Relevant bibliographies by topics / Fucane

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Academic literature on the topic 'Fucane'

Author: Grafiati
Published: 4 June 2021
Last updated: 1 February 2022

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Journal articles on the topic "Fucane"

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Klarzynski, Olivier, Valérie Descamps, Bertrand Plesse, Jean-Claude Yvin, Bernard Kloareg, and Bernard Fritig. "Sulfated Fucan Oligosaccharides Elicit Defense Responses in Tobacco and Local and Systemic Resistance Against Tobacco Mosaic Virus." Molecular Plant-Microbe Interactions® 16, no. 2 (February 2003): 115–22. http://dx.doi.org/10.1094/mpmi.2003.16.2.115.

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Sulfated fucans are common structural components of the cell walls of marine brown algae. Using a fucan-degrading hydrolase isolated from a marine bacterium, we prepared sulfated fucan oligosaccharides made of mono- and disulfated fucose units alternatively bound by α-1,4 and α-1,3 glycosidic linkages, respectively. Here, we report on the elicitor activity of such fucan oligosaccharide preparations in tobacco. In suspension cell cultures, oligofucans at the dose of 200 μg ml−1 rapidly induced a marked alkalinization of the extracellular medium and the release of hydrogen peroxide. This was followed within a few hours by a strong stimulation of phenylalanine ammonia-lyase and lipoxygenase activities. Tobacco leaves treated with oligofucans locally accumulated salicylic acid (SA) and the phytoalexin scopoletin and expressed several pathogenesis-related (PR) proteins, but they displayed no symptoms of cell death. Fucan oligosaccharides also induced the systemic accumulation of SA and the acidic PR protein PR-1, two markers of systemic acquired resistance (SAR). Consistently, fucan oligosaccharides strongly stimulated both local and systemic resistance to tobacco mosaic virus (TMV). The use of transgenic plants unable to accumulate SA indicated that, as in the SAR primed by TMV, SA is required for the establishment of oligofucan-induced resistance.
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Dörschmann, Philipp, Georg Kopplin, Johann Roider, and Alexa Klettner. "Effects of Sulfated Fucans from Laminaria hyperborea Regarding VEGF Secretion, Cell Viability, and Oxidative Stress and Correlation with Molecular Weight." Marine Drugs 17, no. 10 (September 25, 2019): 548. http://dx.doi.org/10.3390/md17100548.

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Background: Sulfated fucans show interesting effects in the treatment of ocular diseases (e.g., age-related macular degeneration), depending on their chemical structure. Here, we compared three purified sulfated fucans from Laminaria hyperborea (LH) regarding cell viability, oxidative stress protection, and vascular endothelial growth factor (VEGF) secretion in ocular cells. Methods: High-molecular-weight sulfated fucan (Mw = 1548.6 kDa, Fuc1) was extracted with warm water and purified through ultrafiltration. Lower-molecular-weight samples (Mw = 499 kDa, Fuc2; 26.9 kDa, Fuc3) were obtained by mild acid hydrolysis of ultrapurified sulfated fucan and analyzed (SEC-MALS (Size-exclusion chromatography-Multi-Angle Light Scattering), ICP-MS, and GC). Concentrations between 1 and 100 µg/mL were tested. Cell viability was measured after 24 h (uveal melanoma cell line (OMM-1), retinal pigment epithelium (RPE) cell line ARPE-19, primary RPE cells) via MTT/MTS (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide/3-(4,5-Dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) assay. Oxidative stress protection was determined after 24 h (OMM-1, ARPE-19). VEGF secretion was analyzed via ELISA after three days (ARPE-19, RPE). Results: Fuc2 and Fuc3 were antiproliferative for OMM-1, but not for ARPE. Fuc1 protected OMM-1. VEGF secretion was lowered with all fucans except Fuc3 in ARPE-19 and RPE. The results suggest a correlation between molecular weight and biological activity, with efficiency increasing with size. Conclusion: The LH sulfated fucan Fuc1 showed promising results regarding VEGF inhibition and protection, encouraging further medical research.
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Fonseca, Roberto, Gustavo Santos, and Paulo Mourão. "Effects of polysaccharides enriched in 2,4-disulfated fucose units on coagulation, thrombosis and bleeding." Thrombosis and Haemostasis 102, no. 11 (2009): 829–36. http://dx.doi.org/10.1160/th08-11-0773.

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SummarySulfated polysaccharides from marine invertebrates have welldefined structures and constitute a reliable class of molecules for structure-activity relationship studies.We tested the effects of two of these polysaccharides,namely a sulfated fucan and a fucosylated chondroitin sulfate, on coagulation, thrombosis and bleeding. The compounds share similar 2,4-disulfated fucose units, which are required for high anticoagulant activity in this class of polymer.These residues occur either as branches in fucosylated chondroitin sulfate or as components of the linear chain in the sulfated fucan.These polysaccharides possess anticoagulant activity but differ significantly in their mechanisms of action.The fucosylated chondroitin sulfate inhibits thrombin by heparin cofactor II, whereas sulfated fucan inhibits thrombin by both antithrombin and heparin cofactor II. In addition, these polysaccharides also have serpin-independent anticoagulant activities. Fucosylated chondroitin sulfate, but not sulfated fucan, activates factor XII. As a result of the complex anticoagulant mechanism, the invertebrate polysaccharides differ in their effects on experimental thrombosis. For instance, the sulfated fucan inhibits venous thrombosis at lower doses than fucosylated chondroitin sulfate. In contrast, fucosylated chondroitin sulfate is significantly more potent than sulfated fucan in arterial thrombosis. Finally, fucosylated chondroitin sulfate increases bleeding, while sulfated fucan has only a discrete effect. In conclusion, the location of 2,4-disulfated fucose units in the polysaccharide chains dictates the effects on coagulation, thrombosis and bleeding.
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Vasconcelos, Ariana, Isabela Sucupira, Alessandra Guedes, Ismael Queiroz, Flavia Frattani, Roberto Fonseca, and Vitor Pomin. "Anticoagulant and Antithrombotic Properties of Three Structurally Correlated Sea Urchin Sulfated Glycans and Their Low-Molecular-Weight Derivatives." Marine Drugs 16, no. 9 (August 30, 2018): 304. http://dx.doi.org/10.3390/md16090304.

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The anticoagulant and antithrombotic properties of three structurally correlated sea urchin-derived 3-linked sulfated α-glycans and their low molecular-weight derivatives were screened comparatively through various in vitro and in vivo methods. These methods include activated partial thromboplastin time, the inhibitory activity of antithrombin over thrombin and factor Xa, venous antithrombosis, the inhibition of platelet aggregation, the activation of factor XII, and bleeding. While the 2-sulfated fucan from Strongylocentrotus franciscanus was observed to be poorly active in most assays, the 4-sulfated fucan from Lytechinus variegatus, the 2-sulfated galactan from Echinometra lucunter and their derivatives showed multiple effects. All marine compounds showed no capacity to activate factor XII and similar low bleeding tendencies regardless of the dose concentrations used to achieve the highest antithrombotic effect observed. The 2-sulfated galactan showed the best combination of results. Our work improves the background about the structure-function relationship of the marine sulfated glycans in anticoagulation and antithrombosis. Besides confirming the negative effect of the 2-sulfated fucose and the positive effect of the 2-sulfated galactose on anticoagulation in vitro, our results also demonstrate the importance of this set of structural requirements on antithrombosis in vivo, and further support the involvement of high-molecular weight and 4-sulfated fucose in both activities.
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Sethi, Poonam. "EXTRACTION AND STRUCTURE ELUCIDATION OF FUCOIDAN FROM MARINE SEAWEED PADINA TETRASTROMATICA HAUCK (PHAEOPHYCEAE)." Chemistry & Material Sciences Research Journal 2, no. 3 (June 23, 2020): 66–70. http://dx.doi.org/10.51594/cmsrj.v2i3.124.

