78 research outputs found

    Transmission congĂ©nitale de la brucellose bovine d’une gĂ©nĂ©ration Ă  l’autre

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    Plommet M., Renoux G., Philippon Alain, Gestin J., Fenster-Bank R. Transmission congĂ©nitale de la brucellose bovine d’une gĂ©nĂ©ration Ă  l’autre. In: Bulletin de l'AcadĂ©mie VĂ©tĂ©rinaire de France tome 124 n°1, 1971. pp. 53-59

    The double [3+2] photocycloaddition reaction

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    One of a synthetic organic chemists‟ greatest challenges is to create step-efficient routes toward compounds with high molecular complexity. Therefore, reactions such as the meta photocycloaddition of an olefin to a benzene derivative, which provide more than one bond in a single step are of significant importance. It this remarkable reaction three new σ bonds, three new rings and up to six new stereocenters are formed simultaneously. Additional complexity can be added by tethering the two reacting partners together and this form of the reaction has found many uses in natural product synthesis. In this work a remarkable double [3+2] photocycloaddition reaction is reported that results in the formation of a complex cis, cis, cis, trans-[5, 5, 5, 5] fenestrane derivative from a simple flat aromatic acetal with two branching alkenes. During this dramatic transformation four carboncarbon bonds, five new rings and seven new stereocenters are created in a single one-pot process using only UV light. The reaction occurs in a sequential manner from the linear meta photocycloadduct, via a secondary [3+2] addition of the alkene across the cyclopropane of the adduct. In addition, an angular meta photocycloadduct also produced in the initial addition step, undergoes an alternative fragmentation-translocation photoreaction to afford a silphinene-like angular tricyclic compound. In this work the investigation of this newly discovered process is discussed via the synthesis and subsequent irradiation of a series of photosubstrates containing different functional groups in the arene-alkene tether. In addition, attempts toward the synthesis of alternative structures using the same double [3+2] photocycloaddition are reported

    The Ocular Conjunctiva as a Mucosal Immunization Route: A Profile of the Immune Response to the Model Antigen Tetanus Toxoid

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    Background: In a quest for a needle-free vaccine administration strategy, we evaluated the ocular conjunctiva as an alternative mucosal immunization route by profiling and comparing the local and systemic immune responses to the subcutaneous or conjunctival administration of tetanus toxoid (TTd), a model antigen. Materials and methods: BALB/c and C57BL/6 mice were immunized either subcutaneously with TTd alone or via the conjunctiva with TTd alone, TTd mixed with 2% glycerol or TTd with merthiolate-inactivated whole-cell B. pertussis (wBP) as adjuvants. Mice were immunized on days 0, 7 and 14 via both routes, and an evaluation of the local and systemic immune responses was performed two weeks after the last immunization. Four weeks after the last immunization, the mice were challenged with a lethal dose (2 x LD50) of tetanus toxin. Results: The conjunctival application of TTd in BALB/c mice induced TTd-specific secretory IgA production and skewed the TTd-specific immune response toward a Th1/Th17 profile, as determined by the stimulation of IFN gamma and IL-17A secretion and/or the concurrent pronounced reduction of IL-4 secretion, irrespective of the adjuvant. In conjunctivaly immunized C57BL/6 mice, only TTd administered with wBP promoted the establishment of a mixed Th1/Th17 TTd-specific immune response, whereas TTd alone or TTd in conjunction with glycerol initiated a dominant Th1 response against TTd. Immunization via the conjunctiva with TTd plus wBP adjuvant resulted in a 33% survival rate of challenged mice compared to a 0% survival rate in non-immunized animals (p lt 0.05). Conclusion: Conjunctival immunization with TTd alone or with various adjuvants induced TTd-specific local and systemic immune responses, predominantly of the Th1 type. The strongest immune responses developed in mice that received TTd together with wBP, which implies that this alternative route might tailor the immune response to fight intracellular bacteria or viruses more effectively

    Divalent and Multivalent Activation in Phosphate Triesters: A Versatile Method for the Synthesis of Advanced Polyol Synthons

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    This is the peer reviewed version of the following article: Thomas, C. D., McParland, J. P. and Hanson, P. R. (2009), Divalent and Multivalent Activation in Phosphate Triesters: A Versatile Method for the Synthesis of Advanced Polyol Synthons. Eur. J. Org. Chem., 2009: 5487–5500. doi:10.1002/ejoc.200900560, which has been published in final form at http://doi.org/10.1002/ejoc.200900560. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.The construction of mono- and bicyclic phosphate trimesters possessing divalent and multivalent activation and their subsequent use in the production of advanced polyol synthons is presented. The method highlights efforts to employ phosphate tethers as removable, functionally active tethers capable of multipositional activation and their subsequent role as leaving groups in selective cleavage reactions. The development of phosphate tethers represents an integrated platform for a new and versatile tether for natural product synthesis and sheds light on new approaches to the facile construction of small molecules

    Allergie diagnosis of brucellosis

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    A fifty years fight against sheep and goats brucellosis First al all, the author analyses the history of the fight engaged since 1908, when brucellosis first appeared in France. He explains what kind of results were obtained, there and elsewhere ; he also mentions the numerous failures and their reasons. Afterwards he studies the possibilities of success with several new methods. Finally, he makes some proposale for a complete and preventive information about all abortive diseases.Un nouvel allergĂšne, la brucelline I.N.R.A., est proposĂ© pour le dĂ©pistage de la brucellose par l'Ă©preuve d’hypersensibilitĂ© cutanĂ©e de type retardĂ©. L’injection de cet allergĂšne, facile et sans danger pour l'animal, ne provoque pas la formation d'anticorps dĂ©tectables par les Ă©preuves habituelles de dĂ©pistage sĂ©rologique, ni la sensibilisation de l'organisme. Le dĂ©pistage ultĂ©rieur, par Ă©preuves allergiques ou sĂ©rologiques, n’est donc pas perturbĂ© par une premiĂšre Ă©preuve. Le test allergique est proposĂ© pour amĂ©liorer le diagnostic de la brucellose chez les bovins et les petits ruminants, et pour Ă©viter des prises de sang fastidieuses, en particulier dans les troupeaux de petits ruminants situĂ©s dans des zones rĂ©putĂ©es indemnes.Fenster-Bank R. Le diagnostic allergique de la brucellose. In: Bulletin de l'AcadĂ©mie VĂ©tĂ©rinaire de France tome 135 n°1, 1982. pp. 47-52
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