|  |  |  | | | | | TE-RegenMed-StemCell feed | | | | | | | | | | | | | | | | | | Two California state entities involved with the state's $3 billion stem cell agency examined its progress last week, ranging from its biotech loan program to election of a new chair.
The bodies are the Little Hoover Commission, the state's good government agency, and the Citizens Financial Accountability Oversight Committee(CFAOC), the only state body specifically charged with the overseeing | | | | | | | | | | | | | | | | | | | | | | | | | Idiopathic and secondary osteonecrosis of the femoral head show different thrombophilic changes and normal or higher levels of platelet growth factors. Acta Orthop. 2011 Feb 1; Authors: Cenni E, Fotia C, Rustemi E, Yuasa K, Caltavuturo G, Giunti A, Baldini N Background and purpose Thrombophilia represents a risk factor both for idiopathic and secondary osteonecrosis (ON). We evaluated whether clotting changes in idiopathic ON were different from corticosteroid-associated ON. As platelet-rich plasma has been proposed as an adjuvant in surgery, we also assessed whether platelet and serum growth factors were similar to those in healthy subjects. Methods 18 patients with idiopathic ON and 18 with corticosteroid-associated ON were compared with 44 controls for acquired and inherited thrombophilia. Platelet factor 4 (PF4), transforming growth factor-β1, platelet-derived growth factor-BB (PDGF-BB), and vascular endothelial growth factor were assayed in the supernatants of thrombin-activated platelets, in platelet lysates, and in serum from 14 ON patients and 10 controls. Results Idiopathic ON patients had higher plasminogen levels (median 118%) than controls (101%) (p = 0.02). Those with corticosteroid-associated ON had significantly higher D-dimer (333 ng/mL) and lower protein C levels (129%) than controls (164 ng/mL, p = 0.004; 160%, p = 0.02). The frequency of inherited thrombophilia was not different from the controls. No statistically significant differences were found between idiopathic and corticosteroid-associated ON. 20 of the 36 ON patients were smokers. (The controls were selected from smokers because nicotine favors hypercoagulability). ON patients had significantly higher serum PF4 levels (7,383 IU/mL) and PDGF-BB levels (3.1 ng/mL) than controls (4,697 IU/mL, p = 0.005; 2.2 ng/mL, p = 0.02). Interpretation Acquired hypercoagulability was common in both ON types, but the specific changes varied. The release of GF from platelets was not affected, providing a biological basis for platelet-rich plasma being used as an adjuvant in surgical treatment. PMID: 21281264 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Co-culture systems for vascularization- learning from Nature. Adv Drug Deliv Rev. 2011 Jan 28; Authors: Kirkpatrick CJ, Fuchs S, Unger RE The endothelial cell (EC) is practically ubiquitous in the human body and forms the inner cellular lining of the entire cardiovascular system. Following tissue injury, the microcirculation becomes the stage for both the inflammatory response and the subsequent healing reaction to restore physiological function to the damaged tissue. The advent of the multidisciplinary field of Regenerative Medicine (RegMed), of which Tissue Engineering (TE) and drug delivery using modern stimuli-responsive or interactive biomaterials are important components, has opened up new approaches to the acceleration of the healing response. A central and rate-limiting role in the latter is played by the process of vascularization or neovascularization, so that it is not surprising that in RegMed concepts have been developed for the drug- and gene-delivery of potent stimuli such as vascular-endothelial growth factor (VEGF) to promote neovessel development. However, not all of these novel materials can be tested in vivo and in vitro coculture model systems using human primary cells are being developed to pre-evaluate and determine which of the RegMed concepts exhibit the most promising potential for success after implantation. This review describes some of the growing number of in vitro coculture model systems that are being used to study cell-cell - cell-material interactions at the cellular and molecular level to determine which materials are best suited to integrate into the host, promote a rapid vascularization and fit into the regenerative process without disturbing or slowing the normal healing steps. PMID: 21281686 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Targeting endothelium-pericyte cross talk by inhibiting VEGF receptor signaling attenuates kidney microvascular rarefaction and fibrosis. Am J Pathol. 