Harmonia axyridis (Pallas) secondary metabolites quantification in relation with aposematism : Part II : Pyrazine quantification

Poster (2010, January)

The main objective of this study is to investigate the presence of links between chemical defences and warning signals presented by Harmonia axyridis (Pallas), the multicoloured Asian ladybird (Insects ... [more ▼]

The main objective of this study is to investigate the presence of links between chemical defences and warning signals presented by Harmonia axyridis (Pallas), the multicoloured Asian ladybird (Insects: Coleoptera: Coccinellidae). This second part describes an original quantification method for 2-isopropyl-3-methoxypyrazine (IPMP) by active sampling on thermally desorbed adsorbent (TD) coupled with GC-MS analysis. This highly odorous compound is supposed to be implicated in intra- and interspecific communication. In order to allow harmonine quantification (a defence alkaloid, see Part 1), this method avoid any hemolymph loses by the ladybird (Coccinellids can emit hemolymph when stressed). This method is non-lethal and applicable on one single insect. The quantification method has been validated from 37,5pg to 10 000 pg per adsorbent cartridge. On this range, there is no breakthrough and desorption is complete (>99.4%). At the LOQ (37.5pg/cartridge), the bias is of 20%, but rapidly decreased to less than 5% on the rest of the validated range (100 to 10 000 pg/cartridge). According to AOAC (2006) norm, this method is repeatable but not reproducible. The IPMP emission rate following a stress has been quantified on 80 H. axyridis grouped in four classes on basis of the morph type and the elytra hue. Males and females emission rates did not significantly differ. The mean emission rate is of 707 pg/4h with an extremely high standard deviation of 1766pg/4h due to a great individual variability and a strongly asymmetric distribution of the results. These results and those of the harmonine and colour analysis have been statistically analyzed in order to show potential correlations between these factors. It seems that elytra colour is linked with the insect IPMP emission rate. Individuals with a melanic red colour presented IPMP emission rate significantly lower than other studied colours. The harmonine content does not seem linked to the pyrazine emission rate. [less ▲]

Harmonic Trusses : the Search for Minimum Weight

(1998, February)

L'harmonisation des conditions individuelles de travail en cas de transfert conventionnel d'entreprise

in La cession d'entreprise: les aspects sociaux (2011)

Harmonisation des démarches de validation, est-elle possible ?

Conference (2003)

Harmonisation des stratégies de validation, utopie ou réalité ?

Conference (2004)

Harmonisation et construction

Article for general public (2009)

Harmonisation européenne des critères d'interprétation de l'Antibiogramme: Pourquoi, Quand, Difficultés et solutions

Scientific conference (2009, June 09)

Harmonisation européenne des critères d'interprétation de l'Antibiogramme: Pourquoi, Quand, Difficultés et solutions

Conference (2009, May 06)

Harmoniser le prix du livre importé de France. Impact d’un mark-up sur le consommateur, le secteur de la librairie et la diversité culturelle

Report (2010)

Harmonization of strategies for the validation of quantitative analytical procedures - A SFSTP proposal - part I

in Journal of Pharmaceutical & Biomedical Analysis (2004), 36(3), 579-586

This paper is the first part of a summary report of a new commission of the Societe Francaise des Sciences et Techniques Pharmaceutiques (SFSTP). The main objective of this commission was the ... [more ▼]

This paper is the first part of a summary report of a new commission of the Societe Francaise des Sciences et Techniques Pharmaceutiques (SFSTP). The main objective of this commission was the harmonization of approaches for the validation of quantitative analytical procedures. Indeed, the principle of the validation of theses procedures is today widely spread in all the domains of activities where measurements are made. Nevertheless. this simple question of acceptability or not of an analytical procedure for a given application, remains incompletely determined in several cases despite the various regulations relating to the good practices (GLP, GMP,...) and other documents of normative character (ISO, ICH. FDA,...). There are many official documents describing the criteria of validation to be tested, but they do not propose any experimental protocol and limit themselves most often to the general concepts. For those reasons, two previous SFSTP commissions elaborated validation guides to concretely help the industrial scientists in charge of drug development to apply those regulatory recommendations. If these two first guides widely contributed to the use and progress of analytical validations, they present, nevertheless, weaknesses regarding the conclusions of the performed statistical tests and the decisions to be made with respect to the acceptance limits defined by the use of an analytical procedure. The present paper proposes to review even the bases of the analytical validation for developing harmonized approach, by distinguishing notably the diagnosis rules and the decision rules. This latter rule is based on the use of the accuracy profile, uses the notion of total error and allows to simplify the approach of the validation of an analytical procedure while checking the associated risk to its usage. Thanks to this novel validation approach, it is possible to unambiguously demonstrate the fitness for purpose of a new method as stated in all regulatory documents. (C) 2004 Elsevier B.V. All rights reserved. [less ▲]