Search results for "Neovascularization"
showing 10 items of 351 documents
TMA Vessel Segmentation Based on Color and Morphological Features: Application to Angiogenesis Research
2013
Given that angiogenesis and lymphangiogenesis are strongly related to prognosis in neoplastic and other pathologies and that many methods exist that provide different results, we aim to construct a morphometric tool allowing us to measure different aspects of the shape and size of vascular vessels in a complete and accurate way. The developed tool presented is based on vessel closing which is an essential property to properly characterize the size and the shape of vascular and lymphatic vessels. The method is fast and accurate improving existing tools for angiogenesis analysis. The tool also improves the accuracy of vascular density measurements, since the set of endothelial cells forming a…
Hypoxia in Breast Cancer: Pathogenesis, Characterization and Biological/Therapeutic Implications
2002
Nearly 50% of locally advanced breast cancers exhibit hypoxic and/or anoxic tissue areas that are heterogeneously distributed within the tumour mass. Hypoxia is predominantly caused by structural and functional abnormalities of the newly formed tumour vessels arising from neovascularization, by a disturbed microcirculation, by enlarged diffusion distances, and by tumour-associated or therapy-induced anaemia. The extent of pretherapeutically measured hypoxic tissue areas is independent of clinical tumour size and stage, and histological type and grade. Anaemia can substantially worsen tumour O2 depletion. Hypoxia is known to directly or indirectly confer resistance to irradiation and some ch…
Ductal Carcinoma In Situ of the Breast: A Comparative Analysis of Histology, Nuclear Area, Ploidy, and Neovascularization Provides Differentiation Be…
2002
Ductal carcinoma in situ (DCIS) is a heterogeneous group of lesions that has been subdivided into three types: well differentiated (grade I), moderately differentiated (grade II), and poorly differentiated (grade III). Forty-five cases of DCIS were analyzed for image analysis: nuclear area, DNA ploidy, and vascularization in order to establish a more precise correlation between the histologic grade and these morphometric parameters. Our results confirm that the mean nuclear area, DNA ploidy, and microvessel density (MVD) progressively increased from DCIS grade I to DCIS grade III. The analysis of the nuclear area in relationship to DCIS grading demonstrated a progressive increase of values …
Effect of antiangiogenic treatment on peritoneal endometriosis-associated nerve fibers
2012
Objective To investigate the effect of antiangiogenic treatment on experimental endometriotic lesion nerve fibers. Design Heterologous mouse model of endometriosis. Setting University Institute IVI, University Hospital La Fe. Animal(s) Ovariectomized nude mice (n = 16) receiving human endometrial fragments from oocyte donors (n = 4). Intervention(s) Endometrium fragments stuck in the peritoneum of 5-week-old female nude mice treated with vehicle (n = 8) and antiangiogenic agent cabergoline (n = 8; Cb 2, 0.05 mg/kg/day) for 14 days. Main Outcome Measure(s) Immunofluorescence analysis of von-Willebrand factor (vWF) and vascular smooth muscle cells (αSMA) for evaluating the number of immature …
Sprouting and intussusceptive angiogenesis in postpneumonectomy lung growth: mechanisms of alveolar neovascularization
2013
In most rodents and some other mammals, the removal of one lung results in compensatory growth associated with dramatic angiogenesis and complete restoration of lung capacity. One pivotal mechanism in neoalveolarization is neovascularization, because without angiogenesis new alveoli can not be formed. The aim of this study is to image and analyze three-dimensionally the different patterns of neovascularization seen following pneumonectomy in mice on a sub-micron-scale. C57/BL6 mice underwent a left-sided pneumonectomy. Lungs were harvested at various timepoints after pneumonectomy. Volume analysis by microCT revealed a striking increase of 143 percent in the cardiac lobe 14 days after pneum…
Endothelial capillaries chemotactically attract tumour cells.
2001
Directional migration of capillaries towards tumour implants is generally assumed to be regulated by chemotaxis. Preliminary evidence has also been presented for the existence of a reverse chemotactic signalling pathway, with capillaries attracting tumour cells via paracrine factors. By using a variety of endothelial cell types and tumour cell lines, this study has systematically investigated chemotaxis between endothelial cells and tumour cells in two- and three-dimensional systems. Checkerboard analysis revealed faint attraction of human umbilical vein endothelial cells (HUVECs), but not porcine aortic endothelial cells (PAECs), by tumour cells. In reverse, both PAECs and HUVECs potently …
Dextran sulfate sodium leads to chronic colitis and pathological angiogenesis in Endoglin heterozygous mice
2010
Pathological angiogenesis is an intrinsic component of chronic intestinal inflammation, which results in remodeling and expansion of the gut microvascular bed. Endoglin is essential for endothelial cell function and physiological angiogenesis. In this study we investigated its potential role in the regulation of inflammation by testing the response of Endoglin heterozygous (Eng(+/-)) mice to experimental colitis.C57BL/6 Eng(+/-) and littermate control mice drank water supplemented with 3% dextran sulfate sodium (DSS) for 5 days and were monitored for up to 26 days for clinical signs of colitis. Inflammation, crypt damage, and angiogenic index were scored on histological sections of distal c…
Inflammation-Induced Intussusceptive Angiogenesis in Murine Colitis
2010
Intussusceptive angiogenesis is a morphogenetic process that forms new blood vessels by the division of a single blood vessel into two lumens. Here, we show that this process of intraluminal division participates in the inflammation-induced neovascularization associated with chemically induced murine colitis. In studies of both acute (4-7 days) and chronic (28-31 days) colitis, intravital microscopy of intravascular tracers demonstrated a twofold reduction in blood flow velocity. In the acute colitis model, the decreased velocity was associated with marked dilatation of the mucosal plexus. In contrast, chronic inflammation was associated with normal caliber vessels and duplication (and trip…
Comprehensive three‐dimensional morphology of neoangiogenesis in pulmonary veno‐occlusive disease and pulmonary capillary hemangiomatosis
2019
Abstract Pulmonary veno‐occlusive disease (PVOD) is a rare lung disease characterized by fibrotic narrowing of pulmonary veins leading to pulmonary hypertension (PH) and finally to death by right heart failure. PVOD is often accompanied by pulmonary capillary hemangiomatosis (PCH), a marked abnormal proliferation of pulmonary capillaries. Both morphological patterns often occur together and are thought to be distinct manifestations of the same disease process and accordingly are classified together in group 1′ of the Nice classification of PH. The underlying mechanisms of these aberrant remodeling processes remain poorly understood. In this study, we investigated the three‐dimensional struc…
Automated Measurement of Microcirculatory Blood Flow Velocity in Pulmonary Metastases of Rats
2014
Because the lung is a major target organ of metastatic disease, animal models to study the physiology of pulmonary metastases are of great importance. However, very few methods exist to date to investigate lung metastases in a dynamic fashion at the microcirculatory level, due to the difficulty to access the lung with a microscope. Here, an intravital microscopy method is presented to functionally image and quantify the microcirculation of superficial pulmonary metastases in rats, using a closed-chest pulmonary window and automated analysis of blood flow velocity and direction. The utility of this method is demonstrated to measure increases in blood flow velocity in response to pharmacologi…