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Culture Polystyrene (culture + polystyrene)
Kinds of Culture Polystyrene Selected AbstractsA New Approach for Adipose Tissue Regeneration Based on Human Mesenchymal Stem Cells in Contact to Hydrogels,an In Vitro Study,ADVANCED ENGINEERING MATERIALS, Issue 10 2009Kirsten Peters In this study an approach for adipose tissue regeneration based on human mesenchymal stem cells and hydrogels as supporting matrix was evaluated. The gelatin-based hydrogels developed in this study were cytocompatible and stem cell adhesion onto hydrogel surfaces was higher as compared to tissue culture polystyrene. Furthermore, the adipogenic differentiation degree was increased. These results are promising for future applications of hydrogels in adipose tissue regeneration strategies. [source] Substrate adhesion affects contraction and mechanical properties of fibroblast populated collagen latticesJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 1 2008Meng-Yi Chen Abstract Fibroblasts can condense a hydrated collagen lattice to a tissue-like structure. The purpose of this study was to evaluate the effect of substrate adhesion on the contraction and mechanical properties of fibroblast populated collagen lattices. Bacteriological grade polystyrene (BGPS) plates and tissue culture polystyrene (TCPS) plates were used as substrates for incubation of fibroblast populated collagen lattices. Hydrophobicity of the polystyrene surfaces was measured by the static sessile contact angle method. Collagen lattice contraction was recorded for 2 weeks, after which the lattices were mechanically tested. The BGPS culture plate had a significantly larger contact angle and was more hydrophobic than the TCPS culture plate. Both hydrophobicity and peripheral detachment of the collagen gel significantly decreased the time lag before initiation of gel contraction and increased the strength of the fibroblast populated collagen lattices. Substrate adhesion affects the contractility and strength of cell seeded collagen gels. This information may be useful in developing tissue engineered tendons and ligaments. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 2008 [source] Intracellular signaling involved in macrophage adhesion and FBGC formation as mediated by ligand,substrate interactionJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 4 2002Weiyuan John Kao Abstract Fibronectin and RGD- and/or PHSRN-containing oligopeptides were preadsorbed onto physicochemically distinct substrata: polyethyleneglycol-based networks or tissue culture polystyrene (TCPS). The role of selected signaling kinases (namely protein tyrosine kinases, protein serine/threonine kinases, PI3-kinase, Src, and MAPK) in the adhesion of human primary blood-derived macrophages and the formation of foreign-body giant cells (FBGC) on these modified substrata was investigated. The involvement of individual intracellular signaling molecules in mediating macrophage adhesion dynamically varied with the culture time, substrate, and ligand. For example, fibronectin on TCPS or networks involved similar signaling events for macrophage adhesion; however, fibronectin and G3RGDG6PHSRNG, but not peptides with other RGD and/or PHSRN orientations, mediated similar signaling events for macrophage adhesion on TCPS but mediated different signaling events on networks. Depending on the substrate, a specific molecule (i.e., Src, protein kinase C) within the protein tyrosine kinase or protein serine/threonine kinase family was either an antagonist or agonist in mediating FBGC formation. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res 62: 478,487, 2002 [source] The regulation of osteogenesis by ECM rigidity in MC3T3-E1 cells requires MAPK activationJOURNAL OF CELLULAR PHYSIOLOGY, Issue 3 2007Chirag B. Khatiwala Once thought to provide only structural support to tissues by acting as a scaffold to which cells bind, it is now widely recognized that the extracellular matrix (ECM) provides instructive signals that dictate cell behavior. Recently we demonstrated that mechanical cues intrinsic to the ECM directly regulate the behavior of pre-osteoblastic MC3T3-E1 cells. We hypothesized that one possible mechanism by which ECM compliance exerts its influence on osteogenesis is by modulating the mitogen-activated protein kinase (MAPK) pathway. To address this hypothesis, the differentiation of MC3T3-E1 cells cultured on poly(ethylene glycol) (PEG)-based model substrates with tunable mechanical properties was assessed. Alkaline phosphatase (ALP) levels at days 7 and 14 were found to be significantly higher in cells grown on stiffer substrates (423.9 kPa hydrogels and rigid tissue culture polystyrene (TCPS) control) than on a soft hydrogel (13.7 kPa). Osteocalcin (OCN) and bone sialoprotein (BSP) gene expression levels followed a similar trend. In parallel, MAPK activity was significantly higher in cells cultured on stiffer substrates at both time points. Inhibiting this activation pharmacologically, using PD98059, resulted in significantly lower ALP levels, OCN, and BSP gene expression levels on the hydrogels. Interestingly, the effectiveness of PD98059 was itself dependent on substrate stiffness, with marked inhibition of MAPK phosphorylation in cells grown on compliant hydrogels but insignificant reduction in cells grown on TCPS. Together, these data confirm a role for MAPK in the regulation of osteogenic differentiation by ECM compliance. J. Cell. Physiol. 