| Bioheart Makes Breakthrough in Cardiovascular Therapy with Stem Cells Obtained from Fat Tissue
September 30, 2009 at 5:39 pm
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| Cardiac stem cell trial seeks to treat some heart attack patients
September 30, 2009 at 5:39 pm
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| Teen attitudes toward smoking linked to likelihood of drinking and using drugs
September 30, 2009 at 2:14 pm
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| Celebrate Darwin's bicentennial by exploring how Darwin 'defined' evolutionary biology
September 30, 2009 at 2:14 pm
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| $16.8 million grant awarded to develop platelet recovery treatments
September 30, 2009 at 12:12 pm
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| Osiris Therapeutics to Present at Fourth Annual JMP Securities Healthcare Focus Conference
September 30, 2009 at 10:12 am
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| Article Published in Expert Opinion on Biological Therapy Evaluates StemEx(R) (carlecortemcel-l) for Leukemia and Lymphoma
September 30, 2009 at 8:17 am
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| The potential of biophotonic techniques in stem cell tracking and monitoring of tissue regeneration applied to cardiac stem cell therapy.
September 30, 2009 at 6:59 am
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| | The potential of biophotonic techniques in stem cell tracking and monitoring of tissue regeneration applied to cardiac stem cell therapy. J Biophotonics. 2009 Sep 28; Authors: Wilson BC, Vitkin IA, Matthews DL The use of injected stem cells, leading to regeneration of ischemic heart tissue, for example, following coronary artery occlusion, has emerged as a major new option for managing 'heart attack' patients. While some clinical trials have been encouraging, there have also been failures and there is little understanding of the multiplicity of factors that lead to the outcome. In this overview paper, the opportunities and challenges in applying biophotonic techniques to regenerative medicine, exemplified by the challenge of stem cell therapy of ischemic heart disease, are considered. The focus is on optical imaging to track stem cell distribution and fate, and optical spectroscopies and/or imaging to monitor the structural remodeling of the tissue and the resulting functional changes. The scientific, technological, and logistics issues involved in moving some of these techniques from pre-clinical research mode ultimately into the clinic are also highlighted. ((c) 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim). PMID: 19787683 [PubMed - as supplied by publisher] |
| Cardiomyocyte Differentiation of Human Induced Pluripotent Stem Cells.
September 30, 2009 at 6:59 am
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| | Cardiomyocyte Differentiation of Human Induced Pluripotent Stem Cells. Circulation. 2009 Sep 28; Authors: Zwi L, Caspi O, Arbel G, Huber I, Gepstein A, Park IH, Gepstein L BACKGROUND: -The ability to derive human induced pluripotent stem (hiPS) cell lines by reprogramming of adult fibroblasts with a set of transcription factors offers unique opportunities for basic and translational cardiovascular research. In the present study, we aimed to characterize the cardiomyocyte differentiation potential of hiPS cells and to study the molecular, structural, and functional properties of the generated hiPS-derived cardiomyocytes. Methods and Results-Cardiomyocyte differentiation of the hiPS cells was induced with the embryoid body differentiation system. Gene expression studies demonstrated that the cardiomyocyte differentiation process of the hiPS cells was characterized by an initial increase in mesoderm and cardiomesoderm markers, followed by expression of cardiac-specific transcription factors and finally by cardiac-specific structural genes. Cells in the contracting embryoid bodies were stained positively for cardiac troponin-I, sarcomeric alpha-actinin, and connexin-43. Reverse-transcription polymerase chain reaction studies demonstrated the expression of cardiac-specific sarcomeric proteins and ion channels. Multielectrode array recordings established the development of a functional syncytium with stable pacemaker activity and action potential propagation. Positive and negative chronotropic responses were induced by application of isoproterenol and carbamylcholine, respectively. Administration of quinidine, E4031 (IKr blocker), and chromanol 293B (IKs blocker) significantly affected repolarization, as manifested by prolongation of the local field potential duration. Conclusions-hiPS cells can differentiate into myocytes with cardiac-specific molecular, structural, and functional properties. These results, coupled with the potential of this technology to generate patient-specific hiPS lines, hold great promise for the development of in vitro models of cardiac genetic disorders, for drug discovery and testing, and for the emerging field of cardiovascular regenerative medicine. PMID: 19786631 [PubMed - as supplied by publisher] |
| The collection and conservation in Italy of stem cells from umbilical cord blood.
