|  |  |  | | | | | TE-RegenMed-StemCell feed | | | | | | | | | | | | | | | | | | | Fully biodegradable self-rolled polymer tubes: a candidate for tissue engineering scaffolds. Biomacromolecules. 2011 Apr 27; Authors: Zakharchenko S, Sperling E, Ionov L We report an approach for the fabrication of fully biodegradable self-rolled tubes based on patterned polysuccinimide/polycaprolactone bilayers. These polymers are biocompatible, biodegradable, produced industrially and are already approved for biomedical purposes. Both polycaprolactone and polysuccinimide are hydrophobic and intrinsically water insoluble. Polysuccinimide, however, is able to hydrolyze in physiological buffer environment yielding water-swellable polyaspartic acid that causes rolling of polymer bilayer and formation of tubes. We demonstrate the possibility to encapsulate yeast cells using self-rolled tubes. PMID: 21524116 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Rosiglitazone-induced adipogenesis in a bone marrow mesenchymal stem cell line - biomed 2011. Biomed Sci Instrum. 2011;47:213-21 Authors: Wang D, Haile A, Jones LC In vitro modeling of adipose tissue is essential for the study of adipogenesis and related diseases as well as for the development of surgical reconstruction procedures and tissue-engineering applications. Peroxisome proliferator activated receptor ? (PPAR?) has been shown to play an integral role in stimulating adipogenesis. There are several established ligands for PPAR?, including rosiglitazone. D1 cells, a multipotential cell line derived from mouse bone marrow, were treated with increasing (0.1, 1, 10, and 30 µM) concentrations of rosiglitazone in DMEM for 48 hours followed by treatment by DMEM alone for up to 15 days. All doses of rosiglitazone stimulated the accumulation of lipids ,which was notable by day 6. The adipogenic effect of rosiglitazone was maximized at doses of 10 and 30 µM. Adipogenesis for rosiglitazone-treated cells was greater than that for cells treated with dexamethasone, a conventional method used to stimulate adipogenesis. Significantly higher levels of triglyceride-G (TG) and mature adipocyte markers (PPAR-, adipocyte fatty acid-binding protein) were observed with rosiglitazone treatment after 6 days. Cytokines in the supernatants were analyzed by multiplex-based ELISA assays at day 6 after treatment; these cells release adiponectin, resistin, PAI-1, MCP-1, and VEGF with either rosiglitazone or dexamethasone treatment. However, rosiglitazone treatment had lower osteocalcin release than did the control. This study provides evidence that rosiglitazone treatment is a reliable method that can be used to induce adipogenesis of D1 cells, a pluripotential cell line from mouse bone marrow. PMID: 21525623 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | Solid-state cryomilling for porogen mixing and porous scaffold fabrication - biomed 2011. Biomed Sci Instrum. 2011;47:258-63 Authors: Allaf RM, Rivero IV Several widely used techniques for the fabrication of three dimensional (3D) scaffolds utilize the particulate leaching method to achieve a porous structure. This method involves the selective leaching of a mineral or an organic compound to generate pores. However, scaffolds prepared by this technique tend to exhibit limited interconnectivity. Therefore, to enhance the interconnectivity of the scaffolds fabricated by particulate leaching, a polymeric porogen can be added during processing. Typically porogens are mixed into a polymer solution, powder, or melt. The mixture is subsequently cast, molded, or extruded, and then leaching the porogens results in porous scaffolds. Still, even though scaffold interconnectivity is improved through the addition of polymer porogens, particulate leaching does not yield scaffolds with uniform properties. This research introduces a new solventless approach, cryomilling, to blend porogens and attain interconnected porous scaffolds with uniform morphologies. To validate the efficacy of the suggested approach a comparison of the effect of various solid-state mixing approaches on scaffold morphology and mechanical properties will be made. In this study, salt particles and poly(ethylene oxide) (PEO) were mixed (manually or through cryomilling) with poly(e-caprolactone) (PCL) for the preparation of porous 3D PCL scaffolds, the mixtures were then compression molded, and subsequently, water was used to leach the porogens. Morphological and compressive properties of the resulting scaffolds will be discussed. This simple, novel, economical, organic solvent-free approach for the fabrication of 3D interconnected porous scaffolds holds promise for tissue engineering applications. PMID: 21525630 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | Human bone marrow mesenchymal stem cells: a systematic reappraisal via the genostem experience. Stem Cell Rev. 2011 Mar;7(1):32-42 Authors: Charbord P, Livne E, Gross G, Häupl T, Neves NM, Marie P, Bianco P, Jorgensen C Genostem (acronym