| A Selective Cytopheretic Inhibitory Device to Treat the Immunological Dysregulation of Acute and Chronic Renal Failure.
January 23, 2010 at 8:52 AM
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| | A Selective Cytopheretic Inhibitory Device to Treat the Immunological Dysregulation of Acute and Chronic Renal Failure. Blood Purif. 2010;29(2):183-190 Authors: Humes HD, Sobota JT, Ding F, Song JH Background: The poor outcomes in patients with acute kidney injury (AKI) and end-stage renal disease (ESRD) on chronic dialysis are due to immune dysregulation associated with these disorders. Evolving evidence suggests that the kidney, and specifically renal epithelial cells, plays an important role in the immunological response of leukocytes under disease states. Method: In this regard, the development of two therapeutic approaches utilizing renal epithelial cells and 'smart' immunomodulatory membranes has been tested in preclinical animal models and clinical trials. Results: These two approaches have been demonstrated in phase II human trials to improve the survival of intensive care unit patients with AKI and multiorgan failure. The use of a 'smart' immunomodulatory membrane is also being evaluated in a small exploratory clinical trial to assess its effects on immunoregulation in ESRD patients requiring chronic hemodialysis. Conclusions: The use of renal proge! nitor/stem cell therapy and/or cytopheretic membranes may result in effective treatments to alter the dysregulated immunological state of acute or chronic renal failure and improve the outcomes of these diseases. PMID: 20093825 [PubMed - as supplied by publisher] | | |
| Mesenchymal Stem Cell Therapy for Treatment of Cardiovascular Disease: Helping people sooner or later.
January 23, 2010 at 8:52 AM
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| | Mesenchymal Stem Cell Therapy for Treatment of Cardiovascular Disease: Helping people sooner or later. Stem Cells Dev. 2010 Jan 21; Authors: Trivedi PS, Tray NJ, Nguyen TD, Nigam N, Gallicano GI Despite advances in clinical management, cardiovascular disease remains the leading cause of death in America. While cardiomyocytes retain limited plasticity following maturation, the heart is grossly unable to recover from structural damage. Mesenchymal stem cell (MSC) therapy, through its promise of repair and regeneration of cardiac tissue, represents an exciting avenue of treatment for a range of cardiovascular diseases. MSCs are relatively immunopriviledged, lacking both major histocompatibility II and T cell co-stimulatory signal expression, and possess the unique ability to home into sites of myocardial damage when delivered systemically. Additionally they have been shown to provide therapeutic benefit via several distinct mechanisms, the most important of which appears to be the abundant secretion of paracrine factors that promote local regeneration. In light of this, several groups have sought to precondition MSCs, using various molecular and genetic mean! s, in order to enhance viability and growth factor secretion in the heart, following transplantation. Here we analyze and integrate information from recent MSC studies, focusing on underlying mechanisms of MSC-associated repair in animal models of cardiac disease. Additionally, MSC pretreatment studies are organized here to examine their relative effectiveness and potential for clinical use. Data emerging from ongoing human clinical trials are also evaluated for consistency with animal studies and their therapeutic promise. Finally, we attempt to answer whether cumulative evidence from animal and human studies is suggestive of significant, clinically viable cardiac repair in acute and chronic conditions and explore ways in which future studies can enhance effectiveness of cell-based therapy. PMID: 20092388 [PubMed - as supplied by publisher] | | |
| How to Successfully Incorporate Antiaging and Wellness into Your Practice: Things You Should Know.
January 23, 2010 at 6:40 AM
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| | How to Successfully Incorporate Antiaging and Wellness into Your Practice: Things You Should Know. Facial Plast Surg. 2010 Feb;26(1):12-15 Authors: Pontius AT, Smith PW Antiaging medicine is the fastest growing medical specialty. It would behoove plastic surgeons to give serious consideration to extending their practices to incorporate antiaging medicine given the similarities in their patient populations, office settings, and fee-for-service practices. It is important to find a practitioner board-certified in antiaging and regenerative medicine that has done a 2-year fellowship in the specialty. Additionally, you must structure your business relationship appropriate to your needs and your practice. There are several options for the arrangement, including (1) having the antiaging physician use your office on your operative days or days off, (2) incorporating the antiaging physician as a part of your practice on a full-time or part-time basis, or (3) renting office space for the antiaging practice in your medi-spa, wellness center, or medical building. These are just some of the more common arrangements all with the ultimate goal ! of delineating your practice from others in your area, being a forerunner in the future of cutting-edge medical care and offering your patients the full array of aesthetic and health services. PMID: 20094964 [PubMed - as supplied by publisher] | | |
| New lines of GFP transgenic rats relevant for regenerative medicine and gene therapy.
