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See detailThe CXCL12/CXCR4 pathway or the autocrine proliferative loop of the glioblastoma stem cells
Rogister, Bernard ULiege

in Translational Cancer Research (2017), 6(Suppl 2), 388-390

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See detailCXCL4L1-fibstatin cooperation inhibits tumor angiogenesis, lymphangiogenesis and metastasis.
Prats, A. C.; Van den Berghe, L.; Rayssac, A. et al

in Microvascular Research (2013), 89

Anti-angiogenic and anti-lymphangiogenic drugs slow tumor progression and dissemination. However, an important difficulty is that a tumor reacts and compensates to obtain the blood supply needed for tumor ... [more ▼]

Anti-angiogenic and anti-lymphangiogenic drugs slow tumor progression and dissemination. However, an important difficulty is that a tumor reacts and compensates to obtain the blood supply needed for tumor growth and lymphatic vessels to escape to distant loci. Therefore, there is a growing consensus on the requirement of multiple anti-(lymph)angiogenic molecules to stop cell invasion efficiently. Here we studied the cooperation between endogenous anti-angiogenic molecules, endostatin and fibstatin, and a chemokine, the Platelet Factor-4 variant 1, CXCL4L1. Anti-angiogenic factors were co-expressed by IRES-based bicistronic vectors and their cooperation was analyzed either by local delivery following transduction of pancreatic adenocarcinoma cells with lentivectors, or by distant delivery resulting from intramuscular administration in vivo of adeno-associated virus derived vectors followed by tumor subcutaneous injection. In this study, fibstatin and CXCL4L1 cooperate to inhibit endothelial cell proliferation, migration and tubulogenesis in vitro. No synergistic effect was found for fibstatin-endostatin combination. Importantly, we demonstrated for the first time that fibstatin and CXCL4L1 not only inhibit in vivo angiogenesis, but also lymphangiogenesis and tumor spread to the lymph nodes, whereas no beneficial effect was found on tumor growth inhibition using molecule combinations compared to molecules alone. These data reveal the synergy of CXCL4L1 and fibstatin in inhibition of tumor angiogenesis, lymphangiogenesis and metastasis and highlight the potential of IRES-based vectors to develop anti-metastasis combined gene therapies. [less ▲]

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See detailCXCR4-related increase of circulating human lymphoid progenitors after allogeneic hematopoietic stem cell transplantation
Glauzy, Salomé; André-Schmutz, I; Larghero, J et al

in PLoS ONE (2014), 9(3), 91492

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See detailCXCR7/ACKR3 is activated by chemokines from both CXC and CC subfamilies
Szpakowska, Martyna ULiege; Counson, Manuel; Beaupain, Nadia et al

Poster (2015, June 05)

Detailed reference viewed: 31 (6 ULiège)
See detailCyanidation of Jabali Ag-Zn ore (Yemen)
Bastin, David ULiege

Report (2011)

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See detailCyanide-resistant, ATP-synthesis-sustained, and uncoupling-protein-sustained respiration during postharvest ripening of tomato fruit
Almeida, A.; Jarmuszkiewicz, W.; Khomsi, H. et al

in Plant Physiology (1999), 119

Tomato (Lycopersicon esculentum) mitochondria contain both alternative oxidase (AOX) and uncoupling protein as energy-dissipating systems that can decrease the efficiency of oxidative phosphorylation. We ... [more ▼]

Tomato (Lycopersicon esculentum) mitochondria contain both alternative oxidase (AOX) and uncoupling protein as energy-dissipating systems that can decrease the efficiency of oxidative phosphorylation. We followed the cyanide (CN)-resistant, ATP-synthesis-sustained, and uncoupling-protein-sustained respiration of isolated mitochondria, as well as the immunologically detectable levels of uncoupling protein and AOX, during tomato fruit ripening from the mature green stage to the red stage. The AOX protein level and CN-resistant respiration of isolated mitochondria decreased with ripening from the green to the red stage. The ATP-synthesis-sustained respiration followed the same behavior. In contrast, the level of uncoupling protein and the total uncoupling-protein-sustained respiration of isolated mitochondria decreased from only the yellow stage on. We observed an acute inhibition of the CN-resistant respiration by linoleic acid in the micromolar range. These results suggest that the two energy-dissipating systems could have different roles during the ripening process. [less ▲]