for "Adult mesenchymal stem cells engineering for connective tissue disorders. From the bench to the bed side") has been an European consortium of 30 teams working together on human bone marrow Mesenchymal Stem Cell (MSC) biological properties and repair capacity. Part of Genostem activity has been dedicated to the study of basic issues on undifferentiated MSCs properties and on signalling pathways leading to the differentiation into 3 of the connective tissue lineages, osteoblastic, chondrocytic and tenocytic. We have evidenced that native bone marrow MSCs and stromal cells, forming the niche of hematopoietic stem cells, were the same cellular entity located abluminally from marrow sinus endothelial cells. We have also shown that culture-amplified, clonogenic and highly-proliferative MSCs were bona fide stem cells, sharing with other stem cell types the major attributes of self-renewal and of multipotential priming to the lineages to which they can differentiate (osteoblasts, chondrocytes, adipocytes and vascular smooth muscle cells/pericytes). Extensive transcription profiling and in vitro and in vivo assays were applied to identify genes involved in differentiation. Thus we have described novel factors implicated in osteogenesis (FHL2, ITGA5, Fgf18), chondrogenesis (FOXO1A) and tenogenesis (Smad8). Another part of Genostem activity has been devoted to studies of the repair capacity of MSCs in animal models, a prerequisite for future clinical trials. We have developed novel scaffolds (chitosan, pharmacologically active microcarriers) useful for the repair of both bone and cartilage. Finally and most importantly, we have shown that locally implanted MSCs effectively repair bone, cartilage and tendon. PMID: 20198518 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | Fabrication of nano-structured electrospun collagen scaffold intended for nerve tissue engineering. J Mater Sci Mater Med. 2011 Apr 28; Authors: Timnak A, Yousefi Gharebaghi F, Pajoum Shariati R, Bahrami SH, Javadian S, Hojjati Emami S, Shokrgozar MA Nerve tissue engineering is one of the most promising methods in nerve tissue regeneration. The development of blended collagen and glycosaminoglycan scaffolds can potentially be used in many soft tissue engineering applications. In this study an attempt was made to develop two types of random and aligned electrospun, nanofibrous scaffold using collagen and a common type of glycosaminoglycan. Ion chromatography test, MTT and attachment assays were conducted respectively to trace the release of glycosaminoglycan, and to investigate the biocompatibility of the scaffold. Cell cultural tests showed that the scaffold acted as a positive factor to support connective tissue cell outgrowth. The positive effect of fiber orientation on cell outgrowth organization was traced through SEM images. Porosity percentage calculation and tensile strength measurement of the webs specified analogous properties to the native neural matrix tissue. These results suggested that nanostructured porous collagen-glycosaminoglycan scaffold is a potential cell carrier in nerve tissue engineering. PMID: 21526410 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Bio-electrospraying primary cardiac cells: in vitro tissue creation and functional study. Biotechnol J. 2011 Jan;6(1):86-95 Authors: Ng KE, Joly P, Jayasinghe SN, Vernay B, Knight R, Barry SP, McComick J, Latchman D, Stephanou A Manifestations of myocardial infarctions have been recognized as one of the major killers in the Western world. Therefore, advancing and developing novel cardiac tissue repair and replacement therapeutics have great implications to our health sciences and well-being. There are several approaches for forming cardiac tissues, non-jet-based and jet-based methodologies. A unique advantage of jet-based approaches is the possibility to handle living cells with a matrix for cell distribution and deposition in suspension, either as single or heterogeneous cell populations. Our previous studies on bio-electrospraying of cardiac cells have shown great promise. Here, we show for the first time the ability to bio-electrospray the three major cell types of the myocardium, both independently and simultaneously, for forming a fully functional cardiac tissue. Several samples are characterized in vitro and found to be indistinguishable in comparison to controls. Thus, we are describing a swiftly emerging novel biotechnique for direct cardiac tissue generation. Moreover, the present investigations pave the way for the development and optimization of a bio-patterning approach for the fabrication of biologically viable cardiac tissue grafts for the potential treatment of severe heart failure after myocardial infarction. PMID: 21053334 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | Bottom-up tissue engineering. Curr Opin Biotechnol. 