195 research outputs found

    Development of freshwater prawn (Macrobrachium rosenbergii) seed production and culture technology in the Mekong Delta Region of Vietnam: A review of the JIRCAS Project at Cantho University.

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    The Mekong Delta of Vietnam is a region rich in aquatic resources having high potential for aquaculture development. Inland aquaculture in the Mekong Delta has greatly increased since the last decade. Fish culture carried out in combination with other agricultural activities such as animal husbandry and rice cultivation, and intensive aquaculture in ponds and cages have been the dominant forms of fish production. However, the giant freshwater prawn, Macrobrachium rosenbergii, has recently become a species of economic significance and the target of aquaculture activity in the Mekong Delta. M. rosenbergii is cultured throughout the region in the rice fields, ponds, orchard gardens and in pens along river banks. The major constraints in this industry are seed supply and culture techniques, becoming the major obstacles for the further development of the culture of this species. In a collaborative research project implemented between the Japan International Research Center for Agricultural Sciences (JIRCAS) and Cantho University (CTU) since 1994, studies have been carried out on various aspects relating to the establishment of M. rosenbergii seed production and culture technology. The project is now in the middle of its second phase and has generated a great deal of scientific and practical information. This paper presents an overview of the achievements of this project

    Selective interlayer ferromagnetic coupling between the Cu spins in YBa2_2 Cu3_3 O7x_{7-x} grown on top of La0.7_{0.7} Ca0.3_{0.3} MnO3_3

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    Studies to date on ferromagnet/d-wave superconductor heterostructures focus mainly on the effects at or near the interfaces while the response of bulk properties to heterostructuring is overlooked. Here we use resonant soft x-ray scattering spectroscopy to reveal a novel c-axis ferromagnetic coupling between the in-plane Cu spins in YBa2_2 Cu3_3 O7x_{7-x} (YBCO) superconductor when it is grown on top of ferromagnetic La0.7_{0.7} Ca0.3_{0.3} MnO3_3 (LCMO) manganite layer. This coupling, present in both normal and superconducting states of YBCO, is sensitive to the interfacial termination such that it is only observed in bilayers with MnO_2but not with La0.7_{0.7} Ca0.3_{0.3} interfacial termination. Such contrasting behaviors, we propose, are due to distinct energetic of CuO chain and CuO2_2 plane at the La0.7_{0.7} Ca0.3_{0.3} and MnO2_2 terminated interfaces respectively, therefore influencing the transfer of spin-polarized electrons from manganite to cuprate differently. Our findings suggest that the superconducting/ferromagnetic bilayers with proper interfacial engineering can be good candidates for searching the theorized Fulde-Ferrel-Larkin-Ovchinnikov (FFLO) state in cuprates and studying the competing quantum orders in highly correlated electron systems.Comment: Please note the change of the title. Text might be slightly different from the published versio

    Epigenetics as a mechanism driving polygenic clinical drug resistance

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    Aberrant methylation of CpG islands located at or near gene promoters is associated with inactivation of gene expression during tumour development. It is increasingly recognised that such epimutations may occur at a much higher frequency than gene mutation and therefore have a greater impact on selection of subpopulations of cells during tumour progression or acquisition of resistance to anticancer drugs. Although laboratory-based models of acquired resistance to anticancer agents tend to focus on specific genes or biochemical pathways, such 'one gene : one outcome' models may be an oversimplification of acquired resistance to treatment of cancer patients. Instead, clinical drug resistance may be due to changes in expression of a large number of genes that have a cumulative impact on chemosensitivity. Aberrant CpG island methylation of multiple genes occurring in a nonrandom manner during tumour development and during the acquisition of drug resistance provides a mechanism whereby expression of multiple genes could be affected simultaneously resulting in polygenic clinical drug resistance. If simultaneous epigenetic regulation of multiple genes is indeed a major driving force behind acquired resistance of patients' tumour to anticancer agents, this has important implications for biomarker studies of clinical outcome following chemotherapy and for clinical approaches designed to circumvent or modulate drug resistance