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Seaweeds or the marine macroalgae are one of God’s greatest gift to us through Mother Ocean. The members of Phaeophyceae are exclusively marine and are known for their wide range of diversity and they are rich in cell wall polysaccharide fucoidan and alginate. Fucoidan is a general term for all the fucose-containing polysaccharides from brown seaweeds, while ‘fucan’ will be reserved for the polysaccharide built up with 95% fucose it’s a sulphated polysaccharide. Its highly economical and has abundance applications in the field of pharmaceuticals. Padina tetrastromatica a seaweed abundant in Indian shores was used for the extraction of Fucoidan. Later the structure was elucidated and compared with that of dextran sulphate. This was compared to that of dextran sulphate a standard chemical sulphated polysaccharide while this sulphated polysaccharide is from a natural source.
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Domin, Agnieszka, Tomasz Zabek, Aleksandra Kwiatkowska, Tomasz Szmatola, Anna Deregowska, Anna Lewinska, Artur Mazur, and Maciej Wnuk. "The Identification of a Novel Fucosidosis-Associated FUCA1 Mutation: A Case of a 5-Year-Old Polish Girl with Two Additional Rare Chromosomal Aberrations and Affected DNA Methylation Patterns." Genes 12, no. 1 (January 8, 2021): 74. http://dx.doi.org/10.3390/genes12010074.

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Fucosidosis is a rare neurodegenerative autosomal recessive disorder, which manifests as progressive neurological and psychomotor deterioration, growth retardation, skin and skeletal abnormalities, intellectual disability and coarsening of facial features. It is caused by biallelic mutations in FUCA1 encoding the α-L-fucosidase enzyme, which in turn is responsible for degradation of fucose-containing glycoproteins and glycolipids. FUCA1 mutations lead to severe reduction or even loss of α-L-fucosidase enzyme activity. This results in incomplete breakdown of fucose-containing compounds leading to their deposition in different tissues and, consequently, disease progression. To date, 36 pathogenic variants in FUCA1 associated with fucosidosis have been documented. Among these are three splice site variants. Here, we report a novel fucosidosis-related 9-base-pair deletion (NG_013346.1:g.10233_10241delACAGGTAAG) affecting the exon 3/intron 3 junction within a FUCA1 sequence. This novel pathogenic variant was identified in a five-year-old Polish girl with a well-defined pattern of fucosidosis symptoms. Since it is postulated that other genetic, nongenetic or environmental factors can also contribute to fucosidosis pathogenesis, we performed further analysis and found two rare de novo chromosomal aberrations in the girl’s genome involving a 15q11.1-11.2 microdeletion and an Xq22.2 gain. These abnormalities were associated with genome-wide changes in DNA methylation status in the epigenome of blood cells.
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Domin, Agnieszka, Tomasz Zabek, Aleksandra Kwiatkowska, Tomasz Szmatola, Anna Deregowska, Anna Lewinska, Artur Mazur, and Maciej Wnuk. "The Identification of a Novel Fucosidosis-Associated FUCA1 Mutation: A Case of a 5-Year-Old Polish Girl with Two Additional Rare Chromosomal Aberrations and Affected DNA Methylation Patterns." Genes 12, no. 1 (January 8, 2021): 74. http://dx.doi.org/10.3390/genes12010074.

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Fucosidosis is a rare neurodegenerative autosomal recessive disorder, which manifests as progressive neurological and psychomotor deterioration, growth retardation, skin and skeletal abnormalities, intellectual disability and coarsening of facial features. It is caused by biallelic mutations in FUCA1 encoding the α-L-fucosidase enzyme, which in turn is responsible for degradation of fucose-containing glycoproteins and glycolipids. FUCA1 mutations lead to severe reduction or even loss of α-L-fucosidase enzyme activity. This results in incomplete breakdown of fucose-containing compounds leading to their deposition in different tissues and, consequently, disease progression. To date, 36 pathogenic variants in FUCA1 associated with fucosidosis have been documented. Among these are three splice site variants. Here, we report a novel fucosidosis-related 9-base-pair deletion (NG_013346.1:g.10233_10241delACAGGTAAG) affecting the exon 3/intron 3 junction within a FUCA1 sequence. This novel pathogenic variant was identified in a five-year-old Polish girl with a well-defined pattern of fucosidosis symptoms. Since it is postulated that other genetic, nongenetic or environmental factors can also contribute to fucosidosis pathogenesis, we performed further analysis and found two rare de novo chromosomal aberrations in the girl’s genome involving a 15q11.1-11.2 microdeletion and an Xq22.2 gain. These abnormalities were associated with genome-wide changes in DNA methylation status in the epigenome of blood cells.
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Fonseca, Roberto J. C., and Paulo A. S. Mourão. "Pharmacological Activities of Sulfated Fucose-Rich Polysaccharides after Oral Administration: Perspectives for the Development of New Carbohydrate-Based Drugs." Marine Drugs 19, no. 8 (July 27, 2021): 425. http://dx.doi.org/10.3390/md19080425.

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Marine organisms are a source of active biomolecules with immense therapeutic and nutraceutical potential. Sulfated fucose-rich polysaccharides are present in large quantities in these organisms with important pharmacological effects in several biological systems. These polysaccharides include sulfated fucan (as fucoidan) and fucosylated chondroitin sulfate. The development of these polysaccharides as new drugs involves several important steps, among them, demonstration of the effectiveness of these compounds after oral administration. The oral route is the more practical, comfortable and preferred by patients for long-term treatments. In the past 20 years, reports of various pharmacological effects of these polysaccharides orally administered in several animal experimental models and some trials in humans have sparked the possibility for the development of drugs based on sulfated polysaccharides and/or the use of these marine organisms as functional food. This review focuses on the main pharmacological effects of sulfated fucose-rich polysaccharides, with an emphasis on the antidislipidemic, immunomodulatory, antitumor, hypoglycemic and hemostatic effects.
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Thinh, Pham Duc. "ISOLATION, PURIFICATION AND STRUCTURAL CHARACTERISTICS OF GLYCOSAMINOGLYCANS FROM SEA CUCUMBER STICHOPUS HORRENS." Vietnam Journal of Science and Technology 58, no. 6A (March 31, 2021): 199. http://dx.doi.org/10.15625/2525-2518/58/6a/15527.

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Sea cucumber glycosaminoglycans have been well known as potential anticoagulant and antithrombin agents. In this investigation, glycosaminoglycans were isolated from sea cucumber Stichopus horrens by papain enzymatic digestion. Crude glycosaminoglycans were fractionated and purified by using anion-exchange chromatography on the DEAE-Macro Prep column to give two fractions of fucosylated chondroitin sulfate (FCS1) and fucan sulfate (FS2). Structural characteristics of F1 and F2 fractions were elucidated using chemical and IR, NMR spectroscopic methods. The results showed that the monosaccharide compositions of FCS1 consist of N-Acetyl-Galactosamine (GlcNAc), D-Glucuronic acid (GlcA) and Fucose (Fuc) residues with different molar ratios, while FS2 content only fucose residues. Sulfate contents of FCS1 and FS2 were 47.4% and 48.1%, respectively. FCS1 and FS2 fractions were different in the pattern of sulfation of N-Acetyl-Galactosamine and fucose residues. IR and NMR spectra of two frations showed that sulfate groups were primarily occupied at C4 of pyranose residues in FS2 and C6, C2 and/or C3 of pyranose residues in FCS1 fraction. Our results contributed to knowledge on structural types of glycosaminoglycan from sea cucumbers in Vietnam. The establishment of structural features plays an important role in further studies of the structure-bioactivity relationship of sea cucumber glycosaminoglycan.
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Ustyuzhanina, Nadezhda E., Natalia A. Ushakova, Marina E. Preobrazhenskaya, Maria I. Bilan, Eugenia A. Tsvetkova, Vadim B. Krylov, Natalia A. Anisimova, et al. "Fucoidans as a platform for new anticoagulant drugs discovery." Pure and Applied Chemistry 86, no. 9 (September 19, 2014): 1365–75. http://dx.doi.org/10.1515/pac-2014-0404.