2011 Apr 25; Authors: Elbert DL Recapitulating the elegant structures formed during development is an extreme synthetic and biological challenge. Great progress has been made in developing materials to support transplanted cells, yet the complexity of tissues is far beyond that found in even the most advanced scaffolds. Self-assembly is a motif used in development and a route for the production of complex materials. Self-assembly of peptides, proteins and other molecules at the nanoscale is promising, but in addition, intriguing ideas are emerging for self-assembly of micron-scale structures. In this brief review, very recent advances in the assembly of micron-scale cell aggregates and microgels will be described and discussed. PMID: 21524904 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Laser-assisted bioprinting for creating on-demand patterns of human osteoprogenitor cells and nano-hydroxyapatite. Biofabrication. 2011 Apr 28;3(2):025001 Authors: Catros S, Fricain JC, Guillotin B, Pippenger B, Bareille R, Remy M, Lebraud E, Desbat B, Amédée J, Guillemot F Developing tools to reproduce and manipulate the cell micro-environment, including the location and shape of cell patterns, is essential for tissue engineering. Parallel to inkjet printing and pressure-operated mechanical extruders, laser-assisted bioprinting (LAB) has emerged as an alternative technology to fabricate two- and three-dimensional tissue engineering products. The objective of this work was to determine laser printing parameters for patterning and assembling nano-hydroxyapatite (nHA) and human osteoprogenitors (HOPs) in two and three dimensions with LAB. The LAB workstation used in this study comprised an infrared laser focused on a quartz ribbon that was coated with a thin absorbing layer of titanium and a layer of bioink. The scanning system, quartz ribbon and substrate were piloted by dedicated software, allowing the sequential printing of different biological materials into two and/or three dimensions. nHA printing material (bioink) was synthesized by chemical precipitation and was characterized prior and following printing using transmission electron microscopy, Fourier transformed infrared spectroscopy and x-ray diffraction. HOP bioink was prepared using a 30 million cells ml(-1) suspension in culture medium and cells were characterized after printing using a Live/Dead assay and osteoblastic phenotype markers (alcaline phosphatase and osteocalcin). The results revealed that LAB allows printing and organizing nHA and HOPs in two and three dimensions. LAB did not alter the physico-chemical properties of nHA, nor the viability, proliferation and phenotype of HOPs over time (up to 15 days). This study has demonstrated that LAB is a relevant method for patterning nHA and osteoblastic cells in 2D, and is also adapted to the bio-fabrication of 3D composite materials. PMID: 21527813 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Cotransplantation of autologous bone marrow stromal cells and chondrocytes as a novel therapy for reconstruction of condylar cartilage. Med Hypotheses. 2011 Apr 25; Authors: Dai J, Wang X, Shen G Condylar cartilage is absolutely necessary for the normal function of temporomandibular joint (TMJ). Unfortunately, condylar cartilage defect or missing is also one of the common clinical problems. Repair or reconstruction of cartilage is always a hot topic. Cell based cartilage regeneration is suggested as novel therapies in cartilage tissue engineering, and autologous chondrocytes were initially regarded as the ideal cell source. However, there are some disadvantages such as its limited augmentation capability for culture in vitro and may differentiate to other types of cells. On the other hand, bone marrow stromal cells (BMSCs) have gained special interest in tissue engineering. Because they can be obtained easily, cause relatively minor trauma and show the potential of long-run ex vivo expansion capacity. What most important is their capacity of multi-directional differentiation. They can differentiate into a variety of other types of cells when there are supplement exogenous factors or genes, but their clinical use is limited by safety concerns such as toxicity, insertional teratogenic, uncontrollable gene expression. Fortunately, the chondrocytes microenvironment has been demonstrated that could induce BMSCs to structure cartilage when culture in vitro or reimplanted in nude mice subcutaneously area. So in this article, we hypothesize that cotransplantation of autologous BMSCs and chondrocytes, which coculture with extracellular scaffolds, is a novel therapy for reconstruction of TMJ condylar cartilage. In our strategy, advantages of two types of cells are utilized and shortcomings are avoided, which strongly improve the feasibility and clinical safety, finally bring great hope to the patients with TMJ disease. PMID: 21524860 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Distinct stem cells subpopulations isolated from human adipose tissue exhibit different chondrogenic and osteogenic differentiation potential. Stem Cell Rev. 2011 Mar;7(1):64-76 