September 30, 2009 at 6:59 am
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| | The collection and conservation in Italy of stem cells from umbilical cord blood. Med Law. 2009 Mar;28(2):387-400 Authors: Ricci G, Conti A, Paternoster M, Buccelli P The blood contained in the umbilical cord offers a precious source of pluripotent stem cells, easily obtainable without invasive procedures, a source that, unlike embryonic stem cells, affords greater respect for ethical concerns. In relation to the therapeutic potential of these stem cells, personalized blood banks for newborns have been created and in various countries systems of research and cryoconservation of umbilical cord blood have been created, especially in private facilities. This facilitates promotion of the culture of donation and development of a network of umbilical cord blood sources, and spurs research to evaluate the real therapeutic potential of these cells. Italy has long prohibited management of umbilical cord blood in private form. Today, with new laws, Italy has achieved the indispensable legislative update in acknowledgment of social needs. Actually, the achieved system is solid autologous conservation. It guarantees to conserve a greater number of umbilical cords in public and private facilities. PMID: 19705649 [PubMed - indexed for MEDLINE] |
| [Tissue engineering: a solution for organ replacement?]
September 30, 2009 at 6:59 am
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| | [Tissue engineering: a solution for organ replacement?] J Chir (Paris). 2009 Apr;146(2):109-11 Authors: Gaujoux S, Larghero J, Cattan P PMID: 19523633 [PubMed - indexed for MEDLINE] |
| The potential of biophotonic techniques in stem cell tracking and monitoring of tissue regeneration applied to cardiac stem cell therapy.
September 30, 2009 at 6:40 am
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| | The potential of biophotonic techniques in stem cell tracking and monitoring of tissue regeneration applied to cardiac stem cell therapy. J Biophotonics. 2009 Sep 28; Authors: Wilson BC, Vitkin IA, Matthews DL The use of injected stem cells, leading to regeneration of ischemic heart tissue, for example, following coronary artery occlusion, has emerged as a major new option for managing 'heart attack' patients. While some clinical trials have been encouraging, there have also been failures and there is little understanding of the multiplicity of factors that lead to the outcome. In this overview paper, the opportunities and challenges in applying biophotonic techniques to regenerative medicine, exemplified by the challenge of stem cell therapy of ischemic heart disease, are considered. The focus is on optical imaging to track stem cell distribution and fate, and optical spectroscopies and/or imaging to monitor the structural remodeling of the tissue and the resulting functional changes. The scientific, technological, and logistics issues involved in moving some of these techniques from pre-clinical research mode ultimately into the clinic are also highlighted. ((c) 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim). PMID: 19787683 [PubMed - as supplied by publisher] |
| Modeling of flow-induced shear stress applied on 3D cellular scaffolds; Implications for vascular tissue-engineering.
September 30, 2009 at 6:24 am
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| | Modeling of flow-induced shear stress applied on 3D cellular scaffolds; Implications for vascular tissue-engineering. Biotechnol Bioeng. 2009 Sep 28; Authors: Lesman A, Blinder Y, Levenberg S Novel tissue-culture bioreactors employ flow-induced shear-stress as a means of mechanical stimulation of cells. We developed a computational fluid dynamics model of the complex 3D microstructure of a porous scaffold incubated in a direct perfusion bioreactor. Our model was designed to predict high shear-stress values within the physiological range of those naturally sensed by vascular cells (1-10 dyne/cm(2)), and will thereby provide suitable conditions for vascular tissue-engineering experiments. The model also accounts for cellular growth, which was designed as an added cell layer grown on all scaffold walls. Five model variants were designed, with geometric differences corresponding to cell-layer thicknesses of 0, 50, 75, 100 and 125 microm. Four inlet velocities (0.5, 1, 1.5 and 2 cm/sec) were applied to each model. Wall shear-stress distribution and overall pressure drop calculations were then used to characterize the relation between flow rate, shear stress, cell-layer thickness and pressure drop. The simulations showed that cellular growth within 3D scaffolds exposes cells to elevated shear stress, with considerably increasing average values in correlation to cell growth and inflow velocity. Our results provide in-depth analysis of the microdynamic environment of cells cultured within 3D environments, and thus provide advanced control over tissue development in-vitro. (c) 2009 Wiley Periodicals, Inc. PMID: 19787638 [PubMed - as supplied by publisher] |
| Inverse engineering of medical devices made of bioresorbable polymers.
