References of "Blacher, Silvia"
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See detailImage analysis of pearlite spheroidization based on the morphological characterization of cementite particles
Nutal, Nicolas; Gommes, Cédric ULg; Blacher, Silvia ULg et al

in Image Analysis and Stereology (2010), 29

Pearlite spheroidization is a metallurgical process in steels by which cementite lamellaer decompose into spheroids, a process accompanied by a decrease of the Vickers hardness of the samples. In thi ... [more ▼]

Pearlite spheroidization is a metallurgical process in steels by which cementite lamellaer decompose into spheroids, a process accompanied by a decrease of the Vickers hardness of the samples. In thi study, different methods are compared for measuring cementite particles length and width from scanning electron micrographs. Based on a test-image, a so-called ribbon-like method is proposed for measuring particles length and width, and for discriminating lamellae from spheroids. Differently heat-treated samples are prepared and characterized. The results of analysis are used to rationalize the evolution of the microstructure of the samples. Compared to teh calssical DeHoff shape factor, it is shown that new insight into the spheroidization process is gained by analysing the lamellar length and widh distributions. [less ▲]

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See detailHistological and transcriptional study of angiogenesis and lymphangiogenesis in uninvolved skin, acute pinpoint lesions and established psoriasis plaques: an approach of vascular development chronology in psoriasis
Henno, Audrey ULg; Blacher, Silvia ULg; Lambert, Charles ULg et al

in Journal of Dermatological Science (2010), 57(3), 162-169

Background Dysregulation of angiogenesis and lymphangiogenesis could participate in psoriasis pathogenesis. Analysis of nascent psoriasis lesions should help at identifying early vascular anomalies ... [more ▼]

Background Dysregulation of angiogenesis and lymphangiogenesis could participate in psoriasis pathogenesis. Analysis of nascent psoriasis lesions should help at identifying early vascular anomalies. Objective To analyse vascular development, angiogenesis and lymphangiogenesis markers expression in uninvolved skin in psoriatic patients (N), early psoriasis lesions or pinpoints (PP) and psoriasis plaques (PSO). Methods Skin biopsies were taken in 17 patients in N and in PSO and/or PP. The mRNA steady-state level of angiogenesis and lymphangiogenesis markers was measured by RT-PCR. Immunohistochemistry was performed for von Willebrand factor, podoplanin, Ki-67 and VEGFR3. Blood (BV) and lymphatic (LV) vessels expansion was measured by computer-assisted morphometry. Results Clinical and epidermal aspects indicated that PP are intermediate between N and PSO. While total BV area was already increased in PP similarly to PSO as compared to N, LV area in PP was intermediate between N and PSO. Mean LV size was identical in N and PP and increased in PSO, mean BV size in PP being intermediate between N and PSO. VEGF-A 189 variant was increased in PP as compared to N and PSO. As compared to N, angiogenesis markers (VEGF-A isoforms, PlGF, VEGFR2, NRP-1), VEGF-C and NRP-2 were similarly increased in PP and PSO. Keratin 16 and the lymphangiogenesis markers (VEGFR3, prox-1) were intermediate in PP. Conclusion These data suggest that the expansion of lymphatic vessels occurs after blood vascular development in psoriasis. Expansion of BV in PP could be followed by vessel enlargement during progression to PSO, in parallel with a decreased VEGF-A 189/VEGF-A 121 balance in plaques [less ▲]

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See detailNew Biological Investigations on 3-Bromophenyl 6-Acetoxymethyl-2-oxo-2H-1-Benzopyran-3-Carboxylate as Anti-angiogenic Agent
Hemmer, M.; Kempen, Isabelle; De Tullio, Pascal ULg et al

in Drug Development Research (2010), 71

The development of blood vessels inside tumors is required to provide the nutrients and oxygen needed for tumor growth and to allow the spread of cancer cells at a distance to form metastasis ... [more ▼]

The development of blood vessels inside tumors is required to provide the nutrients and oxygen needed for tumor growth and to allow the spread of cancer cells at a distance to form metastasis. Angiogenesis is also implicated in ocular diseases like age-related macular degeneration. The present work describes the potential anti-angiogenic properties of a coumarinic derivative, 3-bromophenyl 6-acetoxymethyl-2-oxo-2H-1-benzopyran-3-carboxylate (IK9), previously described as a potent inhibitor of HT 1080 fibrosarcoma cell invasion in vitro and tumor growth in vivo. In vivo, ex vivo, and in vitro models were used to delineate the anti-angiogenic properties of IK9. The anti-angiogenic effect of IK9 was demonstrated in vivo in a choroidal neovascularization mice model and additionally ex vivo in a rat aortic ring assay where it was more active than the known matrix metalloproteinase inhibitor Ro 28-2653. IK9 did not affect apoptosis, proliferation, or endothelial cell invasiveness in vitro. These findings suggest a complex mechanism of action of the compound via direct or indirect effects on endothelial cell properties. This study identifies IK9 as a new potent inhibitor of angiogenesis and suggests its potential use as a therapeutic agent. [less ▲]