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AbstractAnionic fucose-containing polysaccharides (fucoidans of brown seaweeds, sulfated fucans and fucosylated chondroitin sulfates of invertebrates) are attracting a rapidly growing research interest due to different types of their biological activity discovered in recent years. In particular, algal fucoidans are characterized by large structural variations depending on the species used for their isolation and by the lack of structural regularity due to random distribution of both carbohydrate and non-carbohydrate substituents along the polymer chains. These features make it difficult to find distinct correlations between structural elements and biological properties of polysaccharides. Nevertheless, there is expectation that systematic structural and biochemical studies of fucoidans will form a basis for the development of new drugs. Herewith we summarize our recent results on the influence of fucoidan structure on blood coagulation.
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Dissertations / Theses on the topic "Fucane"

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Gornard, Sophie. "Isolement et caractérisation de bactéries marines associées à l'algue brune Ascophyllum nodosum pour la dépolymérisation enzymatique du fucane." Paris 13, 2002. http://www.theses.fr/2002PA132031.

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Le fucane, constitué de L-fucose sulfaté, est extrait d'algues brunes. Depuis 1987, ce polysaccharide bioactif est étudié par le Laboratoire de Recherches sur les Macromolécules (CNRS, Université Paris 13) et le Centre IFREMER de Nantes dans le cadre de l'unité de Recherche marine n°2. A l'heure actuelle, ses propriètés n'ont jamais étè exploitées à des fins thérapeutiques en raison du manque de connaissance de sa structure fine et des mécanismes moléculaires gouvernant ses activités. L'objectif de ce travail était de développer une approche enzymatique pour la caractérisation de sa structure. Le Centre d'étude et de Valorisation des Algues, désireux de développer un pôle de production d'oligosaccharides, a mis ses moyens techniques à la disposition de ce projet de recherche d'enzymes bactérienne de dégradation du fucane. Nos travaux ont permis de disposer de deux bactéries associées à l'algue Ascophyllum nodosum, nommées B et C, capables de dégrader le fucane. Après optimisation de leurs conditions de culture et de stockage, ces bactéries ont été caractérisées comme appartenant à la famille des Flavobacteriaceae. Elles représentent deux nouvelles espèces bactériennes. Ces bactéries sont capables de produire une activité sulfatase et des fucanases extracellulaires. L'activité fucanase de la bactérie B aurait un mécanisme exolytique et l'activité fucanase de la couche C serait endolyptique. Le niveau d'activité des enzymes extracellulaires étant relativement faible, nous avons recherché des enzymes intracellulaires et périplasmiques chez la souche C. Les résultats obtenus nous ont laissé penser que l'activiité fucanase de cette bactérie serait intracellulaire et pourrait même avoir une localisation périplasmique. La caractérisation des enzymes mises en évidence doit être poursuivie. En effet, ces enzymes purifiées devraient s'avérer utile dans la compréhension des propriètés biologiques du fucane et permettre une modification selective du polysaccharide
Fucan constituted of sulfated L-fucose is extracted from brown seaweeds. Since 1987, this bioactive polysaccharide is studied by the Unity of Marine research n°2 constituted of the Research Laboratory on Macromolecules (CNRS, Paris 13) and IFREMER (Nantes). Currently its properties have never been used for therapeutic purposes. This is partly due to the lack of knowledge about its fine structure and moleculary mecanisms responsible for its activities. The aim of this work was to develoop enzymes for the characterisation of the structure of fucan. The Seaweed Manufacturing Technology Center, inclined to diversify its production of oligosaccharides, made its technical means available for this research about bacterial enzymes able to degrade fucan. Our research enable us to find two bacteria called B and C and associated to the brown seaweed Ascophyllum nodosum, able to degrade fucan. We optimized their culture conditions and their storage. Then we found that these bacteria belonging to the Flavobacteriaceae correspond to two new bacterial species. These bacteria produce an extracellular sulfatase activity and extracellular enzymes responsible for fucan degradation. The fucanase activity of the bacteria B could have an exolytic mecanism and the fucanase activity of the bacteria C could be endolytic. The grade of activity of the extracellular enzymes was low. So we look for intracellular and periplasmic enzymes associated to the bacteria C. The results let us thinks that the fucanase activity of this bacteria could be intracellular and could have a periplasmic localisation. The characterisation of these enzymes should be continued. The purified enzymes should indeed be useful for the understanding of biological properties of the fucan. They could also enable a selective depolymerisation of this polysaccharide
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Dantas, Viviane Wallerstein Mignone. "Papel da fucana sulfatada FucSulf I na interação entre células tumorais e o endotélio in vitro." Universidade do Estado do Rio de Janeiro, 2012. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=5993.

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Para formar metástases, as células tumorais devem se desprender do tumor primário e migrar através do endotélio num processo denominado intravasamento. Uma vez na circulação, elas devem aderir ao endotélio do tecido alvo e extravasar para o novo sítio de colonização, onde irão proliferar. A interação das células tumorais com o endotélio é mediada por selectinas, seguida pela interação com integrinas. As células tumorais apresentam um padrão anormal de glicosilação, expressando ligantes de selectinas, formados por polissacarídeos fucosilados, como sialyl Lewis a/x. Durante o processo metastático, células tumorais secretam diversos fatores de crescimento. Além de modular diferentes tipos celulares que constituem o microambiente tumoral, estes fatores de crescimento também atuam nas células tumorais de forma autócrina, ativando vias de sinalização envolvidas na proliferação e migração celular. Polissacarídeos sulfatados como a heparina, podem atuar como inibidores de P e L-selectinas, além de se ligar a fatores de crescimento, impedindo a ativação de seus receptores. Neste trabalho, avaliamos o papel de fucanas sulfatadas extraídas de diferentes espécies de invertebrados marinhos (L. variegatus, S. franciscanus, S. pallidus, A. lixula e S. droebachiensis) na modulação da interação entre células tumorais com o endotélio in vitro e comparamos seu efeito com o da heparina. Também avaliamos o papel destas moléculas na proliferação de células tumorais. Para isso, utilizamos duas linhagens tumorais de próstata (DU-145 e PC-3) e culturas primárias de células endoteliais de veia umbilical humana (HUVECs). Ao avaliar o efeito das fucanas na adesão das células tumorais às HUVECs, observamos que todas as fucanas testadas inibiram a adesão da linhagem DU-145 à monocamada endotelial, enquanto apenas a fucana extraída da espécie L. variegatus (FucSulf I) e da espécie S. franciscanus inibiram a adesão da linhagem PC-3. A FucSulf I foi uma das fucanas que apresentou maior potencial inibitório nas duas linhagens e foi a única que inibiu a adesão da linhagem DU-145 à matriz subendotelial, não interferindo na adesão da linhagem PC-3. A FucSulf I mostrou-se capaz de diminuir também a migração transendotelial das linhagens tumorais DU-145 e PC-3. A heparina mostrou efeito significativo apenas nos ensaios de transmigração, inibindo este evento de forma similar a FucSuf I. Sabe-se que o VEGF aumenta a permeabilidade endotelial, facilitando a passagem de células tumorais através do vaso. Observamos que as duas linhagens secretam VEGF e que a FucSulf I se liga a este fator. Estes dados sugerem que a interação da FucSuf I com o VEGF pode impedir a ação deste fator nas células endoteliais, diminuindo a migração transendotelial das células tumorais testadas. Também verificamos que a FucSulf I inibiu a proliferação das linhagens celulares na ausência de fatores exógenos ou na presença de soro fetal bovino ou VEGF. Por fim, avaliamos que a FucSulf I interfere na ativação de proteínas específicas de vias de sinalização disparadas por fatores de crescimento. A FucSulf I inibe a ativação da AKT na linhagem PC-3, enquanto nas células DU-145 observamos uma inibição da ativação da ERK. Esses dados indicam que a FucSulf I modula diversas etapas da progressão tumoral e pode ser um potencial candidato para o uso em terapias antitumorais
To form metastasis, tumor cells must detach from primary tumor and migrate through the endothelial cell monolayer in direction of the bloodstream (intravasation). Once in the circulation, tumor cells must be able to adhere and migrate across the endothelium (extravasation) towards the target organ, where they will proliferate. Interaction between endothelial and tumor cells is mediated by selectins, followed by the interaction with integrins. Cancer cells frequently exhibit abnormal glycosylation patterns, resulting in the expression of selectins ligands formed by fucosylated polysaccharides, such as sialyl Lewis a/x. During metastatic process, tumor cells secrete several growth factors which can modulate different cell types that are present in the tumor microenvironment. These growth factors can also mediate autocrine signaling and activate signaling pathways involved in tumor cell proliferation and migration. Sulfated polysaccharides, as heparin, may act as P and E-selectin inhibitors as they may also bind to growth factors and interfere in their receptor activation. In this present work, we evaluated the role of sulfated fucans extracted from different marine invertebrates species (L. variegates, S. franciscanus, S. pallidus, A. lixula e S. droebachiensis) in the modulation of the interaction between tumor and endothelial cells in vitro and compared their effect with heparin. We also investigated the role of these molecules in the proliferation of tumor cells. For that, we used two prostate tumor cell lines (DU-145 and PC-3) and a primary culture of human umbilical vein endothelial cells (HUVECs). We first evaluated the effect of the fucans in the tumor cell adhesion to HUVECs. All fucans tested were able to inhibit the interaction between DU-145 and the endothelial cells, while only fucans extracted from L. variegates (FucSulf I) and S. franciscanus were able to inhibit the adhesion of PC-3. FucSulf I showed one of the most striking inhibitory effects in both cell lines and was the only one that inhibited adhesion of DU-145 to subendothelial matrix. It didnt interfere with the adhesion of PC-3 to subendothelial matrix. FucSulf I was also able to decrease transendothelial migration of DU-145 and PC-3. Heparin had significant effect only in the transmigration assays, showing a similar inhibitory potencial in comparison with FucSulf I. VEGF increases endothelial permeability, thus facilitating the migration of tumor cells through the endothelial barrier. We observed that both tumor cell lines secrete VEGF and FucSulf I binds to this factor. These data suggest that the interaction between FucSulf I and VEGF may interfere in endothelial cells response to VEGF, and decrease transendothelial migration of tumor cells. We also showed that FucSulf I inhibits tumor cell proliferation in the absence of exogenous growth factors or in the presence of fetal bovine serum or VEGF. At least, we showed that FucSulf I interfered in the activation of specific proteins involved in signaling pathways triggered by growth factors. FucSulf I inhibited the activation of AKT in PC-3 tumor cell line, while inhibited the activation of ERK in DU-145 tumor cell line. These results indicate that FucSulf I modulates several steps of tumor progression and may be a potential candidate for use in antitumor therapies
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Silva, Ana Katarina Andrade. "Efeito antiinflamat?rio de fucana extra?da da alga Parda spatoglossum schroederii em modelos experimentais de Peritonite, choque n?o s?ptico e colite." Universidade Federal do Rio Grande do Norte, 2012. http://repositorio.ufrn.br:8080/jspui/handle/123456789/13084.