211: 661,672, 2007. © 2007 Wiley-Liss, Inc. [source] Ceric Ammonium Nitrate Initiated Grafting of PEG to Plasma Polymers for Cell-Resistant SurfacesPLASMA PROCESSES AND POLYMERS, Issue 2 2008Naomi J. Vickers Abstract The development of a facile method with general applicability and mild reaction conditions for grafting PEG onto surfaces to reduce bio-adhesion is described. The approach taken was to use CAN to graft PEG to plasma polymers coatings selected to give a high concentration of alcohol groups. The study showed that grafting required functional groups on surfaces, a minimum concentration of CAN initiator (0.05 M) and was time and initiator concentration dependent. Adhesion of fibroblasts and endothelial cells was reduced to negligible levels compared to the adhesion to tissue culture polystyrene and untreated plasma polymers of allyl alcohol following CAN induced PEG grafting. [source] Biodegradation and Biocompatibility of PolyorganophosphazeneARTIFICIAL ORGANS, Issue 10 2002Hiroyoshi Kawakami Abstract: We investigated biodegradation and biocompatibility of poly(organophosphazenes). We prepared poly(organophosphazenes) having different side chain groups. The blood compatibility of poly(organophosphazenes) containing fluorinated side groups, poly(bis[trifluoroethoxy]phosphazene) (PbFP) and poly([trifluoroethoxy][ethyl glycinate]phosphazene) (PFGP), without heparinization were evaluated in vitro. The deformation and aggregation of platelets adhered on PbFP and PFGP were not observed and they suppressed platelet activation. Additionally, PbFP and PFGP showed a higher degradation rate, despite their high hydrophobic nature. We found that the high mobility of water in PbFP and PFGP was one of the important factors facilitating their degradation. Their polymer structures were formed in a more open nature, indicating that water easily attacked the backbone of the phosphorus and nitrogen atoms in the poly(organophosphazene). On the other hand, the proliferation of HeLa cells cultured on poly(organophosphazene) was reduced compared with that on the control tissue culture polystyrene. [source] Novel ceramic bone replacement material CeraBall® seeded with human mesenchymal stem cellsCLINICAL ORAL IMPLANTS RESEARCH, Issue 3 2010Timothy Douglas Abstract Objectives: Hydroxyapatite (HA) and tricalcium phosphate (TCP) are two very common ceramic materials for bone replacement. A recently developed material for bone replacement is CeraBall®, which is a mixed HA,TCP scaffold available as porous spherical scaffolds of diameter 4 and 6 mm. Before their use as bone replacement materials in vivo, in vitro testing of these scaffolds is necessary. The goal of this study was to characterise 4 and 6 mm CeraBall® scaffolds in vitro with a view to their future use as bone replacement materials. Materials and methods: The proliferation of human mesenchymal stromal cells (hMSCs) seeded on CeraBall® scaffolds was evaluated quantitatively using the WST [Water soluble tetrazolium ((4-[3-(4- Iodophenyl)-2-(4-nitrophenyl)-2H-5-tetrazolio]-1, 3-benzene disulfonate)] test and qualitatively by scanning electron microscopy (SEM). In addition, the standard MTT [(3-(4, 5-Dimenthylthiazol-2-Y1)-2, 5-Diphenyltetrazolium bromide)] biocompatibility test and cell vitality staining were performed using hMSCs. CeraBall® scaffolds were also tested for their mechanical properties. Results: SEM and WST test results showed that hMSCs proliferated on CeraBall® scaffolds over the course of 9 days. Proliferation was similar to that seen on tissue culture polystyrene (control). Cells showed a well-spread morphology and formed ,sheets' on the surface of scaffolds. Invasion of pores was observed. Good biocompatibility was demonstrated by MTT test results and cell vitality staining. Scaffolds of both 4 and 6 mm were able to withstand compressive loads of 5 N. Conclusions: CeraBall® scaffolds show good biocompatibility in vitro for hMSCs. This opens the way for in vivo applications. To cite this article: Douglas T, Liu Q, Humpe A, Wiltfang J, Sivananthan S, Warnke PH. Novel ceramic bone replacement material CeraBall® seeded with human mesenchymal stem cells. Clin. Oral Impl. Res. 21, 2010; 262,267. doi: 10.1111/j.1600-0501.2009.01818.x [source] | |||||||||||||