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See detailPractical Methods for Measuring the Tortuosity of Porous Materials from Binary or Gray-Tone Tomographic Reconstructions
Gommes, Cédric ULg; Bons, Anton-Jan; Blacher, Silvia ULg et al

in AIChE Journal (2009), 55(8), 2000-2012

Two practical methods are proposed to measure the tortuosity of a porous or permeable material from its tomographic reconstruction. The first method is based on the direct measurement of the shortest ... [more ▼]

Two practical methods are proposed to measure the tortuosity of a porous or permeable material from its tomographic reconstruction. The first method is based on the direct measurement of the shortest distance between two points in the pores, and the second is based on the geodesic reconstruction of the pore or permeation space. Unlike the first method, the second can be directly applied to gray-tone tomograms, without the need of a segmentation step. The methods are illustrated with an electron tomogram of clay/plastic nanocomposite, an X-ray microtomogram of sandstone, and a series of model morphologies consisting of penetrable random spheres. For the latter series, the measured tortuosities compare very well with those derived independently from the theoretical effective diffusion coefficients [less ▲]

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See detailEvaluation of the dynamic adsorption of gas on active carbon beds using in situ X-ray µ-tomography coupled with 3D image analysis
Almazan, Maria del Carmen; Léonard, Angélique ULg; Lodewyckx, Peter et al

Poster (2009, June)

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See detail3D characterisation of the structure of activated carbon packed beds using X-ray microtomography
Almazan, Maria del Carmen; Léonard, Angélique ULg; López-Garzón, J. et al

in 3rd International Workshop on Process Tomography (CD Rom) (2009, April)

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See detailWater desorption from resorcinol-formaldehyde hydrogels and adsorption in the resulting xerogels
Escalona, Ivonne; Gommes, Cédric ULg; Job, Nathalie ULg et al

in Microporous and Mesoporous Materials (2009), 117

Water desorption isotherms of resorcinol-formaldehyde (RF) hydrogels and subsequent water adsorption isotherms of the resulting xerogels are determined using the static gravimetric method, at various ... [more ▼]

Water desorption isotherms of resorcinol-formaldehyde (RF) hydrogels and subsequent water adsorption isotherms of the resulting xerogels are determined using the static gravimetric method, at various temperatures. Isotherms obtained from samples synthesized at various pH are compared. Two different mechanisms are involved in RF hydrogels water desorption. At large relative humidity the capillary tension resulting from water removal induces a macroscopic shrinkage of the gel, whereas at low humidity water is evaporated with no network deformation. These two mechanisms are analyzed using a plastic deformation model and the Guggenheim-Anderson-de Boer (GAB) model, respectively. Adsorption isotherms of RF xerogels are analyzed using the GAB model. [less ▲]

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See detailMembrane-Type 4 Matrix Metalloproteinase (MT4-MMP) induces lung metastasis by alteration of primary breast tumor vascular architecture
Chabottaux, Vincent; Ricaud, Stéphanie; Host, Lorin et al

in Journal of Cellular & Molecular Medicine (2009)

The present study aims at investigating the mechanism by which MT4-MMP, a membrane-anchored MMP expressed by human breast tumor cells promotes the metastatic dissemination into lung. We applied ... [more ▼]

The present study aims at investigating the mechanism by which MT4-MMP, a membrane-anchored MMP expressed by human breast tumor cells promotes the metastatic dissemination into lung. We applied experimental (intravenous) and spontaneous (subcutaneous) models of lung metastasis using human breast adenocarcinoma MDA-MB-231 cells overexpressing or not MT4-MMP. We found that MT4-MMP does not affect lymph node colonization nor extravasation of cells from the bloodstream, but increases the intravasation step leading to metastasis. Ultrastructural and fluorescent microscopic observations coupled with automatic computer-assisted quantifications revealed that MT4-MMP expression induces blood vessel enlargement and promotes the detachment of mural cells from the vascular tree, thus causing an increased tumor vascular leak. On this basis, we propose that MT4-MMP promotes lung metastasis by disturbing the tumor vessel integrity and thereby facilitating tumor cell intravasation. [less ▲]

