.54 no.6
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    • pp.241-245
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    • 2011
  • Tuberous sclerosis complex (TSC) is a genetic multisystem disorder that results from mutations in the TSC1 or TSC2 genes, and is associated with hamartomas in several organs, including subependymal giant cell tumors. The neurological manifestations of TSC are particularly challenging and include infantile spasms, intractable epilepsy, cognitive disabilities, and autism. The TSC1- and TSC2-encoded proteins modulate cell function via the mammalian target of rapamycin (mTOR) signaling cascade, and are key factors in the regulation of cell growth and proliferation. The mTOR pathway provides an intersection for an intricate network of protein cascades that respond to cellular nutrition, energy levels, and growth factor stimulation. In the brain, TSC1 and TSC2 have been implicated in cell body size, dendritic arborization, axonal outgrowth and targeting, neuronal migration, cortical lamination, and spine formation. The mTOR pathway represents a logical candidate for drug targeting, because mTOR regulates multiple cellular functions that may contribute to epileptogenesis, including protein synthesis, cell growth and proliferation, and synaptic plasticity. Antagonism of the mTOR pathway with rapamycin and related compounds may provide new therapeutic options for TSC patients.

In Vivo/In Vitro Properties of Novel Antioxidant Peptide from Pinctada fucata

  • Ma, Yongkai;Huang, Kehui;Wu, Yanyan
    • Journal of Microbiology and Biotechnology
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    • v.31 no.1
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    • pp.33-42
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    • 2021
  • Due to the potential of antioxidants to scavenge free radicals in human body, it is important to be able to prepare antioxidant peptides that meet the industrial requirements for cosmetics and food. Here, we determined in vivo/in vitro activities of antioxidant peptide from P. fucata (PFAOP) prepared by bio-fermentation method. The antioxidant property test results showed the DPPH, hydroxyl, superoxide radical-scavenging, and cellular antioxidant activity. EC50 values of PFAOPs were 0.018 ± 0.005, 0.126 ± 0.008, 0.168 ± 0.005, and 0.105 ± 0.005 mg/ml, respectively, exhibiting higher antioxidant activities than glutathione (p < 0.05). Moreover, anti-proliferation and cytotoxicity activity results illustrated PFAOP has a potent anti-proliferative activity against HepG2, Caco-2, and MCF-7 carcinoma cells with no cytotoxicity. Moreover, the protocols we developed in this work demonstrated several excellent advantages in PFAOP preparation compared to enzymatic hydrolysis or chemical synthesis methods and provide a theoretical foundation for higher-value application of marine-derived functional peptides.

Zinc may increase bone formation through stimulating cell proliferation, alkaline phosphatase activity and collagen synthesis in osteoblastic MC3T3-E1 cells

  • Seo, Hyun-Ju;Cho, Young-Eun;Kim, Tae-Wan;Shin, Hong-In;Kwun, In-Sook
    • Nutrition Research and Practice
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    • v.4 no.5
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    • pp.356-361
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    • 2010
  • Zinc is an essential trace element required for bone formation, however not much has been clarified yet for its role in osteoblast. We hypothesized that zinc would increase osteogenetic function in osteoblasts. To test this, we investigated whether zinc treatment enhances bone formation by stimulating osteoblast proliferation, bone marker protein alkaline phosphatase activity and collagen synthesis in osteoblastic MC3T3-E1 cells. MC3T3-E1 cells were cultured and treated with various concentrations of zinc (0, 1, 3, 15, 25 uM) along with a normal osteogenic medium (OSM) as control for 1, 5, 10 days. As measured by MTT assay for mitochondrial metabolic activity, cell proliferation was stimulated even at low zinc treatment (1-3 ${\mu}M$) compared to OSM, and it was stimulated in a zinc concentration-dependent manner during 5 and 10 days, with the most pronounced effect at 15 and 25 uM Zn. Cellular (synthesized) alkaline phosphatase (ALP) activity was increased in a zinc concentration-dependent manner, so did medium (secreted) ALP activity. Cellular collagen concentration was increased by zinc as time went by, therefore with the maximum zinc stimulatory effect in 10 days, and medium collagen concentration showed the same pattern even on 1 and 5 day. This zinc stimulatory effect of collagen synthesis was observed in cell matrix collagen staining. The study results imply that zinc can increase osteogenic effect by stimulating cell proliferation, ALP activity and collagen synthesis in osteoblastic cells.

Effects of Salviae miltiorrhizae Radix Extract on Gene Expression of Dendritic cells. (단삼이 수지상 세포의 유전자 발현에 미치는 영향)

  • Chiang, Wen-Lih;Kim, Jong-Han;Choi, Jeong-Hwa;Park, Su-Yeon
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.21 no.3
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    • pp.52-68
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    • 2008
  • Objectives and Methods : Salviae miltiorrhizae Radix (SMR) promotes blood circulation to remove blood stasis, cools the blood to relieve carbuncle, clears away heat from the heart and tranquilizes the mind. This study was designed to investigate the effects of SMR on immuno-potentiative action in terms of changes in the genetic profile of dendritic cells (DC) using by microarray analysis. Results and Conclusion: In this experiment, treatments with more than 250 ${\mu}g/ml$ upto 1000 ${\mu}g/ml$ of SMR elevated the proliferation rates of DC. Microscopic observations confirmed the tendency on proliferation rates. Expression levels of genes related with cellular methabolic process, cell communication, and macromolecule metabolic process were elevated by treatment with SMR in comparison of functional distribution in a Biological Process. In molecular functions, expression levels of genes related with receptor activation, nucleotide binding and nucleic acid binding were elevated. In cellular components, expression levels of genes related to cellular membrane-bound organelles were elevated. In addition, expression levels of genes related to Wnt signalling pathways and the glycerophospholipid metabolism were elevated through analysis using pathway analysis between up-and down-regulated genes in cells treated with SMR. Finally, genes related to JAK2, GRB2, CDC42, SMAD4, B2M, FOS and ESRI located the center of Protein interaction network of genes through treatment with SMR.

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