Academic literature on the topic 'Cell lignage'
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Journal articles on the topic "Cell lignage"
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Leroi, Armand, Scott Emmons, Ana Cunha, and Ricardo B. R. Azevedo. "The demise of the Platonic worm." Nematology 2, no. 1 (2000): 71–79. http://dx.doi.org/10.1163/156854100508917.
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AbstractNematodes are generally considered to have an adult cell number that does not vary among wildtype individuals as a consequence of invariant cell lineages (eutely). However, there is extensive evidence that at least some cell lineages can be variable in nematodes. In a comparative study of 13 free-living nematode species, we have shown that the adult epidermis of most species contained variable numbers of nuclei and that this variance was positively correlated with mean epidermal nuclear number. Here we present simulations of the lateral seam cell lineages of four species and show that variance in cell number is influenced by lineage topology, as well as by the frequency of lineage variants. We show that the epidermal variability of Panagrellus redivivus cannot be accounted for by the complexity of its lineage, but requires higher levels of lineage variability than are found in Caenorhabditis elegans, Oscheius myriophila and Rhabditella octopleura. Our findings suggest that many nematodes may have tissues composed of indeterminate numbers of cells formed from variable lineages and, as such, resemble other metazoans. Les nématodes sont généralement considérés comme ayant un nombre de cellules invariable chez les individus de type sauvage, conséquence d’un lignage cellulaire fixe (eutélie). Cependant, il est d’évidence qu’au moins certains des lignages cellulaires peuvent varier chez les nématodes. Dans une étude comparative portant sur 13 espèces de nématodes libres, nous avions montré que l’épiderme de la plupart de ces espèces comportait un nombre variable de noyaux et que cette variabilité était corrélée positivement avec le nombre de noyaux épidermiques. Nous présentons ici des simulations des lignages cellulaires de la suture latérale de quatre espèces et démontrons que le nombre de cellules est influencé tant par la topologie du lignage que par la fréquence des variants de ce lignage. Nous montrons que la variabilité de l’épiderme de Panagrellus redivivus ne peut être mise au compte de la complexité de son lignage, mais demande des niveaux élevés de variabilité de ce lignage, tels ceux trouvés chez Caenorhabditis elegans, Oscheius myriophila et Rhabditella octopleura. Nos observations suggèrent que nombre de nématodes possèdent des tissus composés d’un nombre indéterminé de cellules dérivant de lignages variables et, de ce fait, ressemblent aux autres metazoaires.
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Monties, Bernard. "Composition chimique des bois de chêne: composés phénoliques, relations avec quelques propriétés physiques et chimiques susceptibles d'influencer la qualité des vins et des eaux-de-vie." OENO One 21, no. 3 (1987): 169. http://dx.doi.org/10.20870/oeno-one.1987.21.3.1282.
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<p style="text-align: justify;">Les polyphénols du bois de chêne, extractibles et composés liés à la paroi végétale = lignines, lignanes, tanins et aldéhydes phénoliques, ont été envisagés au niveau moléculaire de leurs relations avec les propriétés physico-chimiques des bois : retrait, porosité, propriétés mécaniques.</p><p style="text-align: justify;">Des résultats originaux ont été aussi présentés concernant le fractionnement des polyphénols pariétaux, l'incrustation des parois par les tanins hydrolysables: acide ellagique associé à des fractions de lignine, ainsi que la formation d'aldéhydes phénoliques (vanilline, syringaldéhyde, aldéhydes coniférylique et sinapylique) par pyrolyse douce de la lignine. Des mécanismes réactionnels hypothétiques ont été suggérés.</p><p style="text-align: justify;">+++</p><p style="text-align: justify;">Oak wood phenolics, extractives and cell wall linked compounds : lignins, lignans, tanins and phenolic aldehydes have been discussed, at the molecular level, in their relations with physico-chemical properties of wood = shrinking, permeability and mechanical properties.</p><p style="text-align: justify;">Unpublished results have been also reported concerning fractionnation of cell wall phenolics, incrustation of cell wall by tanins: ellagic acid associated with lignins fractions and formation of phenolic aldehydes (vanillin, syringaldehyde, coniferaldehyde, sinapaldehyde) during mild pyrolysis of lignin in oak wood. Hypotherical reaction mechanism have been suggested.</p>
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Huh, Jungmoo, Chang-Min Lee, Seoyoung Lee, Soeun Kim, Namki Cho, and Young-Chang Cho. "Comprehensive Characterization of Lignans from Forsythia viridissima by UHPLC-ESI-QTOF-MS, and Their NO Inhibitory Effects on RAW 264.7 Cells." Molecules 24, no. 14 (2019): 2649. http://dx.doi.org/10.3390/molecules24142649.
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Lignans are known to be an important class of phenylpropanoid secondary metabolites. In the course of our studies on the chemodiversity of lignans, the necessity arose to develop a method for the fast detection and identification of bioactive lignan subclasses. In this study, we detected 10 lignan derivatives of different extracts of F. viridissima by UHPLC-ESI-QTOF-MS. Lignan glycosides (1 and 2), lignans (3 and 4), and lignan dimers (5–10) were identified by analysis of their exact masses and MSe spectra along with the characteristic mass fragmentation patterns and molecular formulas. We further investigated NO inhibitory effects of F. viridissima fractions and their major lignan derivatives to evaluate those anti-inflammatory effects. The methylene chloride fraction of F. viridissima as well as compounds 8 and 10 showed potent dose-dependent NO inhibitory effects on RAW 264.7 cells. Corresponding to the NO inhibition by compounds 8 and 10, lipopolysaccharide (LPS)-induced inducible nitric oxide synthase (iNOS) expression was notably reduced by both compounds. Our combined data with the bioactive results and the component analysis by UHPLC-ESI-QTOF-MS suggest that the methylene chloride fraction of F. viridissima roots could be potential anti-inflammatory agents and these are related to major lignans including dimeric dibenzylbutyrolactone lignans.
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Mulabagala, Vanisree, Gottumukkala V. Subbaraju, Modukuri V. Ramani, David L. DeWitt, and Muraleedharan G. Nair. "Lipid Peroxidation, Cyclooxygenase Enzyme and Tumor Cell Proliferation Inhibitory Lignans from Justicia Species." Natural Product Communications 3, no. 11 (2008): 1934578X0800301. http://dx.doi.org/10.1177/1934578x0800301109.
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The genus Justicia is a rich source of lignans, especially aryl naphthalide lignans. Lignans are biologically active phytochemicals, and are reported to possess antiplatelet, antiviral, anti-tumor, antidepressant, and insect antifeedant activities. In the present study, we report lipid peroxidation (LPO), cyclooxygenase (COX-1 and −2) enzyme and tumor cell proliferation inhibitory activities of lignans, namely, lariciresinol (1), isolariciresinol (2), neesiinoside A (3), justirumalin (4), justalakonin (5), justicidin G (6), sesamin (7), sesamolin (8), jusmicranthin methyl ether (9), taiwanin E methyl ether (10), lignan J1 (11), jusneesiinol (12), jusmicranthin ethyl ether (13), tiruneesiin (14), justicidin E (15) and simplexolin (16). Lignans 1 and 2 were isolated from J. tranquebariensis, 3, 4, 6, 9, 10, 11, 12, 13 and 14 from J. neesii Ramamoorthy, 5 from J. purpurea and 7, 8, 15 and 16 from J. orbiculata. Among the lignans assayed, 1, 2, 12 and 14 showed 79.6, 86.2, 90.8 and 95.9% and 3 41.3% inhibition of LPO at 25 μg/mL. The lignans 4, 9 and 16 inhibited COX-2 enzyme by 67.2, 73.0 and 72.8%, respectively, when tested at 25 μg/mL. Similarly, lignans 3, 4, 10, 11 and 15 inhibited COX-1 enzyme by 59.9, 89.2, 69.6, 73.9, and 80.1%, respectively, at 25 μg/mL. When assayed at 25 μg/mL, 4 inhibited human stomach and breast cancer cell lines by 42.8 and 42.1%, respectively. Also, at 25 μg/mL the lignan 7 inhibited the growth of CNS, lung and breast cancer cell lines by 50.0, 41.3, and 42.0 %, respectively, and 15 inhibited the proliferation of lung, breast and colon cell lines by 40–53%.
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Mansikkala, Tuomas, Minna Patanen, Anna Kärkönen, et al. "Lignans in Knotwood of Norway Spruce: Localisation with Soft X-ray Microscopy and Scanning Transmission Electron Microscopy with Energy Dispersive X-ray Spectroscopy." Molecules 25, no. 13 (2020): 2997. http://dx.doi.org/10.3390/molecules25132997.