2011 Feb;178(2):911-23 Authors: Lin SL, Chang FC, Schrimpf C, Chen YT, Wu CF, Wu VC, Chiang WC, Kuhnert F, Kuo CJ, Chen YM, Wu KD, Tsai TJ, Duffield JS Microvascular pericytes and perivascular fibroblasts have recently been identified as the source of scar-producing myofibroblasts that appear after injury of the kidney. We show that cross talk between pericytes and endothelial cells concomitantly dictates development of fibrosis and loss of microvasculature after injury. When either platelet-derived growth factor receptor (R)-β signaling in pericytes or vascular endothelial growth factor (VEGF)R2 signaling in endothelial cells was blocked by circulating soluble receptor ectodomains, both fibrosis and capillary rarefaction were markedly attenuated during progressive kidney injury. Blockade of either receptor-mediated signaling pathway prevented pericyte differentiation and proliferation, but VEGFR2 blockade also attenuated recruitment of inflammatory macrophages throughout disease progression. Whereas injury down-regulated angiogenic VEGF164, the dys-angiogenic isomers VEGF120 and VEGF188 were up-regulated, suggesting that pericyte-myofibroblast differentiation triggers endothelial loss by a switch in secretion of VEGF isomers. These findings link fibrogenesis inextricably with microvascular rarefaction for the first time, add new significance to fibrogenesis, and identify novel therapeutic targets. PMID: 21281822 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | IL-2: A two-faced master regulator of autoimmunity. J Autoimmun. 2011 Jan 29; Authors: Sharma R, Fu SM, Ju ST CD4(+) T-cell (Th) cytokines provide important regulatory and effector functions of T-cells. Among them, IL-2 plays a unique role. IL-2 is required for the generation and maintenance of regulatory T-cells (Treg) to provide lifelong protection from autoimmune disease. Whether IL-2 is also required for autoimmune disease development is less clear as Il2(-/)(-) mice themselves spontaneously develop multi-organ inflammation (MOI). In this communication, we discuss evidence that support the thesis that IL-2 is required for the development of autoimmune response, although some aspects of autoimmune response are not regulated by IL-2. Potential IL-2-dependent mechanisms operating at specific stages of the inflammation process are presented. The interplays among Treg, IL-2, autoimmune response and adaptive immunity are discussed. Overall, available information indicates that IL-2 is a two-faced master regulator of autoimmunity: one to prevent autoimmunity while the other promotes autoimmune response. The latter is an unfortunate consequence of IL-2 function that is used to promote the adaptive immune response against foreign antigens and pathogens. PMID: 21282039 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Tadalafil for the treatment of lower urinary tract symptoms secondary to benign prostatic hyperplasia: Pathophysiology and mechanism(s) of action. Neurourol Urodyn. 2011 Jan 31; Authors: Andersson KE, de Groat WC, McVary KT, Lue TF, Maggi M, Roehrborn CG, Wyndaele JJ, Melby T, Viktrup L BACKGROUND: The PDE5 inhibitor tadalafil is investigation for the treatment of lower urinary tract symptoms (LUTS) in men with benign prostatic hyperplasia (BPH). Several clinical studies of tadalafil and other PDE5 inhibitors have reported significant symptom reduction but limited urinary flow rate improvement. This manuscript reviews the published literature describing the pathophysiology of male LUTS, with an emphasis on mechanisms that may be modulated or improved by phosphodiesterase type 5 (PDE5) inhibition. METHODS: Literature (through March 2010) was obtained via Medline searches and from the individual reviewers files. Articles were selected for review based on describing in vitro, preclinical, or clinical studies of pathological processes contributing to LUTS, or possible effects of PDE5 inhibition in the lower urinary tract. RESULTS: Major mechanisms contributing to LUTS include: reduced nitric oxide/cyclic guanosine monophosphate signaling; increased RhoA kinase pathway activity; autonomic overactivity; increased bladder afferent activity; and pelvic ischemia. Tadalafil and other PDE5 inhibitors have demonstrated beneficial effects on smooth muscle relaxation, smooth muscle and endothelial cell proliferation, nerve activity, and tissue perfusion that may impact LUTS in men. CONCLUSIONS: The pathophysiology of male LUTS is complex and not completely understood. LUTS may occur independently of BPH or secondary to BPH but in both cases involve obstructive or irritative mechanisms with substantial pathophysiological overlap. While the precise mechanism remains unclear, inhibition of PDE5 seems to have an effect on several pathways that may impact LUTS. © 2011 Wiley-Liss, Inc. PMID: 21284024 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Aortic Valve Disease, Treatment, and Regenerative Medicine: On the Cusp of Naturally Inspired Engineering Breakthroughs. Adv Drug