September 30, 2009 at 6:24 am
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| | Inverse engineering of medical devices made of bioresorbable polymers. Comput Methods Biomech Biomed Engin. 2009 Sep 21;:1 Authors: Huang R, Pan J The degradation of medical devices made of bioresorbable polymers such as fixation devices in orthopaedic surgeries and scaffolds for tissue engineering can take from months to years. The trial and error approach of device development is therefore problematic and mathematical modelling of the biodegradation can help to accelerate the device development. This paper presents an inverse scheme to obtain the material parameters in a biodegradation model developed by Pan and his co-workers from existing experimental data of bioresorbable devices. The parameters can then be used to predict the degradation rate of new devices made of the same polymer. Firstly, the previously developed model is briefly outlined. Secondly, a finite element scheme and a time integration algorithm are developed for the direct analysis using the biodegradation model. Thirdly, an inverse analysis scheme is presented in combination with the direct analysis. Finally, several case studies of existing degradation data are presented to demonstrate the effectiveness of the inverse engineering approach. PMID: 19787498 [PubMed - as supplied by publisher] |
| New methods to diagnose and treat cartilage degeneration.
September 30, 2009 at 6:24 am
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| | New methods to diagnose and treat cartilage degeneration. Nat Rev Rheumatol. 2009 Sep 29; Authors: Daher RJ, Chahine NO, Greenberg AS, Sgaglione NA, Grande DA Lesions in articular cartilage can result in significant musculoskeletal morbidity and display unique biomechanical characteristics that make repair difficult, at best. Several surgical procedures have been devised in an attempt to relieve pain, restore function, and delay or stop the progression of cartilaginous lesions. Advanced MRI and ultrasonography protocols are currently used in the evaluation of tissue repair and to improve diagnostic capability. Other nonoperative modalities, such as injection of intra-articular hyaluronic acid or supplementary oral glucosamine and chondroitin sulfate, have shown potential efficacy as anti-inflammatory and symptom-modifying agents. The emerging field of tissue engineering, involving the use of a biocompatible, structurally and mechanically stable scaffold, has shown promising early results in cartilage tissue repair. Scaffolds incorporating specific cell sources and bioactive molecules have been the focus in this new exciting field. Further work is required to better understand the behavior of chondrocytes and the variables that influence their ability to heal articular lesions. The future of cartilage repair will probably involve a combination of treatments in an attempt to achieve a regenerative tissue that is both biomechanically stable and, ideally, identical to the surrounding native tissues. PMID: 19786989 [PubMed - as supplied by publisher] |
| Knockdown of angiotensinogen by shRNA-mediated RNA interference inhibits human visceral preadipocytes differentiation.
September 30, 2009 at 6:24 am
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| | Knockdown of angiotensinogen by shRNA-mediated RNA interference inhibits human visceral preadipocytes differentiation. Int J Obes (Lond). 2009 Sep 29; Authors: Ye ZW, Wu XM, Jiang JG Objective:The immediate cause of obesity is the massive deposition of subcutaneous and visceral fat attributing to the continuous proliferation and differentiation of preadipocytes. The identification of the underlying molecular mechanisms of preadipocytes differentiation is urgent, and will have an important role in plastic and reconstructive surgical procedures.Methods:Two small hairpin RNA (shRNA)-mediated RNA interference plasmids have been constructed on the basis of the activity of H1 promoter-driven expression vector psiRNA-hH1neo to suppress the expression of angiotensinogen (AGT) in human preadipocytes-visceral (HPA-v). Subsequently, glycerol-3-phosphate dehydrogenase (G3PDH) activity and intracytoplasmic lipids content were detected during the process of HPA-v differentiation.Results:Small hairpin RNA-expressing vectors have been successfully constructed to suppress the expression of AGT significantly. Both intracytoplasmic lipids content and G3PDH activity decreased to a certain extent compared with that in the control group in the whole process of HPA-v differentiation.Conclusions:Two shRNA-mediated AGT-targeting plasmids inhibited the process of HPA-v differentiation to a certain extent. However, the accumulation of intracytoplasmic lipids was not exclusively determined by the expression of AGT, and it may also be regulated by other factors. In conclusion, this study provided a method to inhibit the process of preadipocytes differentiation, and it may have a role in obesity treatment and adipose tissue engineering application.International Journal of Obesity advance online publication, 29 September 2009; doi:10.1038/ijo.2009.197. PMID: 19786968 [PubMed - as supplied by publisher] |
| alpha-Fetoprotein as a modulator of the pro-inflammatory response of human keratinocytes.