    Étude ethnobotanique et screening phytochimique de Caesalpinia benthamiana (Baill.) Herend. et Zarucchi (Caesalpiniaceae)

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    Les informations ethnobotaniques obtenues auprès de dix (10) tradithérapeutes du canton N\'Gadié dans le Département d\'Adzopé montrent que l\'utilisation de Caesalpinia benthamiana (Caesalpiniaceae) (Cb) contribue significativement aux soins de santé primaire pour le traitement des troubles de l\'érection. En effet, sur les quinze (15) espèces de plantes médicinales (réparties entre 14 familles) utilisées pour le traitement de diverses pathologies liées aux troubles de l\'érection, Cb est la plus fréquemment prescrite dans ledit canton. Un screening phytochimique réalisé sur cinq (5) extraits bruts des racines de Cb a révélé qu\'elles renferment des stérols, polyterpènes, flavonoïdes, saponines, tannins, sucres réducteurs, coumarines et des protéines.Ethnobotanical Informations obtained beside ten (10) traditional herbalists of the canton N\'Gadie in the Department of Adzope show that the use of Caesalpinia benthamiana(Caesalpiniaceae) (Cb) contributes significantly to primary health cares for the processing of erectile troubles. Indeed, on the fifteen (15) species of plant medicinal (distributed between 14 families) used for the various pathology processing linked to erectile troubles, Cb is the most frequently prescribed in the aforementioned canton. A phytochemical screening realized on five (5) extracted crude of roots of Cb has revealed that they contain the sterols, polyterpenes, flavonoids, saponines, tannins, reducing sugars, coumarins and proteins. Keywords: pharmacopée traditionnelle, Côte d\'Ivoire, Adzopé, screening phytochimique, érection, Caesalpinia benthamiana(Caesalpiniaceae)/traditional pharmacopoeia, Côte d'Ivoire, Adzope, erection, Caesalpinia benthamiana (Caesalpiniaceae)Sciences & Nature Vol. 4 (2) 2007: pp. 217-22

    The freshwater Sponge Ephydatia Fluviatilis harbours diverse pseudomonas species (Gammaproteobacteria, Pseudomonadales) with broad-spectrum antimicrobial activity

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    Bacteria are believed to play an important role in the fitness and biochemistry of sponges (Porifera). Pseudomonas species (Gammaproteobacteria, Pseudomonadales) are capable of colonizing a broad range of eukaryotic hosts, but knowledge of their diversity and function in freshwater invertebrates is rudimentary. We assessed the diversity, structure and antimicrobial activities of Pseudomonas spp. in the freshwater sponge Ephydatia fluviatilis. Polymerase Chain Reaction - Denaturing Gradient Gel Electrophoresis (PCR-DGGE) fingerprints of the global regulator gene gacA revealed distinct structures between sponge-associated and free-living Pseudomonas communities, unveiling previously unsuspected diversity of these assemblages in freshwater. Community structures varied across E. fluviatilis specimens, yet specific gacA phylotypes could be detected by PCR-DGGE in almost all sponge individuals sampled over two consecutive years. By means of whole-genome fingerprinting, 39 distinct genotypes were found within 90 fluorescent Pseudomonas isolates retrieved from E. fluviatilis. High frequency of in vitro antibacterial (49%), antiprotozoan (35%) and anti-oomycetal (32%) activities was found among these isolates, contrasting less-pronounced basidiomycetal (17%) and ascomycetal (8%) antagonism. Culture extracts of highly predation-resistant isolates rapidly caused complete immobility or lysis of cells of the protozoan Colpoda steinii. Isolates tentatively identified as P. jessenii, P. protegens and P. oryzihabitans showed conspicuous inhibitory traits and correspondence with dominant sponge-associated phylotypes registered by cultivation-independent analysis. Our findings suggest that E. fluviatilis hosts both transient and persistent Pseudomonas symbionts displaying antimicrobial activities of potential ecological and biotechnological value.European Regional Development Fund (ERDF) through the COMPETE (Operational Competitiveness Programme); national funds through FCT (Foundation for Science and Technology) [PEst-C/MAR/LA0015/2011]; FCT-funded project [PTDC/BIA-MIC/3865/2012]; Federation of European Microbiological Societies (FEMS)info:eu-repo/semantics/publishedVersio

