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Murine Fibroblasts (murine + fibroblast)
Selected AbstractsDevelopment of spray- and freeze-dried high-concentration sesamol emulsions and antioxidant evaluation in fibroblasts and UV-exposed rat skin slicesDRUG DEVELOPMENT RESEARCH, Issue 5 2008Juliana Alencar Abstract Dry sesamol emulsions were synthesized from several combinations of saccharose with hydroxypropylmethylcellulose (HPMC) or sodium caseinate (SC) using spray-drying techniques at 120° to 180°C, or freeze-drying. On the basis of physical characteristics such as droplet size distribution, residual moisture, and microscopic structure, the best material was obtained when spray-drying was applied at either 150° or 180°C with SC or HPMC as excipients, respectively. The extent to which the antioxidant properties of free sesamol towards a set of free radicals (galvinoxyl, diphenylpicrylhydrazyl, superoxide, and hydroxyl) were altered in the starting and reconstituted liquid emulsions submitted to normal storage or pre-exposed to a flux hydroxyl radicals was investigated. Emulsions were further evaluated for their antioxidant properties in cultured 3T3 murine fibroblasts and in an ex vivo model of ultraviolet irradiated rat skin. It was found that, in the material having the best physical properties, encapsulation was decisive in: (1) improving the overall antioxidant behavior of reconstituted versus starting liquid emulsions: (2) sparing sesamol consumption due to free radical attack; and (3) significantly protecting cells and skin against free radical- or irradiation-induced enzymatic release and/or lipid peroxidation. Demonstrating a high activity at high dilutions where interactions of excipient become negligible, the new emulsions could be of great interest in sesamol-based pharmacology or topical applications. Drug Dev Res 69:251,266, 2008. © 2008 Wiley-Liss, Inc. [source] Electrospun Silk Fibroin Mats for Tissue EngineeringENGINEERING IN LIFE SCIENCES (ELECTRONIC), Issue 3 2008A. Alessandrino Abstract Processing Silk Fibroin (SF) with electrospinning (ES) offers a very attractive opportunity for producing a variety of 2D and 3D matrices with great potential for tissue regeneration and repair due to the superior biocompatibility and mechanical properties of SF. Different combinations of ES parameters were explored to investigate the best experimental set-up related to the dimension and uniformity of the fibers in the electrospun silk fibroin (ES-SF) mats. Using SEM it was found that the ES-SF mats contain uniform fibers with a diameter in the nanometric range obtained by electrospinning a 7.5,% w/v SF solution in formic acid, with an electric field of 2.4,kV/cm and a spinneret-collector distance of 10,cm. FT-IR and DSC analyses were performed to investigate the structure of the ES-SF mats before and after immersion in methanol for different times (5, 10, and 15,min). The methanol treatment was able to promote the crystallization of SF by conformational transition of random coil and other poorly ordered conformations (turns and bends) to the ,-sheet structure. The degree of crystallinity was enhanced as shown by the trend of both the FT-IR crystallinity index and the melting/decomposition peak temperature (from DSC). To study the cytocompatibility of ES-SF mats, tests with L929 murine fibroblasts were carried out. Samples were seeded with the cells and incubated for 1, 3, and 7,days at 37,°C. At each time point, SEM investigations and Alamar blue tests were performed. The SEM images showed cell adhesion and proliferation just after 1,day and cell confluence at 7,days. Alamar blue test demonstrated that there were very low differences between cell viability on ES-SF mats and the tissue culture plastic control. [source] FGF-2, IL-1, and TGF-, regulate fibroblast expression of S100A8FEBS JOURNAL, Issue 11 2005Farid Rahimi Growth factors, including fibroblast growth factor-2 (FGF-2) and transforming growth factor-, (TGF-,) regulate fibroblast function, differentiation and proliferation. S100A8 and S100A9 are members of the S100 family of Ca2+ -binding proteins and are now accepted as markers of inflammation. They are expressed by keratinocytes and inflammatory cells in human/murine wounds and by appropriately activated macrophages, endothelial cells, epithelial cells and keratinocytes in vitro. In