245 research outputs found

    Isomeric di-c-glycosylflavones in fig (ficus carica l.)

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    Two isomeric C-glycosides of apigenin (ap ig en in -6-C -glucosyl-8-C -arab in o sid e (schaftoside), apigenin-6-C -arabinosyl-8-C -glucoside (isoschaftoside)) were isolated from leaves of Ficus carica with preparative HPLC. The glycosides were identified by UV-, ′H-N M R-, l3C-NMR-sp ectro scopy and FAB-MS. Their concentration in fruits and leaves were determined by gradient HPLC on reversed phase material. © 1985, Walter de Gruyter. All rights reserved

    Impact of antifungals producing rhizobacteria on the performance of Vigna radiata in the presence of arbuscular mycorrhizal fungi

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    Plant growth-promoting rhizobacteria (PGPR) that produce antifungal metabolites are potential threats for the arbuscular mycorrhizal (AM) fungi known for their beneficial symbiosis with plants that is crucially important for low-input sustainable agriculture. To address this issue, we used a compartmented container system where test plants, Vigna radiata, could only reach a separate nutrient-rich compartment indirectly via the hyphae of AM fungi associated with their roots. In this system, where plants depended on nutrient uptake via AM symbiosis, we explored the impact of various PGPR. Plants were inoculated with or without a consortium of four species of AM fungi (Glomus coronatum, Glomus etunicatum, Glomus constrictum, and Glomus intraradices), and one or more of the following PGPR strains: phenazine producing (P+) and phenazine-less mutant (P−), diacetylphloroglucinol (DAPG) producing (G+) and DAPG-less mutant (G−) strains of Pseudomonas fluorescens, and an unknown antifungal metabolite-producing Alcaligenes faecalis strain, SLHRE425 (D). PGPR exerted only a small if any effect on the performance of AM symbiosis. G+ enhanced AM root colonization and had positive effects on shoot growth and nitrogen content when added alone, but not in combination with P+. D negatively influenced AM root colonization, but did not affect nutrient acquisition. Principal component analysis of all treatments indicated correlation between root weight, shoot weight, and nutrient uptake by AM fungus. The results indicate that antifungal metabolites producing PGPR do not necessarily interfere with AM symbiosis and may even promote it thus carefully chosen combinations of such bioinoculants could lead to better plant growt

    Marine bacterial inhibitors from the sponge-derived fungus Aspergillus sp

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    Chromatographic separation of a crude extract obtained from the fungus Aspergillus sp., isolated from the Mediterranean sponge Tethya aurantium, yielded a new tryptophan derived alkaloid, 34(1-hydroxy-3-(2methylbut-3-en-2-y1)-2-oxoindolin-3-yl)methyl)-1-methyl-3,4-dihydrobenzo[e][1,41diazepine-2, 5-dione (1), and a new meroterpenoid, austalide R (2), together with three known compounds (3-5). The structures of the new compounds were unambiguously elucidated on the basis of extensive one and twodimensional NMR (1H, 13C, COSY, HMBC, and ROESY) and mass spectral analysis. Interestingly, the compounds exhibited antibacterial activity when tested against a panel of marine bacteria, with 1 selectively inhibiting Vibrio species and 2 showing a broad spectrum of activity. In contrast, no significant activity was observed against terrestrial bacterial strains and the murine cancer cell line L5178Y. (C) 2014 Elsevier Ltd. All rights reserved.Chemistry, OrganicSCI(E)[email protected]

    Promising Response of Olaparib in Patient With Germline

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    Gastric cancer ranks as the fifth leading cause of global cancer incidences, exhibiting varied prevalence influenced by geographical, ethnic, and lifestyle factors, as well a

    Perspectives on ageing, later life and ethniciy: Ageing research in ethnic minority contexts

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    This special issue focuses broadly upon questions and themes relating to the current conceptualisations, representations and use of ‘ethnicity’ (and ethnic minority experiences) within the field of social gerontology. An important aim of this special issue is to explore and address the issue of ‘otherness’ within the predominant existing frameworks for researching those who are ageing or considered aged, compounded by the particular constructions of their ethnicity and ethnic ‘difference’. The range of theoretical, methodological and empirical papers included in this collection provide some critical insights into particular facets of the current research agendas, cultural understandings and empirical focus of ethnic minority ageing research. The main emphasis is on highlighting the ways in which ethnic cultural homogeneity and ‘otherness’ is often assumed in research involving older people from ethnic minority backgrounds, and how wider societal inequalities are concomitantly (re)produced, within (and through) research itself – for example, based on narrowly defined research agendas and questions; the assumed age and/or ethnic differences of researchers vis-à-vis their older research participants; the workings of the formalised ethical procedures and frameworks; and the conceptual and theoretical frameworks employed in the formulation of research questions and interpretation of data. We examine and challenge here the simplistic categorisations and distinctions often made in gerontological research based around research participants’ ethnicity, age and ageing and assumed cultural differences. The papers presented in this collection reveal instead the actual complexity and fluidity of these concepts as well as the cultural dynamism and diversity of experiences within ethnic groups. Through an exploration of these issues, we address some of the gaps in existing knowledge and understandings as well as contribute to the newly emerging discussions surrounding the use of particular notions of ethnicity and ethnic minority ageing as these are being employed within the field of ageing studies.This special issue is one of the outcomes from the Economic and Social Research Council (ESRC) seminar series on ‘Ageing, Race and Ethnicity’ (project reference ES/J021547/1),held in the UK during 2012-2014. Open access for this editorial has been provided through the University of Nottingham open access funds

