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Vessel-like Structure (vessel-like + structure)
Selected AbstractsMultipotency of clonal cells derived from swine periodontal ligament and differential regulation by fibroblast growth factor and bone morphogenetic proteinJOURNAL OF PERIODONTAL RESEARCH, Issue 2 2009K. Shirai Background and Objective:, A blood supply is indispensable for the regeneration of damaged or lost periodontal ligament (PDL) tissue. Mesenchymal stem cell-like activity of cells derived from the PDL has been identified by their capacity to form fibrous and osseous tissue and cementum. However, it remains to be clarified whether the cells have an ability to build the capillary network of blood vessels. This study evaluated the potential of cells derived from the PDL to construct a blood vessel-like structure and examined how growth factors controlled the multipotency of the cells. Material and Methods:, The ability of a swine PDL fibroblast cell line, TesPDL3, to construct a blood vessel-like structure was evaluated on and in the self-assembling peptide scaffold, PuraMatrixTM. In addition, the ability of the cells to form mineralized nodules was evaluated on type I collagen-coated plastic plates. In some cases, fibroblast growth factor (FGF)-2 and bone morphogenetic protein (BMP)-2 were added to these cultures. The status of the expression of vascular and osteoblastic cell-specific markers in the cells was evaluated using reverse transcriptase-polymerase chain reaction (RT-PCR), Western blotting and immunofluorescence analyses. Results:, The TesPDL3 cells not only formed mineralized nodules in response to BMP-2 stimulation but also constructed tube-like structures in response to FGF-2 stimulation. Intriguingly, FGF-2 inhibited the BMP-2-induced formation of mineralized nodules. Conversely, BMP-2 inhibited the FGF-2-induced formation of tube-like structures. Conclusion:, Periodontal ligament fibroblasts have the potential to differentiate not only into osteoblastic but also into vascular cell lineages. The destiny of the cells was reciprocally regulated by BMP-2 and FGF-2. [source] Imaging appearance of the symptomatic perforating artery in patients with lacunar infarction: Occlusion or other vascular pathology?ANNALS OF NEUROLOGY, Issue 2 2001Joanna M. Wardlaw FRCR Lacunar infarction is associated with distinct clinical features. It is thought to result from occlusion of a deep perforating artery in the basal ganglia, centrum semiovale, or brainstem. However, occluded perforating arteries have only rarely been observed at postmortem in patients with lacunar stroke and have not been noted previously on imaging despite the increasing sophistication of the techniques. We observed nine patients with lacunar stroke imaged with computed tomography and magnetic resonance imaging in whom we observed a linear structure with density or signal features consistent with an occluded (or at least abnormal) perforating artery associated with the relevant lacunar infarct. The appearance might also have been caused by a leak of blood and fluid into the perivascular space around the artery, as in several patients the width of the tubular vessel-like structure (>1mm in diameter) was greater than the expected width of a perforating artery (<0.8mm in diameter). This interpretation is supported by the fact that the area of infarction was usually around the abnormal vessel, not at the end of it. We describe the patients' clinical and imaging features, and discuss alternative explanations for the imaging appearance and the implications for gaining insights into the cause of lacunar infarction. [source] A Novel Three-Dimensional In Vitro System to Study Trophoblast,Endothelium Cell InteractionsAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 2 2007Paulomi B. Aldo Introduction Pregnancy complications have been linked to improper trophoblast migration and failure of spiral artery transformation. Endothelial cells play an essential role in directing trophoblast migration and transformation, although by an unknown mechanism. We describe a novel in vitro model to evaluate endothelial,trophoblast interaction and signaling in a three-dimensional system. Method of study Immortalized human endometrial endothelial cell line and first trimester trophoblast cells were co-cultured. Endothelial transformation into vessel-like structures occurred in MatrigelTM OpenLab Image Analysis software was used to monitor labeled trophoblast migration and endothelium transformation. Cytokine/chemokine production was determined using Multiplex. Results Trophoblast migrates toward endothelial cells in Matrigel, aligns on top of the endothelium within 4,8 hr and achieves complete replacement of the endothelium by 72,96 hr. Lipopolysaccharide treatment damages the endothelium and disrupts endothelium,trophoblast interaction. Conclusion We report a novel three-dimensional in vitro and in vivo system of trophoblast,endothelium cell interaction. Significant changes in endothelial cells' phenotype are observed upon differentiation in Matrigel. These changes may be necessary for endothelium to direct trophoblast migration and transformation. [source] A Novel In Vitro Model of Canine Malignant HemangioendotheliomaANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 2005D. Kühn Introduction and Aim:, Canine malignant haemangioendothelioma is an aggressive neoplasia that affects mostly older dogs of large breeds with a strong predilection for the spleen, liver, heart and skin. The tumour originates in the vascular endothelium and consists of transformed cells forming large and leaky vessel-like structures. Prognosis is poor because surgery and chemotherapy have limited success in prolonging survival times and increasing quality of patients. A new strategy to treat this malignancy could be anti-angiogenic therapy based on the inhibition of proliferation, migration and three-dimensional organization of transformed cells. In order to reduce animal experiments, in vitro -models are required to test the safety and efficacy of anti-angiogenic drugs. So far only few models of angiogenesis are available using mostly human, rodent and bovine cells. Therefore, the aim of our study was to establish an in vitro model of canine haemangioendothelioma. Materials and Methods:, Tumours were collected from dogs during surgery or immediately after euthanasia. Isolation of cells was done from different areas of the tumours and by enzymatic digestion of the tissue. Cells were incubated in culture media with and without endothelial growth factors. Cells were characterized by lectin histochemistry using Dolichos biflorus agglutinin, Ulex europaeus agglutinin and Bandeiraea simplicifolia agglutinin I. Moreover, RT-PCR (polymerase chain reaction) was employed to investigate the expression of vascular endothelial growth factor (VEGF) and its endothelium-specific receptors VEGF-R1 and -R2. Results and Conclusions:, Different populations of cells were isolated and cultured successfully from canine malignant haemangioendothelioma. Cells show characteristics of microvascular endothelial cells of an angiogenic phenotype, i.e. the formation of spheroids and tube-like structures as well as strong labelling for Bandeiraea simplicifolia agglutinin I. Thus, morphological and glycohistochemical results confirm the vascular character of the cells isolated. RT-PCR showed expression of VEGF. However, endothelium-specific VEGF receptors were not expressed. Loss of typical receptors is common in cancer and may correlate with increased tumour dedifferentiation. [source] | ||||||||||