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Lignans are bioactive compounds that are especially abundant in the Norway spruce (Picea abies L. Karst.) knotwood. By combining a variety of chromatographic, spectroscopic and imaging techniques, we were able to quantify, qualify and localise the easily extractable lignans in the xylem tissue. The knotwood samples contained 15 different lignans according to the gas chromatography-mass spectrometry analysis. They comprised 16% of the knotwood dry weight and 82% of the acetone extract. The main lignans were found to be hydroxymatairesinols HMR1 and HMR2. Cryosectioned and resin-embedded ultrathin sections of the knotwood were analysed with scanning transmission X-ray microscopy (STXM). Cryosectioning was found to retain only lignan residues inside the cell lumina. In the resin-embedded samples, lignan was interpreted to be unevenly distributed inside the cell lumina, and partially confined in deposits which were either readily present in the lumina or formed when OsO4 used in staining reacted with the lignans. Furthermore, the multi-technique characterisation enabled us to obtain information on the chemical composition of the structural components of knotwood. A simple spectral analysis of the STXM data gave consistent results with the gas chromatographic methods about the relative amounts of cell wall components (lignin and polysaccharides). The STXM analysis also indicated that a torus of a bordered pit contained aromatic compounds, possibly lignin.
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Mason, Julie K., and Lilian U. Thompson. "Flaxseed and its lignan and oil components: can they play a role in reducing the risk of and improving the treatment of breast cancer?" Applied Physiology, Nutrition, and Metabolism 39, no. 6 (2014): 663–78. http://dx.doi.org/10.1139/apnm-2013-0420.
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Flaxseed (FS), rich in the phytoestrogen lignans and α-linolenic acid-rich oil, has been suggested to have an anticancer effect. Questions remain whether FS and its lignan and oil components are effective in reducing breast cancer risk and tumour growth, and can interact beneficially with breast cancer drugs. To find answers, in vitro, animal, observational, and clinical studies on FS and its lignan and oil components were reviewed. The majority of studies in various rodent models show that 2.5%–10% FS diet or the equivalent amount of lignan or oil reduces tumour growth. Ten percent FS and equivalent lignans do not interfere with but rather increase the effectiveness of tamoxifen (80 mg/day) while the 4% FS oil increases trastuzumab/Herceptin (2.5 mg/kg) effectiveness. Observational studies show that FS and lignan intake, urinary excretion, or serum levels are associated with reduced risk, particularly in postmenopausal women. Lignans reduce breast cancer and all-cause mortality by 33%–70% and 40%–53%, respectively, without reducing tamoxifen effectiveness. Clinical trials show that FS (25 g/day with 50 mg lignans; 32 days) reduces tumour growth in breast cancer patients and lignans (50 mg/day; 1 year) reduces risk in premenopausal women. Mechanisms include decreased cell proliferation and angiogenesis and increased apoptosis through modulation of estrogen metabolism and estrogen receptor and growth factor receptor signalling pathways. More clinical trials are needed but current overall evidence indicates that FS and its components are effective in the risk reduction and treatment of breast cancer and safe for consumption by breast cancer patients.
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Xu, Xuan, Cédric Guignard, Jenny Renaut, et al. "Insights into Lignan Composition and Biosynthesis in Stinging Nettle (Urtica dioica L.)." Molecules 24, no. 21 (2019): 3863. http://dx.doi.org/10.3390/molecules24213863.
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Stinging nettle (Urtica dioica L.) has been used as herbal medicine to treat various ailments since ancient times. The biological activity of nettle is chiefly attributed to a large group of phenylpropanoid dimers, namely lignans. Despite the pharmacological importance of nettle lignans, there are no studies addressing lignan biosynthesis in this plant. We herein identified 14 genes encoding dirigent proteins (UdDIRs) and 3 pinoresinol-lariciresinol reductase genes (UdPLRs) in nettle, which are two gene families known to be associated with lignan biosynthesis. Expression profiling of these genes on different organs/tissues revealed a specific expression pattern. Particularly, UdDIR7, 12 and 13 displayed a remarkable high expression in the top internode, fibre tissues of bottom internodes and roots, respectively. The relatively high expression of UdPLR1 and UdPLR2 in the young internodes, core tissue of bottom internode and roots is consistent with the high accumulation of lariciresinol and secoisolariciresinol in these tissues. Lignan quantification showed a high abundance of pinoresinol in roots and pinoresinol diglucosides in young internodes and leaves. This study sheds light on lignan composition and biosynthesis in nettle, providing a good basis for further functional analysis of DIRs and PLRs and, ultimately, engineering lignan metabolism in planta and in cell cultures.
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Bylund, Annika, Niina Saarinen, Jie-xian Zhang, et al. "Anticancer Effects of a Plant Lignan 7-Hydroxymatairesinol on a Prostate Cancer Model In Vivo." Experimental Biology and Medicine 230, no. 3 (2005): 217–23. http://dx.doi.org/10.1177/153537020523000308.
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Clinical intervention studies and experimental studies with lignan-rich diets suggest that lignans may have inhibitory effects on prostate cancer, but no clinical or experimental studies with purified lignans have been published. The purpose of this study was to investigate the effect of a plant lignan 7-hydroxymatairesinol (HMR) on LNCaP human prostate cancer xenografts in athymic mice. Athymic nude male mice were injected subcutaneously with LNCaP cells. Starting 3 days after tumor cell injections, a control diet or a control diet supplemented with 0.15% or 0.30% of HMR was administered to mice and the tumor take rate and growth was observed for 9 weeks. HMR diet inhibited the growth of LNCaP tumors. Mice treated with HMR had smaller tumor volume, lower tumor take rate, increased proportion of nongrowing tumors, and higher tumor cell apoptotic index compared with controls. Furthermore, the cell proliferation index was reduced in mice receiving the 0.30% HMR diet compared with mice receiving the control diet. Our results suggest that dietary HMR started at the early phase of the tumor development inhibits the growth of the LNCaP human prostate cancer xenografts in athymic male mice.
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Aimaiti, Simayijiang, Yohei Saito, Shuichi Fukuyoshi, et al. "Isolation, Structure Elucidation, and Antiproliferative Activity of Butanolides and Lignan Glycosides from the Fruit of Hernandia nymphaeifolia." Molecules 24, no. 21 (2019): 4005. http://dx.doi.org/10.3390/molecules24214005.
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Seven new butanolides, peltanolides A–G (1–7), and two lignan glucosides, peltasides A (8) and B (9), along with eleven known compounds, 10–20, were isolated from a crude CH3OH/CH2Cl2 (1:1) extract of the fruit of Hernandia nymphaeifolia (Hernandiaceae). The structures of 1–9 were characterized by extensive 1D and 2D NMR spectroscopic and HRMS analysis. The absolute configurations of newly isolated compounds 1–9 were determined from data obtained by optical rotation and electronic circular dichroism (ECD) exciton chirality methods. Butanolides and lignan glucosides have not been isolated previously from this genus. Several isolated compounds were evaluated for antiproliferative activity against human tumor cell lines. Lignans 15 and 16 were slightly active against chemosensitive tumor cell lines A549 and MCF-7, respectively. Furthermore, both compounds displayed significant activity (IC50 = 5 µM) against a P-glycoprotein overexpressing multidrug-resistant tumor cell line (KB-VIN) but were less active against its parent chemosensitive cell line (KB).
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Basini, Giuseppina, Carmela Spatafora, Corrado Tringali, Simona Bussolati, and Francesca Grasselli. "Effects of a Ferulate-Derived Dihydrobenzofuran Neolignan on Angiogenesis, Steroidogenesis, and Redox Status in a Swine Cell Model." Journal of Biomolecular Screening 19, no. 9 (2014): 1282–89. http://dx.doi.org/10.1177/1087057114536226.
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In the ongoing search for new therapeutic compounds, lignans and neolignans, which are widely distributed in plants, deserve special attention because of their interactions with several biological targets. Searching for potential antiangiogenic agents related to natural lignans/neolignans, we were attracted by a previously studied synthetic dihydrobenzofuran neolignan. We synthesized the compound by means of an eco-friendly, enzyme-mediated biomimetic coupling of the methyl ester of ferulic acid, and the present study was aimed to deeply investigate its effect in angiogenesis bioassays validated in our laboratory. In addition, a previously well-defined granulosa cell model was employed to evaluate the effect of dihydrobenzofuran neolignan on cell viability, steroidogenesis, and redox status. Present data support the antiangiogenic effect of this neolignan. Moreover, we demonstrate that, at least at the highest concentrations tested, dihydrobenzofuran neolignan affects granulosa cell viability and steroidogenesis. In addition, the compound inhibits generation of free radicals and stimulates scavenger enzyme activities. The present data, which are a further deepening of the evaluation of the biological activities of the dihydrobenzofuran lignan in well-defined cell models, are of interest and worthy of special attention.
Dissertations / Theses on the topic "Cell lignage"
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Finot, Laurence. "Identification et caractérisation du lignage épithélial dans la glande mammaire bovine." Thesis, Rennes, Agrocampus Ouest, 2019. http://www.theses.fr/2019NSARB319/document.