Authors: Rada T, Reis RL, Gomes ME Recently adipose tissue has become a research topic also for the searching for an alternative stem cells source to use in cell based therapies such as tissue engineer. In fact Adipose Stem Cells (ASCs) exhibit an important differentiation potential for several cell lineages such as chondrogenic, osteogenic, myogenic, adipogenic and endothelial cells. ASCs populations isolated using standard methodologies (i.e., based on their adherence ability) are very heterogeneous but very few studies have analysed this aspect. Consequently, several questions are still pending, as for example, on what regard the existence/ or not of distinct ASCs subpopulations. The present study is originally aimed at isolating selected ASCs subpopulations, and to analyse their behaviour towards the heterogeneous population regarding the expression of stem cell markers and also regarding their osteogenic and chondrogenic differentiation potential. Human Adipose derived Stem Cells (hASCs) subpopulations were isolated using immunomagnetic beads coated with several different antibodies (CD29, CD44, CD49d, CD73, CD90, CD 105, Stro-1 and p75) and were characterized by Real Time RT-PCR in order to assess the expression of mesenchymal stem cells markers (CD44, CD73, Stro-1, CD105 and CD90) as well as known markers of the chondrogenic (Sox 9, Collagen II) and osteogenic lineage (Osteopontin, Osteocalcin). The obtained results underline the complexity of the ASCs population demonstrating that it is composed of several subpopulations, which express different levels of ASCs markers and exhibit distinctive differentiation potentials. Furthermore, the results obtained clearly evidence of the advantages of using selected populations in cell-based therapies, such as bone and cartilage regenerative medicine approaches. PMID: 20396979 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | Designs from the deep: Marine organisms for bone tissue engineering. Biotechnol Adv. 2011 Apr 17; Authors: Clarke SA, Walsh P, Maggs CA, Buchanan F Current strategies for bone repair have accepted limitations and the search for synthetic graft materials or for scaffolds that will support ex vivo bone tissue engineering continues. Biomimetic strategies have led to the investigation of naturally occurring porous structures as templates for bone growth. The marine environment is rich in mineralizing organisms with porous structures, some of which are currently being used as bone graft materials and others that are in early stages of development. This review describes the current evidence available for these organisms, considers the relative promise of each and suggests potential future directions. PMID: 21527337 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Cellular and paracellular transplants for spinal cord injury: a review of the literature. Childs Nerv Syst. 2011 Feb;27(2):237-43 Authors: Mortazavi MM, Verma K, Tubbs RS, Theodore N Experimental approaches to limit the spinal cord injury and to promote neurite outgrowth and improved function from a spinal cord injury have exploded in recent decades. Due to the cavitation resulting after a spinal cord injury, newer important treatment strategies have consisted of implanting scaffolds with or without cellular transplants. There are various scaffolds, as well as various different cellular transplants including stem cells at different levels of differentiation, Schwann cells and peripheral nerve implants, that have been reviewed. Also, attention has been given to different re-implantation techniques in avulsion injuries. PMID: 20972681 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | Preparation of decellularized and crosslinked artery patch for vascular tissue-engineering application. J Mater Sci Mater Med. 2011 Apr 28; Authors: Zhao Y, Zhang Z, Wang J, Yin P, Wang Y, Yin Z, Zhou J, Xu G, Liu Y, Deng Z, Zhen M, Cui W, Liu Z There is an urgent clinical need of tissue-engineering (TE) vascular grafts, so this study was for developing a fast and simple way of producing TE vascular scaffold. The TE vascular scaffold was prepared with pepsin, DNase and RNase enzymatic decellularization and crosslinked with 0.1, 1, 5% glutaraldehyde (GA), respectively. The samples were underwent analyses of burst pressure; suture strength; cytotoxicity; enzymatic degradation in vitro; degradation in vivo; rehydration; biocompatibilities detected with hematoxylin and eosin (H&E), scan electron microscope, immunohistochemistry both in vivo and in vitro; macrophage infiltration and calcification using Von Kossa staining. After being decellularized the scaffold had a complete removal of cellular components, an intact collagen structure. The burst pressure and suture strength were similar to native artery. 