January 23, 2010 at 6:40 AM
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| | New lines of GFP transgenic rats relevant for regenerative medicine and gene therapy. Transgenic Res. 2010 Jan 22; Authors: Remy S, Tesson L, Usal C, Menoret S, Bonnamain V, Nerriere-Daguin V, Rossignol J, Boyer C, Nguyen TH, Naveilhan P, Lescaudron L, Anegon I Adoptive cell transfer studies in regenerative research and identification of genetically modified cells after gene therapy in vivo require unequivocally identifying and tracking the donor cells in the host tissues, ideally over several days or for up to several months. The use of reporter genes allows identifying the transferred cells but unfortunately most are immunogenic to wild-type hosts and thus trigger rejection in few days. The availability of transgenic animals from the same strain that would express either high levels of the transgene to identify the cells or low levels but that would be tolerant to the transgene would allow performing long-term analysis of labelled cells. Herein, using lentiviral vectors we develop two new lines of GFP-expressing transgenic rats displaying different levels and patterns of GFP-expression. The "high-expresser" line (GFP(high)) displayed high expression in most tissues, including adult neurons and neural precursors, mesenc! hymal stem cells and in all leukocytes subtypes analysed, including myeloid and plasmacytoid dendritic cells, cells that have not or only poorly characterized in previous GFP-transgenic rats. These GFP(high)-transgenic rats could be useful for transplantation and immunological studies using GFP-positive cells/tissue. The "low-expresser" line expressed very low levels of GFP only in the liver and in less than 5% of lymphoid cells. We demonstrate these animals did not develop detectable humoral and cellular immune responses against both transferred GFP-positive splenocytes and lentivirus-mediated GFP gene transfer. Thus, these GFP-transgenic rats represent useful tools for regenerative medicine and gene therapy. PMID: 20094912 [PubMed - as supplied by publisher] | | |
| Improving regenerating potential of the heart after myocardial infarction: Factor-based approach.
January 23, 2010 at 6:40 AM
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| | Improving regenerating potential of the heart after myocardial infarction: Factor-based approach. Life Sci. 2010 Jan 18; Authors: Hwang H, Kloner RA The emerging evidence that the heart has the potential to regenerate, albeit not ideally, has stimulated considerable interest in the field of cardiac regenerative medicine. Several lines of research demonstrated that factor-based therapy is feasible and effective, whether it is used independently or as an adjunct to cell therapy. The ultimate goal of the factor-based approach is to improve regenerating potential of the heart as a means to treat patients with cardiovascular disease. This article reviews recent approaches involving factor-based therapy for cardiac repair and regeneration including some of the advantages of this type of therapy as well as some of the hurdles that must be overcome before this therapeutic approach becomes a standard part of clinical medicine. PMID: 20093126 [PubMed - as supplied by publisher] | | |
| Engineering Tumors: A Tissue Engineering Perspective in Cancer Biology.
January 23, 2010 at 6:40 AM
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| | Engineering Tumors: A Tissue Engineering Perspective in Cancer Biology. Tissue Eng Part B Rev. 2010 Jan 21; Authors: Burdett E, Kasper FK, Mikos AG, Ludwig JA There is increasing recognition that 3-dimensional (3D) tissue culture technologies have many uses within the biomedical sciences beyond the scope of regenerative medicine. One such use is in the field of cancer biology, where a 3D tumor model that accurately recreates the in vivo tumor phenotype would be a valuable tool for studying tumor biology and would allow better preclinical evaluation of anticancer drug candidates. The most widely used model involves small cellular aggregates, termed spheroids, which have been used by cancer biologists for decades and have consistently shown the superiority of 3D tissue culture over standard 2D monolayer culture for mimicking the tumor behavior and drug resistance encountered in vivo. Currently, several research groups have begun to adapt more advanced 3D culture techniques from the tissue engineering field to create a more clinically accurate ex vivo model of tumor biology. PMID: 20092396 [PubMed - as supplied by publisher] | | |
| Neural potential of a stem cell population in the adipose and cutaneous tissues.