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Le développement de l’épithélium mammaire dépend des cellules souches qui, en proliférant et se différenciant, donnent naissance aux cellules du lignage épithélial. Les cellules souches sont ensuite sollicitées à chaque gestation pour régénérer une partie de l’épithélium. L’objectif de cette thèse est d’identifier et de caractériser en profondeur les différents types de cellules du lignage épithélial mammaire bovin par des approches de cytométrie en flux et de tri cellulaire. Nous avons défini et étudié des (sous)populations épithéliales engagées dans le développement mammaire à la puberté. A ce stade, l’épithélium mammaire contient de rares cellules souches mammaires, des cellules progénitrices à typage mixte luminal/basal et des cellules luminales et basales. Ces (sous)populations diffèrent soit en proportion soit en caractéristiques, voire les deux, aux stades physiologiques majeurssuivants (lactation et tarissement). Les cellules basales diminuent en lactation et au tarissement. Elles possèdent une signature moléculaire propre à chaque stade. La population luminale, composée de plusieurs sous-populations, est la plus variable. Elle arbore une réceptivité hormonale différente à chaque stade. Des (sous)populations épithéliales n’apparaissent qu’à un stade précis (puberté ou lactation) et disparaissent aux autres, comme certaines cellules prolifératives définies comme cellules progénitrices. Enfin, la fraction de rares cellules souches putatives diminue graduellement, de la puberté aux stades suivants, tout en conservant des caractéristiques moléculaires similaires. Ces<br>The development of the mammary epithelium relies on the mammary stem cells which, by proliferating and differentiating, give rise to the luminal, basal and progenitor cells of the epithelial lineage. The stem cells are then solicited at each gestation to regenerate a part of the epithelium. In this thesis work, we aim at identifying and characterizing in depth the different types of cell constitutive of the bovine mammary epithelial cell lineage by flow cytometry and cell sorting approaches. We defined and studied epithelial (sub)populations committed to mammary development at puberty. At this stage, the mammary epithelium contains rare mammary stem cells, mixed luminal/ basal progenitors, as well as luminal and basal cells.These (sub)populations were found to differ in proportion and/or characteristics at thesubsequent major physiological stages (lactation and dry periods). Basal cells decrease at lactation and dry off. They harbor a specific molecular signature at each stage. The luminal population, composed of several subpopulations, is the most variable. The hormonal receptivity of these cells changes at each physiological stage. Interestingly, some epithelial populations only appear at specific stages (puberty or lactation) and disappear at others, as one subpopulation of proliferative cells that we defined as progenitor cells. At last, the pool of rare putative stem cells gradually decreases from puberty to the next stages while maintaining a similar molecular signature. These are novel insights that show that the epithelial lineage evolves substantially through the
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Fabrèges, Dimitri. "Phenotypic Variations In Animal Morphogenesis : Sea Urchin Twins And Cloned Rabbits." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLS010/document.
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La variabilité est une propriété intrinsèque aux systèmes biologiques, essentielle pour l'évolution et l'embryogénèse. Souvent considérée comme du bruit, ce n'est que récemment que l'aléatoire des processus biologiques a commencé à être systématiquement étudié. Cette thèse pose les questions suivantes : qu'est-ce qu'un développement normal ? Quel est l'étendue et le rôle de la variabilité dans la robustesse et la résilience du développement embryonnaire ?Ces questions sont posées pour le lapin (Oryctolagus cuniculus) et l'oursin (Paracentrotus lividus et Sphaerechinus granularis).Nous nous sommes aussi intéressé à la quantification du déterminisme de la variabilité embryonnaire à l'aide d'oursins jumeaux et de lapins clonés.La mesure des comportements cellulaires est effectuée sur des lignages cellulaires obtenus à partir d'imagerie 3D+temps. Nous montrons que les oursins jumeaux peuvent se développer selon trois phénotypes différents, jamais observés chez le normal, avant de converger vers une blastula d'apparence normale. De plus, les comparaisons entre et au sein des pairs de jumeaux montrent que le phénotype et la survie ne dépend que de l'histoire individuelle des embryos.Nos mesures quantitatives des pairs de jumeaux amènent des questions ouvrant de nouveaux horizons de recherche : les jumeaux sont-ils robustes ou résilient ?Le développement pré-implantatoire des lapins a été étudié sur cinq embryons numériques (trois sauvages et deux clones), du stade 32-cellules à l'éclosion.Nous montrons que les divisions asymétriques internes et externes régulent la variation du nombre de cellules internes ainsi que la taille de la masse cellulaire.De plus, la variation du nombre de cellules internes est plus grande que pour les cellules externes, ce qui semble directement lié au taux de morts cellulaires.Notre hypothèse est que le potentiel de bon développement des clones est assuré par une grande plasticité épigénétique des cellules donneuses.Ce travail espère définir des méthodes et des concepts fondateurs pour une exploration quantitative et une modélisation multi-échelle de la morphogénèse animale<br>Variability is an intrinsic characteristic of biological systems, essential for evolution and embryogenesis.Considered as noise for centuries, it is only recently that the stochasticity of biological processes has began to be systematically explored.The present thesis addresses the following questions: What is a normal development?What is the extent and role of variability in developmental robustness and resilience?We tackle these issues in rabbit (Oryctolagus cuniculus) and sea urchin (Paracentrotus lividus and Sphaerechinus granularis).We also aimed to quantify determinism and stochasticity of developmental variability by means of sea urchin twins and cloned rabbits.Variations in cell behaviors were investigated through reconstruction of cell lineage from 3D+time imaging.We showed that sea urchin twins can follow three different developmental paths never observed in normal embryo, before converging to normal looking blastula.Moreover, comparisons between and within pairs of twins revealed that phenotype and survival depend on individual history alone.Our quantitative observation of twin pairs raises question opening a future line of research: are twins robust or resilient?Rabbit preimplantation development was explored with five digital specimens (three wild-types and two clones) from the 32-cell stage to hatching.We showed that inner and outer asymmetric divisions regulate the variation of inner cell number and may control inner cell mass size.In addition, the variation of inner cell number in clones is higher than outer cells which seems to be directly correlated to their cell death ratio.Our current hypothesis is that the potential to lead to viable clones requires plasticity of donor's epigenetic state.This work is expected to ground concepts and methods for a quantitative exploration and further multilevel modeling of morphogenetic processes
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Yeo, Wendy Wai Yeng. "Differentiation of skeletal muscle-derived stem cells into beta pancreatic lineage." Thesis, Montpellier, 2015. http://www.theses.fr/2015MONTS091.
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Le diabète de type 1 (DT1) est caractérisé par des niveaux élevés de glucose en raison de la destruction des cellules ß pancréatiques sécrétrices d'insuline. Cependant, les thérapies actuelles de remplacement des cellules bêta du pancréas impliquant la transplantation d'îlots pancréatiques sont techniquement difficiles et limitées par la disponibilité de don d'organes. Bien que les cellules souches embryonnaires et les cellules souches pluripotentes induites soient intensément étudiées, aucune de ces deux sources de cellules souches ne peut être utilisée directement sans le risque de développement de tumeurs. Les cellules souches dérivées du muscle squelettique (MDSC) sont une source de cellules alternative intéressante car elles sont multi-potentes et peuvent donc se différencier vers plusieurs lignages cellulaires tels que des cellules cardiaques à battement autonome “pacemaker-like” et des cellules neuronales. Par conséquent, nous avons émis l'hypothèse qu'elles pourraient se différencier en lignées de type pancréatique. Les objectifs de cette étude étaient donc d'étudier le potentiel des MDSC (1) à se différencier in vitro en cellules beta pancréatiques exprimant l'insuline et (2) à se différentier in vivo dans le pancréas et ainsi réduire l'hyperglycémie chez la souris modèle d'un diabète de type 1. Dans cette étude, les MDSC de muscle de souris ont été isolées via une série de passages des cellules les moins adhérentes en culture. Les cellules souches ainsi isolées peuvent adhérer sur une couche de cellules de types fibroblastes ou sur une matrice extra-cellulaire de type laminine pour ensuite se différentier in vitro ou bien être utilisées comme cellules souches MDSC non-adhérentes et non différentiées pour les études in vivo. In vitro, les MDSC peuvent se différencier spontanément en agrégats de cellules formant des îlots et exprimant des marqueurs de cellules bêta identifiés par immunofluorescence et analyse “PCR transcription inverse”. Ceci a été confirmé par immuno-analyse montrant l'expression des protéines nécessaires à la fonction des cellules ß, comme Nkx6.1, MafA et Glut2. Les MDSC différenciées en aggrégats cellulaires de type îlots pancréatiques montrent une sécrétion d'insuline en réponse au glucose in vitro. Cependant, dans des modèles murins de DT1 induit par la streptozotocine, l'injection intra-péritonéale des MDSC n'a pas permis de rétablir chez les souris diabétiques une normoglycémie du glucose sanguin en dépit d'un engreffement des MDSC dans les tissus pancréatiques. Ces données montrent que les MDSC peuvent constituer une source de cellules souches alternative intéressante pour le traitement du diabète<br>Type 1 Diabetes (T1D) is characterized by high and poorly controlled glucose levels due to the destruction of insulin-secreting pancreatic ß-cells. However, current ß-cell replacement therapies, involving pancreas and pancreatic islet transplantation are technically demanding and limited by donor availability. While embryonic stem cells and induced pluripotent stem cells are intensely investigated, neither can be used due to safety issues. Skeletal muscle-derived stem cells (MDSC) are an attractive alternative cell source as they have the potential to undergo multilineage differentiation into beating pacemaker-like cells and neuronal cells. Hence, it is hypothesised that they can differentiate into pancreatic lineages. This led to the goals of this study, which were (1) to investigate the potential of MDSC to differentiate into mature insulin expressing cells in vitro and (2) to reduce hyperglycemia in mouse model type 1 diabetes. In this study, MDSC were isolated from mouse via a serial pre-plating based on the adhesive characteristics of cultured cells, in which the cells of interest adhered to plates at a later time for in vitro differentiation, while the non-adherence undifferentiated MDSC were used for in vivo study. The MDSC were found to spontaneously differentiate into islet-like aggregates and expressed ß-cell markers in vitro, as determined by immunofluorescence and reverse transcription PCR analyses. This was further confirmed by immunoblotting analysis showing expression of proteins required for ß-cell function, such as Nkx6.1, MafA and Glut2. The differentiation of MDSC into islet-like clusters demonstrated glucose responsiveness in vitro. In streptozotocin-induced T1D mouse models, intraperitoneal injection of the undifferentiated MDSC did not restore the blood glucose levels of the diabetic mice to normoglycemia despite successful engraftment of MDSC into the pancreatic tissues. Taken together, these data show that MDSC may serve as an alternative source of stem cells for the treatment of diabetes
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Fernique, Pierre. "A statistical modeling framework for analyzing tree-indexed data : application to plant development on microscopic and macroscopic scales." Thesis, Montpellier 2, 2014. http://www.theses.fr/2014MON20064/document.