0.1% GA crosslinked scaffold showed less cytotoxicity than 1 and 5% GA groups (P < 0.05) and was resistance to enzymatic degradation in vitro. Once being implanted, 0.1% GA group was resistant to degradation and formed endothelium, smooth muscle and adventitia with few macrophages infiltration. However, there appeared calcification in implants compared with that in native artery. This study demonstrated that DVPs producing methods by enzymatic decellularizing and crosslinking with 0.1% GA could be used for clinical TE vascular graft manufacture. PMID: 21528356 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | [Patterning different cells based on microfluidics and self-assembled monolayers]. Sheng Wu Gong Cheng Xue Bao. 2009 Aug;25(8):1234-9 Authors: Wu J, Shao J, Zheng Y, Jin Q, Zhao J The ability to pattern multiple cells through precise surface engineering of cell culture substrates has promoted the development of cellular bioassays, such as differentiation, interaction and molecular signaling pathways. There are several well developed ways to pattern cells. This report describes a method for patterning multiple types of cells based on microfluidics and self-assembled monolayers. We developed two types of micro-dam structures by soft-lithography to locate cells precisely and modified the substrate by a kind of self-assembled monolayer with property of electrochemical desorption to confine cells in specific areas. Finally we could pattern an array of two different types of cells closely and precisely. Cells were confined in specific areas but still shared the same microenvironment, so they could interact through soluble molecules. The substrate was transparent and open, so we could easily apply several instruments for research. With these merits, this cell chip is appropriate for investigating the interaction between different types of cells. PMID: 19938462 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | [Preparation and properties of novel human-like collagen-silk fibroin scaffold for blood vessel]. Sheng Wu Gong Cheng Xue Bao. 2009 Aug;25(8):1225-33 Authors: Zhu C, Fan D, Ma X, Xue W, Hui J, Chen L, Duan Z, Ma P In order to improve tensile property of vascular scaffold, we blended silk fibroin with novel human-like collagen with the mass ratio of 9:1, 7:3 and 5:5 (W/W), and then fabricated blood vessel tubular graft by freeze-drying process. We studied microstructure, mechanical properties, elements composites, degradability and biocompatibility of vascular scaffolds. These results showed that tubular scaffold with mass ratio 7:3 exhibited interconnected porous structure with pore size at (60 +/- 5) microm and porosity of 85%; achieved the desirable mechanical property (strain of 50% +/- 5% and stress of 332 +/- 16 kPa); had relatively slow degradation rate; could enhance cell adhesion and proliferation and had superior biocompatibility. PMID: 19938461 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | High-throughput combinatorial cell co-culture using microfluidics. Integr Biol (Camb). 2011 Apr 28; Authors: Tumarkin E, Tzadu L, Csaszar E, Seo M, Zhang H, Lee A, Peerani R, Purpura K, Zandstra PW, Kumacheva E Co-culture strategies are foundational in cell biology. These systems, which serve as mimics of in vivo tissue niches, are typically poorly defined in terms of cell ratios, local cues and supportive cell-cell interactions. In the stem cell niche, the ability to screen cell-cell interactions and identify local supportive microenvironments has a broad range of applications in transplantation, tissue engineering and wound healing. We present a microfluidic platform for the high-throughput generation of hydrogel microbeads for cell co-culture. Encapsulation of different cell populations in microgels was achieved by introducing in a microfluidic device two streams of distinct cell suspensions, emulsifying the mixed suspension, and gelling the precursor droplets. The cellular composition in the microgels was controlled by varying the volumetric flow rates of the corresponding streams. We demonstrate one of the applications of the microfluidic method by co-encapsulating factor-dependent and responsive blood progenitor cell lines (MBA2 and M07e cells, respectively) at varying ratios, and show that in-bead paracrine secretion can modulate the viability of the factor dependent cells. Furthermore, we show the application of the method as a tool to screen the impact of specific growth factors on a primary human heterogeneous cell population. Co-encapsulation of IL-3 secreting MBA2 cells with umbilical cord blood cells revealed differential sub-population responsiveness to paracrine signals (CD14+ cells were particularly responsive to locally delivered IL-3). This microfluidic co-culture platform should enable high throughput screening of cell co-culture conditions, leading to new strategies to manipulate cell fate. PMID: 21526262 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Coupling of gelatin to inner surfaces of pore walls in spongy alginate-based scaffolds facilitates the adhesion, growth and differentiation of human bone marrow mesenchymal stromal cells. J Mater Sci Mater Med. 2011 Apr 28; Authors: