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61.
Bengochea P Christiaens O Amor F Viñuela E Rougé P Medina P Smagghe G 《Pest management science》2012,68(7):976-985
BACKGROUND: The moulting accelerating compounds (MACs) or ecdysteroid agonists represent a selective group of insecticides acting upon binding to the ecdysteroid receptor (EcR) and leading to lethal premature moulting in larval stages and aborted reproduction in adults. Psyttalia concolor Szèpl. is a useful parasitic wasp attacking important tephritid pests such as the medfly and olive fruit fly. RESULTS: Contact and oral exposure in the laboratory of female parasitic wasps to the dibenzoylhydrazine‐based methoxyfenozide, tebufenozide and RH‐5849 did not provoke negative effects. No mortality and no reduction in beneficial capacity were observed. The ligand‐binding domain (LBD) of the EcR of P. concolor was sequenced, and a homology protein model was constructed which confirmed a cavity structure with 12 α‐helices, harbouring the natural insect moulting hormone 20‐hydroxyecdysone. However, a steric clash occurred for the MAC insecticides owing to a restricted extent of the ligand‐binding cavity of the PcLBD‐EcR, while they did dock well in that of susceptible insects. CONCLUSIONS: The insect toxicity assays demonstrated that MACs are selective for P. concolor. The modelling/docking experiments are indications that these insecticides do not bind with the LBD‐EcR of P. concolor and support the theory that they show no biological effects in the parasitic wasp. These data may help in explaining the compatible use of MACs together with parasitic wasps in IPM programmes. Copyright © 2012 Society of Chemical Industry 相似文献
62.
Friardi Ismed Françoise Lohézic-Le Dévéhat Olivier Delalande Sourisak Sinbandhit Amri Bakhtiar Joël Boustie 《Fitoterapia》2012
The diphenyl ether, lobarin (1) (syn. lobariol carboxylic acid) related to lobaric acid was isolated for the first time as a natural product along with five known compounds from Stereocaulon halei, a fruticose lichen collected in Indonesia. The structure of lobarin was elucidated by spectroscopic data analysis and its most stable conformers were determined by molecular mechanic dynamic calculations. A marked superoxide anion scavenging was found for compound 1 while no cytotoxicity on the B16 murine melanoma and HaCaT human keratinocyte cell lines was observed. 相似文献
63.
Anne Praud Olivier Gimenez Gina Zanella Nathalie Pozzi Valérie Antras Laurence Meyer Bruno Garin-Bastuji 《Tropical animal health and production》2013,45(4):931-933
Porcine brucellosis due to Brucella suis biovar 1 raises important issues for pig breeders in French Polynesia. In this region, the disease is enzootic, spreads silently and engenders economic losses in infected farms as well as sporadic human cases. While serological tests are essential in surveillance and control programmes of animal diseases, to date none of the available tests have been shown to be reliable enough to be used as a gold standard in routine individual diagnosis of porcine brucellosis. Few studies about the estimation of the sensitivity and the specificity of porcine brucellosis screening tests have been published, none of them dealing with French Polynesia. The studied population included 1,595 pigs from French Polynesia. Five tests were evaluated: Rose Bengal test, fluorescence polarisation assay, indirect ELISA, and two competitive ELISAs (C-ELISA). The sensitivity and the specificity of each test were estimated. C-ELISA2 was the most sensitive test (Se C-ELISA2?=?0.954 [0.889; 0.992] 95 % credibility interval (CrI)) while both C-ELISA and Rose Bengal test (RBT) were the most specific ones (Sp C-ELISA1?=?0.856 [0.806; 0.915] 95 % CrI; Sp C-ELISA2?=?0.849 [0.817; 0.879] 95 % CrI; Sp RBT?=?0.853 [0.812; 0.898] 95 % CrI). 相似文献
64.
Dianne Baunbk Nolwenn Trinkler Yoan Ferandin Olivier Lozach Poonsakdi Ploypradith Somsak Rucirawat Fumito Ishibashi Masatomo Iwao Laurent Meijer 《Marine drugs》2008,6(4):514-527
Lamellarins, a family of hexacyclic pyrrole alkaloids originally isolated from marine invertebrates, display promising anti-tumor activity. They induce apoptotic cell death through multi-target mechanisms, including inhibition of topoisomerase I, interaction with DNA and direct effects on mitochondria. We here report that lamellarins inhibit several protein kinases relevant to cancer such as cyclin-dependent kinases, dual-specificity tyrosine phosphorylation activated kinase 1A, casein kinase 1, glycogen synthase kinase-3 and PIM-1. A good correlation is observed between the effects of lamellarins on protein kinases and their action on cell death, suggesting that inhibition of specific kinases may contribute to the cytotoxicity of lamellarins. Structure/activity relationship suggests several paths for the optimization of lamellarins as kinase inhibitors. 相似文献
65.
