913 resultados para bone marrow mesenchymal stem cell
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Muscular dystrophy refers to a group of more than 30 genetical disorders characterized by progressive weakness and degeneration of the skeletal muscle. No effective therapy is available at present. Recent studies have reported that the transplantation of stem cells can offer an important potential therapy for genetic diseases. Adult bone marrow mesenchymal stem cells have been identified as a nonhematopoietic stem cell population capable of self-renewal with the ability to differentiate into many cell lineages, including bone, fat, cartilage and connective tissue. Because of their similarity with muscle progenitor cells, when they are injected in affected individuals, they are able to migrate into areas of skeletal muscle degeneration and participate in the regeneration process. The adipose tissue represents an alternative source of MSCs that, as the MSCs derived from bone marrow, are capable of in vitro differentiation into osteogenic, adipogenic, myogenic and chondrogenic lineages. The objective of this project is to investigate the “in vitro” myogenic potential of mesenchymal stem cells derived from murine bone marrow and adipose tissue. Four experimental groups were analyzed: mice from lineages Lama2dy-2J/J and C57black and, C2C12 lineage cells and transformed C2C12 expressing the eGFP protein. MSCs cultures were obtained by flushing the bone marrow femurs and tibials with α-MEM or by the subcutaneous and inguinal fat from the mice. Their characterization was done by flow cytometry and in vitro differentiation. Muscle differentiation was studied through the analysis of the expression of transcriptional factors involved in muscle differentiation and/or the presence and amount of specific proteins from muscle differentiated cell. The pluripotency from bone marrow MSCs of the two lineages was evidenced and, in the muscular differentiation... (Complete abstract click electronic access below)
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Over the past few years, in veterinary medicine there has been an increased interest in understanding the biology of mesenchymal stem cells (MSCs). This interest comes from their potential clinical use especially in wound repair, tissue engineering and application in therapeutics fields, including regenerative surgery. MSCs can be isolated directly from bone marrow aspirates, adipose tissue, umbilical cord and various foetal tissues. In this study, mesenchymal stem cells were isolated from equine bone marrow, adipose tissue, cord blood, Wharton’s Jelly and, for the first time, amniotic fluid. All these cell lines underwent in vitro differentiation in chondrocytes, osteocytes and adipocytes. After molecular characterization, cells resulted positive for mesenchymal markers such as CD90, CD105, CD44 and negative for CD45, CD14, CD34 and CD73. Adipose tissue and bone marrow mesenchymal stem cells were successfully applied in the treatment of tendinitis in race horses. Furthermore, for the first time in the horse, skin wounds of septicemic foal, were treated applying amniotic stem cells. Finally, results never reported have been obtained in the present study, isolating mesenchymal stem cells from domestic cat foetal fluid and membranes. All cell lines underwent in vitro differentiation and expressed mesenchymal molecular markers.
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Mesenchymal stem cell (MSC) therapy is a promising approach for regaining muscle function after trauma. Prior to clinical application, the ideal time of transplantation has to be determined. We investigated the effects of immediate and delayed transplantation. Sprague-Dawley rats received a crush trauma to the left soleus muscle. Treatment groups were transplanted locally with 2 × 10(6) autologous MSCs, either immediately or 7 days after trauma. Saline was used as sham therapy. Contraction force tests and histological analyses were performed 4 weeks after injury. GFP-labelled MSCs were followed after transplantation. The traumatized soleus muscles of the sham group displayed a reduction of twitch forces to 36 ± 17% and of tetanic forces to 29 ± 11% of the non-injured right control side, respectively. Delayed MSC transplantation resulted in a significant improvement of contraction maxima in both stimulation modes (twitch, p = 0.011; tetany, p = 0.014). Immediate transplantation showed a significant increase in twitch forces to 59 ± 17% (p = 0.043). There was no significant difference in contraction forces between muscles treated by immediate and delayed cell transplantation. We were able to identify MSCs in the interstitium of the injured muscles up to 4 weeks after transplantation. Despite the fundamental differences of the local environment, which MSCs encounter after transplantation, similar results could be obtained with respect to functional muscle regeneration. We believe that transplanted MSCs residing in the interstitial compartment evolve their regenerative capabilities through paracrine pathways. Our data suggest a large time window of the therapeutical measures.