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Nous nous intéressons à des modèles statistiques pour les données indexées par des arborescences. Dans le contexte de l'équipe Virtual Plants, équipe hôte de cette thèse, les applications d'intérêt portent sur le développement de la plante et sa modulation par des facteurs environnementaux et génétiques. Nous nous restreignons donc à des applications issues du développement de la plante, à la fois au niveau microscopique avec l'étude de la lignée cellulaire du tissu biologique servant à la croissance des plantes, et au niveau macroscopique avec le mécanisme de production de branches. Le catalogue de modèles disponibles pour les données indexées par des arborescences est beaucoup moins important que celui disponible pour les données indexées par des chemins. Cette thèse vise donc à proposer un cadre de modélisation statistique pour l'étude de patterns pour données indexées par des arborescences. À cette fin, deux classes différentes de modèles statistiques, les modèles de Markov et de détection de ruptures, sont étudiées<br>We address statistical models for tree-indexed data.Tree-indexed data can be seen as a generalization of path-indexed data since directed path graphs are directed tree graphs where there is at most one child per vertex.In the context of the Virtual Plants team, host team of this thesis, applications of interest focus on plant development and its modulation by environmental and genetic factors.We thus focus on plant developmental applications, both at the microscopic level with the study of the cell lineage in the biological tissue responsible for the plant growth, and at the macroscopic level with the mechanism of production of branches. The catalog of models available for tree-indexed data is far less important than the one available for path-indexed data.This thesis therefore aims at proposing a statistical modeling framework for studying patterns in tree-indexed data.To this end, two different classes of statistical models, Markov and change-point models, are investigated
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Villoutreix, Paul. "Aléatoire et variabilité dans l’embryogenèse animale, une approche multi-échelle." Thesis, Sorbonne Paris Cité, 2015. http://www.theses.fr/2015PA05T016/document.
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Nous proposons dans cette thèse de caractériser quantitativement la variabilité à différentes échelles au cours de l'embryogenèse. Pour ce faire, nous utilisons une combinaison de modèles mathématiques et de résultats expérimentaux. Dans la première partie, nous utilisons une petite cohorte d'oursins digitaux pour construire une représentation prototypique du lignage cellulaire, reliant les caractéristiques des cellules individuelles avec les dynamiques à l'échelle de l'embryon tout entier. Ce modèle probabiliste multi-niveau et empirique repose sur les symétries des embryons et sur les identités cellulaires; cela permet d'identifier un niveau de granularité générique pour observer les distributions de caractéristiques cellulaires individuelles. Le prototype est défini comme le barycentre de la cohorte dans la variété statistique correspondante. Parmi plusieurs résultats, nous montrons que la variabilité intra-individuelle est impliquée dans la reproductibilité du développement embryonnaire. Dans la seconde partie, nous considérons les mécanismes sources de variabilité au cours du développement et leurs relations à l'évolution. En nous appuyant sur des résultats expérimentaux montrant une pénétrance incomplète et une expressivité variable de phénotype dans une lignée mutante du poisson zèbre, nous proposons une clarification des différents niveaux de variabilité biologique reposant sur une analogie formelle avec le cadre mathématique de la mécanique quantique. Nous trouvons notamment une analogie formelle entre l'intrication quantique et le schéma Mendélien de transmission héréditaire. Dans la troisième partie, nous étudions l'organisation biologique et ses relations aux trajectoires développementales. En adaptant les outils de la topologie algébrique, nous caractérisons des invariants du réseaux de contacts cellulaires extrait d'images de microscopie confocale d'épithéliums de différentes espèces et de différents fonds génétiques. En particulier, nous montrons l'influence des histoires individuelles sur la distribution spatiales des cellules dans un tissu épithélial<br>We propose in this thesis to characterize variability quantitatively at various scales during embryogenesis. We use a combination of mathematical models and experimental results. In the first part, we use a small cohort of digital sea urchin embryos to construct a prototypical representation of the cell lineage, which relates individual cell features with embryo-level dynamics. This multi-level data-driven probabilistic model relies on symmetries of the embryo and known cell types, which provide a generic coarse-grained level of observation for distributions of individual cell features. The prototype is defined as the centroid of the cohort in the corresponding statistical manifold. Among several results, we show that intra-individual variability is involved in the reproducibility of the developmental process. In the second part, we consider the mechanisms sources of variability during development and their relations to evolution. Building on experimental results showing variable phenotypic expression and incomplete penetrance in a zebrafish mutant line, we propose a clarification of the various levels of biological variability using a formal analogy with quantum mechanics mathematical framework. Surprisingly, we find a formal analogy between quantum entanglement and Mendel’s idealized scheme of inheritance. In the third part, we study biological organization and its relations to developmental paths. By adapting the tools of algebraic topology, we compute invariants of the network of cellular contacts extracted from confocal microscopy images of epithelia from different species and genetic backgrounds. In particular, we show the influence of individual histories on the spatial distribution of cells in epithelial tissues
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Uden, Wilhelmus van. "The production of podophyllotoxin and related cytotoxic lignans by plant cell cultures." [S.l. : [Groningen : s.n.] ; University Library Groningen] [Host], 1992. http://irs.ub.rug.nl/ppn/293040230.
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Allen, Kristi Lynne. "Therapeutic reactivation of the p53 tumor suppressor protein in HPV-positive cervical cancer cells by the creosote bush lignan 3'-O-methyl-nordihydroguaiaretic acid." [Kent, Ohio] : Kent State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=kent1176432164.
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Thesis (Ph.D.)--Kent State University, 2007.<br>Title from PDF t.p. (viewed Mar. 11, 2009). Advisor: Angelo L. DeLucia. Keywords: human papillomavirus, E6 oncogene, lignan, p53, apoptosis. Includes bibliographical references (p. 132-144).
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Daclin, Marie. "Mécanismes de développement des cellules épendymaires : origine et lignage des cellules épendymaires dans le cerveau des mammifères." Thesis, Paris Sciences et Lettres (ComUE), 2018. http://www.theses.fr/2018PSLEE015.