Deliv Rev. 2011 Jan 28; Authors: Butcher JT, Mahler GJ, Hockaday LA The aortic valve regulates unidirectional flow of oxygenated blood to the myocardium and arterial system. The natural anatomical geometry and microstructural complexity ensures biomechanically and hemodynamically efficient function. The compliant cusps are populated with unique cell phenotypes that continually remodel tissue for long-term durability within an extremely demanding mechanical environment. Alteration from normal valve homeostasis arises from genetic and microenvironmental (mechanical) sources, which lead to congenital and/or premature structural degeneration. Aortic valve stenosis pathobiology shares some features of atherosclerosis, but its final calcification endpoint is distinct. Despite its broad and significant clinical significance, very little is known about the mechanisms of normal valve mechanobiology and mechanisms of disease. This is reflected in the paucity of predictive diagnostic tools, early stage interventional strategies, and stagnation in regenerative medicine innovation. Tissue engineering has unique potential for aortic valve disease therapy, but overcoming current design pitfalls will require even more multidisciplinary effort. This review summarizes the latest advancements in aortic valve research and highlights important future directions. PMID: 21281685 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | A bioresponsive hydrogel tuned to chondrogenesis of human mesenchymal stem cells. FASEB J. 2011 Jan 31; Authors: Bahney CS, Hsu CW, Yoo JU, West JL, Johnstone B Cartilage tissue engineering aims to replace damaged or diseased tissue with a functional regenerate that restores joint function. Scaffolds are used to deliver cells and facilitate tissue development, but they can also interfere with the structural assembly of the cartilage matrix. Biodegradable scaffolds have been proposed as a means to improve matrix deposition and the biomechanical properties of neocartilage. The challenge is designing scaffolds with appropriate degradation rates, ideally such that scaffold degradation is proportional to matrix deposition. In this study, we developed a bioresponsive hydrogel with cell-mediated degradation aligned to the chondrogenic differentiation of human mesenchymal stem cells (hMSCs). We identified matrix metalloproteinase 7 (MMP7) as an enzyme with a temporal expression pattern that corresponded with cartilage development. By embedding MMP7 peptide substrates within a poly(ethylene glycol) diacrylate backbone, we built MMP7-sensitive hydrogels with distinct degradation rates. When MMP7-sensitive scaffolds were compared with nondegradable scaffolds in vitro, photoencapsulated hMSCs produced neocartilage constructs with more extensive collagenous matrices, as demonstrated through immunohistochemistry and biochemical quantification of matrix molecules. Furthermore, these changes translated into an increased dynamic compressive modulus. This work presents a practical strategy for designing biomaterials uniquely tuned to individual biological processes.-Bahney, C. S., Hsu, C.-W., Yoo, J. U., West, J. L., Johnstone, B. A bioresponsive hydrogel tuned to chondrogenesis of human mesenchymal stem cells. PMID: 21282205 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Improvement of cytokine response and survival time by bioartificial kidney therapy in acute uremic pigs with multi-organ dysfunction. Int J Artif Organs. 2010 Aug;33(8):526-34 Authors: Wang H, Zhang M, Wang X, Mao H, Ying X, Zhu W, Sun C, Jiang C To explore whether bioartificial kidney (BAK) ameliorates cytokine response and biochemical indices, and prolongs the survival time in acute uremic pigs with multiple organ dysfunction syndrome (MODS). PMID: 20872347 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | Co-culture systems for vascularization- learning from Nature. Adv Drug Deliv Rev. 2011 Jan 28; Authors: Kirkpatrick CJ, Fuchs S, Unger RE The endothelial cell (EC) is practically ubiquitous in the human body and forms the inner cellular lining of the entire cardiovascular system. Following tissue injury, the microcirculation becomes the stage for both the inflammatory response and the subsequent healing reaction to restore physiological function to the damaged tissue. The advent of the multidisciplinary field of Regenerative Medicine (RegMed), of which Tissue Engineering (TE) and drug delivery using modern stimuli-responsive or interactive biomaterials are important components, has opened up new approaches to the acceleration of the healing response. A central and rate-limiting role in the latter is played by the process of vascularization or neovascularization, so that it is not surprising that in RegMed concepts have been developed for the drug- and gene-delivery of potent