January 23, 2010 at 6:29 AM
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| | Neural potential of a stem cell population in the adipose and cutaneous tissues. Neurol Res. 2010 Feb;32(1):47-54 Authors: Zavan B, Michelotto L, Lancerotto L, Della Puppa A, D'Avella D, Abatangelo G, Vindigni V, Cortivo R OBJECTIVE: A significant amount of recent interest has been focused on the possibility that adult human stem cells are a realistic therapeutic alternative to embryonic stem cells. Multipotent stem cells that have characteristics reminiscent of embryonic neural crest stem cells have been isolated from several postnatal tissues, including skin, gut, dental pulp and the heart, and are potentially useful for research and therapeutic purposes. However, their neurogenic potential, including their ability to produce electrophysiologically active neurons, is largely unexplored. In the present work, we investigated this issue with regard to skin-derived precursors (SKPs) and adipose-derived stem cells (ADSc) Methods: Adult stem cells isolated from skin and from adipose tissue derived from the same adult donor were treated with epidermal growth factor (EGF) and fibroblast growth factor 2 (FGF2). Neurospheres obtained were first expanded and evaluated in term of proliferativ! e ability, and then their neuronal differentiation potential was analysed. RESULTS: Adipose- and skin-derived neurospheres grew in suspension as spheres in the presence of the mitogens FGF2 and EGF. With this protocols, the spheres have been able to proliferate and to originate Schwann and glial-like cells. DISCUSSION: In summary, we have demonstrated in this work that multipotent adult precursor cell can be isolated and expanded from two accessible adult tissue sources: skin and adipose tissue. The work described in this paper provides the framework for our attempts to use SKPs or ADSc as autologous adult stem cell population for cell replacement and discovery research. PMID: 20092695 [PubMed - in process] | | |
| In vitro cytocompatibility evaluation of a thermoresponsive NIPAAm-MMA copolymeric surface using L929 cells.
January 23, 2010 at 6:27 AM
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| | In vitro cytocompatibility evaluation of a thermoresponsive NIPAAm-MMA copolymeric surface using L929 cells. J Mater Sci Mater Med. 2010 Jan 22; Authors: Varghese VM, Raj V, Sreenivasan K, Kumary TV Scaffold free tissue constructs are preferred in tissue engineering as they overcome all the problems associated with scaffolds. Stimuli responsive polymers enable generation of scaffold free multilayered tissue constructs which would in turn reduce the use of biomaterials in vivo. In this study, we investigated cytocompatibility and thermoresponsiveness of a copolymer of N-Isopropylacrylamide and Methyl Methacrylate. Thermoresponsive surfaces were prepared by coating tissue culture polystyrene with the copolymer solution in isopropanol. Mammalian fibroblast cells (L929 cells) readily adhered on the copolymer. The viability and cellular activity was ensured through Neutral red staining, MTT assay, Tritiated thymidine uptake assay and Immunofluorescent staining for cytoskeletal organisation. Incubation under lower critical solution temperature of copolymer resulted in intact detachment of cells. To conclude, in-house synthesized cytocompatible smart culture substra! te intended for tissue engineering was developed using a cost effective and simple technique. Moreover, presence of methyl methacrylate in the copolymer reduced the lower critical solution temperature facilitating extended in vitro manipulation time. As the copolymer is insoluble in water, the copolymer could be polymerised without additional crosslinkers. PMID: 20094902 [PubMed - as supplied by publisher] | | |
| Emerging applications of stimuli-responsive polymer materials.