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See detailChorionic Gonadotropin Stimulation of Angiogenesis and Pericyte Recruitment
Berndt, Sarah; Blacher, Silvia ULg; PERRIER d'HAUTERIVE, Sophie ULg et al

in Journal of Clinical Endocrinology and Metabolism (2009), 94(11), 4567-74

During the periimplantation period, human chorionic gonadotropin (hCG) plays a key role by increasing the uterine blood flow through uterine vessel vasodilatation but also through angiogenesis. Indeed, we ... [more ▼]

During the periimplantation period, human chorionic gonadotropin (hCG) plays a key role by increasing the uterine blood flow through uterine vessel vasodilatation but also through angiogenesis. Indeed, we previously demonstrated that hCG contributes to endothelial cell recruitment and vessel formation. OBJECTIVE: In this study, hCG was proposed as an arteriogenic factor that could promote perivascular cell recruitment and vessel stabilization. DESIGN: The aortic ring assay, a three-dimensional ex vivo angiogenesis system mimicking all the steps of the angiogenesis process was used to study the impact of hCG on pericyte recruitment and vessel maturation. SETTING: The study was conducted at a university hospital laboratory. MAIN OUTCOME MEASURES: Perivascular cell proliferation, migration, and apposition were quantified by computerized image analysis. RESULTS: Physiological concentrations of hCG (10-400 IU/ml) significantly enhanced pericyte sprouting and migration and gave rise to the maturation and coverage of endothelial capillaries. In a three-dimensional coculture model of endothelial and perivascular cells, hCG enhanced vessel tube formation and endothelial/mural cell adhesion. In addition, hCG stimulated the proliferation of human umbilical vein endothelial cells and smooth muscle cells. The specificity of these effects was determined by using an anti-hCG blocking antibody. Signaling pathways implicated on this hCG effect is protein kinase A and phospholipase C/protein kinase C dependent for the proliferative effect but only phospholipase C/protein kinase C for the migrative process. CONCLUSIONS: Our findings highlight a novel paracrine role of this early embryonic signal in vessel maturation by stimulating perivascular cell recruitment, migration, and proliferation. [less ▲]

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See detailAdditional parameters for the morphometry of angiogenesis and lymphangiogenesis in corneal flatmounts
Blacher, Silvia ULg; Detry, Benoît ULg; Bruyere, Françoise et al

in Experimental Eye Research (2009), 89(2), 274-276

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See detailEvaluation of the antitumor activity of 16K prolactin
Kinet, Virginie; Nguyen, Ngoc-Quynh-Nhu ULg; Sabatel, Céline et al

Poster (2009)

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See detailAltered expression of angiogenesis and lymphangiogenesis markers in the uninvolved skin of plaque-type psoriasis
Henno, Audrey ULg; Blacher, Silvia ULg; Lambert, Charles ULg et al

in British Journal of Dermatology (2009), 160(3), 581-90

Background Vascular alterations are significant events in the pathomechanism of psoriasis. A disorder in the mechanisms regulating skin angiogenesis and lymphangiogenesis could participate in the ... [more ▼]

Background Vascular alterations are significant events in the pathomechanism of psoriasis. A disorder in the mechanisms regulating skin angiogenesis and lymphangiogenesis could participate in the pathogenesis of the disease. Objectives To quantify differences in the expression of angiogenesis and lymphangiogenesis growth factors, receptors, coreceptors as well as their antagonists in the uninvolved skin of patients with psoriasis compared with the skin of nonpsoriatic volunteers. Methods Skin biopsies were collected from the involved skin of 13 patients with untreated plaque-type psoriasis, from their nonlesional skin at distance from the lesions and from the skin of 16 healthy volunteers. The mRNA steady-state level of keratins 10, 14 and 16, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), vimentin, collagen I and IV, proliferating cell nuclear antigen, the various splice variants of vascular endothelial growth factor, VEGF-A, VEGF-C and VEGF-D, their receptors VEGFR1, VEGFR2 and VEGFR3, neuropilin (NRP)-1 and its soluble forms, NRP-2, semaphorin 3A and prox-1, was measured by reverse transcription–polymerase chain reaction. Immunohistochemistry was performed for Ki-67, von Willebrand factor and D2-40. Blood and lymphatic vessel density, area and distance from epidermis were estimated by morphological analysis coupled to an original computer-assisted method of quantification. Results Skin from healthy volunteers and nonlesional skin from patients with psoriasis displayed similar histological, morphometric and proliferative features. However, a significant overexpression of VEGFR3, the VEGF-A isoform VEGF121, soluble 12 NRP-1 and GAPDH was observed in the nonlesional psoriatic skin as compared with that of normal volunteers. Conclusions These data point to significant differences in the blood and lymphatic vascular transcriptome between the clinically normal-appearing skin of patients with psoriasis and the skin of volunteers without psoriasis. [less ▲]