stimuli such as vascular-endothelial growth factor (VEGF) to promote neovessel development. However, not all of these novel materials can be tested in vivo and in vitro coculture model systems using human primary cells are being developed to pre-evaluate and determine which of the RegMed concepts exhibit the most promising potential for success after implantation. This review describes some of the growing number of in vitro coculture model systems that are being used to study cell-cell - cell-material interactions at the cellular and molecular level to determine which materials are best suited to integrate into the host, promote a rapid vascularization and fit into the regenerative process without disturbing or slowing the normal healing steps. PMID: 21281686 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Microcontact printing of fibronectin on a biodegradable polymeric surface for skeletal muscle cell orientation. Int J Artif Organs. 2010 Aug;33(8):535-43 Authors: Altomare L, Riehle M, Gadegaard N, Tanzi MC, Farè S Micropatterning and microfabrication techniques have been widely used to control cell adhesion and proliferation along a preferential direction according to contact guidance theory. One of these techniques is microcontact printing, a soft lithographic technique based on the transfer of a "molecular ink" from an elastomeric stamp to a surface. This method allows the useful attachment of biomolecules in a few seconds on a variety of surfaces with sub-micrometer resolution and control, without modifying the biomolecule properties. The aim of this study is to develop an easy and versatile technique for in vitro production of arrays of skeletal muscle myofibers using microcontact printing technique on biodegradable substrata. PMID: 20872348 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | Age-Related Changes of the Oligodendrocytes in Rat Subcortical White Matter. Anat Rec (Hoboken). 2011 Jan 31; Authors: Chen L, Lu W, Yang Z, Yang S, Li C, Shi X, Tang Y The age-related changes, of the oligodendrocytes in rat subcortical white matter, were investigated in this study. The oligodendrocytes in subcortical white matter were labeled with anti-2',3'-cyclic nucleotide 3'-phosphodiesterase antibody (anti-CNPase antibody, a specific marker of oligodendrocytes). The total number of CNPase(+) cells was estimated with an unbiased stereological technique, the optical fractionator. In this study, we found that the total number of CNPase(+) cells in the young male rats and aged male rats was 14.4 ± 1.2 × 10(6) and 9.0 ± 1.0 × 10(6) , respectively. The total number of the CNPase(+) cells in the subcortical white matter of aged rats was significantly decreased by 37.5% when compared to young male rats. This study demonstrated that there was an aged-related decrease of the oligodendrocytes in subcortical white matter. Anat Rec, 2011. © 2011 Wiley-Liss, Inc. PMID: 21284091 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Effect of surgery to implant motion and force sensors on vertical ground reaction forces in the ovine model. J Biomech Eng. 2011 Feb;133(2):021010 Authors: Herfat ST, Shearn JT, Bailey DL, Greiwe RM, Galloway MT, Gooch C, Butler DL Activities of daily living (ADLs) generate complex, multidirectional forces in the anterior cruciate ligament (ACL). While calibration problems preclude direct measurement in patients, ACL forces can conceivably be measured in animals after technical challenges are overcome. For example, motion and force sensors can be implanted in the animal but investigators must determine the extent to which these sensors and surgery affect normal gait. Our objectives in this study were to determine (1) if surgically implanting knee motion sensors and an ACL force sensor significantly alter normal ovine gait and (2) how increasing gait speed and grade on a treadmill affect ovine gait before and after surgery. Ten skeletally mature, female sheep were used to test four hypotheses: (1) surgical implantation of sensors would significantly decrease average and peak vertical ground reaction forces (VGRFs) in the operated limb, (2) surgical implantation would significantly decrease single limb stance duration for the operated limb, (3) increasing treadmill speed would increase VGRFs pre- and post operatively, and (4) increasing treadmill grade would increase the hind limb VGRFs pre- and post operatively. An instrumented treadmill with two force plates was used to record fore and hind limb VGRFs during four combinations of two speeds (1.0 m/s and 1.3 m/s) and two grades (0 deg and 6 deg). Sensor implantation decreased average and peak VGRFs less than 10% and 20%, respectively, across all combinations of speed and grade. Sensor implantation significantly decreased the single limb stance duration in the operated hind limb during