Petrenko YA, Ivanov RV, Petrenko AY, Lozinsky VI We have developed a novel wide-pore scaffold for cell 3D culturing, based on the technology of freeze-drying of Ca-alginate and gelatin. Two different preparation methodologies were compared: (i) freeze-drying of Na-alginate + gelatin mixed solution followed by the incubation of dried polymer in saturated ethanolic solution of CaCl(2); (ii) freeze-drying of the Na-alginate solution followed by the chemical "activation" of polysaccharide core with divinylsulfone with subsequent gelatin covalent attachment to the inner surfaces of pore walls. The scaffolds produced using the first approach did not provide adhesion and proliferation of human bone marrow mesenchymal stromal cells (MSCs). Conversely, the second approach allowed to obtain scaffolds with a high adherence ability for the cells. When cultured within the latter type of scaffold, MSCs proliferated and were able to differentiate into adipogenic, osteogenic and chondrogenic cell lineages, in response to specific induction stimuli. The results indicate that Ca-alginate wide-pore scaffolds with covalently attached gelatin could be useful for stem cell-based bone, cartilage and adipose tissue engineering. PMID: 21526407 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Inhibition of cellular senescence by developmentally regulated FGF-receptors in mesenchymal stem cells. Blood. 2011 Apr 28; Authors: Coutu DL, François M, Galipeau J Bone-derived mesenchymal stem cells (MSCs) are important cells for use in cell therapy, tissue engineering and regenerative medicine but also to study bone development, homeostasis and repair. However, little is known about their developmental ontology and in vivo identity. Because FGFs play key roles in bone development and their receptors are developmentally regulated in bones, we here hypothesized that MSCs should express FGF-receptors reflecting their developmental origin and potential. We show that FGFR1 and 2 are expressed by rare mesenchymal progenitors in putative MSC niches in vivo including perichondrium, periosteum and trabecular marrow. FGFR1+ cells often appeared as pericytes. These cells display a characteristic MSC phenotype in vitro when expanded with FGF-2, which appears to maintain MSC stemness by inhibiting cellular senescence through a PI3K/AKT-MDM2 pathway and promoting proliferation. FGFRs may thus be involved in MSCs self-renewal. In summary, FGFR1/2 are developmentally-regulated markers of MSCs in vivo and in vitro and are important to maintain MSCs stemness. PMID: 21527526 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Regenerative endodontics: A state of the art. Indian J Dent Res. 2011 Jan-Feb;22(1):122-31 Authors: Bansal R, Bansal R Scientific advances in the creation of restorative biomaterials, in vitro cell culture technology, tissue grafting, tissue engineering, molecular biology and the human genome project provide the basis for the introduction of new technologies into dentistry. Non-vital infected teeth have long been treated with root canal therapy (for mature root apex) and apexification (for immature root apex), or doomed to extraction. Although successful, current treatments fail to re-establish healthy pulp tissue in these teeth. But, what if the non-vital tooth could be made vital once again? That is the hope offered by regenerative endodontics, an emerging field focused on replacing traumatized and diseased pulp with functional pulp tissue. Restoration of vitality of non-vital tooth is based on tissue engineering and revascularization procedures. The purpose of this article is to review these biological procedures and the hurdles that must be overcome to develop regenerative endodontic procedures. PMID: 21525690 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | Plasticity of human menstrual blood stem cells derived from the endometrium. J Zhejiang Univ Sci B. 2011 May;12(5):372-380 Authors: Lin J, Xiang D, Zhang JL, Allickson J, Xiang C Stem cells can be obtained from women's menstrual blood derived from the endometrium. The cells display stem cell markers such as Oct-4, SSEA-4, Nanog, and c-kit (CD117), and have the potent ability to differentiate into various cell types, including the heart, nerve, bone, cartilage, and fat. There has been no evidence of teratoma, ectopic formation, or any immune response after transplantation into an animal model. These cells quickly regenerate after menstruation and secrete many growth factors to display recurrent angiogenesis. The plasticity and safety of the acquired cells have been demonstrated in many studies. Menstrual blood-derived stem cells (MenSCs) provide an alternative source of adult stem cells for research and application in regenerative medicine. Here we summarize the multipotent properties and the plasticities of MenSCs and other endometrial stem cells from recent studies conducted both in vitro and in vivo. PMID: 21528491 [PubMed - as supplied by publisher] | | | | | | | | | |  | |  | |  |