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Fucans is a name used for sulfated polysaccharides, which is most characteristic structure of the presence of sulfated L-fucose, are found in brown seaweed (Phaeophyceae) and echinoderms (sea urchins and sea cucumbers). These polysaccharides have been reported to possess anticoagulant, antitumor, anti-viral, anti-proliferative and anti-inflammatory activities. Therefore, in the present study was evaluate the effect of the fucan from the brown seaweed Spatoglossum schroederii in models of peritonitis and non-septic shock induced by zymosan, as well as in a murine model of colitis induces by DSS. So, the mice treatment by intravenous route with the fucan was able to reduce the exudate formation and the cell migration in the model of acute peritonitis induced by zymosan during the kinetic of 6, 24 and 48 hours. Similarly, in the model of non-septic shock induced by zymosan the fucan demonstrated a protector effect to inhibited the cellular migration to the peritoneo, to decrease the levels of IL-6 in the serum and in the peritoneal exudate, to attenuate the lose of weight in the mice; beside to reduce the serum levels of hepatic transaminases and as well as the liver injury. In the model of murine colitis, the treatment with the fucan reduced the lose of weight of the animals, decreased the levels of IL-17 and IFN- produced in the gut and decrease the intestinal lesion induced by DSS. In conclusion, the fucan used in this study presented a significant protector effect in the murine models of inflammation
Fucana ? uma denomina??o utilizada para polissacar?deos sulfatados, que tem como caracter?stica estrutural mais marcante a presen?a de L-fucose sulfatada, sendo encontrados em algas pardas (Phaeophyceae) e em equinodermos (ouri?os e pepinos do mar). Esses polissacar?deos tem sido descritos por possuir atividade anticoagulante, anti-tumoral, anti-viral, antiproliferativa e anti-inflamat?ria. Portanto, no presente estudo foi avaliado o efeito da fucana da alga parda Spatoglossum schroederii em modelos de peritonite e choque n?o s?ptico induzido por zimosan, bem como em um modelo murino de colite induzida por DSS. Dessa forma, o tratamento de camundongos pela via intravenosa com a fucana foi capaz de reduzir a forma??o do exsudato e a migra??o celular no modelo de peritonite aguda induzida por zimosan durante a cin?tica de 6, 24 e 48 horas. De maneira semelhante, no modelo de choque n?o-s?ptico induzido por zimosan a fucana demonstrou efeito protetor ao inibir a migra??o celular para o perit?nio, diminuir os n?veis de IL-6 s?rico e no exsudato peritoneal, ao atenuar a perda de peso do animais, al?m de reduzir os n?veis s?ricos das transaminases hep?ticas, assim como a les?o no f?gado. No modelo murino de colite, o tratamento com a fucana reduziu a perda de peso dos animais, diminuiu os n?veis de IL-17 e IFN- produzidos no intestino e diminuiu a les?o intestinal ocasionada pela DSS. Conclui-se ent?o, que a fucana usada nesse estudo apresentou efeito protetor significativo diante dos modelos murinos de inflama??o
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Dore, Celina Maria Pinto Guerra. "Aspectos estruturais, farmacol?gicos e biol?gicos de fucanas da alga marrom sargassum vulgare." Universidade Federal do Rio Grande do Norte, 2012. http://repositorio.ufrn.br:8080/jspui/handle/123456789/12570.