    Evaluation in vitro de l’activité des écorces de tige de Anogeissus leiocarpus (DC) Guill. et Perr. (Combretaceae) sur des bactéries responsables de maladies courantes en Afrique et criblage phytochimique

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    Les bactéries sont à l’origine de réel problème de santé publique à cause de leur implication dans de nombreuses maladies. Leur résistance aux antibiotiques est devenue l’un des problèmes les plus importants dans la lutte contre les maladies infectieuses dans le monde. L’objectif de ce travail est d’évaluer l’activité antibactérienne des extraits hexanique, méthanolique 70% (v/v) et aqueux des écorces de tige de Anogeissus leiocarpus (DC) Guill. et Perr. (Combretaceae), une plante médicinale de la flore ivoirienne, contre les bactéries des genres Staphylococcus, Pseudomonas et les entérobactéries (Shigella sp., Salmonella Typhimurium, Escherichia coli et Proteus mirabilis) par la méthode de diffusion en milieu gélosé dans des cupules et la méthode de macro-dilution en milieu liquide . Les extraits aqueux et méthanolique 70% (v/v) ont été retenus pour la détermination des paramètres antibactériens (CMI et CMB), en raison de leurs activités sur l’ensemble des bactéries sélectionnées. Par ailleurs, une analyse qualitative par chromatographie sur couche mince (CCM), effectuée sur les différents extraits, a permis de détecter plusieurs groupes de composés chimiques parmi lesquels les saponosides, les tanins, les flavonoïdes, les polyphénols, les alcaloïdes et les sesquiterpènes dont des effets antibactériens sont connus. Les CMI obtenues, sont comprises entre 0,7 ± 0,0 et 12,5 ± 0,0 mg/ml. Quant aux CMB, elles varient de 3,1 ± 0,0 à 25,0 ± 0,0 mg/ml. Ce travail justifie l’utilisation traditionnelle de Anogeissus leiocarpus dans le traitement de diverses pathologies et plus particulièrement celles d’origine bactérienne.Mots clés : Antibactérienne, Anogeissus leiocarpus, flore ivoirienne, analyse qualitative

    Phylogenetically and spatially close marine sponges harbour divergent bacterial communities

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    Recent studies have unravelled the diversity of sponge-associated bacteria that may play essential roles in sponge health and metabolism. Nevertheless, our understanding of this microbiota remains limited to a few host species found in restricted geographical localities, and the extent to which the sponge host determines the composition of its own microbiome remains a matter of debate. We address bacterial abundance and diversity of two temperate marine sponges belonging to the Irciniidae family - Sarcotragus spinosulus and Ircinia variabilis – in the Northeast Atlantic. Epifluorescence microscopy revealed that S. spinosulus hosted significantly more prokaryotic cells than I. variabilis and that prokaryotic abundance in both species was about 4 orders of magnitude higher than in seawater. Polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) profiles of S. spinosulus and I. variabilis differed markedly from each other – with higher number of ribotypes observed in S. spinosulus – and from those of seawater. Four PCR-DGGE bands, two specific to S. spinosulus, one specific to I. variabilis, and one present in both sponge species, affiliated with an uncultured sponge-specific phylogenetic cluster in the order Acidimicrobiales (Actinobacteria). Two PCR-DGGE bands present exclusively in S. spinosulus fingerprints affiliated with one sponge-specific phylogenetic cluster in the phylum Chloroflexi and with sponge-derived sequences in the order Chromatiales (Gammaproteobacteria), respectively. One Alphaproteobacteria band specific to S. spinosulus was placed in an uncultured sponge-specific phylogenetic cluster with a close relationship to the genus Rhodovulum. Our results confirm the hypothesized host-specific composition of bacterial communities between phylogenetically and spatially close sponge species in the Irciniidae family, with S. spinosulus displaying higher bacterial community diversity and distinctiveness than I. variabilis. These findings suggest a pivotal host-driven effect on the shape of the marine sponge microbiome, bearing implications to our current understanding of the distribution of microbial genetic resources in the marine realm.This work was financed by the Portuguese Foundation for Science and Technology (FCT - http://www.fct.pt) through the research project PTDC/MAR/101431/2008. CCPH has a PhD fellowship granted by FCT (Grant No. SFRH/BD/60873/2009). JRX’s research is funded by a FCT postdoctoral fellowship (grant no. SFRH/BPD/62946/2009). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