September 30, 2009 at 6:24 am
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| | alpha-Fetoprotein as a modulator of the pro-inflammatory response of human keratinocytes. Br J Pharmacol. 2009 Sep 28; Authors: Potapovich AI, Pastore S, Kostyuk VA, Lulli D, Mariani V, De Luca C, Dudich EI, Korkina LG Background and purpose: The immunomodulatory effects of alpha-fetoprotein (AFP) on lymphocytes and macrophages have been described in vitro and in vivo. Recombinant forms of human AFP have been proposed as potential therapeutic entities for the treatment of autoimmune diseases. We examined the effects of embryonic and recombinant human AFP on the spontaneous, UVA- and cytokine-induced pro-inflammatory responses of human keratinocytes. Experimental approach: Cultures of primary and immortalized human keratinocytes (HaCaT) and human blood T lymphocytes were used. The effects of AFP on cytokine expression were studied by bioplexed elisa and quantitative reverse transcriptase polymerase chain reaction assay. Kinase and nuclear factor kappa B (NFkappaB) phosphorylation were quantified by intracellular elisa. Nuclear activator protein 1 and NFkappaB DNA binding activity was measured by specific assays. Nitric oxide and H(2)O(2) production and redox status were assessed by fluorescent probe and biochemical methods. Key results: All forms of AFP enhanced baseline expression of cytokines, chemokines and growth factors. AFP dose-dependently increased tumour necrosis factor alpha-stimulated granulocyte macrophage colony stimulating factor and interleukin 8 expression and decreased tumour necrosis factor alpha-induced monocyte chemotactic protein 1 and IP-10 (interferon gamma-produced protein of 10 kDa) expression. AFP induced a marked activator protein 1 activation in human keratinocytes. AFP also increased H(2)O(2) and modulated nitrite/nitrate levels in non-stimulated keratinocytes whereas it did not affect these parameters or cytokine release from UVA-stimulated cells. Phosphorylation of extracellular signal-regulated kinase (ERK1/2) and Akt1 but not NFkappaB was activated by AFP alone or by its combination with UVA. Conclusions and implications: Exogenous AFP induces activation of human keratinocytes, with de novo expression of a number of pro-inflammatory mediators and modulation of their pro-inflammatory response to cytokines or UVA. AFP may modulate inflammatory events in human skin. PMID: 19785658 [PubMed - as supplied by publisher] |
| Shining light on a new class of hydrogels.
September 30, 2009 at 6:24 am
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| | Shining light on a new class of hydrogels. Nat Biotechnol. 2009 Jun;27(6):543-4 Authors: Jay SM, Saltzman WM PMID: 19513057 [PubMed - indexed for MEDLINE] |
| Use of tissue-engineered skin to study in vitro biofilm development.
September 30, 2009 at 6:24 am
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| | Use of tissue-engineered skin to study in vitro biofilm development. Dermatol Surg. 2009 Sep;35(9):1334-41 Authors: Charles CA, Ricotti CA, Davis SC, Mertz PM, Kirsner RS BACKGROUND: Biofilms are aggregations of microorganisms that have been identified as potential pathogens in the chronicity of nonhealing wounds. OBJECTIVE To develop an in vitro wound model to study biofilms using Graftskin, a tissue-engineered skin equivalent. MATERIALS AND METHODS: Graftskin constructs were divided into sections, and wounds were created on each section. Bacterial suspensions with a concentration of 10(6) CFU/mL were prepared from cultures of pathogenic isolates of Pseudomonas aeruginosa and Staphylococcus aureus. A 25-microL aliquot of each suspension was deposited in the center of wounds created on the Graftskin. Sections were incubated at various time points, and a biopsy was then taken from the wounded and inoculated area. Sections were visualized with light (hematoxylin and eosin) and epifluorescent microscopy (calcofluor white and ethidium bromide). RESULTS Biofilm was observed on the wound model. Biofilm formation was dependent on time of Graftskin exposure to the bacteria. Biofilm was visualized in the S. aureus group at an earlier time point than in the P. aeruginosa group. CONCLUSIONS: We demonstrated biofilm formation in vitro using a wound model. This model may provide a basis on which future studies may explore therapeutic modalities to prevent and eradicate pathogenic bacterial biofilm. The authors have indicated no significant interest with commercial supporters. PMID: 19496791 [PubMed - indexed for MEDLINE] | 
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