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See detailCyanoacrylate biopsy for cytologic evaluation of the epidermis
ARRESE ESTRADA, Jorge ULiege; QUATRESOOZ, Pascale ULiege; PIERARD-FRANCHIMONT, Claudine ULiege et al

in Hand-book of non-invasive methods and the skin (2005)

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See detailCyanoacrylate skin surface / follicular stripping.
PIERARD, Gérald ULiege; Franchimont, Claudine ULiege; Delvenne, Philippe ULiege et al

in Berardesca, Enzo; Wilhelm, KP; Maibach, H.I. (Eds.) Non invasive diagnostic techniques in clinical dermatology. (2014)

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See detailCyanoacrylate skin surface strippings
PIERARD-FRANCHIMONT, Claudine ULiege; ARRESE ESTRADA, Jorge ULiege; QUATRESOOZ, Pascale ULiege et al

in Textbook of aging skin (2010)

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See detailCyanoacrylate skin surface strippings and the 3S-Bioket advent in tropical dermatology. A look from Liège.
PIERARD, Gérald ULiege; Franchimont, Claudine ULiege; PAQUET, Philippe ULiege et al

in Scientific World Journal (The) (2014), 2014

In the dermatopathology field, some simple available laboratory tests require minimum equipment for establishing a diagnosis. Among them, the cyanoacrylate skin surface stripping (CSSS), formerly named ... [more ▼]

In the dermatopathology field, some simple available laboratory tests require minimum equipment for establishing a diagnosis. Among them, the cyanoacrylate skin surface stripping (CSSS), formerly named skin surface biopsy or follicular biopsy, represents a convenient low cost procedure. It is a minimally invasive method collecting a continuous sheet of stratum corneum and horny follicular casts. In the vast majority of cases, it is painless and is unassociated with adverse events. CSSS can be performed in subjects of any age. The method has a number of applications in diagnostic dermatopathology and cosmetology, as well as in experimental dermatology settings. A series of derived analytic procedures include xerosis grading, comedometry, corneofungimetry, corneodynamics of stratum corneum renewal, corneomelametry, corneosurfametry, and corneoxenometry. [less ▲]

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See detailCyanobacteria - the constructors of travertines?
Kleinteich, Julia; Stelmach Pessi, Igor ULiege; Velazquez, David et al

Conference (2015, February)

Cyanobacteria are participating in carbonate build-up and travertine formation in the Belgian river Hoyoux and its tributaries. In this study, we sampled calcareous material from travertines and oncoliths ... [more ▼]

Cyanobacteria are participating in carbonate build-up and travertine formation in the Belgian river Hoyoux and its tributaries. In this study, we sampled calcareous material from travertines and oncoliths from four sampling sites on the Hoyoux river and Triffoy brook. In addition, the water chemistry was determined. The structure of the material was analyzed by Scanning Electron Microscopy and Raman microscopy (?°. The dominant cyanobacterial species was isolated and identified on the basis of microscopic observation and amplification of the 16S-ITS fragment as Phormidium sp., likely functioning as the ‘architect’ of the travertine system. In order to describe the full diversity of the travertine system and to discriminate between the active fraction and inactive or dead organic matter, DNA as well as RNA was extracted from the travertine material, amplified using cyanobacteria specific primers and sequenced by 454 pyrosequencing. To detect seasonal changes in the biological activity, summer and winter time points were compared. This study reveals the ecology of an overlooked environment in Belgian river systems and tries to explain the build-up of travertines. [less ▲]

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See detailCyanobacteria from benthic mats of Antarctic lakes as a source of new bioactivities
Biondi, Natascia; Tredici, Mario; Taton, Arnaud et al

in Journal of Applied Microbiology (2008), 105(1), 105-115

Aims: To exploit the cyanobacterial diversity of microbial mats growing in the benthic environment of Antarctic lakes for the discovery of novel antibiotic and antitumour activities. Methods and results ... [more ▼]