    Solution structure of the equine infectious anemia virus p9 protein: a rationalization of its different ALIX binding requirements compared to the analogous HIV-p6 protein

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    <p>Abstract</p> <p>Background</p> <p>The equine infection anemia virus (EIAV) p9 Gag protein contains the late (L-) domain required for efficient virus release of nascent virions from the cell membrane of infected cell.</p> <p>Results</p> <p>In the present study the p9 protein and N- and C-terminal fragments (residues 1-21 and 22-51, respectively) were chemically synthesized and used for structural analyses. Circular dichroism and <sup>1</sup>H-NMR spectroscopy provide the first molecular insight into the secondary structure and folding of this 51-amino acid protein under different solution conditions. Qualitative <sup>1</sup>H-chemical shift and NOE data indicate that in a pure aqueous environment p9 favors an unstructured state. In its most structured state under hydrophobic conditions, p9 adopts a stable helical structure within the C-terminus. Quantitative NOE data further revealed that this α-helix extends from Ser-27 to Ser-48, while the N-terminal residues remain unstructured. The structural elements identified for p9 differ substantially from that of the functional homologous HIV-1 p6 protein.</p> <p>Conclusions</p> <p>These structural differences are discussed in the context of the different types of L-domains regulating distinct cellular pathways in virus budding. EIAV p9 mediates virus release by recruiting the ALG2-interacting protein X (ALIX) via the YPDL-motif to the site of virus budding, the counterpart of the YPX<sub>n</sub>L-motif found in p6. However, p6 contains an additional PTAP L-domain that promotes HIV-1 release by binding to the tumor susceptibility gene 101 (Tsg101). The notion that structures found in p9 differ form that of p6 further support the idea that different mechanisms regulate binding of ALIX to primary versus secondary L-domains types.</p

    Pullularins E and F, two new peptides from the endophytic fungus Bionectria ochroleuca isolated from the mangrove plant Sonneratia caseolaris

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    Acknowledgements This project was supported by grants of the BMBF (to P.P.) and MOST (to W.L.). We wish to thank W.E.G. Müller (Johannes-Gutenberg-University, Mainz, Germany) for carrying out the cytotoxicity assay. A scholarship (Grant No. 10/6/117) granted and financed by the Egyptian Government (Ministry of High Education) to W.E. is gratefully acknowledged.Peer reviewedPublisher PD

    The Host-Pathogen interaction of human cyclophilin A and HIV-1 Vpr requires specific N-terminal and novel C-terminal domains

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    <p>Abstract</p> <p>Background</p> <p>Cyclophilin A (CypA) represents a potential key molecule in future antiretroviral therapy since inhibition of CypA suppresses human immunodeficiency virus type 1 (HIV-1) replication. CypA interacts with the virus proteins Capsid (CA) and Vpr, however, the mechanism through which CypA influences HIV-1 infectivity still remains unclear.</p> <p>Results</p> <p>Here the interaction of full-length HIV-1 Vpr with the host cellular factor CypA has been characterized and quantified by surface plasmon resonance spectroscopy. A C-terminal region of Vpr, comprising the 16 residues <sup>75</sup>GCRHSRIGVTRQRRAR<sup>90</sup>, with high binding affinity for CypA has been identified. This region of Vpr does not contain any proline residues but binds much more strongly to CypA than the previously characterized N-terminal binding domain of Vpr, and is thus the first protein binding domain to CypA described involving no proline residues. The fact that the mutant peptide Vpr<sup>75-90 </sup>R80A binds more weakly to CypA than the wild-type peptide confirms that Arg-80 is a key residue in the C-terminal binding domain. The N- and C-terminal binding regions of full-length Vpr bind cooperatively to CypA and have allowed a model of the complex to be created. The dissociation constant of full-length Vpr to CypA was determined to be approximately 320 nM, indicating that the binding may be stronger than that of the well characterized interaction of HIV-1 CA with CypA.</p> <p>Conclusions</p> <p>For the first time the interaction of full-length Vpr and CypA has been characterized and quantified. A non-proline-containing 16-residue region of C-terminal Vpr which binds specifically to CypA with similar high affinity as full-length Vpr has been identified. The fact that this is the first non-proline containing binding motif of any protein found to bind to CypA, changes the view on how CypA is able to interact with other proteins. It is interesting to note that several previously reported key functions of HIV-1 Vpr are associated with the identified N- and C-terminal binding domains of the protein to CypA.</p
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