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Hyperthermia and local drug delivery have been proposed the potential therapeutic approaches for bone defects resulting from malignant bone tumors. Development of bioactive materials with magnetic and drug-delivery properties may potentially meet this target. The aim of this study is to develop a multifunctional mesoporous bioactive glass (MBG) scaffold system for both hyperthermia and local-drug delivery application potentially. For this aim, Iron (Fe) containing MBG (Fe-MBG) scaffolds with hierarchically large pores (300-500 µm) and fingerprint-like mesopores (4.5 nm) have been successfully prepared. The effect of Fe on the mesopore structure, physiochemical, magnetism, drug delivery and biological properties of MBG scaffolds has been systematically investigated. The results showed that the morphology of the mesopore varied from straight channels to curved fingerprint-like channels after incorporated parts of Fe into MBG scaffolds. The magnetism magnitude of MBG scaffolds can be tailored by controlling Fe contents. Furthermore, the incorporating of Fe into mesoporous MBG glass scaffolds enhanced the mitochondrial activity and bone-relative gene (ALP and OCN) expression of human bone marrow mesenchymal stem cells (BMSCs) on the scaffolds. The obtained Fe-MBG scaffolds also possessed high specific surface areas and sustained drug delivery. Therefore, Fe-MBG scaffolds are magnetic, degradable and bioactive. The multifunction of Fe-MBG scaffolds indicates that there is a great potential for Fe-MBG scaffolds to be used for the therapy and regeneration of large-bone defects caused by malignant bone tumors through the combination of hyperthermia, local drug delivery and their osteoconductivity.
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Divalent cobalt ions (Co2+) have been shown to possess the capacity to induce angiogenesis by activating hypoxia inducible factor-1α (HIF-1α) and subsequently inducing the production of vascular endothelial growth factor (VEGF). However, there are few reports about Co-containing biomaterials for inducing in vitro angiogenesis. The aim of the present work was to prepare Co-containing β-tricalcium phosphate (Co-TCP) ceramics with different contents of calcium substituted by cobalt (0, 2, 5 mol%) and to investigate the effect of Co substitution on their physicochemical and biological properties. Co-TCP powders were synthesized by a chemistry precipitation method and Co-TCP ceramics were prepared by sintering the powder compacts. The effect of Co substitution on phase transition and the sintering property of the β-TCP ceramics was investigated. The proliferation and VEGF expression of human bone marrow mesenchymal stem cells (HBMSCs) cultured with both powder extracts and ceramic discs of Co-TCP was further evaluated. The in vitro angiogenesis was evaluated by the tube-like structure formation of human umbilical vein endothelial cells (HUVECs) cultured on ECMatrix™ in the presence of powder extracts. The results showed that Co substitution suppressed the phase transition from β- to α-TCP. Both the powder extracts and ceramic discs of Co-TCP had generally good cytocompatibility to support HBMSC growth. Importantly, the incorporation of Co into β-TCP greatly stimulated VEGF expression of HBMSCs and Co-TCP showed a significant enhancement of network structure formation of HUVECs compared with pure TCP. Our results suggested that the incorporation of Co into bioceramics is a potential viable way to enhance angiogenic properties of biomaterials. Co-TCP bioceramics may be used for bone tissue regeneration with improved angiogenic capacity.