inclined walking at 1.3 m/s but had no effect on single limb stance duration in the operated limb during other activities. Increasing treadmill speed increased hind limb peak (but not average) VGRFs before surgery and peak VGRF only in the unoperated hind limb during level walking after surgery. Increasing treadmill grade (at 1 m/s) significantly increased hind limb average and peak VGRFs before surgery but increasing treadmill grade post op did not significantly affect any response measure. Since VGRF values exceeded 80% of presurgery levels, we conclude that animal gait post op is near normal. Thus, we can assume normal gait when conducting experiments following sensor implantation. Ultimately, we seek to measure ACL forces for ADLs to provide design criteria and evaluation benchmarks for traditional and tissue engineered ACL repairs and reconstructions. PMID: 21280882 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | In-vivo generation of bone via endochondral ossification by in-vitro chondrogenic priming of adult human and rat mesenchymal stem cells. BMC Musculoskelet Disord. 2011 Jan 31;12(1):31 Authors: Farrell E, Both S, Odorfer KI, Koevoet W, Kops N, O'Brien FJ, Baatenburg de Jong RJ, Verhaar JA, Cuijpers V, Jansen J, Erben RG, van Osch GJ ABSTRACT: BACKGROUND: Bone grafts are required to repair large bone defects after tumour resection or large trauma. The availability of patients' own bone tissue that can be used for these procedures is limited. Thus far bone tissue engineering has not lead to an implant which could be used as alternative in bone replacement surgery. This is mainly due to problems of vascularisation of the implanted tissues leading to core necrosis and implant failure. Recently it was discovered that embryonic stem cells can form bone via the endochondral pathway, thereby turning in-vitro created cartilage into bone in-vivo. In this study we investigated the potential of human adult mesenchymal stem cells to form bone via the endochondral pathway. Methods: MSCs were cultured for 28 days in chondrogenic, osteogenic or control medium prior to implantation. To further optimise this process we induced mineralisation in the chondrogenic constructs before implantation by changing to osteogenic medium during the last 7 days of culture. Results: After 8 weeks of subcutaneous implantation in mice, bone and bone marrow formation was observed in 8 of 9 constructs cultured in chondrogenic medium. No bone was observed in any samples cultured in osteogenic medium. Switch to osteogenic medium for 7 days prevented formation of bone in-vivo. Addition of beta-glycerophosphate to chondrogenic medium during the last 7 days in culture induced mineralisation of the matrix and still enabled formation of bone and marrow in both human and rat MSC cultures. To determine whether bone was formed by the host or by the implanted tissue we used an immunocompetent transgenic rat model. Thereby we found that osteoblasts in the bone were almost entirely of host origin but the osteocytes are of both host and donor origin. Conclusions: The preliminary data presented in this manuscript demonstrates that chondrogenic priming of MSCs leads to bone formation in vivo using both human and rat cells. Furthermore, addition of beta-glycerophosphate to the chondrogenic medium did not hamper this process. Using transgenic animals we also demonstrated that both host and donor cells played a role in bone formation. In conclusion these data indicate that in-vitro chondrogenic differentiation of human MSCs could lead to an alternative and superior approach for bone tissue engineering. PMID: 21281488 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | Aortic Valve Disease, Treatment, and Regenerative Medicine: On the Cusp of Naturally Inspired Engineering Breakthroughs. Adv Drug Deliv Rev. 2011 Jan 28; Authors: Butcher JT, Mahler GJ, Hockaday LA The aortic valve regulates unidirectional flow of oxygenated blood to the myocardium and arterial system. The natural anatomical geometry and microstructural complexity ensures biomechanically and hemodynamically efficient function. The compliant cusps are populated with unique cell phenotypes that continually remodel tissue for long-term durability within an extremely demanding mechanical environment. Alteration from normal valve homeostasis arises from genetic and microenvironmental (mechanical) sources, which lead to congenital and/or premature structural degeneration. Aortic valve stenosis pathobiology shares some features of atherosclerosis, but its final calcification endpoint is distinct. Despite its broad and significant clinical significance, very little is known about the mechanisms of normal valve mechanobiology and mechanisms of disease. This is reflected in the paucity of predictive diagnostic tools, early