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Les cellules épendymaires sont des cellules multiciliées qui tapissent les parois de toutes les cavités du cerveau. Une fois différenciées, ces cellules ne se divisent plus au cours de la vie. Le battement de ces multiples cils motiles joue un rôle important pour maintenir un flux constant de liquide cérébrospinal à travers toutes les cavités cérébrales. Les cellules épendymaires assurent également des fonctions critiques d’échanges moléculaires avec le liquide cérébrospinal. Dans son ensemble, l’implication des cellules épendymaires et de leurs cils motiles s’avère d’une importance majeure dans le maintien des circuits neuraux ainsi que dans le fonctionnement plus global du cerveau. Récemment, une nouvelle caractéristique des cellules épendymaires a été identifiée ; elles font partie d’un microenvironnement appelé une « niche » centrée autour de cellules souches neurales dans le cerveau du rongeur adulte. Ces cellules souches neurales adultes sont capables de produire de nouveaux neurones qui migreront vers le bulbe olfactif des rongeurs adultes. Concernant leur origine, il a été montré que les cellules épendymaires multiciliées dérivent des cellules souches neurales durant les stades tardifs embryonnaires. Ces mêmes cellules souches peuvent d’ailleurs donner naissance à la plupart des différents types de cellules du cerveau. Cependant, les mécanismes par lesquels les cellules souches décident de leur destin cellulaire restent largement méconnus. Dans ce projet, nous étudions quel type de division donne naissance à des cellules épendymaires et nous nous intéressons également au lignage épendymaire. Nos données suggèrent que les cellules épendymaires ne migrent pas après leur dernière division et qu’elles restent à proximité de l’endroit où elles ont été produites. Chose particulièrement intéressante, nous montrons que les cellules épendymaires peuvent être générées par division symétrique ou asymétrique. Nos résultats révèlent aussi que les cellules souches neurales embryonnaires se divisent de manière asymétrique pour donner naissance à la fois à une celluleépendymaire et à une cellule souche neurale adulte. Ces données viennent s’ajouter à la connaissance actuelle que nous avons du développement du cerveau. De plus, elles pourraient contribuer à ouvrir de nouvelles perspectives et stratégies thérapeutiques pour soigner les maladies neurodégénératives à beaucoup plus long terme<br>Ependymal cells are multiciliated cells lining the walls of all brain cavities. Once they are mature, they do not divide during life. Their motile ciliary beating endorses a crucial role in maintaining a proper flow of cerebrospinal fluid throughout all brain cavities. Ependymal cells also ensure critical molecular exchanges of the cerebrospinal fluid. On the whole, the involvement of ependymal cells and their multiple motile cilia in the maintenance of the neural circuits and more globally in the well-functioning of the entire brain have proven paramount. More recently, a new characteristic of ependymal cells has been brought to light. Namely, they are part of a microenvironment so called a “niche” surrounding adult neural stem cells in the adult rodent brain. Noteworthy, these adult neuralstem cells are capable of producing new neurons that will migrate to the olfactory bulb of rodents. In terms of their origin, it was shown that multiciliated ependymal cells derive from neural stem cells during late embryonic stages. Besides, the same stem cells can give rise to most cell types of the brain. However, little is known about how fate-decision is made in neural stem cells. In this project, we tackle more particularly how multiciliated ependymal cells arise from the neural stem cells. Most specifically, we address the type of celldivision and the ependymal cell lineage. We find that ependymal cells are not migrating subsequent to their last division, but rather stay where they were first produced. Most interestingly, they can be generated through both symmetric and asymmetric cell division. We also show that embryonic neural stem cells divide asymmetrically to give rise to both an ependymal cell and an adult stem cell. We are confident that these data bring major new insights in the current understanding of neural development. Additionally, these findingscould contribute in opening new therapeutic perspectives and strategies to cure neurodegenerative diseases in a much longer term
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Ozmadenci, Duygu. "Netrin-1 function in somatic cell reprogramming and pluripotency." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSE1254/document.
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La pluripotence est la capacité d'une cellule à s'auto-renouveler et à donner toutes les cellules somatiques ainsi que les cellules germinales. Les cellules pluripotentes peuvent être aussi reprogrammées à partir de cellules somatiques, ouvrant ainsi de nouvelles opportunités pour l'utilisation thérapeutique des cellules souches dans le traitement des maladies dégénératives. La connaissance des mécanismes moléculaires, en particulier des voix de signalisation qui contrôlent la pluripotence, est cruciale pour l'amélioration de notre compréhension de l'embryogenèse précoce et l'utilisation des iPSC (cellules souches pluripotentes induites) dans la médicine régénérative. Ici, je donne la première description de la Nétrine-1 en tant que régulateur de la reprogrammation et de la pluripotence. La Nétrine-1 et ses récepteurs ont été initialement caractérisés dans le système neuronal, mais il a aussi été montré qu'ils étaient exprimés dans différents types cellulaires et impliqués dans divers processus. Dans la première partie, j'ai contribué à explorer comment Nétrine-1 empêche l'apoptose médiée par son récepteur à dépendance DCC (Deleted in Colon Carcinoma) pendant la reprogrammation. Dans la deuxième partie, j'ai disséqué les fonctions et la régulation de cette voie dans le maintien de la pluripotence et dans l'engagement des lignages<br>Pluripotency is the ability of embryonic epiblast cells to self-renew and to give rise to all somatic cells as well as germ cells. Somatic cells can also be reprogrammed toward pluripotency, opening new avenues for stem cell based therapies in the treatment of degenerative diseases. Deciphering the molecular mechanisms, and in particular signaling pathways that control pluripotency is crucial to improve our understanding of early embryogenesis and the use of iPSC (inducible Pluripotent Stem Cell) in regenerative medicine.Herein, I provide the first description of Netrin-1 as a regulator of reprogramming and pluripotency. Netrin-1 and its receptors are present in many cell types and are engaged in a variety of cellular processes beyond its initial characterization in the neuronal system. In the first part, I contributed to explore how Netrin-1 prevents apoptosis mediated by its dependence receptor DCC (Deleted in Colon Carcinoma) during reprogramming. In the second part, I dissected the functions and regulation of this pathway in pluripotency maintenance and in lineage commitment
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Mabrok, Hoda Hussein Bakr. "Protective role of lignan-converting bacteria on chemically-induced breast cancer in gnotobiotic rats." Phd thesis, Universität Potsdam, 2013. http://opus.kobv.de/ubp/volltexte/2013/6493/.
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Enterolignans (enterodiol and enterolactone) exhibit structural similarity to estradiol and have therefore been hypothesized to modulate hormone related cancers such as breast cancer. The bioactivation of the plant lignan secoisolariciresinol diglucoside (SDG) requires the transformation by intestinal bacteria including the deglycosylation of SDG to secoisolariciresinol (SECO) followed by demethylation and dehydroxylation of SECO to enterodiol (ED). Finally, ED is dehydrogenated to enterolactone (EL). It is unclear whether the bacterial activation of SDG to ED and EL is crucial for the cancer preventing effects of dietary lignans. The possible protective effect of bacterial lignan transformation on a 7,12 dimethylbenz(a)anthracene (DMBA)-induced breast cancer in gnotobiotic rats was investigated. Germ-free rats were associated with a defined lignan-converting consortium (Clostridium saccharogumia, Blautia producta, Eggerthella lenta, and Lactonifactor longoviformis). The rats colonized with lignan-converting bacteria consortium (LCC) were fed a lignan-rich flaxseed diet and breast cancer was chemical induced. Identically treated germ-free rats served as control. All bacteria of the consortium successfully colonized the intestine of the LCC rats. The plant lignan SDG was converted into the enterolignans ED and EL in the LCC rats but not in the germ-free rats. This transformation did not influence cancer incidence but significantly decreased tumor numbers per tumor-bearing rat, and tumor size. Cell proliferation was significantly inhibited and apoptosis was significantly induced in LCC rats. No differences between LCC and control rats were observed in the expression of the genes encoding the estrogen receptors (ERα and ERβ) and G-coupled protein receptor 30 (GPR30). Similar findings were observed for both insulin-like growth factor 1 (IGF-1) and epidermal growth factor receptor (EGFR) genes involved in tumor growth. Proteome analysis revealed that 24 proteins were differentially expressed in tumor tissue from LCC and germ-free. RanBP-type and C3HC4-type zinc finger-containing protein 1 (RBCK1) and poly(rC)-binding protein 1 (PBCP1) were down-regulated by 3.2- and 2.0-fold, respectively. These proteins are associated with cell proliferation. The activity of selected enzymes involved in the degradation of oxidants in plasma and liver was significantly increased in the LCC rats. However, plasma and liver concentrations of reduced glutathione (non-enzymatic antioxidant) and malondialdehyde (oxidative stress marker) did not differ between the groups. In conclusion, the bacterial conversion of plant lignan to enterolignans beneficially influences their anti-cancer effect. However, the mechanisms involved in these effects remain elusive.<br>Enterolignanen (Enterodiol ED und Enterolacton EL) wird aufgrund ihrer strukturellen Ähnlichkeit zu Estradiol ein modulierender Einfluss auf hormonell bedingte Krebserkrankungen wie Brustkrebs nachgesagt. Das pflanzliche Lignan Secoisolariciresinoldiglucosid (SDG) wird durch Darmbakterien zum Enterolignan aktiviert. Dies erfolgt über dessen Deglykosylierung zu Secoisolariciresinol (SECO) gefolgt durch die Demethylierung und die Dehydroxylierung zu Enterodiol (ED). Schließlich wird ED zu Enterolacton (EL) dehydrogeniert. Es ist allerdings noch nicht bewiesen, dass die bakterielle Aktivierung von SDG zu ED und EL für die antikanzerogenen Wirkungen verantwortlich ist, die für dieses in der menschlichen Ernährung vorkommende Lignan beschrieben wurden. Um dies zu klären, wurde der Einfluss der bakteriellen Lignan-Transformation auf die Protektion gegenüber einem durch 7,12-Dimethylbenz(a)anthracen (DMBA)-induzierten Brustkrebs im gnotobiotischen Rattenmodell untersucht. Keimfreie Ratten wurden hierfür mit einem Konsortium aus vier Bakterienstämmen (Clostridium saccharogumia, Blautia producta, Eggerthella lenta, und Lactonifactor longoviformis) besiedelt, das die Umsetzung von SDG zu ED und EL katalysiert (LCC-Ratten). Ratten, die über den gesamten Versuchszeitraum keimfrei blieben, dienten als Kontrolle. Die Tiere wurden über 16 Wochen mit einer Leinsamen-Diät gefüttert, die reich an pflanzlichen Lignanen war. Während der Fütterung wurde bei allen Tieren Brustkrebs chemisch induziert.