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Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico
The present study examines the chemical composition and their effects on free radicals, inflammation, angiogenesis, coagulation, VEGF effects and cellular proliferation of a polysaccharides from alga Sargassum vulgare. The sulfated polysaccharide was extracted from brown seaweed by proteolysis with enzymes maxataze. The presence of proteins and sugars were observed in crude polysaccharides. Fractionation of this crude extract was made with growing concentration of acetone (0.3-1.5 v) and produced four groups of polysaccharides. Anionic polysaccharides from brown seaweed Sargassum vulgare, SV1and PSV1 were fractionated (SV1) and purified (PSV1), and displayed with high total sugars and sulfate content and very low level of protein. This fucan SV1 contains low levels of protein and high carbohydrate and sulfate content. This polysaccharides prolonged activated partial thromboplastin time (aPTT) at 50 μg (>240 s). SV1 was found to have no effect on prothrombin time (PT), corresponding to the extrinsic pathway of coagulation. SV1 exhibits high antithrombotic action in vivo, with a concentration ten times higher than heparin. Polysaccharides from S. vulgare promoted direct inhibition enzymatic activity of thrombin and stimulated enzymatic activity of FXa. SV1 showed optimal inhibitory activity of thrombin (50.2?0.28%) at a concentration of 25 μg/mL. Its antioxidant action on scavenging radicals by DPPH was (22%), indicating the polymer has no cytotoxic action (hemolytic) on ABO and Rh blood types in different erythrocyte groups and displays strong anti-inflammatory action on all concentrations tested in the carrageenan-induced paw edema model, demonstrated by reduced edema and cellular infiltration. Angiogenesis is a dynamic process of proliferation and differentiation. It requires endothelial proliferation, migration, and tube formation. In this context, endothelial cells are a preferred target for several studies and therapies. The antiangiogenic efficacy of polysaccharides was examined in vivo in the chick chorioallantoic membrane (CAM) model by using fertilized eggs. Decreases in the density of the capillaries were assessed and scored. The results showed that SV1 and PSV1 have an inhibitory effect on angiogenesis. These results were also confirmed by inhibition tubulogenesis in rabbit aorta endothelial cell (RAEC) in matrigel. These compounds were assessed in Apoptosis assay (Annexin V - FITC / PI) and cell viability by MTT assay of RAEC. These polysaccharides do not affect the viability and do not have apoptotic or necrotic action. RAEC cell when incubated with SV1 and PSV1showed inhibition of VEGF secretion, observed when compounds were incubated at 25, 50 and 100 μg/μL. The VEGF secretion with the RAEC cell line for 24 h, was more effective for PSV1 at 50 μg/μL(71.4%) than SV1 100 μg/μL (75.9%). SV1 and PSV1 had an antiproliferative action (47%) against tumor cell line HeLa. Our results indicate that these sulfated polysaccharides have antiangiogenic and antitumoral actions
O presente estudo analisa a composi??o qu?mica e seus efeitos sobre os radicais livres, inflama??o, angiog?nese, coagula??o, VEGF e prolifera??o celular dos polissacar?deos de uma alga Sargassum vulgare. O polissac?rido sulfatado foi extra?do a partir de algas marrons por prote?lise com a enzima maxataze. A presen?a de prote?nas e a??cares foram observados no cru de polissacarideos. Fracionamento do o extrato bruto foi feito com concentra??es crescente de acetona (0,3-1,5 v), produzindo quatro grupos de polissacarideos. Estes compostos ani?nicos da alga S. vulgare, foram fracionados (SV1) e purificados (PSV1) exibindo com alta a??cares totais e sulfatecontent e n?vel muito baixo de prote?nas.A fucana SV1 cont?m baixos n?veis de prote?na e de hidratos de carbono e alto teor de sulfato. Este polissacar?deos prolongou o tempo de tromboplastina parcial activada (aPTT) a 50 ug (>240 s). n?o foi observado qualquer efeito de SV1 sobre o tempo de protrombina (PT), que corresponde a via extr?nseca da coagula??o. SV1 exibiu alta a??o antitromb?tica in vivo, com uma concentra??o 10 vezes maior do que a heparina. SV1 promoveu a actividade de inibi??o enzim?tica direta da trombina e estimulou a atividade enzim?tica do FXa. Mostrou tamb?m, atividade inibidora optima de trombina (50,2 ? 0,28%) a uma concentra??o de 25 ug / mL. A sua ac??o anti-oxidante de radicais scavenging por DPPH foi de (22%), indicando que o pol?mero n?o tem qualquer a??o citot?xica (hemol?tica) em tipos de sangue ABO e Rh, em diferentes grupos de eritr?citos e exibindo alta a??o anti-inflamat?ria em edema de pata de ratos Wistar em todas as concentra??es testadas induzida por carragenina. Tal processo foi demonstrado por edema e infiltra??o celular. A angiogenese ? um processo din?mico de prolifera??o e diferencia??o. Ele requer prolifera??o endotelial, migra??o, e a forma??o do tubo. Neste contexto, as c?lulas endoteliais s?o um alvo preferido para muitos estudos e terapias. A efic?cia antiangiogenico de polissacar?deos foi examinada in vivo na membrana corioalant?ica pinto (CAM) usando-se ovos fertilizados. Diminui??es na densidade dos capilares foram avaliados e pontuados. Os resultados mostraram que SV1 e PSV1 tem um efeito inibidor da angiogenese. Estes resultados foram tamb?m confirmados por tubulogenesis inibi??o na c?lula endotelial da aorta de coelho (RAEC) em matrigel. C?lulas RAEC quando foram incubadas com SV1and PSV1 demonstraram inibi??o da secre??o de VEGF, a 25, 50 e 100 ug/mL. A secre??o de VEGF com a linha de c?lulas RAEC durante 24 h, foi mais eficaz para PSV1 a 50 ug / mL (71,4%) do que SV1 100 ug / mL (75,9%). SV1 e PSV1 posuiram uma ac??o antiproliferativa (47%) contra as c?lulas tumorais tipo HeLa. Estes compostos foram avaliados tamb?m, no ensaio de apoptose (anexina V - FITC / PI) e a viabilidade celular pelo ensaio de MTT de RAEC. Estes polissacar?deos n?o afetaram a viabilidade e n?o tiveram a??o apopt?tica ou necr?tica. Nossos resultados indicam que estes polissacar?deos sulfatados t?m a??es antiangiog?nica e antitumoral e constituem um importante alvo biol?gico e farmacol?gico
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Marques, Cybelle Teixeira. "?Atividade antiinflamat?ria de uma heterofucana da alga marrom Padina gymnospora." Universidade Federal do Rio Grande do Norte, 2007. http://repositorio.ufrn.br:8080/jspui/handle/123456789/18531.

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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior
?Fucans, sulfated polysaccharides extracted from brown algae and some echinoderms, have been extensively studied for its diverse biological activities and because of its interference with molecular mechanisms of cell to cell recognition, including leukocyte trafficking from blood vessels into sites of inflammation mediated by selectin, a family of adhesion molecules. In the present study, we examined structural features of a heterofucan extracted from brown algae Padina gymnospora and its effect on the leukocyte migration to the peritoneum. The sulfated polysaccharides were extracted from the brown seaweed by proteolysis with the proteolytic enzyme maxatase. The presence of protein and uronic acid contamination was detected in the crude polysaccharide extract. Fractionation of the crude extract with growing concentrations of acetone produced five fractions with different concentrations of fucose, xylose, uronic acid, galactose, glucose and sulfate. The fraction precipitated with 1.5 volumes of acetone was characterized by infrared and nuclear magnetic resonance, through which can be observed the presence of sulfate groups in the C4 of -L-fucose. The anti-inflammatory action of this composite was assessed by a sodium thioglycollate-induced peritonitis assay and through nitric oxide production by the peritoneal macrophages using Griess reagent. Fraction F1.5 was efficient in reducing leukocyte influx into the peritoneal cavity when 10 mg/kg and 25mg/kg were used, resulting in a decrease of 56 and 39%, respectively. A decrease of nitric oxide production occurred when high concentrations of fucana were used. The cytotoxicity of the composite was also assessed using the reduction of 3-(4,5 dimethylthiazol-2-yl) 2,5-diphenyltetrazolium bromide (MTT). Fraction F1.5 had no cytotoxicity when 500 ?g/mL of the fraction was used. This study suggests the use of fraction F1.5 (heterofucan) as an anti-inflammatory
Fucanas, polissacar?deos sulfatados extra?dos de alga marrom e alguns equinodermos, t?m sido extensivamente estudadas devido as suas diversas atividades biol?gicas e pela sua interfer?ncia com mecanismos moleculares de reconhecimento celular, incluindo o tr?fego de leuc?citos dos vasos sangu?neos para o interior de s?tios inflamat?rios mediado pela fam?lia das mol?culas de ades?o denominada selectinas. Neste presente estudo, n?s examinamos a estrutura de uma heterofucana extra?da da alga marrom Padina gymnospora e seu efeito sobre a migra??o de leuc?citos para o perit?nio. Os polissacar?deos sulfatados foram extra?dos da alga marrom por prote?lise com a enzima proteol?tica maxatase. A presen?a de contamina??o por prote?nas e ?cido ur?nico foi detectada no extrato bruto dos polissacar?deos. Fracionamento do extrato bruto com concentra??es crescentes de acetona produziu cinco fra??es com diferentes concentra??es de fucose, xilose, ?cido ur?nico, galactose, glicose e sulfato. A fra??o precipitada com 1,5 volume de acetona foi caracterizada por infravermelho e resson?ncia magn?tica nuclear, atrav?s das quais se p?de constatar a presen?a de grupos sulfato no C4 da -L-fucose. A a??o antiinflamat?ria deste composto foi avaliada atrav?s do ensaio de peritonite induzida por tioglicolato de s?dio e atrav?s da produ??o de ?xido n?trico por macr?fagos peritoneais utilizando-se o reagente de Griess. A fra??o F1,5 mostrou-se eficiente na redu??o do influxo leucocit?rio para a cavidade peritoneal quando utilizados 10 mg/Kg e 25 mg/Kg resultando em uma diminui??o na ordem de 56 e 39 %, respectivamente. Uma diminui??o na produ??o de ?xido n?trico ocorreu quando altas concentra??es de fucana foram usadas. A citotoxicidade do composto tamb?m foi avaliada utilizando-se como par?metro a redu??o do 3-(4,5- dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). A fra??o F1,5 n?o apresentou citotoxicidade quando utilizados 500 ?g/ml da fra??o. Este estudo sugere o uso da fra??o F1,5 (heterofucana) como um antiinflamat?rio
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6

Boyen, Catherine. "Etude de la paroi cellulaire des pheophycees : approche physicochimique et immunocytologique, preparation d'enzymes de degradation specifiques." Paris 6, 1987. http://www.theses.fr/1987PA066281.

