Search results for "Bone"
showing 10 items of 2629 documents
Comparison of growth & function of endothelial progenitor cells cultured on deproteinized bovine bone modified with covalently bound fibronectin …
2016
Objectives The objective of this study was to assess and compare the growth and function of Endothelial Progenitor Cells (EPCs) cultured on covalently bonded Vascular Endothelial Growth Factor (VEGF) and covalently bonded Fibronectin (FN) coating on deproteinized bovine bone (DBB) (test samples), compared to non-modified DBB blocks (control sample). Materials and methods The test samples were prepared by plasma polymerization of allylamine onto DBB blocks. Group1 of test samples were prepared with VEGF coating (VEGF-DBB) where as the Group2 test samples were coated with FN (FN-DBB). Non-modified DBB blocks served as a Control. EPCs were isolated and cultivated from buffy coats of peripheral…
Comparative study assessing effects of sonic hedgehog and VEGF in a human co-culture model for bone vascularisation strategies.
2011
The morphogen sonic hedgehog (Shh) seems to mediate adult repair processes in bone regeneration and vascularisation. In this study we investigated the effects of Shh on co-cultures consisting of human primary osteoblasts and outgrowth endothelial cells in terms of angiogenic activation and vessel maturation in comparison to the treatment with the commonly used proangiogenic factor, VEGF. Both, stimulation with VEGF or Shh, leads to an increase in the formation of microvessel-like structures compared to untreated controls. In contrast to VEGF, proangiogenic effects by Shh could already be observed after 24 h of treatment. Nevertheless, after 14 days the angiogenic activity of OEC was compara…
Sonic hedgehog promotes angiogenesis and osteogenesis in a coculture system consisting of primary osteoblasts and outgrowth endothelial cells.
2009
A number of previous studies documented the angiogenic potential of outgrowth endothelial cells in vitro and in vivo and provided evidence that therapeutic success could depend on coculture or coimplantation strategies. Thus, deeper insight into the molecular mechanisms underlying this pro-angiogenic effect of cocultures might provide new translational options for tissue engineering and regenerative medicine. One promising signaling pathway in bone repair involved in neoangiogenesis and bone formation is the sonic hedgehog (Shh) pathway. In this article, we focus on the effect of Shh on the formation of microvessel-like structures and osteoblastic differentiation in cocultures of primary os…
Modification of xenogenic bone substitute materials - effects on the early healing cascadein vitro
2013
Introduction Initial platelet activation with subsequent cytokine release at the defect site plays a crucial role in tissue integration. The aim of this study was to evaluate the influence of topographic and biomimetic collagen modifications of a xenogenic bone substitute material (BSM) on in vitro platelet activation and cytokine release. Material and Methods Three types of xenogenic BSM were used. Two BSM with different levels of granularity (large granule BSM [XBSM/L], small granule BSM [XBSM/S]) and a BSM with collagen (XBSM/C). All three samples were incubated with platelet concentrate of four healthy volunteers at room temperature for 15 min. For all groups, highly thrombogenic collag…
Endothelial progenitor cells: Are they displaying a function in autoimmune disorders?
2016
Endothelial Progenitor Cells (EPCs) are bone marrow derived cells able to differentiate in mature endothelial cells (EC) contributing to the generation of new vessels, connecting to fibronectin, and forming colonies and/or colony forming units. Since circulating EPCs can be actively considered part of endothelial damage in several cardiovascular diseases and autoimmune disorders the possibility to have a measure for endothelium damage should be considered of interest to predict the patient out-come. At the same time the EPCs proliferative and regenerative role could be considered for therapeutic applications. Studies have been performed to elucidate the role of EPCs in Systemic Sclerosis an…
Augmented Reality of the Middle Ear Combining Otoendoscopy and Temporal Bone Computed Tomography
2018
International audience; HYPOTHESIS:Augmented reality (AR) may enhance otologic procedures by providing sub-millimetric accuracy and allowing the unification of information in a single screen.BACKGROUND:Several issues related to otologic procedures can be addressed through an AR system by providing sub-millimetric precision, supplying a global view of the middle ear cleft, and advantageously unifying the information in a single screen. The AR system is obtained by combining otoendoscopy with temporal bone computer tomography (CT).METHODS:Four human temporal bone specimens were explored by high-resolution CT-scan and dynamic otoendoscopy with video recordings. The initialization of the system…
Efficient retrovirus-mediated gene transfer to transplantable human bone marrow cells in the absence of fibronectin
2000
Abstract The low frequency of transplantable hematopoietic stem cells in adult human bone marrow (BM) and other differences from cord blood stem cells have impeded studies to optimize the retroviral transduction of stem cells from adult sources. To address this problem, first a cytokine combination was defined that would both maximize the kinetics of adult BM CD34+CD38− cell mitogenesis and minimize the period of prestimulation required for the transduction of these cells by a MSCV-GFP/neor virus in tissue culture dishes in the absence of fibronectin. Three days of stimulation with flt3-ligand, Steel factor, interleukin (IL)-3, and hyper-IL-6 proved both necessary and sufficient to obtain 8…
“Versus aurei” nella poesia di Walahfrido Strabone
2018
Walahfrido Strabone può essere senz’altro considerato il più importante poeta dell’età carolingia. Vissuto fra l’809 e l’849, egli ha composto alcuni poemetti di vario genere e di diversa tipologia (Visio Wettini, Hortulus, Vita Mammae, Versus de beati Blaithmaic vita et fine, Versus de imagine Tetrici), nonché una gran quantità di carmina che rivelano la sua grande perizia metrica e versificatoria. In questa postilla, dopo una prima parte dedicata allo status degli studi sullo scrittore carolingio, sulla sua vita e sulla sua produzione poetica, si dà particolare risalto a un artificio versificatorio da lui praticato, ossia il ricorso al "versus aureus", la cui frequenza e la cui incidenza …
Vitamin D Sources, Metabolism, and Deficiency: Available Compounds and Guidelines for Its Treatment
2021
Studies on vitamin/hormone D deficiency have received a vast amount of attention in recent years, particularly concerning recommendations, guidelines, and treatments. Moreover, vitamin D’s role as a hormone has been confirmed in various enzymatic, metabolic, physiological, and pathophysiological processes related to many organs and systems in the human body. This growing interest is mostly due to the evidence that modest-to-severe vitamin D deficiency is widely prevalent around the world. There is broad agreement that optimal vitamin D status is necessary for bones, muscles, and one’s general health, as well as for the efficacy of antiresorptive and anabolic bone-forming treatments. Food su…
Clinical effect of vitamin C supplementation on bone healing: A systematic review
2022
Background: The aim of the present systematic review was to evaluate the clinical effect of vitamin C on bone healing after bone fracture or bone reconstruction procedures. Material and Methods: In October 2020, Cochrane Library, Scopus and PubMed-Medline databases were searched without restrictions to identify animal and human studies that fulfilled the eligibility criteria. Outcome measures were bone healing time, bone gain (mm), bone density and adverse events. The risk of bias assessment of the selected studies was evaluated by means of Cochrane Collaboration's Tool for randomized clinical trials, while randomized clinical animal trials were assessed according to SYRCLE's tool. Addition…