Das pflanzliche Lignan SDG wurde nur in den LCC Ratten zu den Enterolignanen ED und EL umgewandelt. Keimfreie Ratten zeigten keine Transformation von SDG. Die bakterielle Transformation von SDG hatte zwar keinen Einfluss auf die Inzidenz von Brustkrebs, jedoch verringerten sich durch die Besiedlung der Ratten mit SDG-transformierenden Bakterien die Anzahl von Tumoren pro tumortragender Ratte und die Tumorgröße deutlich. Zudem wurde die Zellproliferation in den LCC-Ratten deutlich gehemmt und die Apoptose induziert. Unterschiede in der Genexpression der Östrogenrezeptoren (ERα und ERß) und G-Protein-gekoppelte Rezeptoren (GPR30) wurden zwischen den LCC-Ratten und den Kontrolltieren nicht beobachtet. Ebenso verhielt es sich für die Gene des Insulinähnliche Wachstumsfaktoren 1 (IGF-1) und Epidermale Wachstumsfaktor rezeptoren (EGFR), welche in das Tumorwachstum involviert sind. Die Analyse des Proteoms des Tumorgewebes ergab 24 differentiell exprimierte Proteine zwischen keimfreien und LCC-Ratten. So wurden zum Beispiel die Proteine RanBP-type and C3HC4-type zinc finger-containing protein 1 (RBCK1) und poly(rC)-binding protein 1 (PBCP1), die mit der Zellproliferation assoziiert sind, in LCC-Ratten um das 3,2 bzw. 2,0-fache herunterreguliert. Die Aktivität ausgewählter antioxidativer Enzyme in Plasma und Leber war in den LCC-Ratten im Vergleich zu den keimfreien Tieren deutlich erhöht. Allerdings unterschieden sich die Konzentrationen von reduziertem Glutathion (nichtenzymatisches Antioxidans) und Malondialdehyd (oxidativer Stress-Marker) in Plasma und Leber nicht zwischen den beiden Besiedlungs-Gruppen.
Zusammenfassend zeigen die Ergebnisse, dass die bakterielle Umwandlung von pflanzlichen Lignanen zu Enterolignanen deren antikanzerogene Wirkung entscheidend beeinflusst. Allerdings bleiben die zugrunde liegenden Mechanismen weiterhin ungeklärt.
Books on the topic "Cell lignage"
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Marque, Paul. La ligne Maginot aquatique: Celle qui résista en 1940 dans la trouée de la Sarre. Editions Pierron, 1989.
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Edwards, M. J. ATCC microbes & cells at work: An index to ATCC strains with special applications. American Type Culture Collection, 1988.
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Liu, Zhi-Jian. The effects of calcium, short chain fatty acids and mammalian lignans on calcium transport, intracellular Ca2+ and intracellular pH in the human colon tumor cells HCT-15. National Library of Canada, 2000.
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Patin, Stéphane, ed. Les enjeux du numérique en sciences sociales et humaines. Editions des archives contemporaines, 2020. http://dx.doi.org/10.17184/eac.9782813003867.
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Devenu « univers », « ère », « révolution » ou même « culture », le numérique est un phénomène technologique, social et culturel qui affecte les activités les plus ordinaires de notre vie quotidienne. Il modifie notre rapport à la temporalité −immédiateté, simultanéité, accélération− et à l’espace où nous sommes passés successivement d’une culture sédentaire, celle de la chaise et d’ un ordinateur du web 1.0 ; à une culture nomade, celle des dispositifs mobiles du web 2.0. Il change sinon bouleverse nos relations interpersonnelles, nos modes de penser, d’imaginer et de créer, de travailler, d’accéder au savoir ainsi que nos façons de produire et de diffuser les connaissances et les expériences du monde. En français et en espagnol, les onze contributions d’enseignants-chercheurs et de professionnels réunies dans cet ouvrage mettent en lumière comment, au XXIe siècle, le numérique touche aussi bien la _praxis_ que _l’épistémè_ des sciences humaines. Analyse discursive de SMS, de messages sur_ WhatsApp_, de _Tweets_, de commentaires en ligne, de textes juridiques et statutaires, didactisation des outils numériques en langues maternelles, traduction et adaptation de spots publicitaires, pratique numérique dans le tourisme culturel, numérisation de collections à la Bibliothèque nationale de France ou au Château de Versailles, diffusion de séries sur des plateformes numériques sont autant d’exemples qui témoignent d’ une humanité technologique façonnée par le numérique… Un numérique ouvrant la voie à un éventuel _homo numericus_ doté d’une multitude d’écrans et de claviers lui obéissant au doigt et à l’œil.
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Hare, Brian, and Shinya Yamamoto. Minding the bonobo mind. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198728511.003.0001.
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We illustrate the central role the bonobo plays in testing evolutionary hypotheses regarding ape minds (including our own). The importance of bonobos has become apparent only recently with sustained fieldwork at multiple sites in the Congo Basin as well as the first direct quantitative comparisons between bonobos, chimpanzees and humans. This recent work has revealed a number of traits in which bonobos and chimpanzees are more similar to humans than they are to each other. This means that bonobos are crucial to determining the evolutionary processes by which cognitive traits evolved in our own lineage. Based on the evidence within, it becomes clear that one can no longer know chimpanzees or humans without also knowing bonobos. We argue this makes investing in bonobo research and improved protection for bonobos in captivity and the wild an even higher priority. Nous illustrons le rôle central joué par le bonobo pour tester les hypothèses relatives à l’évolution de l’esprit des grands singes (y compris le nôtre). L’importance des bonobos n’est apparue que récemment grâce à un travail de terrain soutenu sur de multiples sites dans le bassin du Congo ainsi qu’aux premières comparaisons quantitatives directes entre les bonobos, les chimpanzés et les humains. Ces récents travaux ont révélé un certain nombre de caractéristiques pour lesquelles les bonobos et les chimpanzés présentent plus de similarités avec les humains que l’un envers l’autre. Cela signifie que les bonobos sont essentiels pour déterminer les processus d’évolution par lesquels les caractéristiques cognitives ont évolué dans notre propre lignée. Sur la base des preuves contenues dans ce document, il devient clair que l’on ne peut plus connaître les chimpanzés ou les humains sans connaître les bonobos. Cela rend donc d’autant plus primordiaux l’investissement dans la recherche sur les bonobos et l’amélioration de la protection des bonobos en captivité comme à l’état sauvage.
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Liede-Schumann, Sigrid, Ulrich Meve, Gildas Gâteblé, Gabrielle Barriera, and Silvio Fici. Apocynaceae pro parte, Phellinaceae, Capparaceae : Flore de la Nouvelle Calédonie, volume 27. Publications scientifiques du Muséum, Paris ; IRD, Marseille, 2020. http://dx.doi.org/10.5852/fft49.
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L’exceptionnelle richesse floristique de la Nouvelle-Calédonie est mondialement connue. Plus de 3 400 espèces de plantes vasculaires indigènes y sont répertoriées, dont les trois-quarts sont endémiques de l’archipel. L’endémisme ne concerne pas seulement les espèces, mais aussi les genres (près d’une centaine) et même trois familles. La diversité se décline aussi sur le plan écologique, en lien avec l’histoire géologique originale de la Nouvelle-Calédonie, qui a favorisé le micro-endémisme et les espèces inféodées aux substrats ultramafiques. De nouvelles espèces continuent à être découvertes, aussi reste-t-il nécessaire de poursuivre prospections et recherches botaniques, afin de mieux comprendre l’origine et l’évolution de cette flore, et contribuer à sa préservation. Le présent volume regroupe trois familles d’Angiospermes. Celle des Apocynaceae dont la classification a été profondément remaniée depuis la publication en 1981 du fascicule « Apocynaceae », volume 10 de la Flore de la Nouvelle-Calédonie et Dépendances : les trois sous-familles traitées ici (Periplocoideae, Secamonoideae et Asclepiadoideae) formaient auparavant la famille des Asclepiadaceae. Les Phellinaceae qui, avec 10 espèces ligneuses, constituent l’une des trois familles endémiques du territoire. Enfin, la Nouvelle-Calédonie héberge quelques espèces de la famille cosmopolite des Capparaceae, toutes appartenant au genre du câprier (Capparis). Conformément à la ligne éditoriale de la collection, cet ouvrage comporte, pour chaque famille traitée indépendamment : une présentation générale suivie de descriptions détaillées des genres et des espèces ; des clés d’identification, en français et en anglais ; une illustration variée comprenant des dessins au trait et des photographies des plantes vivantes ; des cartes de répartition et une évaluation des besoins de conservation selon les critères de l’UICN.