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Etude de la composition osidique d'alginate des genres pelvetia, fucus, arcophyllum, sargassum et laminaria. Preparation et caracterisation des alginates-lyases a partir de divers mollusques marins et d'une bacterie marine. Etude comparee de la regeneration de la paroi du protoplaste et de la mise en place normale de la paroi du zygote de fucus distichus par marquage avec des anticorps monoclonaux
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LIRA, Mariane Cajubá de Britto. "Estudo da utilização da Fucana como agente de direcionamento de nanopartículas para macrófagos." Universidade Federal de Pernambuco, 2009. https://repositorio.ufpe.br/handle/123456789/1322.

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Faculdade de Amparo à Ciência e Tecnologia do Estado de Pernambuco
O objetivo do presente trabalho foi inicialmente extrair e purificar o polissacarídeo fucana proveniente do Sargassum cymosum e utilizá-lo como agente de direcionamento de nanopartículas para macrófagos. A caracterização do material extraído e purificado foi efetuada utilizando análise elementar, espectroscopia de infravermelho (IV), ressonância magnética nuclear de hidrogênio (RMN H1) e análise térmica e a determinação da massa molecular foi efetuada por cromatografia de permeação em gel. Em seguida, o material obtido foi utilizado na preparação das novas nanopartículas de Poli(cianoacrilato de isobutila) revestidas de fucana (FC-PIBCA-NP). As nanopartículas foram obtidas através da polimerização por emulsão aniônica (AEP) e polimerização por radicais redox (RREP) utilizando mistura de dextrana e fucana em diferentes proporções. As nanopartículas foram caracterizadas através do tamanho, potencial zeta, morfologia e estabilidade a longo prazo. Nanopartículas estáveis foram obtidas com até 100% de fucana pelo método AEP. Por outro lado, suspensões estáveis de nanopartículas foram obtidas com no máximo 25% de fucana por RREP. As suspensões obtidas com porcentagem mais elevadas de fucana não permaneceram estáveis. O potencial zeta das nanopartículas diminuiu com o aumento da quantidade de fucana, alcançando o valor de 44 mV para as nanopartículas preparadas por AEP com 100% de fucana. Estes resultados indicam que a fucana permanece localizada na superfície das nanopartículas. A análise morfológica por microscopia eletrônica de varredura (MEV) e microscopia eletrônica de transmissão (MET) mostrou nanopartículas com forma esférica. A estrutura interna das nanopartículas do tipo núcleo-coroa foi mostrada claramente por análise MET o que está de acordo com os resultados do potencial zeta que sugerem a localização do polissacarídeo na superfície das nanopartículas. As interações das nanopartículas com a linhagem celular de macrófagos J774 e com fibroblastos NIH-3T3 foram investigadas pela avaliação da citotoxicidade e pela observação da captura celular por microscopia confocal de fluorescência. As nanopartículas preparadas pelo método AEP mostraram uma maior citotoxicidade em macrófagos. Por exemplo, as nanopartículas obtidas pelo método AEP contendo 25% de fucana mostraram-se 3 vezes mais citotóxicas em macrófagos J774 comparadas às nanopartículas RREP (IC50 = 4 ± 2μg/mL e IC50 11 ± 3μg/mL, respectivamente). As observações efetuadas por microscopia confocal de fluorescência para avaliar a captura e a distribuição das nanopartículas nas células não permitiram explicar o aumento da citotoxicidade das nanopartículas obtidas pelo método AEP nos macrófagos. Todos os tipos de nanopartículas foram encontradas nos dois tipos de células, demonstrando que elas podem ser capturadas independentemente pelos macrófagos e fibroblastos. As diferenças na aparência da fluorescência no interior das células, i.e., pontual ou difusa, sugerem que as nanopartículas penetraram nas células por mecanismos distintos. No entanto, nenhuma correlação pode ser estabelecida entre o tipo de nanopartículas (AEP ou RREP) e o teor de fucana. As nanopartículas foram administradas em ratos por via oral com objetivo de investigar se elas poderiam ser direcionadas para os macrófagos do tecido linfóide intestinal. As propriedades bioadesivas e localização no tecido intestinal das nanopartículas fluorescentes foram investigadas por microscopia de fluorescência. Somente as nanopartículas revestidas com fucana obtidas pelo método RREP apresentaram uma redução na bioadesão comparada aos outros tipos de nanopartículas. A análise por microscopia de fluorescência revelou que as nanopartículas foram principalmente encontradas associadas ao muco residual. Apenas uma pequena quantidade de nanopartículas pôde ser visualizada na superfície das células epiteliais, do lado da luz intestinal onde estão localizadas as vilosidades e as placas de Peyer. Esses resultados sugerem a retenção das nanopartículas no muco e que uma pequena quantidade de nanopartículas chega à superfície do epitélio para ser eventualmente capturada pelos macrófagos. Embora o presente trabalho tenha permitido realizar a extração da fucana e a preparação de nanopartículas de PIBCA revestidas com fucana, não foi capaz, no entanto, de demonstrar que as novas nanopartículas podem ser utilizadas para aumentar a especificidade e direcionamento para macrófagos. Experimentos complementares serão, portanto, necessários para melhor compreender a origem da citotoxicidade das nanopartículas obtidas pelo método AEP em macrófagos J774. Além do mais, para o direcionamento das nanopartículas para macrófagos presentes em mucosas, as propriedades bioadesivas precisam ser ajustadas com vistas a reduzir a retenção pelo muco e de permitir um maior alcance na quantidade de nanopartículas a atingir a superfície das células epiteliais
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PEDEN, MICHEL. "Les medicaments issus des algues : utilisation potentielle en therapeutique humaine." Rennes 1, 1993. http://www.theses.fr/1993REN1M155.

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9

Blondin, Catherine. "Polysaccharides sulfatés extraits d'algues brunes : activité anticomplémentaire des fucanes." Paris 13, 1992. http://www.theses.fr/1992PA132041.