Aims: To exploit the cyanobacterial diversity of microbial mats growing in the benthic environment of Antarctic lakes for the discovery of novel antibiotic and antitumour activities. Methods and results: In all, 51 Antarctic cyanobacteria isolated from benthic mats were cultivated in the laboratory by optimizing temperature, irradiance and mixing. Productivity was generally very low (£60 mg l)1 d)1) with growth rates (l) in the range of 0Æ02–0Æ44 d)1. Growth rates were limited by photosensitivity, sensitivity to air bubbling, polysaccharide production or cell aggregation. Despite this, 126 extracts were prepared from 48 strains and screened for antimicrobial and cytotoxic activities. Seventeen cyanobacteria showed antimicrobial activity (against the Gram-positive Staphylococcus aureus, the filamentous fungus Aspergillus fumigatus or the yeast Cryptococcus neoformans), and 25 were cytotoxic. The bioactivities were not in accordance with the phylogenetic grouping, but rather strain-specific. One active strain was cultivated in a 10-l photobioreactor. Conclusions: Isolation and mass cultivation of Antarctic cyanobacteria and LCMS (liquid chromatography ⁄ mass spectrometry) fractionation of extracts from a subset of those strains (hits) that exhibited relatively potent antibacterial and ⁄ or antifungal activities, evidenced a chemical novelty worthy of further investigation. Significance and impact of the study: Development of isolation, cultivation and screening methods for Antarctic cyanobacteria has led to the discovery of strains endowed with interesting antimicrobial and antitumour activities. [less ▲]

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See detailCyanobacteria immobilised in porous silica gels: Exploring biocompatible synthesis routes for the development of photobioreactors
Léonard, Alexandre ULiege; Rooke, J. C.; Meunier, C. F. et al

in Energy and Environmental Science (2010), 3(3), 370-377

With the aim of designing photobioreactors (PBR) based on a smart exploitation of microalgae for the production of biofuels and metabolites of interest, this paper describes a novel approach where ... [more ▼]

With the aim of designing photobioreactors (PBR) based on a smart exploitation of microalgae for the production of biofuels and metabolites of interest, this paper describes a novel approach where cyanobacteria are entrapped within highly porous silica matrices. With this concept, it would be possible to work with a constant population of organisms for a continuous (and increased) photoproduction of metabolites, in contrast to "one-shot" uses of liquid cultures. Different hybrid materials based on porous silica gels are described with a special emphasis on finding the most appropriate immobilisation conditions for prolonged cell survival. It is found that an aqueous route based on acid-exchanged sodium silicate combined with the use of silica nanoparticles as a gel-strengthening species shows the best results with a high primary production rate post immobilisation and a preservation of the photosynthetic pigments of up to 35 weeks. Oxygen production, though very low, could be evidenced up to 17 weeks after entrapment, demonstrating the suitability of using porous silica matrices in PBR design. © 2010 The Royal Society of Chemistry. [less ▲]

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See detailCyanobacteria in cold environments
Zakhia, Frederic; Jungblut, Anne-Dorothee; Taton, Arnaud et al

in Margesin, Rosi; Schinner, Frederic; Marx, Jean-Claude (Eds.) et al 'Psychrophiles: from Biodiversity to Biotechnology (2007)

Cyanobacteria evolved under the harsh conditions of the Precambrian and their modern representatives retain a remarkable ability to adapt to and survive within extreme conditions. They dominate ... [more ▼]

Cyanobacteria evolved under the harsh conditions of the Precambrian and their modern representatives retain a remarkable ability to adapt to and survive within extreme conditions. They dominate terrestrial and freshwater cold ecosystems of the Arctic, Antarctic and alpine regions, even though they do not seem to be specifically adapted to optimal growth at low temperatures. They play a major ecological role as they often are primary colonisers of substrates and major primary producers in these ecosystems. The application of molecular tools in combination with classic morphological techniques has begun to provide new insights into the real diversity of cyanobacteria and their biogeographical distribution in cold environments. Our survey of recent studies suggests complex distributional patterns of cyanobacteria, with cosmopolitan, endemic, and habitat-specific genotypes. This ongoing research will help to identify specific geographical areas that have unique microbial communities. However, many more studies are needed to unravel the enormous diversity of cyanobacteria and to better define their biogeographical patterns in cold environments. This is an urgent task in view of the climatic changes that will undoubtedly alter the structure and functioning of microbial communities in polar and alpine ecosystems. [less ▲]

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See detailCyanobacteria in microbial mats of Antarctic lakes (East Antarctica) - A microscopical approach
Taton, Arnaud; Hoffmann, Lucien; Wilmotte, Annick ULiege

in Algological Studies (2008), 168

The cyanobacterial diversity in microbial mats of 56 lakes located in the Larsemann Hills and Bølingen Islands (East Antarctica) was studied by light microscopy. Thirty taxa belonging to 13 genera of ... [more ▼]