January 23, 2010 at 6:27 AM
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| | Emerging applications of stimuli-responsive polymer materials. Nat Mater. 2010 Feb;9(2):101-13 Authors: Stuart MA, Huck WT, Genzer J, Müller M, Ober C, Stamm M, Sukhorukov GB, Szleifer I, Tsukruk VV, Urban M, Winnik F, Zauscher S, Luzinov I, Minko S Responsive polymer materials can adapt to surrounding environments, regulate transport of ions and molecules, change wettability and adhesion of different species on external stimuli, or convert chemical and biochemical signals into optical, electrical, thermal and mechanical signals, and vice versa. These materials are playing an increasingly important part in a diverse range of applications, such as drug delivery, diagnostics, tissue engineering and 'smart' optical systems, as well as biosensors, microelectromechanical systems, coatings and textiles. We review recent advances and challenges in the developments towards applications of stimuli-responsive polymeric materials that are self-assembled from nanostructured building blocks. We also provide a critical outline of emerging developments. PMID: 20094081 [PubMed - in process] | | |
| Aging Fibroblasts Resist Phenotypic Maturation Because of Impaired Hyaluronan-Dependent CD44/Epidermal Growth Factor Receptor Signaling.
January 23, 2010 at 6:27 AM
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| | Aging Fibroblasts Resist Phenotypic Maturation Because of Impaired Hyaluronan-Dependent CD44/Epidermal Growth Factor Receptor Signaling. Am J Pathol. 2010 Jan 21; Authors: Simpson RM, Wells A, Thomas D, Stephens P, Steadman R, Phillips A Fibroblast differentiation into myofibroblasts is a key event during normal wound repair. We have previously demonstrated an age-related defect in this process associated with impaired synthesis of hyaluronan (HA) synthase (HAS) 2 but failed to prescribe its role in a mechanistic sense. Here we demonstrate that in addition to HAS2, there is loss of EGF receptor (EGF-R) in aged cells, and both are required for normal fibroblast functionality. Analysis of molecular events revealed that in young cells, transforming growth factor (TGF)-beta1-dependent phenotypic activation uses two distinct but cooperating pathways that involve TGF-beta receptor/Smad2 activation and EGF-mediated EGF-R/extracellular signal-regulated kinase (ERK) 1/2 signaling, and the latter is compromised with in vitro aging. Pharmacological inhibition of any of the five intermediates (TGF-beta receptor, Smad2, EGF, EGF-R, and ERK1/2) attenuated TGF-beta1 induction of alpha-smooth muscle actin. We pre! sent evidence that the HA receptor CD44 co-immunoprecipitates with EGF-R after activation by TGF-beta1. This interaction is HA-dependent because disruption of HA synthesis abrogates this association and inhibits subsequent ERK1/2 signaling. In aged fibroblasts, this association is lost with resultant suppression of ERK1/2 activation. Forced overexpression of EGF-R and HAS2 in aged cells restored TGF-beta1-mediated HA-CD44/EGF-R association and alpha-smooth muscle actin induction. Taken together, these results demonstrate that HA can serve as a signal integrator by facilitating TGF-beta1-mediated CD44-EGF-R-ERK interactions and ultimately fibroblast phenotype. We propose a model to explain this novel mechanism and the functional consequence of age-dependent. PMID: 20093489 [PubMed - as supplied by publisher] | | |
| In Vivo Evaluation of 3-Dimensional Polycaprolactone Scaffolds for Cartilage Repair in Rabbits.