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Les fucanes sont des polysaccharides sulfatés présents dans la paroi des algues brunes ; majoritairement constitués d'unités -1,2-l-fucose-4-sulfate. Une étude antérieure de leur mécanisme d'action anticoagulante, ainsi que la réalisation de tests in vivo et ex vivo, ont permis d'envisager l'utilisation thérapeutique des fucanes, en tant qu'agent antithrombotique dans la prévention des maladies thromboemboliques. La première partie de notre étude a donc consisté à assurer que le procédé de purification des fucanes, mis en place à l'échelle pilote, était fiable et reproductible. Nous avons pour cela analyse sept lots successifs de fucanes fractionnes, d'un point de vue physicochimique (masse molaire chromatographique, teneurs en fucose, acide uronique, sulfate, oses neutres et protéines), et d'un point de vue biologique (activité anticoagulante). Les résultats nous ont permis de sélectionner un compose de masse molaire apparente 20 000 g/mol, bien défini quant à sa composition chimique et son activité anticoagulante spécifique. Dans un deuxième partie, nous avons examiné l'effet des fucanes sur le système du complément. Le complément est un système protéique complexe qui participe aux défenses immunitaires de l'organisme. Il est composé d'au moins 11 composants dont l'activation en cascade, contrôlée par 9 protéines régulatrices, est à l'origine d'activités biologiques diverses (élimination des bactéries, des virus, opsonisation, participation a la réaction inflammatoire). L'activation anarchique de ces protéines peut survenir dans certaines pathologies (glomérulonéphrites aiguës, lupus érythémateux disséminé) ou être associée à certains traitements (circulation extracorporelle, hémodialyse). L'étude que nous avons effectuée en sérum humain ou en présence de protéines purifiées, a montré que les fucanes possèdent un fort pouvoir inhibiteur de l'activation du complément, de 15 a 90 fois supérieur a celui de l'héparine. Les deux séries de 10 et 13 fractions que nous avons préparées ont été analysées, leur action s'exerce sur les deux voies d'activation du complément et dépend de la masse molaire des fractions. En système semi purifié, les fucanes inhibent la formation de la c3 convertase classique, en empêchant le clivage de la protéine c4 par la sous-unité cls et en inhibant la liaison de la protéine c2 sur le fragment c4b. A même concentration pondérale que l'héparine, ils inhibent la formation des c3 convertases alternes, en inhibant de façon compétitive la liaison de la protéine b sur le fragment c3b. Quand la c3 convertase est stabilisée par la properdine, les fucanes, mieux que l'héparine, catalysent la dissociation des complexes c3bbbp ce qui suggère un effet direct de ces polyanions sur la properdine.
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Siméon, Amandine. "Localisations et rôles des polysaccharides de paroi au cours du développement de deux modèles d’algues brunes : le zygote de Fucus et Ectocarpu." Electronic Thesis or Diss., Sorbonne université, 2018. https://accesdistant.sorbonne-universite.fr/login?url=https://theses-intra.sorbonne-universite.fr/2018SORUS233.pdf.

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La paroi des algues brunes constitue un compartiment cellulaire majeur impliqué dans de nombreuses réponses physiologiques dont la croissance cellulaire, le développement, ou encore dans l’adaptation aux variations physico-chimiques de l’environnement. Tout comme d’autres organismes photosynthétiques (plantes, algues rouges et vertes), les algues brunes ont une paroi essentiellement composée de polysaccharides, mais compte-tenu des distances phylogénétiques, les composés sont distincts, avec nottament des alginates et des fucanes sulfatés. La majorité des connaissances sur ces compositions dérive d’extractions chimiques effectuées sur des algues entières, au cours desquelles l’information cellulaire est perdue. Aujourd’hui, des anticorps monoclonaux spécifiques d’alginates et de fucanes d’algues brunes ont été développés et caractérisés. Ces outils peuvent être utilisés pour localiser précisément à un niveau cellulaire et tissulaire des fractions polysaccharidiques particulières. Outre des informations sur la structure et la composition de la paroi, ces anticorps permettent d’étudier les rôles de ces polysaccharides dans de nombreuses réponses physiologiques, dont le développement. Afin d’étudier ces aspects, deux organismes modèles d’algues brunes, le zygote de Fucus et les sporophytes d’Ectocarpus ont été utilisés. Lors de cette thèse, des glycoprotéines minoritaires, des AGPs (arabino-galactanes protéines) ont été mises en évidence dans la paroi des algues brunes avec des fonctions majeures dans l’embryogénèse chez Fucus. L’utilisation de nos anticorps monoclonaux spécifiques a permis de montrer la dynamique de la mise en place des alginates et des fucanes au cours du développement de nos modèles. J’ai ainsi pu montrer l’implication des fucanes dans la croissance apicale et le rôle crucial du sulfate présent dans l’environnement, dans ce processus
The cell wall of brown algae is a major cell compartment involved in many physiological responses including cell growth, development, or in adaptation to the physico-chemical changes of the environment. Like other photosynthetic organisms (plants, red and green algae), brown algae have a cell wall mainly composed of polysaccharides, but taking into account phylogenetic distances, the compounds are distinct, with notably alginates and sulfated fucans. Most knowledge on cell wall compositions comes from chemical extractions carried out on whole algal plants, with the induced lost of most cellular information. Today, monoclonal antibodies specifically dericted against alginates and sulfated fucans have been developed and characterized. These tools can be used to precisely localize at a cellular and tissue level their particular polysaccharide fractions. In addition to the information on the structure and composition of the cell wall, these antibodies allow to study the biological roles of the cell wall in many functional responses, including during early development. In this study, two model organisms of brown algae, the zygote of Fucus and the sporophytes of Ectocarpus, were used. In term of cell wall composition, glycoproteins known as arabinogalactan proteins (AGPs) have been identified as minor components in the cell walls of brown algae. They were shown to have a functional role in the Fucus embryogenesis. The use of our specific monoclonal antibodies allowed to locate alginates and fucans in cell walls during the development of our models. Notably, I have shown the involvement of sulfated fucans in normal apical growth and the crucial role of sulfate in this process
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Books on the topic "Fucane"

1

Pinelli, Dominique. U Fucone. La Tour d'Aigues: Editions de l'Aube, 1998.

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Catalli, F. Alba Fucens. Roma: Istituto poligrafico e Zecca dello Stato, Libreria dello Stato, 1992.

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Rossetti, Sandro. Le fucine della Valle del Garza. Nave: Comune di Nave, 1996.

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Horwood, Joel. Stoopud fucken animals. London: Nick Hern Books, 2007.

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Scotland), Traverse Theatre (Edinburgh, ed. Stoopud fucken animals. London: Nick Hern Books, 2007.

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Valtergano, Ennio. La fucina del diavolo. Foggia: Bastogi, 2011.

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Il Fucino nella protostoria. Borgo San Lorenzo (FI) [i.e. Florence, Italy]: All'insegna del giglio, 2007.

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Paul. Scritti fucini: (1925-1933). Roma: Studium, 2004.

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Burri, Ezio. Acqua e agricoltura nel Fucino. Roma: Società geografica italiana, 2011.

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1843-1921, Fucini Renato, Barbadori Lande Paola, and Gabinetto scientifico letterario G.P. Vieusseux., eds. I macchiaioli di Renato Fucini. Firenze: Pananti, 1985.

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Book chapters on the topic "Fucane"

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Schomburg, Dietmar, and Dörte Stephan. "Fucose-1-phosphate guanylyltransferase." In Enzyme Handbook, 625–27. Berlin, Heidelberg: Springer Berlin Heidelberg, 1997. http://dx.doi.org/10.1007/978-3-642-59025-2_111.

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Bakker, Hans, Angel Ashikov, Francoise H. Routier, and Rita Gerardy-Schahn. "GDP-Fucose Transporter 1 (SLC35C1)." In Handbook of Glycosyltransferases and Related Genes, 1403–11. Tokyo: Springer Japan, 2014. http://dx.doi.org/10.1007/978-4-431-54240-7_38.

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Renkonen, Risto. "Fucose-1-Phosphate Guanylyltransferase (FPGT)." In Handbook of Glycosyltransferases and Related Genes, 1631–35. Tokyo: Springer Japan, 2014. http://dx.doi.org/10.1007/978-4-431-54240-7_112.

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Pomin, Vitor H. "Structure and Use of Algal Sulfated Fucans and Galactans." In Handbook of Marine Macroalgae, 229–61. Chichester, UK: John Wiley & Sons, Ltd, 2011. http://dx.doi.org/10.1002/9781119977087.ch11.

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Zhang, Rongqing, Liping Xie, and Zhenguang Yan. "Molecular Basis of Biomineralization in Pinctada fucata." In Biomineralization Mechanism of the Pearl Oyster, Pinctada fucata, 1–22. Singapore: Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-13-1459-9_1.

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Zhang, Rongqing, Liping Xie, and Zhenguang Yan. "Identification and Characterization of Biomineralization-Related Genes." In Biomineralization Mechanism of the Pearl Oyster, Pinctada fucata, 23–248. Singapore: Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-13-1459-9_2.

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Zhang, Rongqing, Liping Xie, and Zhenguang Yan. "Identification (Characterization) and Function Studies of Matrix Protein from the Oyster Pinctada fucata." In Biomineralization Mechanism of the Pearl Oyster, Pinctada fucata, 249–443. Singapore: Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-13-1459-9_3.