The cyanobacterial diversity in microbial mats of 56 lakes located in the Larsemann Hills and Bølingen Islands (East Antarctica) was studied by light microscopy. Thirty taxa belonging to 13 genera of Chroococcales, Oscillatoriales and Nostocales were described. Photomicrographs of the different taxa are provided and their taxonomical assignment as well as their ecology and distribution are discussed. In addition, a semi-quantitative estimation of the abundance of the different morphotypes in the samples was realized and correlated with the mat physiognomy. [less ▲]

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See detailThe Cyanobacterial Biota of Polar Regions: a Molecular Approach
Stelmach Pessi, Igor ULiege

Doctoral thesis (2017)

Cyanobacteria are major components of Polar ecosystems. They comprise a considerable amount of the total biomass, are the main primary producers, and play important roles in the initial development of ... [more ▼]

Cyanobacteria are major components of Polar ecosystems. They comprise a considerable amount of the total biomass, are the main primary producers, and play important roles in the initial development of terrestrial and aquatic habitats. Although the cyanobacterial diversity in the Polar Regions has been well studied, research has been mostly limited to traditional methods such as microscopy, culturing, and Sanger-based molecular ecology approaches. High-troughput sequencing (HTS) has revolutionized our knowledge of microbial diversity and distribution, but a thorough investigation of polar cyanobacterial communities using HTS has not yet been performed. As a result, knowledge of the distributional patterns of polar cyanobacterial communities and the mechanisms underlying their structure is fragmentary. In this thesis, we applied the HTS approach to investigate the diversity and distributional patterns of cyanobacteria in a range of polar habitats. The main goals were: 1. To evaluate the use of HTS as a tool for assessing the cyanobacterial diversity in polar environments, including an assessment of different bioinformatics pipelines and the improvement represented by HTS in comparison to traditional methods; 2. To assess the spatial patterns of cyanobacterial communities across polar environments and the environmental factors shaping cyanobacterial community composition; 3. Tho study the successional dynamics of cyanobacterial communities following the colonization of recently deglaciated habitats. Due to its higher analytical depth, HTS was proven a valuable tool for the study of the cyanobacterial biota of Polar Regions. Nevertheless, the analysis of artificial communities highlighted the importance of strict bioinformatics control of HTS reads, as PCR and sequencing errors might bias the observed structure of the communities. Given the strict bioinformatics workflow applied, our results suggest a previously undetected polar cyanobacterial rare biosphere. On one side, the HTS approach revealed that microbial mat and biological soil crust (BSCs) across different Antarctic and Svalbard (High Arctic) regions are somewhat homogeneous, being dominated by filamentous cyanobacteria from the orders Pseudanabaenales and Oscillatoriales. At the phylotype level (97.5% similarity threshold), on the other hand, cyanobacterial communities were highly variable along environmental gradients within and between habitats. A study of benthic mat communities in Antarctic lakes revealed cyanobacterial communities highly structured by lake conductivity, and comparable compositions in lakes from distant Antarctic regions. In a study of BSC communities in four nunataks and mountain ridges in the Sør Rondane Mountains (Dronning Maud Land), highly dissimilar communities were observed between locations. Finally, two studies of BSC communities in Petunia Bay (Svalbard) revealed a marked, linear cyanobacterial community turnover along gradients of soil development. Altogether, the results obtained in the present thesis show that HTS is a powerful yet underused tool for the study of cyanobacterial diversity, not only in Polar Regions, but also on a global scale. This can be attributed to the very high sequencing depth achieved by HTS, which provides more robust assessments of community turnover and with a stronger statistical support than Sanger- based molecular ecology approaches. [less ▲]

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See detailCYANOBACTERIAL BLOOMS : TOXICITY, DIVERSITY, MODELLING AND MANAGEMENT
Descy, Jean-Pierre; Pirlot, S; Verniers, G et al

Report (2011)

The B-BLOOMS2 project aimed to deepen knowledge of cyanobacterial blooms in Belgium, improve the modelling for prediction and early-warning, develop operational monitoring structures and tools, and ... [more ▼]