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We and others have published on the rapid manufacture of micropellet tissues, typically formed from 100-500 cells each. The micropellet geometry enhances cellular biological properties, and in many cases the micropellets can subsequently be utilized as building blocks to assemble complex macrotissues. Generally, micropellets are formed from cells alone, however when replicating matrix-rich tissues such as cartilage it would be ideal if matrix or biomaterials supplements could be incorporated directly into the micropellet during the manufacturing process. Herein we describe a method to efficiently incorporate donor cartilage matrix into tissue engineered cartilage micropellets. We lyophilized bovine cartilage matrix, and then shattered it into microscopic pieces having average dimensions < 10 μm diameter; we termed this microscopic donor matrix "cartilage dust (CD)". Using a microwell platform, we show that ~0.83 μg CD can be rapidly and efficiently incorporated into single multicellular aggregates formed from 180 bone marrow mesenchymal stem/stromal cells (MSC) each. The microwell platform enabled the rapid manufacture of thousands of replica composite micropellets, with each micropellet having a material/CD core and a cellular surface. This micropellet organization enabled the rapid bulking up of the micropellet core matrix content, and left an adhesive cellular outer surface. This morphological organization enabled the ready assembly of the composite micropellets into macroscopic tissues. Generically, this is a versatile method that enables the rapid and uniform integration of biomaterials into multicellular micropellets that can then be used as tissue building blocks. In this study, the addition of CD resulted in an approximate 8-fold volume increase in the micropellets, with the donor matrix functioning to contribute to an increase in total cartilage matrix content. Composite micropellets were readily assembled into macroscopic cartilage tissues; the incorporation of CD enhanced tissue size and matrix content, but did not enhance chondrogenic gene expression.
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目的 利用微模式化基底研究基底几何微结构对骨髓间充质干细胞增殖、分化及迁移过程的影响.方法 设计制作微模式化基底,用以控制细胞的铺展形态和面积.比较不同模式控制下大鼠骨髓间充质干细胞的增殖、分化和迁移数据.结果 细胞铺展宽度狭小可抑制骨髓间充质干细胞的增殖,细胞铺展形状可以调节其向成骨细胞分化的进程,细胞铺展面积受限时迁移增强,其增殖迁移行为减弱与成骨细胞诱导因子地塞米松的作用有关.结论 细胞铺展的几何形状和面积是骨髓间充质干细胞增殖、分化及迁移过程中的重要调节因子.
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We hypothesise that following a bone fracture there is systemic recruitment of bone forming cells to a fracture site. A rabbit ulnar osteotomy model was adapted to trace the movement of osteogenic cells. Bone marrow mesenchymal stem cells from 41 NZW rabbits were isolated, culture-expanded and fluorescently labelled. The labelled cells were either re-implanted into the fracture gap (Group A); into a vein (Group B); or into a remote tibial bone marrow cavity 48 h after the osteotomy (Group C) or 4 weeks before the osteotomy was established (Group D), and a control group (Group E) had no labelled cells given. To quantify passive leakage of cells to an injury site, inert beads were also co-delivered in Group B. Samples of the fracture callus tissue and various organs were harvested at discrete sacrifice time-points to trace and quantify the labelled cells. At 3 weeks following osteotomy, the number of labelled cells identified in the callus of Group C, was significantly greater than following IV delivery, Group B, and there was no difference in the number of labelled cells in the callus tissues, between Groups C and A, indicating the labelled bone marrow cells were capable of migrating to the fracture sites from the remote bone marrow cavity. Significantly fewer inert beads than labelled cells were identified in Group B callus, suggesting some of the bone-forming cells were actively recruited and selectively chosen to the fracture site, rather than passively leaked into the circulation and to bone injury site. This investigation supports the hypothesis that some osteoblasts involved in fracture healing were systemically mobilised and recruited to the fracture from remote bone marrow sites. © 2005 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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BACKGROUND: Febrile neutropenia (FN) and other infectious complications are some of the most serious treatment-related toxicities of chemotherapy for cancer, with a mortality rate of 