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Errouissi F.,Institute Superieur Des Science Biologiques Appliquees Of Tunis Issbat | Lumaret J.-P.,CNRS Center of Evolutionary and Functional Ecology
Medical and Veterinary Entomology | Year: 2010

A 2-year study was performed in two sites in southern France to assess the effect of ivermectin residues on the attractiveness of cattle dung to colonizing insects. Insect captures were compared between pitfall traps baited with dung from untreated cattle and dung from cattle that had been treated with a slow-release (SR) bolus of ivermectin. Cattle dung was collected at different times after treatment (4, 14, 42, 70 and 98 days). Excretion showed a plateau, with levels ranging between 0.688 μg and 1.123 μg ivermectin per gram of wet dung. Faecal residues affected insect captures at both sites. Effects were independent of the time dung was collected after treatment, except for one result subsequent to a severe drought during the baiting period. Ivermectin-contaminated dung showed a significant attractive effect, with increased captures regardless of the guild to which beetles belonged. This study demonstrates the attractiveness of ivermectin residues over a long period after the treatment of animals. It draws attention to the danger of widespread use of this endectocide-based SR bolus, which is attributable to the preferential attraction of insects to treated dung, which potentially puts at risk the survival of their offspring. © 2010 The Authors. Medical and Veterinary Entomology © 2010 The Royal Entomological Society.


Semmar N.,University of Burgundy | Semmar N.,Institute Superieur Des Science Biologiques Appliquees Of Tunis Issbat | Tomofumi M.,Kyushu University | Mrabet Y.,Institute Superieur Des Science Biologiques Appliquees Of Tunis Issbat | Lacaille-Dubois M.-A.,University of Burgundy
Helvetica Chimica Acta | Year: 2010

Two new tridesmosidic glycosides of (3β,6α,16β,20R,24S)-20, 24epoxycycloartane-3,6,16,25-tetrol (=cycloastragenol), armatosides I and II (1 and 2, resp.), were isolated from the roots of Astragalus armatus (Fabaceae) as well as the known bidesmosidic glycosides of cycloastragenol, trigonoside II (3) and trojanoside H (4). Their structures were elucidated as (3β,6α, 16β,20R,24S)-3-O-(2,3-di-O-acetyl-β-D-xylopyranosyl)-20, 24-epoxy-25-O-β-D-glucopyranosyl-6-O-β-D-xylopyranosylcycloartane-3,6, 16,25-tetrol (2). These structures were established by extensive NMR and MS analyses and by comparison with literature data. © 2010 Verlag Helvetica Chimica Acta AG.


Mrabet Y.,CNRS Institute of Chemistry | Semmar N.,Laboratoire Of Pharmacocinetique Et Toxicocinetique | Semmar N.,CNRS Institute of Chemistry | Semmar N.,Institute Superieur Des Science Biologiques Appliquees Of Tunis Issbat
Current Drug Metabolism | Year: 2010

Complexity of metabolic systems can be undertaken at different scales (metabolites, metabolic pathways, metabolic network map, biological population) and under different aspects (structural, functional, evolutive). To analyse such a complexity, metabolic systems need to be decomposed into different components according to different concepts. Four concepts are presented here consisting in considering metabolic systems as sets of metabolites, chemical reactions, metabolic pathways or successive processes. From a metabolomic dataset, such decompositions are performed using different mathematical methods including correlation, stoichiometric, ordination, classification, combinatorial and kinetic analyses. Correlation analysis detects and quantifies affinities/oppositions between metabolites. Stoichiometric analysis aims to identify the organisation of a metabolic network into different metabolic pathways on the hand, and to quantify/optimize metabolic flux distributions through the different chemical reactions of the system. Ordination and classification analyses help to identify different metabolic trends and their associated metabolites leading to highlight chemical polymorphism representing different variability poles of the metabolic system. Then, metabolic processes/correlations responsible for such a polymorphism can be extracted in silico by combining metabolic profiles representative of different metabolic trends according to a weighting bootstrap approach. Finally, evolution of metabolic processes in time can be analysed by different kinetic/dynamic modelling approaches. © 2010 Bentham Science Publishers Ltd.


Semmar N.,Laboratoire Of Pharmacologie Medicale Et Clinique | Semmar N.,Institute Superieur Des Science Biologiques Appliquees Of Tunis Issbat
Chemical Biology and Drug Design | Year: 2010

The flexibility of metabolic systems implies a high variability of metabolic profiles linked to different regulation ratios between metabolites. Such regulations are controlled by several interactive metabolic pathways resulting in multidirectional continuums of metabolic profiles. This article presents a new metabolomic approach helping to graphically analyse the flexibility of metabolic regulation systems. Its principle consists in extracting a metabolic backbone from iterative combinations of metabolic profiles representing different metabolic trends. The iterated combinations were performed on the basis of Scheffe matrix then averaged to calculate a response matrix of smoothed metabolic profiles. From such a smoothed matrix, a graphical analysis of relationships between metabolites highlighted different scale-dependent variation paths responsible for the observed metabolic trends. Such a flexibility favouring some metabolites at the expense of others was indirectly checked by a single kinetic approach by considering both the variation of maximal concentrations and the metabolic trends in time. This kinetic approach highlighted a succession of metabolic trends linked to the variation of maximal concentrations in time. Finally, a delayed regulation of a metabolite was highlighted both by the kinetic approach and by a dynamic application of the metabolomic approach. This new approach was illustrated on a dataset of blood concentrations of levodopa and its metabolites analysed in 34 patients at different times. © 2009 John Wiley & Sons A/S.


Jaouani A.,Tunis el Manar University | Jaouani A.,Institute Superieur Des Science Biologiques Appliquees Of Tunis Issbat | Gargano M.L.,University of Palermo | Ouali Z.,Tunis el Manar University | And 4 more authors.
Flora Mediterranea | Year: 2015

Pisolithus albus was recently collected for the first time in Tunisia. This ectomycorrhizal fungus is found associated with Eucalyptus occidentalis, a new symbiotic relationship, in the urban area of Tunis. The new record of this fungus on this tree permit to expand our knowledge on the ecology and distribution of P. albus in Tunisia. The finding is also important since this fungal symbiont has great potential in forestation efforts. Data on the morphology, molecular identification, distribution and, ecology for P. albus in Tunisia are presented for the first time.


PubMed | Institute Superieur Des Science Biologiques Appliquees Of Tunis Issbat
Type: Journal Article | Journal: Medical and veterinary entomology | Year: 2010

A 2-year study was performed in two sites in southern France to assess the effect of ivermectin residues on the attractiveness of cattle dung to colonizing insects. Insect captures were compared between pitfall traps baited with dung from untreated cattle and dung from cattle that had been treated with a slow-release (SR) bolus of ivermectin. Cattle dung was collected at different times after treatment (4, 14, 42, 70 and 98 days). Excretion showed a plateau, with levels ranging between 0.688 g and 1.123 g ivermectin per gram of wet dung. Faecal residues affected insect captures at both sites. Effects were independent of the time dung was collected after treatment, except for one result subsequent to a severe drought during the baiting period. Ivermectin-contaminated dung showed a significant attractive effect, with increased captures regardless of the guild to which beetles belonged. This study demonstrates the attractiveness of ivermectin residues over a long period after the treatment of animals. It draws attention to the danger of widespread use of this endectocide-based SR bolus, which is attributable to the preferential attraction of insects to treated dung, which potentially puts at risk the survival of their offspring.

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