Navarro L Dunoyer P Jay F Arnold B Dharmasiri N Estelle M Voinnet O Jones JD 《Science (New York, N.Y.)》2006,312(5772):436-439
Plants and animals activate defenses after perceiving pathogen-associated molecular patterns (PAMPs) such as bacterial flagellin. In Arabidopsis, perception of flagellin increases resistance to the bacterium Pseudomonas syringae, although the molecular mechanisms involved remain elusive. Here, we show that a flagellin-derived peptide induces a plant microRNA (miRNA) that negatively regulates messenger RNAs for the F-box auxin receptors TIR1, AFB2, and AFB3. Repression of auxin signaling restricts P. syringae growth, implicating auxin in disease susceptibility and miRNA-mediated suppression of auxin signaling in resistance. 相似文献
66.
Zuber MT Smith DE Phillips RJ Solomon SC Neumann GA Hauck SA Peale SJ Barnouin OS Head JW Johnson CL Lemoine FG Mazarico E Sun X Torrence MH Freed AM Klimczak C Margot JL Oberst J Perry ME McNutt RL Balcerski JA Michel N Talpe MJ Yang D 《Science (New York, N.Y.)》2012,336(6078):217-220
Laser altimetry by the MESSENGER spacecraft has yielded a topographic model of the northern hemisphere of Mercury. The dynamic range of elevations is considerably smaller than those of Mars or the Moon. The most prominent feature is an extensive lowland at high northern latitudes that hosts the volcanic northern plains. Within this lowland is a broad topographic rise that experienced uplift after plains emplacement. The interior of the 1500-km-diameter Caloris impact basin has been modified so that part of the basin floor now stands higher than the rim. The elevated portion of the floor of Caloris appears to be part of a quasi-linear rise that extends for approximately half the planetary circumference at mid-latitudes. Collectively, these features imply that long-wavelength changes to Mercury's topography occurred after the earliest phases of the planet's geological history. 相似文献
67.
Markó IE Stérin S Buisine O Mignani G Branlard P Tinant B Declercq JP 《Science (New York, N.Y.)》2002,298(5591):204-206
The hydrosilylation reaction enables the production of silicon polymers. Platinum-carbene complexes are reported that catalyze the hydrosilylation reaction of alkenes with remarkable efficiency and exquisite selectivity and avoid the formation of platinum colloids. By-products, typically encountered with previous catalytic systems, are suppressed with these platinum derivatives. 相似文献
68.
69.
Marilia Barreca Virginia Span Alessandra Montalbano Mercedes Cueto Ana R. Díaz Marrero Irem Deniz Ayegül Erdoan Lada Luki Bilela Corentin Moulin Elisabeth Taffin-de-Givenchy Filippo Spriano Giuseppe Perale Mohamed Mehiri Ana Rotter Olivier P. Thomas Paola Barraja Susana P. Gaudêncio Francesco Bertoni 《Marine drugs》2020,18(12)
The marine environment is a rich source of biologically active molecules for the treatment of human diseases, especially cancer. The adaptation to unique environmental conditions led marine organisms to evolve different pathways than their terrestrial counterparts, thus producing unique chemicals with a broad diversity and complexity. So far, more than 36,000 compounds have been isolated from marine micro- and macro-organisms including but not limited to fungi, bacteria, microalgae, macroalgae, sponges, corals, mollusks and tunicates, with hundreds of new marine natural products (MNPs) being discovered every year. Marine-based pharmaceuticals have started to impact modern pharmacology and different anti-cancer drugs derived from marine compounds have been approved for clinical use, such as: cytarabine, vidarabine, nelarabine (prodrug of ara-G), fludarabine phosphate (pro-drug of ara-A), trabectedin, eribulin mesylate, brentuximab vedotin, polatuzumab vedotin, enfortumab vedotin, belantamab mafodotin, plitidepsin, and lurbinectedin. This review focuses on the bioactive molecules derived from the marine environment with anticancer activity, discussing their families, origin, structural features and therapeutic use. 相似文献
70.
Daniel Rodrigues Celso Alves André Horta Susete Pinteus Joana Silva Gérald Culioli Olivier P. Thomas Rui Pedrosa 《Marine drugs》2015,13(2):713-726
Cancer and infectious diseases continue to be a major public health problem, and new drugs are necessary. As marine organisms are well known to provide a wide range of original compounds, the aim of this study was to investigate the bioactivity of the main constituents of the cosmopolitan red alga, Sphaerococcus coronopifolius. The structure of several bromoditerpenes was determined by extensive spectroscopic analysis and comparison with literature data. Five molecules were isolated and characterized which include a new brominated diterpene belonging to the rare dactylomelane family and named sphaerodactylomelol (1), along with four already known sphaerane bromoditerpenes (2–5). Antitumor activity was assessed by cytotoxicity and anti-proliferative assays on an in vitro model of human hepatocellular carcinoma (HepG-2 cells). Antimicrobial activity was evaluated against four pathogenic microorganisms: Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Candida albicans. Compound 4 exhibited the highest antimicrobial activity against S. aureus (IC50 6.35 µM) and compound 5 the highest anti-proliferative activity on HepG-2 cells (IC50 42.9 µM). The new diterpene, sphaerodactylomelol (1), induced inhibition of cell proliferation (IC50 280 µM) and cytotoxicity (IC50 720 µM) on HepG-2 cells and showed antimicrobial activity against S. aureus (IC50 96.3 µM). 相似文献