2% to 21%. The two main types of prophylactic regimens are granulocyte (G-CSF) or granulocyte-macrophage colony stimulating factors (GM-CSF); and antibiotics, frequently quinolones or cotrimoxazole. Important current guidelines recommend the use of colony stimulating factors when the risk of febrile neutropenia is above 20% but they do not mention the use of antibiotics. However, both regimens have been shown to reduce the incidence of infections. Since no systematic review has compared the two regimens, a systematic review was undertaken. OBJECTIVES: To compare the effectiveness of G-CSF or GM-CSF with antibiotics in cancer patients receiving myeloablative chemotherapy with respect to preventing fever, febrile neutropenia, infection, infection-related mortality, early mortality and improving quality of life. SEARCH STRATEGY: We searched The Cochrane Library, MEDLINE, EMBASE, databases of ongoing trials, and conference proceedings of the American Society of Clinical Oncology and the American Society of Hematology (1980 to 2007). We planned to include both full-text and abstract publications. SELECTION CRITERIA: Randomised controlled trials comparing prophylaxis with G-CSF or GM-CSF versus antibiotics in cancer patients of all ages receiving chemotherapy or bone marrow or stem cell transplantation were included for review. Both study arms had to receive identical chemotherapy regimes and other supportive care. DATA COLLECTION AND ANALYSIS: Trial eligibility and quality assessment, data extraction and analysis were done in duplicate. Authors were contacted to obtain missing data. MAIN RESULTS: We included two eligible randomised controlled trials with 195 patients. Due to differences in the outcomes reported, the trials could not be pooled for meta-analysis. Both trials showed non-significant results favouring antibiotics for the prevention of fever or hospitalisation for febrile neutropenia. AUTHORS' CONCLUSIONS: There is no evidence for or against antibiotics compared to G(M)-CSFs for the prevention of infections in cancer patients.
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Intensive therapy and autologous blood and marrow transplantation (ABMT) is an established post-remission treatment for acute myeloid leukemia (AML), although its exact role remains controversial and few data are available regarding longer-term outcomes. We examined the long-term outcome of patients with AML transplanted at a single center using uniform intensive therapy consisting of etoposide, melphalan and TBI. In all, 145 patients with AML underwent ABMT: 117 in first remission, 21 in second remission and seven beyond second remission. EFS and OS were significantly predicted by remission status (P
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Aim. To compare the incorporation, growth, and chondrogenic potential of bone marrow (BM) and adipose tissue (AT) mesenchymal stem cells (MSCs) in scaffolds used for cartilage repair. Methods. Human BM and AT MSCs were isolated, culture expanded, and characterised using standard protocols, then seeded into 2 different scaffolds, Chondro-Gide or Alpha Chondro Shield. Cell adhesion, incorporation, and viable cell growth were assessed microscopically and following calcein AM/ethidium homodimer (Live/Dead) staining. Cell-seeded scaffolds were treated with chondrogenic inducers for 28 days. Extracellular matrix deposition and soluble glycosaminoglycan (GAG) release into the culture medium was measured at day 28 by histology/immunohistochemistry and dimethylmethylene blue assay, respectively. Results. A greater number of viable MSCs from either source adhered and incorporated into Chondro-Gide than into Alpha Chondro Shield. In both cell scaffolds, this incorporation represented less than 2% of the cells that were seeded. There was a marked proliferation of BM MSCs, but not AT MSCs, in Chondro-Gide. MSCs from both sources underwent chondrogenic differentiation following induction. However, cartilaginous extracellular matrix deposition was most marked in Chondro- Gide seeded with BM MSCs. Soluble GAG secretion increased in chondrogenic versus control conditions. There was no marked difference in GAG secretion by MSCs from either cell source. Conclusion. Chondro-Gide and Alpha Chondro Shield were permissive to the incorporation and chondrogenic differentiation of human BM and AT MSCs. Chondro-Gide seeded with BM MSCs demonstrated the greatest increase in MSC number and deposition of a cartilaginous tissue.