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Zhang, Rongqing, Liping Xie, and Zhenguang Yan. "The Study on Enzymes Related to Biomineralization of Pinctada fucata." In Biomineralization Mechanism of the Pearl Oyster, Pinctada fucata, 445–507. Singapore: Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-13-1459-9_4.

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Zhang, Rongqing, Liping Xie, and Zhenguang Yan. "Cellular Regulation of Biomineralization in Pinctada fucata." In Biomineralization Mechanism of the Pearl Oyster, Pinctada fucata, 509–73. Singapore: Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-13-1459-9_5.

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Zhang, Rongqing, Liping Xie, and Zhenguang Yan. "Molecular Regulation Mechanism of Biomineralization of Pinctada fucata." In Biomineralization Mechanism of the Pearl Oyster, Pinctada fucata, 575–660. Singapore: Springer Singapore, 2018. http://dx.doi.org/10.1007/978-981-13-1459-9_6.

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Conference papers on the topic "Fucane"

1

Amamiya, Satoshi, Masaaki Izumi, Takanori Matsuzaki, Ryuzo Hasegawa, and Makoto Amamiya. "Fuce." In the 4th international conference. New York, New York, USA: ACM Press, 2007. http://dx.doi.org/10.1145/1242531.1242563.

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Agosta, Fabrizio, Manika Prasad, and Atilla Aydin. "Rock physical properties of carbonate fault rocks, Fucino Basin (central Italy)." In SEG Technical Program Expanded Abstracts 2004. Society of Exploration Geophysicists, 2004. http://dx.doi.org/10.1190/1.1845166.

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Singh, Sudhir, Kuntal Pal, Elliot Ensink, Jessica Yadav, Doron Kletter, Marshall Bern, Anand Mehta, Karsten Melcher, and Brian B. Haab. "Abstract B31: Development of fucose based pancreatic cancer biomarkers using modified lectins." In Abstracts: AACR Special Conference on Pancreatic Cancer: Innovations in Research and Treatment; May 18-21, 2014; New Orleans, LA. American Association for Cancer Research, 2015. http://dx.doi.org/10.1158/1538-7445.panca2014-b31.

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Rani, P. Vimala, Nagarathna Ravi, S. Mercy Shalinie, P. Pariventhan, and K. Rajkumar. "Fuzzy Based Congestion-Aware Secure (FuCaS) Route Selection in ICN." In 2018 9th International Conference on Computing, Communication and Networking Technologies (ICCCNT). IEEE, 2018. http://dx.doi.org/10.1109/icccnt.2018.8494121.

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Frank, E., A. Gallina, M. Baldacci, and M. Miolo. "Cost-benefit analysis of different solutions for sustainable irrigation in Fucino Plain (Italy)." In SUSTAINABLE IRRIGATION 2008. Southampton, UK: WIT Press, 2008. http://dx.doi.org/10.2495/si080261.

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Listinsky, JJ, GP Siegal, and CM Listinsky. "P5-07-04: Is a-L-Fucose Overexpressed on Cells of Aggressive Human Breast Cancers?" In Abstracts: Thirty-Fourth Annual CTRC‐AACR San Antonio Breast Cancer Symposium‐‐ Dec 6‐10, 2011; San Antonio, TX. American Association for Cancer Research, 2011. http://dx.doi.org/10.1158/0008-5472.sabcs11-p5-07-04.

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Kato, Junji, Rishu Takimoto, Takahiro Osuga, Michihiro Ono, Masahiro Hirakawa, Makoto Yoshida, Yasushi Sato, and Fumito Tamura. "Abstract 4463: Targeting SN38 delivery to gastrointestinal cancer cells using a fucose-bound nanoparticle approach." In Proceedings: AACR Annual Meeting 2014; April 5-9, 2014; San Diego, CA. American Association for Cancer Research, 2014. http://dx.doi.org/10.1158/1538-7445.am2014-4463.

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Braster, Rens, Remco Visser, Gestur Vidarsson, and Marjolein van Egmond. "Abstract A02: The art of omission: Low fucose antibodies enhance tumor cell clearance in vivo." In Abstracts: AACR Special Conference: Tumor Immunology and Immunotherapy: A New Chapter; December 1-4, 2014; Orlando, FL. American Association for Cancer Research, 2015. http://dx.doi.org/10.1158/2326-6074.tumimm14-a02.

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Kerr, Sheena C., Stephen D. Carrington, Michaela Wimmerova, Iwona Bucior, Joanne N. Engel, and John V. Fahy. "Inhibiting Fucose Binding Lectins As An Anti-Adhesion And Anti-Infection Strategy For Pseudomonas Airway Infections." In American Thoracic Society 2012 International Conference, May 18-23, 2012 • San Francisco, California. American Thoracic Society, 2012. http://dx.doi.org/10.1164/ajrccm-conference.2012.185.1_meetingabstracts.a2468.

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Takamatsu, J., H. Saito, T. Kamiya, Y. Muranaka, Y. F. Minami, and H. T. Fan. "A NEW MUCOPOLYSACCHARIDE FROM STICHPUS JAPONICUS(SEA CUCUMBER) AND ITS ANTICOAGULANT PRORETIES." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1644185.

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Abstract:
A new mucopolysaccharide(FGAG) has been isolated from the cell wall of Stichopus japonicua. The molecular weight of FGAG is about 50,000. The component sugar of the FGAG are identified as galactosamine, glucuronic acid, fucose and sulfate with the molar ratioof 1:0.94:0.84:3.60,respectively. The anticoagulant effects of FGAG were studied. At low concentration(lμg/ml), FGAG completely inhibited the rabbit plateletaggregation induced by thrombin and prolonged thrombin time of not only human plasma but purified fibrinogen solution to a similar extent, suggesting that action of FGAG is not depend on plasma component(antithrombin III and/or Heparin c.ofactor II).After intravenous injection into rabbits(lmg/kg),significant prolongation of activated partial thromboplastin time(APTT) was observed. Although the in vivo antithrombin activity of the FGAG was weaker than that of heparin.it lasted longer than that of heparin and was not inhibited by platelet factor 4.These results suggested that FGAG is a new and unique mucopolysaccharide with antithrombin activity and may come into use for the treatment ofDiseminated Intravascular Coagulation.
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Reports on the topic "Fucane"

1

Davis, E., R. Currie, and B. Sawyer. Bathymetry, northern Juan De Fuca Ridge. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1987. http://dx.doi.org/10.4095/133932.

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Davis, E., R. Currie, and B. Sawyer. Acoustic imagery, northern Juan de Fuca. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1987. http://dx.doi.org/10.4095/133940.

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Fell, Patrick, and C. H. Seay. Seafloor Positioning Across Juan De Fuca Ridge. Fort Belvoir, VA: Defense Technical Information Center, April 1994. http://dx.doi.org/10.21236/ada285049.

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Malahoff, A., S. F. Hammond, R. W. Embley, R. G. Currie, E E Davis, R. P. Riddihough, and B S Sawyer. Juan de Fuca atlas: preliminary Seabeam bathymetry. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1985. http://dx.doi.org/10.4095/129997.

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Davis, E., R. Currie, and B. Sawyer. Bathymetry, North Central Juan de Fuca ridge. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1987. http://dx.doi.org/10.4095/133934.

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Davis, E., R. Currie, and B. Sawyer. Bathymetry, South Central Juan de Fuca ridge. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1987. http://dx.doi.org/10.4095/133935.

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Malahoff, A., R. G. Currie, E. E. Davis, R. P. Riddihough, and B S Sawyer. Juan de Fuca Ridge atlas: preliminary Seabeam bathymetry. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1985. http://dx.doi.org/10.4095/130002.

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Kilby, C. E. Nearshore Heavy Minerals, northern Juan De Fuca Strait. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1990. http://dx.doi.org/10.4095/131215.

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Davis, E., R. Currie, and B. Sawyer. Acoustic imagery, north central Juan de Fuca ridge. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1987. http://dx.doi.org/10.4095/133942.

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Davis, E., R. Currie, and B. Sawyer. Acoustic imagery, south central Juan de Fuca ridge. Natural Resources Canada/ESS/Scientific and Technical Publishing Services, 1987. http://dx.doi.org/10.4095/133943.

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