Book chapters on the topic "Cell lignage"
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Saarinen, Niina, Sari Mäkelä, and Risto Santti. "Anticancer Effects of Lignans." In Animal Cell Technology: Basic & Applied Aspects. Springer Netherlands, 2003. http://dx.doi.org/10.1007/978-94-017-0726-8_10.
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Ladurner, Peter, Bernhard Egger, Katrien De Mulder, et al. "The Stem Cell System of the Basal Flatworm Macrostomum lignano." In Stem Cells. Springer Netherlands, 2008. http://dx.doi.org/10.1007/978-1-4020-8274-0_5.
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Silva, Cláudia Gontijo, Vera Lúcia de Almeida, Priscilla Rodrigues Valadares Campana, and Marina Pereira Rocha. "Plant Cell Cultures as Producers of Secondary Metabolites: Podophyllum Lignans as a Model." In Reference Series in Phytochemistry. Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-28669-3_3.
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Silva, Cláudia Gontijo, Vera Lúcia de Almeida, Priscilla Rodrigues Valadares Campana, and Marina Pereira Rocha. "Plant Cell Cultures as Producers of Secondary Metabolites: Podophyllum Lignans as a Model." In Transgenesis and Secondary Metabolism. Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-27490-4_3-1.
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Gabr, Ahmed M. M., Hoda B. Mabrok, Oksana Sytar, and Iryna Smetanska. "Recent Advances Toward Development of Plant Cell Culture Process for Sustainable Production of Lignans and Their Health Benefits." In Exploring Plant Cells for the Production of Compounds of Interest. Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-58271-5_10.
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Xiao, Hui-Hui, Man-Sau Wong, and Xin-Sheng Yao. "A Lignan-Rich Bioactive Fraction of Sambucus williamsii Hance Exerts Oestrogen-Like Bone Protective Effects in Aged Ovariectomized Rats and Osteoblastic Cells." In Nutritional Influences on Bone Health. Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-32417-3_13.
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Xu, Jingwen, and Weiqun Wang. "Fiber-associated wheat lignans and colorectal cancer prevention." In Improving the nutritional and nutraceutical properties of wheat and other cereals. Burleigh Dodds Science Publishing, 2021. http://dx.doi.org/10.19103/as.2021.0087.10.
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Wheat, as a staple food, has been largely consumed worldwide. In addition to nutritional values, whole grain including fiber-enriched wheat bran has been reported to provide many nutraceuticals such as wheat lignans. This chapter reviews recent epidemiological and animal data on wheat lignans and their role in colorectal cancer prevention. It covers aspects of the lignan structure, biosynthesis, analysis, metabolism and potential health benefits with emphasis on anti-proliferative, anti-oxidant, anti-inflammation, anti-estrogenic and cell cycle arrest mechanisms. Human epidemiological studies suggest dietary intake of lignans is associated with reducing risk of many chronic diseases such as cardiovascular disease, chronic bowel inflammation, and certain types of cancer including colorectal cancer. The bioactivity of wheat lignans has been shown to be influenced by their chemical forms and microbial flora-induced metabolites. Compelling animal study data suggest that dietary lignans or wheat lignans contribute to colorectal cancer prevention; however, further clinical intervention studies appear warranted.
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Zaprometov, M. N. "Tannins, Lignans, and Lignins." In Phytochemicals in Plant Cell Cultures. Elsevier, 1988. http://dx.doi.org/10.1016/b978-0-12-715005-5.50012-1.
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Henry, Albert. "Tel/Cel : Un couple fumeux." In La ligne claire. De Boeck Supérieur, 1998. http://dx.doi.org/10.3917/dbu.pierr.1998.01.0055.
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Rollet, Catherine. "Une histoire d’annonces. Temporalités et manières de faire d’hier à aujourd’hui." In Naître et grandir. Normes du Sud, du Nord, d’hier et d’aujourd’hui. Editions des archives contemporaines, 2020. http://dx.doi.org/10.17184/eac.3165.
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Annoncer la naissance d’un enfant a toujours représenté un moment fort de la vie des familles puisque cette annonce sort l’événement de la sphère familiale et du lignage pour le rendre public. Cette annonce peut être précédée par plusieurs autres, celle de la grossesse, du sexe présumé, espéré ou connu de l’enfant à venir, de son prénom. Autant d’étapes dans la publicisation de la naissance qui appellent l’attention des historiens, des sociologues et plus généralement des sciences sociales. Dans cet article, nous tenterons d’une part une synthèse, très partielle, des pratiques de ces annonces au cours des XVIIIe-XXe siècles pour aborder dans une dernière partie les manières actuelles de passer de l’intime au « public » au travers d’une enquête récente menée en France. Nos questions de recherche peuvent être résumées de la façon suivante : quelles temporalités hier et aujourd’hui, les parents suivent-ils pour annoncer la naissance future de leur enfant ? A quel cercle familial et social font-ils cette ou ces annonces ? Enfin, existe-t-il une hiérarchie dans l’annonce, certains faits étant révélés avant la naissance, d’autres réservés à l’après naissance ?
Conference papers on the topic "Cell lignage"
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Christofidou-Solomidou, Melpo, James C. Lee, Floyd Dukes, et al. "FLAXSEED LIGNANS PROTECT NORMAL LUNG ENDOTHELIAL CELLS FROM RADIATION-INDUCED OXIDATIVE CELL AND DNA DAMAGE." In American Thoracic Society 2010 International Conference, May 14-19, 2010 • New Orleans. American Thoracic Society, 2010. http://dx.doi.org/10.1164/ajrccm-conference.2010.181.1_meetingabstracts.a2004.
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Zhu, Xin, Chang’an Wang, Chunli Tang, and Defu Che. "Energy Analysis of a Lignite-Fueled Power Plant With a Two-Stage Predrying System." In ASME 2017 Power Conference Joint With ICOPE-17 collocated with the ASME 2017 11th International Conference on Energy Sustainability, the ASME 2017 15th International Conference on Fuel Cell Science, Engineering and Technology, and the ASME 2017 Nuclear Forum. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/power-icope2017-3180.
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Performance of lignite-fueled power plants can be improved by predrying the lignite and it is influenced by the characteristics of drying heat source. Heat source for lignite predrying in power plants can be high-temperature flue gas, boiler exhaust gas and extraction steam. Nevertheless, balance point among drying safety, lignite drying degree and drying thermal economy cannot be located using single drying heat source. In this study, a lignite-fueled power plant with a two-stage drying system was proposed. The drying system mainly contains two fluidized bed dryers — the first stage dryer and the second stage dryer. Boiler exhaust gas and extraction steam supply the heat, respectively. The proposed power plant can attain higher lignite drying degree than the power plant in which only boiler exhaust was employed. The new power plant also features higher overall efficiency for the same lignite drying degree compared with extraction steam drying power plant..
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Huebel, Moritz, Juergen Nocke, Sebastian Meinke, and Egon Hassel. "Identification of Energy Storage Capacities Within Large-Scale Power Plants and Development of Control Strategies to Increase Marketable Grid Services." In ASME 2015 Power Conference collocated with the ASME 2015 9th International Conference on Energy Sustainability, the ASME 2015 13th International Conference on Fuel Cell Science, Engineering and Technology, and the ASME 2015 Nuclear Forum. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/power2015-49179.
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In order to meet future demands, existing and new plants need to be optimized to offer additional control reserves to stabilize an electrical grid, which is highly penetrated by fluctuating renewables. Since this requires a dynamic investigation, transient physical based models of different power plants have been developed to evaluate effects of increased flexibility as well as to develop optimization strategies. The approach has been tested for a specific 500 MW lignite-fired power plant. It includes detailed modeling of the incorporated sub-systems and their interactions as well as the implementation of the power plant’s control system. The dynamic simulation model is used for the identification of energy storage potentials within the process and for testing and developing control strategies in order to increase flexibility and marketable output of the process. The strategies are benchmarked and evaluated based on the consideration of exergetic efficiency and lifetime-consumption of critical components.
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Nomura, Risa, Norihiko Iki, Osamu Kurata, et al. "System Analysis of IGFC With Exergy Recuperation Utilizing Low-Grade Coal." In ASME 2011 Turbo Expo: Turbine Technical Conference and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/gt2011-46282.