January 23, 2010 at 6:27 AM
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| | In Vivo Evaluation of 3-Dimensional Polycaprolactone Scaffolds for Cartilage Repair in Rabbits. Am J Sports Med. 2010 Jan 21; Authors: Martinez-Diaz S, Garcia-Giralt N, Lebourg M, Gómez-Tejedor JA, Vila G, Caceres E, Benito P, Monleón Pradas M, Nogues X, Gómez Ribelles JL, Monllau JC Background Cartilage tissue engineering using synthetic scaffolds allows maintaining mechanical integrity and withstanding stress loads in the body, as well as providing a temporary substrate to which transplanted cells can adhere. Purpose This study evaluates the use of polycaprolactone (PCL) scaffolds for the regeneration of articular cartilage in a rabbit model. Study Design Controlled laboratory study. Methods Five conditions were tested to attempt cartilage repair. To compare spontaneous healing (from subchondral plate bleeding) and healing due to tissue engineering, the experiment considered the use of osteochondral defects (to allow blood flow into the defect site) alone or filled with bare PCL scaffold and the use of PCL-chondrocytes constructs in chondral defects. For the latter condition, 1 series of PCL scaffolds was seeded in vitro with rabbit chondrocytes for 7 days and the cell/scaffold constructs were transplanted into rabbits' articular defects, av! oiding compromising the subchondral bone. Cell pellets and bare scaffolds were implanted as controls in a chondral defect. Results After 3 months with PCL scaffolds or cells/PCL constructs, defects were filled with white cartilaginous tissue; integration into the surrounding native cartilage was much better than control (cell pellet). The engineered constructs showed histologically good integration to the subchondral bone and surrounding cartilage with accumulation of extracellular matrix including type II collagen and glycosaminoglycan. The elastic modulus measured in the zone of the defect with the PCL/cells constructs was very similar to that of native cartilage, while that of the pellet-repaired cartilage was much smaller than native cartilage. Conclusion The results are quite promising with respect to the use of PCL scaffolds as aids for the regeneration of articular cartilage using tissue engineering techniques. PMID: 20093424 [PubMed - as supplied by publisher] | | |
| Tibial Cartilage Damage and Deformation at Peak Displacement Compression During Simulated Landing Impact.
January 23, 2010 at 6:27 AM
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| | Tibial Cartilage Damage and Deformation at Peak Displacement Compression During Simulated Landing Impact. Am J Sports Med. 2010 Jan 21; Authors: Yeow CH, Ng YH, Lee PV, Goh JC Background Structural changes of articular cartilage at the point of peak displacement compression during a landing impact are unknown. Hypothesis Extent of damage and deformation is significantly different for superficial, middle, and deep cartilage zones at peak displacement compression during simulated landing impact compared with after impact. Study Design Controlled laboratory study. Methods Explants were extracted from porcine tibial cartilages and divided into 3 test conditions: nonimpact control, impact and release, and impact and hold. Impact compression, with peak deformation of 2 mm, was applied based on a single 10-Hz haversine to simulate landing impact. For impact and release, explants were subjected to formalin fixation on removal of load after impact. For impact and hold, explants were immediately immersed in formalin with peak deformation maintained at 2 mm. After fixation, the explants underwent histology, whereby Mankin scores and cartilage thic! knesses were obtained. Results Peak stresses of 9.8 to 28.1 MPa were noted during impact compression. For impact and release, substantial cartilage defects such as surface fraying and fissures were observed. For impact and hold, explants exhibited less severe matrix damage, such as superficial irregularities and tidemark disruption. Mankin scores were lower (indicating less damage; P < .05) in impact and hold than in impact and release condition. Superficial cartilage zone thickness was reduced (P < .05) in both impact and hold and impact and release conditions, relative to nonimpact control. Conclusion Not only does the loading phase of impact compression play a role in introducing substantial damage and deformation to cartilage, the unloading phase contributes to overall cartilage damage by exacerbating fissure propagation from surface lesions. Clinical Relevance Imaging of clinical injuries may underestimate the magnitude of cartilage compression that occurred duri! ng injury. Cartilage tissue engineering scaffolds must be desi! gned to cope with the effects of loading and unloading phases, especially at the superficial zone, so that the repair site can function as well as does the neighboring native cartilage. PMID: 20093423 [PubMed - as supplied by publisher] | | |
| Polymeric Composites containing Carbon Nanotubes for Bone Tissue Engineering.
January 23, 2010 at 6:27 AM
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| | Polymeric Composites containing Carbon Nanotubes for Bone Tissue Engineering. Int J Biol Macromol. 2010 Jan 18; Authors: Sahithi K, Swetha M, Ramasamy K, Srinivasan N, Selvamurugan N Several natural and synthetic polymers are now available for bone tissue engineering applications but they may lack mechanical integrity. In recent years, there are reports emphasizing the importance of carbon nanotubes (CNTs) in supporting bone growth. CNTs possess exceptional mechanical, thermal, and electrical properties, facilitating their use as reinforcements or additives in various materials to improve the properties of the materials. Biomaterials containing polymers often are placed adjacent to bone. The use of CNTs is anticipated in these biomaterials applied to bone mainly to improve their overall mechanical properties and expected to act as scaffolds to promote and guide bone tissue regeneration. This review paper provides a current state of knowledge available examining the use of the polymeric composites containing CNTs for promoting bone growth. PMID: 20093139 [PubMed - as supplied by publisher] | | |
| The biocompatibility of Pluronic((R))F127 fibrinogen-based hydrogels.