    Association of nutritional status and serum albumin levels with development of toxicity in patients with advanced non-small cell lung cancer treated with paclitaxel-cisplatin chemotherapy: a prospective study

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    <p>Abstract</p> <p>Background</p> <p>A frequent manifestation of advanced NSCLC is malnutrition, even though there are many studies which relate it with a poor survival, its relation with toxicity has not yet been consistently reported. The aim of this study was to associate malnutrition and albumin serum levels with the occurrence of chemotherapy-induced toxicity in cisplatin plus paclitaxel chemotherapy-treated NSCLC.</p> <p>Methods</p> <p>We prospectively evaluated 100 stage IV NSCLC patients treated with paclitaxel (175 mg/m<sup>2</sup>) and cisplatin (80 mg/m<sup>2</sup>). Malnutrition was assessed using SGA prior treatment. Neutrophil Lymphocyte Ratio (NLR) and the Platelet Lymphocyte Ratio (PLR) were used to determine the presence of systemic inflammatory response (SIR) and were related to the development of toxicity. Toxicity was graded according to NCI CTCAE version 3.0 after two chemotherapy cycles.</p> <p>Results</p> <p>Median age was 58 ± 10 years, 51% of patients were malnourished, 50% had albumin ≤3.0 mg/mL. NLR ≥ 5 was associated with basal hypoalbuminemia (mean ranks, 55.7 vs. 39 p = 0.006), ECOG = 2 (47.2 vs. 55.4 p = 0.026) and PLR ≥ 150 were significantly related with a basal body mass index ≤20 (56.6 vs. 43.5; p = 0.02) and hypoalbuminemia (58.9 vs. 41.3; p = 0.02). Main toxicities observed after 2 cycles of chemotherapy were alopecia (84%), nausea (49%), neuropathy (46%), anemia (33%), lymphopenia (31%), and leukopenia (30%). Patients malnourished and with hypoalbuminemia developed more chemotherapy-induced toxicity overall when compared with those without malnutrition (31 vs 22; <it>p </it>= 0.02) and normal albumin (mean ranks, 62 vs 43; <it>p </it>= 0.002), respectively. Hypoalbuminemia was associated with anemia (56 vs 47; <it>p </it>= 0.05), fatigue (58 vs 46; <it>p </it>= 0.01), and appetite loss (57.1 vs 46.7; <it>p </it>= 0.004) compared with normal albumin. PLR ≥ 150 was related with the development of toxicity grade III/IV (59.27 vs. 47.03 p = 0.008) and anemia (37.9 vs 53.8 p = 0.004).</p> <p>Conclusion</p> <p>SIR parameters were associated with malnutrition, weight loss and hypoalbuminemia. Chemotherapy-induced toxicity in NSCLC patients treated with paclitaxel and cisplatin was associated with malnutrition and hypoalbuminemia. Early nutritional assessment and support might confer beneficial effects.</p
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