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Integrated Coal Gasification Fuel Cell Combined Cycle (IGFC) is expected to be the most efficient power generation system in coal fired power generation systems [1,2]. The Japanese project of the Strategic Technical Platform for Clean Coal Technology (STEP-CCT) aims a target efficiency of 65% (HHV) with exergy recuperation. We have been analyzing the processes of the exergy recuperated Integrated Coal Gasification Combined Cycle (IGCC) and the Advanced IGCC (A-IGCC) [3] which is expected to be realized in 2040. Previous studies have indicated a limitation of the quantity of high temperature steam in the case of auto-thermal reactions with the fluidized bed coal gasifier in the A-IGCC, in particular for TIT 1500 °C class gas turbine. The Advanced IGFC (A-IGFC) system can reduce the exergy loss resulting from combustion, and its ‘exergy recuperation’ is appealing. The waste heat exhausted from the fuel cells is recycled to the gasifier for steam reforming in an endothermic reaction with a low exergy loss and a high cold gas efficiency. Our current study focuses on the optimization of the unit configurations of the A-IGFC including gasifier, compressor, solid oxide fuel cell (SOFC), combustor, gas turbine, heat recovery steam generator (HRSG), and steam turbine. The process simulator HYSYS®.Plant (Aspen technology Inc.) is employed in order to express the gasifier, the SOFC and the other units. The optimum construction over the whole system by numerical simulation was examined for higher energy utilization efficiency. Under ideal conditions using bituminous coal, we verified the power generation efficiency to be 64.5% (HHV). However, utilizing low-grade coals, i.e., lignite and sub-bituminous coal, is deemed an important future energy resource to compensate for a decreasing supply of good-quality bituminous coal. For these low-grade coals, the power generation efficiency was as high as 53.6% (HHV) under the following conditions: Gasifier inlet: coal 23.6 Kg/s (667 MJ/s), steam 16.44 kg/s; Reactor reforming gas: 30.0, 8.7, 2.0, 0.8, 0.3, 0.05, 0.24, 0.14, 0.1 and 5.5 kg/s for CO, CO2, H2, CH4, C2H4, C2H6, C3H6, HCN, N2 and H2O respectively. The projected power outputs with this system were, SOFC: 214 MW; Gas turbine: 318 MW; Steam turbine: 86 MW.
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Meng, Haiyu, Shuzhong Wang, Lin Chen, Wu Zhiqiang, and Jun Zhao. "Investigation on Gaseous Product Distributions During Co-Pyrolysis of Platanus Wood and Different Rank Coals From Northwestern China in a Drop Tube Furnace." In ASME 2015 Power Conference collocated with the ASME 2015 9th International Conference on Energy Sustainability, the ASME 2015 13th International Conference on Fuel Cell Science, Engineering and Technology, and the ASME 2015 Nuclear Forum. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/power2015-49073.
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Co-thermochemical conversion of municipal solid waste blends with coal has the advantage of diversifying energy resources and decreasing consumption of fossil fuels. As the initial and fundamental stage of co-thermochemical conversion, co-pyrolysis of municipal solid waste and coal has important influence on performance of the further co-combustion or co-gasification process. In this paper, gaseous product distributions during co-pyrolysis of platanus wood (wood waste from urban roadside trees platanus acerifolia) and two different rank coals (Shenmu bituminous and Pingzhuang lignite from northwestern China) were investigated through a semi-batch type drop tube furnace at different temperatures. The platanus wood/coal blends were fed into the furnace with five different mass ratios of 100/0, 70/30, 50/50, 30/70, and 0/100. The gaseous products (H2, CO, CO2, CH4 and light hydrocarbons) were continuously collected and then determined by gas chromatography. Experimental results indicated that the gaseous product distributions from pyrolysis of the platanus wood and coal blends were significantly affected by the temperature, the platanus wood/coal mass ratio and coal type. Compared the experimental results with the calculated values obtained from individual samples based on weighted average, some signs about positive or negative synergistic effect were observed on the formation of the major gas composition. The synergistic effect could probably be caused by the secondary reactions between volatiles and chars. In addition, the coal rank appeared to have different influence on the synergistic effect between platanus wood and coal during co-pyrolysis process.
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Cardoso, Evani Ferreira, Rodrigo de Souza Miranda, Roberto Carlos Campos Martins, Gunar Vingre da Silva Mota, Antônio Maia de Jesus Chaves Neto, and Fábio Luiz Paranhos Costa. "Uso de Cálculos de RMN de 13C e 1H e Redes Neurais no Auxilio da Determinação Estrutural da Savinina." In VIII Simpósio de Estrutura Eletrônica e Dinâmica Molecular. Universidade de Brasília, 2020. http://dx.doi.org/10.21826/viiiseedmol2020178.
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This is a theoretical-experimental work, where the focus molecule of the study is savinine, a lignan of the dibenzylbutyrolactonic type, substances that can be found in several genera, one of which has a greater occurrence is the genus Acanthopanax (Araliaceae) which is traditionally used as an analgesic and immune system stimulant, in addition to exhibiting a potent insecticidal and cytotoxic activity for human colon carcinoma HCT116 cells. It was isolated and here we present its experimental and theoretical characterization by means of 13C and 1H NMR data and the possible confirmation of the structure using the neural network tool (ANN-PRA). The objective of this work is to use theoretical calculations of 13C and 1H NMR and experimental data for the resolution of the savinine structure, and the use of the neural network tool (ANN-PRA) to confirm the structure of the molecule.
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Christofidou-Solomidou, Melpo, Ralph Pietrofesa, and Steven Albelda. "Novel Synthetic lignan reduces asbestos-induced damage in human pleural mesothelial cells-Potential clinical usefulness in inhibiting pleural malignant mesothelioma." In ERS International Congress 2017 abstracts. European Respiratory Society, 2017. http://dx.doi.org/10.1183/1393003.congress-2017.pa1581.
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Prisecaru, Tudor I., Elena Popa, and Malina Mihaela Prisecaru. "CFD Air Flow Channel Optimization for a Low NOx Operation of a Big Steam Boiler." In ASME/JSME 2007 5th Joint Fluids Engineering Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/fedsm2007-37057.
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One of the Romanian big power plant (Turceni) of 2400 MWe installed power has seven Benson boilers of 1035 t/h each, using Romanian pulverized lignite. Until 2008, every one of them has to be revamped in order to emit less than 500 mg/Nm3 of NOx at full load and 6% oxygen content in the flue gas. The problem has been very complex due to the fact that all these steam boilers have been commissioned since 1968, without any design preparation concerning low NOx emissions. Step by step, all the technological measures have been performed, so the burning process of the Romanian low heat power lignite, has been able to produce low NOx emissions by the help of supplementary stages of air injections. The last problem and the subject of the presented paper, occurred regarding the possibility to inject enough and equal airflow rate through sixteen nozzles before the end of the boiler’s furnace. The complexity of this problem consisted not only in a lot of technical constraints concerning to the starting place of the air pipes, but also to the path of the pipes (with very big dimensions) and to a very low influence in pressure drop losses towards the existent air ducts. A special supplementary problem has been that one to create the simplest shape of the air inlet elbow from the main existent air ducts, in order to suck the strictly necessary airflow rate at the lowest possible pressure drop loss. Due to the fact that the boiler’s dimensions are too big to use only one air pipe toward the nozzles, two air manifolds are considered starting from two main different air ducts and feeding eight nozzles each; this fact has complicated the task further, in order to balance the airflow rate inside the two manifolds. This complex problem has been solved by the help of CFD Fluent code and has been considered also the subject of one of the team member’s PhD dissertation. Special meshing techniques have been used in order to optimize the cells’ number. For CFD results validation a special 1:50 transparent scaled model of the furnace has been constructed and performed using a laser — Doppler anemometer to determine the airflow rate and velocity, inside the air channels and at the nozzles’ exits to the furnace.
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Dabrosin, C., G. Lindahl, A. Abrahamsson, and N. Saarinen. "Abstract P1-02-06: Tamoxifen, Flaxseed and the Lignan Enterolactone Increase Stroma and Cancer Cell Derived IL-1Ra, Decrease Tumor Growth and Angiogenesis in Estrogen Dependent Breast Cancer Explants." In Abstracts: Thirty-Third Annual CTRC‐AACR San Antonio Breast Cancer Symposium‐‐ Dec 8‐12, 2010; San Antonio, TX. American Association for Cancer Research, 2010. http://dx.doi.org/10.1158/0008-5472.sabcs10-p1-02-06.
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KIM, Won Kyung, Min Ai LEE, Hyen Joo PARK, Ji-Young HONG, Sam Sik KANG та Sang Kook LEE. "Abstract 5547: Anti-proliferative activity of hydnocarpin, a natural lignan, is associated with the inhibition of Wnt/β-catenin signaling pathway via axin turnover in colon cancer cells". У Proceedings: AACR 106th Annual Meeting 2015; April 18-22, 2015; Philadelphia, PA. American Association for Cancer Research, 2015. http://dx.doi.org/10.1158/1538-7445.am2015-5547.
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