January 23, 2010 at 6:27 AM
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| | The biocompatibility of Pluronic((R))F127 fibrinogen-based hydrogels. Biomaterials. 2010 Jan 19; Authors: Shachaf Y, Gonen-Wadmany M, Seliktar D Our research is focused on the design of hydrogel biomaterials that can be used for 3-D cell encapsulation and tissue engineering. In this study, our goal was to engineer a temperature-responsive biomaterial to possess bioactive properties using polymer and protein chemistry, and at the same time provide the biomaterial with susceptibility to cell-mediated remodeling. Toward this goal, we developed a biomimetic material that can harness the bioactive properties of fibrinogen and the unique structural properties of Pluronic((R))F127. Pluronic((R))F127 is a synthetic block copolymer that exhibits reverse thermal gelation (RTG) in response to small changes in ambient temperature. We conjugated fibrinogen to Pluronic((R))F127 to create a biosynthetic precursor with tunable physicochemical properties based on the relationship between the two constituents. A hydrogel matrix was formed from the fibrinogen-F127 adducts by free-radical polymerization using light activation! (photo-polymerization). These materials displayed a reversible temperature-induced physical sol-gel transition and an irreversible light-activated chemical cross-linking. The susceptibility of this hydrogel biomaterial to protease degradation and consequent cell-mediated remodeling was controlled by the Pluronic((R))F127 constituent. The protein-based material also conveyed inductive signals to cells through bioactive sites on the fibrinogen backbone, as well as through structural properties such as the matrix modulus. We apply these materials as a tissue engineering hydrogel scaffold for 3-D in vitro culture of dermal fibroblasts in order to gain a better understanding of how the material bioactivity and matrix properties can independently affect cell morphology and remodeling. PMID: 20092890 [PubMed - as supplied by publisher] | | |
| [Tissue engineering of vascular graft from decellularized arterial matrix and mesenchymal stem cells.]
January 23, 2010 at 6:27 AM
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| | [Tissue engineering of vascular graft from decellularized arterial matrix and mesenchymal stem cells.] Zhonghua Wai Ke Za Zhi. 2009 Oct 1;47(19):1491-4 Authors: Dong JD, Zhang J, Gu YQ, Li CM, Wang CR, Chen B, Li JX, Wu YF, Zhang SW, Meng Y, Wang ZG OBJECTIVE: To investigate the method of constructing small-diameter vascular grafts from xenogenic decellularized arterial matrices and mesenchymal stem cells (MSCs). METHODS: Porcine iliac arteries were decellularized by detergent and trypsin treatment. Histology, mechanical strength and porosity experiments were performed to evaluate the properties of decellularized matrices. MSCs were isolated from bone marrow of dogs and expanded ex vivo. Decellularized matrices were seeded with MSCs and further cultured in a pulsatile bioreactor. Morphological features of the tissue engineered grafts were assayed by HE staining and scanning electron microscopy. RESULTS: After cell extraction, absence of cellular components and preservation of extracellular matrix were verified. Mechanical strength of decellularized matrices was slightly reduced compared with native arteries. Porosity of decellularized matrices was 94.9%. Decellularized matrices were successfully seeded with M! SCs, which grew to a near-confluent monolayer under flow conditions and MSCs were highly elongated and oriented to the flow direction. CONCLUSION: Small-diameter vascular grafts can be constructed by seeding MSCs onto xenogenic decellularized arterial matrices and culturing in a pulsatile bioreactor. PMID: 20092764 [PubMed - in process] | | |
| Polyoctanediol citrate/sebacate bioelastomer films: surface morphology, chemistry and functionality.