this study, regulation and expression of S100A8 and S100A9 were examined in fibroblasts. Endotoxin (LPS), interferon , (IFN,), tumour-necrosis factor (TNF) and TGF-, did not induce the S100A8 gene in murine fibroblasts whereas FGF-2 induced mRNA maximally after 12 h. The FGF-2 response was strongly enhanced and prolonged by heparin. Interleukin-1, (IL-1,) alone, or in synergy with FGF-2/heparin strongly induced the gene in 3T3 fibroblasts. S100A9 mRNA was not induced under any condition. Induction of S100A8 in the absence of S100A9 was confirmed in primary fibroblasts. S100A8 mRNA induction by FGF-2 and IL-1, was partially dependent on the mitogen-activated-protein-kinase pathway and dependent on new protein synthesis. FGF-2-responsive elements were distinct from the IL-1,-responsive elements in the S100A8 gene promoter. FGF-2-/heparin-induced, but not IL-1,-induced responses were significantly suppressed by TGF-,, possibly mediated by decreased mRNA stability. S100A8 in activated fibroblasts was mainly intracytoplasmic. Rat dermal wounds contained numerous S100A8-positive fibroblast-like cells 2 and 4 days post injury; numbers declined by 7 days. Up-regulation of S100A8 by FGF-2/IL-1,, down-regulation by TGF-,, and its time-dependent expression in wound fibroblasts suggest a role in fibroblast differentiation at sites of inflammation and repair. [source] Direct-Write Assembly of 3D Hydrogel Scaffolds for Guided Cell GrowthADVANCED MATERIALS, Issue 23 2009Robert A. Barry III Planar and 3D hydrogel scaffolds are patterned via direct-write assembly of hydrogel-based inks. Through simultaneous ink writing and UV polymerization, both 1D and 3D microperiodic scaffolds are created. 3T3 murine fibroblasts are seeded onto the scaffolds and their process development is observed using fluorescence microscopy. [source] Decapeptide with fibroblast growth factor (FGF)-5 partial sequence inhibits hair growth suppressing activity of FGF-5JOURNAL OF CELLULAR PHYSIOLOGY, Issue 2 2003Chikako Ito Earlier studies demonstrated that knock-out of fibroblast growth factor-5 gene (Fgf-5) prolonged anagen VI phase of hair cycle, resulting long hairs in the mice. We showed the activities on hair growth of the two Fgf-5 gene products, one of which, FGF-5 suppressed hair growth by inhibiting anagen proceeding and inducing the transition from anagen to catagen, and FGF-5S, a shorter polypeptide with FGF-5-antagonizing activity translated from alternatively spliced mRNA, suppressed this activity of FGF-5. As the results suggested that FGF-5 antagonist would increase hair growth, we synthesized various peptides having partial sequences of human FGF-5 and FGF-5S and determined their FGF-5 antagonist activity. Among them, a decapeptide designated P3 (95-VGIGFHLQIY-104) that aligns with receptor binding sites of FGF-1 and FGF-2 suppressed FGF-5-induced proliferation of BALB/3T3 A31 and NIH/3T3 murine fibroblasts, and FGF receptor-1c (FGFR-1c)-transfected Ba/F3 cell line (FR-Ba/F3 cells). IC50s of this peptide on these cell proliferations were 64, 28, 146 ,M, respectively. On the other hand, IC50 of this peptide on binding of FGF-5 to the FGFR-1(IIIc)/Fc chimera was 483 ,M. Examination in dorsal depilated mice revealed that the P3 peptide reduced the activity of FGF-5 to recover hair pigmentation and hair follicle lengths. The classification of histologically observed skin sections showed FGF-5-induced delations of anagen procedure had reduced by the P3 peptide. The anti-Ki67 antibody staining of hair follicles was inhibited by administration of FGF-5, and this inhibition by FGF-5 was recovered by administration of the P3 peptide. The P3 peptide alone did not affect hair follicle length and hair cell proliferation. These results indicate that the decapeptide antagonized FGF-5 activity in vivo, and reduced the inhibition of FGF-5 in hair growth, confirming that FGF-5 inhibitors are promising substances against hair loss and/or for promoting hair growth. J. Cell. Physiol. 