The B-BLOOMS2 project aimed to deepen knowledge of cyanobacterial blooms in Belgium, improve the modelling for prediction and early-warning, develop operational monitoring structures and tools, and propose strategies to reduce the impact of cyanobacterial blooms. From a scientific point of view, the research programme focused on: - Collection of physical, chemical, biological and meteorological data on selected reference waterbodies plagued by toxic cyanobacterial blooms in Flanders, Brussels and Wallonia; - Identification and study of the toxigenic cyanobacteria present in the Belgian samples using molecular tools on samples and strains, including genetic diversity and factors regulating their population dynamics; - Measurement of the major cyanotoxins present in the blooms and water samples by analytical methods; - Development and test of management scenarios for control or mitigation of cyanobacterial blooms in one reservoir using integrated watershed models; - Development of a statistical predictive model for a series of urban ponds. From a practical and science policy point of view, B-BLOOMS2 aimed to: - Implement a network of samplers based on existing monitoring programmes of surface waters or on collaboration with health authorities or environmental organisations (BLOOMNET); - Transfer knowledge about methods of monitoring and analysis of blooms to the water/health authorities and environmental organisations by hands-on courses in our laboratories and field sites; - Reinforce the communication to and with authorities and the general population, to raise public awareness, contribute to future guidelines and risk assessment procedures, and improve monitoring and management. [less ▲]

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See detailCyanobacterial community composition in Arctic soil crusts at different stages of development
Pushkareva, Ekaterina; Stelmach Pessi, Igor ULiege; Wilmotte, Annick ULiege et al

in FEMS Microbiology Ecology (2015), 91(12), 143

Cyanobacterial diversity in soil crusts has been extensively studied in arid lands of temperate regions, particularly semi-arid steppes and warm deserts. Nevertheless, Arctic soil crusts have received far ... [more ▼]

Cyanobacterial diversity in soil crusts has been extensively studied in arid lands of temperate regions, particularly semi-arid steppes and warm deserts. Nevertheless, Arctic soil crusts have received far less attention than their temperate counterparts. Here we describe the cyanobacterial communities from various types of soil crusts from Svalbard, High Arctic. Four soil crusts at different development stages (ranging from poorly-developed to well-developed soil crusts) were analysed using 454 pyrosequencing of the V3-V4 variable region of the cyanobacterial 16S rRNA gene. Analyses of 95660 cyanobacterial sequences revealed a dominance of OTUs belonging to the orders Synechococcales, Oscillatoriales, and Nostocales. The most dominant OTUs in the four studied sites were related to the filamentous cyanobacteria Leptolyngbya sp. Phylotype richness estimates increased from poorly- to mid-developed soil crusts and decreased in the well-developed lichenized soil crust. Moreover, pH, ammonium and organic carbon concentrations appeared significantly correlated with the cyanobacterial community structure. [less ▲]

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See detailCyanobacterial Contribution to Travertine Deposition in the Hoyoux River System, Belgium
Kleinteich, Julia; Golubic, Stjepko; Pessi, Igor S. et al

in Microbial Ecology (2017), 74

Travertine deposition is a landscape-forming process, usually building a series of calcareous barriers differentiating the river flow into a series of cascades and ponds. The process of carbonate ... [more ▼]

Travertine deposition is a landscape-forming process, usually building a series of calcareous barriers differentiating the river flow into a series of cascades and ponds. The process of carbonate precipitation is a complex relationship between biogenic and abiotic causative agents, involving adapted microbial assemblages but also requiring high levels of carbonate saturation, spontaneous degassing of carbon dioxide and slightly alkaline pH. We have analysed calcareous crusts and water chemistry from four sampling sites along the Hoyoux River and its Triffoy tributary (Belgium) in winter, spring, summer and autumn 2014. Different surface textures of travertine deposits correlated with particular microenvironments and were influenced by the local water flow. In all microenvironments, we have identified the cyanobacterium Phormidium incrustatum (Nägeli) Gomont as the organism primarily responsible for carbonate precipitation and travertine fabric by combining morphological analysis with molecular sequencing (16S rRNA gene and ITS, the Internal Transcribed Spacer fragments), targeting both field populations and cultures to exclude opportunistic microorganisms responding favourably to culture conditions. Several closely related cyanobacterial strains were cultured; however, only one proved identical with the sequences obtained from the field population by direct PCR. This strain was the dominant primary producer in the calcareous deposits under study and in similar streams in Europe. The dominance of one organism that had a demonstrated association with carbonate precipitation presented a valuable opportunity to study its function in construction, preservation and fossilisation potential of ambient temperature travertine deposits. These relationships were examined using scanning electron microscopy and Raman microspectroscopy. [less ▲]

Detailed reference viewed: 39 (9 ULiège)