|  |  |  | | | | | TERMSC | | | | | | | | | | | | | | | | | | | Current developments in the tissue engineering of autologous heart valves: moving towards clinical use. Future Cardiol. 2011 Jan;7(1):77-97 Authors: Apte SS, Paul A, Prakash S, Shum-Tim D The use of tissue-engineering methods to create autologous heart valve constructs has the potential to overcome the fundamental drawbacks of more traditional valve prostheses. Traditional mechanical valves, while durable, increase the risk for endocarditis and thrombogenesis, and require the recipient to continue lifelong anticoagulant therapy. Homograft or xenograft heart valve prostheses are associated with immune reaction and progressive deterioration with limited durability. Most importantly, neither option is capable of growth and remodeling in vivo and both options place the patient at risk for valve-related complications and reoperation. These shortcomings have prompted the application of tissue-engineering techniques to create fully autologous heart valve replacements. Future clinically efficacious tissue-engineered autologous valves should be nonthrombogenic, biocompatible, capable of growth and remodeling in vivo, implantable with current surgical techniques, hemodynamically perfect, durable for the patient's life and most importantly, significantly improve quality of life for the patient. In order to meet these expectations, the nature of the ideal biochemical milieu for conditioning an autologous heart valve will need to be elucidated. In addition, standardized criteria by which to quantitatively evaluate a tissue-engineered heart valve, as well as noninvasive analytical techniques for use in long-term animal models, will be required. This article highlights the advances, challenges and future clinical prospects in the field of tissue engineering of autologous heart valves, focusing on progress made by studies that have investigated a fully autologous, tissue-engineered pulmonary valve replacement in vivo. PMID: 21174513 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | [Concomitant cellular reactions in optic nerve siderosis existing for 30 years.] Ophthalmologe. 2010 Dec 22; Authors: Prokosch V, Spieker T, Merte RL, Thanos S Metal foreign bodies located in the optic nerve are a rare clinical picture and sooner or later often associated with vision loss. We report on a patient who had a foreign body in the optic nerve for 30 years. Histochemical analysis of the optic nerve after the requisite enucleation with complete functional loss of the eye revealed amazing results. Even 30 years after entry of the foreign body into the optic nerve neuronal structures with organized axons surrounded by cytoblasts, glial cells, and immunocompetent cells still remoined. These findings hold out hope and may serve as the starting point for regenerative medicine to potentially restore neuronal function. PMID: 21174099 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Identification of inducible brown adipocyte progenitors residing in skeletal muscle and white fat. Proc Natl Acad Sci U S A. 2010 Dec 20; Authors: Schulz TJ, Huang TL, Tran TT, Zhang H, Townsend KL, Shadrach JL, Cerletti M, McDougall LE, Giorgadze N, Tchkonia T, Schrier D, Falb D, Kirkland JL, Wagers AJ, Tseng YH Brown fat is specialized for energy expenditure and has therefore been proposed to function as a defense against obesity. Despite recent advances in delineating the transcriptional regulation of brown adipocyte differentiation, cellular lineage specification and developmental cues specifying brown-fat cell fate remain poorly understood. In this study, we identify and isolate a subpopulation of adipogenic progenitors (Sca-1(+)/CD45(-)/Mac1(-); referred to as Sca-1(+) progenitor cells, ScaPCs) residing in murine brown fat, white fat, and skeletal muscle. ScaPCs derived from different tissues possess unique molecular expression signatures and adipogenic capacities. Importantly, although the ScaPCs from interscapular brown adipose tissue (BAT) are constitutively committed brown-fat progenitors, Sca-1(+) cells from skeletal muscle and subcutaneous white fat are highly inducible to differentiate into brown-like adipocytes upon stimulation with bone morphogenetic protein 7 (BMP7). Consistent with these findings, human preadipocytes isolated from subcutaneous white fat also exhibit the greatest inducible capacity to become brown adipocytes compared with cells isolated from mesenteric or omental white fat. When muscle-resident ScaPCs are re-engrafted into skeletal muscle of syngeneic mice, BMP7-treated ScaPCs efficiently develop into adipose tissue with brown fat-specific characteristics. Importantly, ScaPCs from obesity-resistant mice exhibit markedly higher thermogenic capacity compared with cells isolated from obesity-prone mice. These data establish the molecular characteristics of tissue-resident adipose progenitors and demonstrate a dynamic interplay between these progenitors and inductive signals that act in concert to specify brown adipocyte development. PMID: 21173238 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Induced pluripotent stem cell-derived human platelets: one step closer to the clinic. J Exp Med. 2010 Dec 20;207(13):2781-4 Authors: Gekas C, Graf T The era of induced pluripotent stem (iPS) cells carries with it the promise of virtually unlimited sources of autologous cells for regenerative medicine. However, efficiently differentiating iPS cells into fully functional mature cell types remains challenging. A new study reporting the formation of fully functional platelets from human iPS (hiPS) cells improves upon recent efforts to generate this enucleated cell type, which remains in high demand for therapeutic transfusions. Notably, their lack of nucleus renders platelets unable to retain the pluripotent or tumorigenic properties of iPS cells. PMID: 21173109 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | The extent of irreversible myocardial damage and the potential for left ventricular repair after primary percutaneous coronary intervention. Am Heart J. 2010 Dec;160(6 Suppl):S4-S10 Authors: Esposito G, Dellegrottaglie S, Chiariello M Primary percutaneous coronary intervention (PCI) is currently recognized as a highly effective therapy for acute myocardial infarction (AMI) and has been shown to decrease myocardial damage and improve prognosis. Several diagnostic tools have been proposed to evaluate the myocardium at risk, the occurrence of no-reflow, the final scar size, and the presence of residual viable myocardium in patients treated by primary PCI. A large body of literature documents the relevant impact of each of these variables on outcomes in patients treated for AMI. In patients undergoing primary PCI, a number of treatment approaches have been proposed recently to improve efficacy by increasing myocardial salvage. This article describes the principal diagnostic tools (ie, serum biochemical markers, electrocardiography, echocardiography, nuclear imaging techniques, magnetic resonance imaging, and multidetector computed tomography) applicable for evaluation of the size and severity of myocardial damage in patients with AMI undergoing primary PCI. Proposed therapeutic strategies to repair irreversible myocardial damage in patients treated with primary PCI are also considered, with particular focus on the value of stem cell therapy in this specific setting. PMID: 21147291 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | Perivascular adipose tissue-derived complement 3 is required for adventitial fibroblast functions and adventitial remodeling in deoxycorticosterone acetate-salt hypertensive rats. Arterioscler Thromb Vasc Biol. 2010 Dec;30(12):2568-74 Authors: Ruan CC, Zhu DL, Chen QZ, Chen J, Guo SJ, Li XD, Gao PJ To examine the role of perivascular adipose tissue (PVAT)-derived factors in the regulation of adventitial fibroblast (AF) function in vitro and in vivo. PMID: 20864665 [PubMed - indexed for MEDLINE] | | | | | | | | | |  | |  | |  |
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