stage interventional strategies, and stagnation in regenerative medicine innovation. Tissue engineering has unique potential for aortic valve disease therapy, but overcoming current design pitfalls will require even more multidisciplinary effort. This review summarizes the latest advancements in aortic valve research and highlights important future directions. PMID: 21281685 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | ROMP-Derived cyclooctene-based monolithic polymeric materials reinforced with inorganic nanoparticles for applications in tissue engineering. Beilstein J Org Chem. 2010;6:1199-205 Authors: Weichelt F, Lenz S, Tiede S, Reinhardt I, Frerich B, Buchmeiser MR Porous monolithic inorganic/polymeric hybrid materials have been prepared via ring-opening metathesis copolymerization starting from a highly polar monomer, i.e., cis-5-cyclooctene-trans-1,2-diol and a 7-oxanorborn-2-ene-derived cross-linker in the presence of porogenic solvents and two types of inorganic nanoparticles (i.e., CaCO(3) and calcium hydroxyapatite, respectively) using the third-generation Grubbs initiator RuCl(2)(Py)(2)(IMesH(2))(CHPh). The physico-chemical properties of the monolithic materials, such as pore size distribution and microhardness were studied with regard to the nanoparticle type and content. Moreover, the reinforced monoliths were tested for the possible use as scaffold materials in tissue engineering, by carrying out cell cultivation experiments with human adipose tissue-derived stromal cells. PMID: 21283558 [PubMed - in process] | | | | | | | | | | | | | | | | | | | | | | | | | Substantial expression of mature elastin in arterial constructs. Proc Natl Acad Sci U S A. 2011 Jan 31; Authors: Lee KW, Stolz DB, Wang Y Mature elastin synthesis is a key challenge in arterial tissue engineering. Most engineered vessels lack elastic fibers in the medial layer and those present are poorly organized. The objective of this study is to increase mature elastin synthesis in small-diameter arterial constructs. Adult primary baboon smooth muscle cells (SMCs) were seeded in the lumen of porous tubular scaffolds fabricated from a biodegradable elastomer, poly(glycerol sebacate) (PGS) and cultured in a pulsatile flow bioreactor for 3 wk. We tested the effect of pore sizes on construct properties by histological, biochemical, and mechanical evaluations. Histological analysis revealed circumferentially organized extracellular matrix proteins including elastin and the presence of multilayered SMCs expressing calponin and α-smooth muscle actin. Biochemical analysis demonstrated that the constructs contained mature elastin equivalent to 19% of the native arteries. Mechanical tests indicated that the constructs could withstand up to 200 mmHg burst pressure and exhibited compliance comparable to native arteries. These results show that nontransfected cells in PGS scaffolds in unsupplemented medium produced a substantial amount of mature elastin within 3 wk and the elastic fibers had similar orientation as those in native arteries. The 25-32 μm pore size supported cell organization and elastin synthesis more than larger pore sizes. To our knowledge, there was no prior report of the synthesis of mature and organized elastin in arterial constructs without exogenous factors or viral transduction. PMID: 21282618 [PubMed - as supplied by publisher] | | | | | | | | | | | | | | | | | | | | | | | | | The all on 4 shelf: mandible. J Oral Maxillofac Surg. 2011 Jan;69(1):175-81 Authors: Jensen OT, Adams MW, Cottam JR, Parel SM, Phillips WR The use of full arch alveolar reduction as an aide to doing All on 4 implant restoration in the mandible is presented. The osteoplasty is described as a flat "shelf" on which to place the restoration. The shelf approach is used to establish optimal implant position and angulation as well as to define anatomy to maximize implant fixation for immediate load prosthetics. PMID: 21055862 [PubMed - indexed for MEDLINE] | | | | | | | | | | | | | | | | | | | | | | | | | Pushing the envelope in biomaterial research: initial results of prosthetic coating with stem cells in a rat model. Surg Endosc. 2010 Nov;24(11):2687-93 Authors: Dolce CJ, Stefanidis D, Keller JE, Walters KC, Newcomb WL, Heath JJ, Norton HJ, Lincourt AE, Kercher KW, Heniford BT Coating prosthetic for hernia repair with a patient's own cells could improve biocompatibility by decreasing inflammation and adhesion formation and by increasing tissue ingrowth and resistance to infection. The objective of this study was to prove the feasibility of prosthetic coating with stem cells and to assess its resistance to adhesion formation when implanted in an animal model. PMID: 20349089 [PubMed - indexed for MEDLINE] | | | | | | | | | |  | |  | |  |
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