January 23, 2010 at 6:27 AM
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| | Polyoctanediol citrate/sebacate bioelastomer films: surface morphology, chemistry and functionality. J Biomater Sci Polym Ed. 2010;21(2):237-51 Authors: Djordjevic I, Choudhury NR, Dutta NK, Kumar S, Szili EJ, Steele DA Elastomeric polyesters synthesized from non-toxic and biocompatible reactants are topical research materials for tissue-engineering applications. In such applications, the morphology, chemistry and functionality of the materials surfaces play a key role. While a number of papers have focused and reported on the fabrication and biological evaluation of elastic polyesters, only a few have attempted to characterise the surfaces of such materials. In this paper, we report on the preparation and surface characterization of films of a co-polyester bioelastomer, polyoctanediol citrate/sebacate (p(OCS)). The co-polymer was synthesized following the standard procedure of polyesterification using three non-toxic monomers (1,8-octanediol, citric acid and sebacic acid) in a catalyst-free environment. Nuclear magnetic resonance spectroscopy was used to monitor the chemical composition of the various p(OCS) elastomers. The p(OCS) films, prepared by both spin-coating and solvent! casting of the p(OCS) pre-polymer solutions, were characterized by scanning electron microscopy, UV-Vis titration, photo-acoustic Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy, and tested for their cytocompatibility. The results obtained suggest that the surface morphology, chemistry and the concentration of the surface functional groups can be controlled by simply varying the initial acid concentration (citric/sebacic acids) in the pre-polymer. The films supported the attachment and proliferation of osteoblast-like cells (MG63). This unique approach provides an effective method of controlling and monitoring the fundamental p(OCS) surface properties important for their potential utilisation as a tissue-engineering material. PMID: 20092687 [PubMed - in process] | | |
| Engineering Tumors: A Tissue Engineering Perspective in Cancer Biology.
January 23, 2010 at 6:27 AM
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| | Engineering Tumors: A Tissue Engineering Perspective in Cancer Biology. Tissue Eng Part B Rev. 2010 Jan 21; Authors: Burdett E, Kasper FK, Mikos AG, Ludwig JA There is increasing recognition that 3-dimensional (3D) tissue culture technologies have many uses within the biomedical sciences beyond the scope of regenerative medicine. One such use is in the field of cancer biology, where a 3D tumor model that accurately recreates the in vivo tumor phenotype would be a valuable tool for studying tumor biology and would allow better preclinical evaluation of anticancer drug candidates. The most widely used model involves small cellular aggregates, termed spheroids, which have been used by cancer biologists for decades and have consistently shown the superiority of 3D tissue culture over standard 2D monolayer culture for mimicking the tumor behavior and drug resistance encountered in vivo. Currently, several research groups have begun to adapt more advanced 3D culture techniques from the tissue engineering field to create a more clinically accurate ex vivo model of tumor biology. PMID: 20092396 [PubMed - as supplied by publisher] | | |
| Human amniotic fluid stem cells culture onto titanium screws: a new perspective for bone engineering.
January 23, 2010 at 6:27 AM
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| | Human amniotic fluid stem cells culture onto titanium screws: a new perspective for bone engineering. J Biol Regul Homeost Agents. 2009 Oct-Dec;23(4):277-9 Authors: Antonucci I, Pantalone A, De Amicis D, D'Onofrio S, Stuppia L, Palka G, Salini V The use of titanium plates and screws for osteosynthesis is considered to be an effective treatment for different kinds of fractures in orthopedic surgery. The aim of the present study is to test the ability of titanium screws to promote the growth of osteoblasts obtained from human amniotic fluid stem cells (AFS). Osteoblastic differentiation was assessed by RT-PCR of specific markers such as COL1, ONC, OPN, OCN, OPG, BMP-4 and Runx2. Mineralization was demonstrated by the presence of red depositions. Adherent cells were found to cover the whole surface of titanium screw by Scanning Electron Microscopy (SEM). The result indicates the excellent growth of osteoblasts obtained from amniotic fluid on a titanium surface and could represent an important point in view of a possible therapeutic application of AFS cells. PMID: 20003768 [PubMed - indexed for MEDLINE] | | | |
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