197: 272,283, 2003. © 2003 Wiley-Liss, Inc. [source] Overexpression of EIF3S3 promotes cancer cell growthTHE PROSTATE, Issue 11 2006Kimmo J. Savinainen Abstract BACKGROUND Amplification and overexpression of EIF3S3 gene has been demonstrated in breast and prostate cancer. Here, our goal was to study the effect of EIF3S3 on cell growth. METHODS The effect of EIF3S3 on growth of NIH 3T3 murine fibroblasts as well as breast (SK-Br-3 and ZR-75-1) and prostate (PC-3 and LNCaP) cancer cell lines was examined by using transfection with inducible pTet-Off system and siRNAs. RESULTS NIH 3T3 cells with overexpression of EIF3S3 grew significantly faster than cells transfected with empty vector and survived longer when grown in soft agar. The EIF3S3 overexpression was associated with increased fraction of cells in S-phase and with phosphorylation of retinoblastoma (Rb) protein. siRNA treatment inhibited significantly (P,=,0.0022) the growth of all breast and prostate cancer cell lines studied. CONCLUSIONS The results suggest that EIF3S3 regulates cell growth and viability, and that overexpression of the gene may provide growth advantage to the cancer cells. Prostate © 2006 Wiley-Liss, Inc. [source] Fluorescence spectroscopy of H-ras transfected murine fibroblasts: A comparison with Monte Carlo simulationsBIOPOLYMERS, Issue 2 2010Shlomo Mark Abstract Autofluorescence properties of tissues have been widely used to diagnose various types of malignancies. In this study, we measured the autofluorescence properties of H-ras transfected murine fibroblasts and the counterpart control cells. The pair of cells is genetically identical except for the transfected H-ras gene. We applied Monte Carlo simulations to evaluate the relative contributions of Rayleigh and Mie scattering effects towards fluorescence in an in vitro model system of normal and H-ras transfected fibroblasts. The experimental results showed that fluorescence emission intensity was higher for normal cells than the malignant counterpart cells by about 30%. In normal cells, linearity in emission intensity was observed for cell densities of up to 1.0 × 106 cells/ml whereas for transformed cells it was up to 1.4 × 106 cells/ml. Nuclear volume changes give good account for the differences in the intrinsic fluorescence between normal and malignant cells. The Monte Carlo (MC) code, newly developed for this study, explains both predominant experimental features: the large fluorescence intensity differences between the transfected and the corresponding control cells as well as the phenomena of the red shift in the excitation spectra as a function of cell density. The contribution of Rayleigh scattering was found to be predominant compared to Mie scattering. © 2009 Wiley Periodicals, Inc. Biopolymers 93: 132,140, 2010. This article was originally published online as an accepted preprint. The "Published Online" date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com [source] Retrovirus-Polymer Complexes: Study of the Factors Affecting the Dose Response of TransductionBIOTECHNOLOGY PROGRESS, Issue 2 2007Natalia Landázuri We have previously shown that complexes of Polybrene (PB), chondroitin sulfate C (CSC), and retrovirus transduce cells more efficiently than uncomplexed virus because the complexes are large and sediment, reaching the cells more rapidly than by diffusion. Transduction reaches a peak at equal weight concentrations of CSC and PB and declines when the dose of PB is higher or lower than CSC. We hypothesized that the nonlinear dose response of transduction was a complex function of the molecular characteristics of the polymers, cell viability, and the number of viruses incorporated into the complexes. To test this hypothesis, we formed complexes using an amphotropic retrovirus and several pairs of oppositely charged polymers and used them to transduce murine fibroblasts. We examined the effect of the type and concentration of polymers used on cell viability, the size and charge of the complexes, the number of viruses incorporated into the complexes, and virus binding and transduction. Transduction was enhanced (2.5- to 5.5-fold) regardless of which polymers were used and was maximized when the number of positive charge groups was in slight excess (15,28%) of the number of negative charge groups. Higher doses of cationic polymer were cytotoxic, whereas complexes formed with lower doses were smaller, contained fewer viruses, and sedimented more slowly. These results show that the dose response of transduction by virus-polymer complexes is nonlinear because excess cationic polymer is cytotoxic, whereas excess anionic polymer reduces the number of active viruses that are delivered to the cells. [source] | ||||||||||||||||