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See detailContrast-enhanced coded phase-inversion harmonic sonography of knee synovitis correlates with histological vessel density: 2 automated digital quantifications
Kaiser, Marie-Joëlle ULg; Hauzeur, Jean-Philippe ULg; Blacher, Silvia ULg et al

in Journal of Rheumatology (2009), 36(7), 1391-400

OBJECTIVE: To use contrast-enhanced coded phase-inversion harmonic B-mode sonography to assess the acoustic enhancement of the synovial area of the knee; and to compare the data with the histological ... [more ▼]

OBJECTIVE: To use contrast-enhanced coded phase-inversion harmonic B-mode sonography to assess the acoustic enhancement of the synovial area of the knee; and to compare the data with the histological vessel density. METHODS: Eleven patients eligible for a knee arthroscopy were studied. Acoustic quantification was carried out by a digital image analysis program that detects the time-dependent increase [intensity (time) = k x time + C] of gray-level intensity in all the pixels of a specific region of interest (ROI) following intravenous injection of the microbubble contrast agent sulfur hexafluoride. Echo-guided synovial biopsies were carried out in the same ROI. Synovial vessel areas were quantified after Factor VIII immunostaining of synovial biopsies using an automated digital image analysis. RESULTS: Significant (p < 0.05) correlations were observed between histological vessel density and percentage of the synovial area with a k value > 0.01 (r = 0.93) and k(max) values (r = 0.79), as well as between the 2 latter parameters (r = 0.72). The histological vessel density and the 2 acoustic parameters were also significantly correlated with the logarithm of erythrocyte sedimentation rate (r = 0.77, r = 0.87, r = 0.67, respectively) and with log C-reactive protein serum concentration (r = 0.69, r = 0.83, r = 0.62, respectively). CONCLUSION: Contrast-enhanced coded phase-inversion harmonic B-mode sonography coupled with an appropriate data analysis method is a new tool to identify and quantify vessel density in knee synovitis. [less ▲]

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See detailTwo methods of random seed generation to avoid over-segmentation with stochastic watershed: application to nuclear fuel micrographs
Cativa Tolosa, Sebastian; Blacher, Silvia ULg; Denis, Alicia et al

in Journal of Microscopy (2009), 236

A stochastic version of the watershed algorithm is obtained by choosing randomly in the image the seeds from which the watershed regions are grown. The output of the procedure is a probability density ... [more ▼]

A stochastic version of the watershed algorithm is obtained by choosing randomly in the image the seeds from which the watershed regions are grown. The output of the procedure is a probability density function (PDF) corresponding to the probability that each pixel belongs to a boundary. In the present paper, two stochastic seed-generation processes are explored to avoid over-segmentation. The first is a non-uniform Poisson process, the density of which is optimized on the basis of opening granulometry. The second process positions the seeds randomly within disks centered on the maxima of a distance map. The two methods are applied to characterize the grain structure of nuclear fuel pellets. Estimators are proposed for the total edge length and grain number per unit area, LA and NA, which take advantage of the probabilistic nature of the PDF and do not require segmentation. [less ▲]

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See detailX-Ray Microtomography Studies of Tannin-Derived Organic and Carbon Foams
Tondi, G.; Blacher, Silvia ULg; Léonard, Angélique ULg et al

in Microscopy and Microanalysis (2009), 15

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See detailApplication of image analysis in food drying
Jinorose, Maturada; Devahastin, Sakamon; Blacher, Silvia ULg et al

in Ratti, C. (Ed.) Advances in Food Dehydration (2009)

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See detailIn situ follow-up of adsorption in activated carbon beds using X-ray microtomography
Almazan, Maria del Carmen; Léonard, Angélique ULg; Toye, Dominique ULg et al

in Kaskel, S.; Llewellyn, P.; Rodriguez-Reinoso, F. (Eds.) et al Characterisation of Porous Solids VII - Proceedings of the 8th International Symposium on the Characterisation of Porous Solids (2009)

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