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Summary With the aim of visualizing myocardial angiotensin II receptors (AT1 subtypes), [tetrazoyl-11C]2-n-butyl-1-[(2′-(1Htetrazol-5-yl)-1, 1′-biphenyl-4-yl)methyl]-4-spirocyclo-pentane-2-imidazoline-5-one ([tetrazoyl-11C]irbesartan (SR47436/BMS-186295)) 11 was synthesized in one pot in four steps from [11C]hydrogen cyanide. The labelling process which yielded [tetrazoyl-11 C]irbesartan is described in detail and could be applied to the labelling of other ligands which possess the (1H-tetrazol-5-yl) moiety. Positron emission tomography (PET) studies were performed in dogs. Heart, lung and blood time-activity curves did not change. Therefore this new radioligand is not suitable for studying myocardial angiotensin II receptors with PET.

Radioligands that specifically target dopamine uptake sites can provide a means of determining dopamine fiber loss at intrastriatal mesencephalic grafts in Parkinsonian patients, using Positron Emission Tomography (PET). The BTCP derivative, 1-[1-(2-benzo(b)thiophenyl)cyclohexyl]-4-(2-hydroxyethyl)-piperazine, shows in vitro high affinity and selectivity for the dopamine transporter. To evaluate the potential of such a compound as a potential dopaminergic PET tracer the positron-emitting analogues, 1-[1-(2-benzo (b)thiophenyl)cyclohexyl]-4-(2-[ 18 F]fluoroethyl)-piperazine and 1-[1-(2-benzo(b)thiophenyl)cyclohexyl]-4-[ 11 C]methylpiperazine, were synthesized. Radiofluorination was carried out by the reaction of 1-[1-(2-benzo(b)thiophenyl)cyclohexyl]-4-(2-chloroethyl)-piperazine with cyclotron-produced n.c.a. 18 F-(half life 109.9 min) obtained by the (p,n) reaction on 18 O-enriched water. Labelling with carbon-11 (half life 20.4 min) was achieved by 11 C methylation of 1-[1-(2-benzo(b)thiophenyl)cyclohexyl]-piperazine with [ 11 C]methyl iodide. After intravenous administration to rats these two compounds enter the brain, but despite their high in vitro affinity they display a high non specific binding in vivo which greatly limits their use as PET radioligands.

Radiosynthesis of [cyano- 11 C]benzonitriles, [carboxyl- 11 C]benzoic acids, [carbonyl- 11 C]benzamides and [tetrazoyl- 11 C]5-biphenyl-1H-tetrazoles are described. [Cyano- 11 C]benzonitriles were prepared using the Rosenmund-von Braun reaction in one step from [ 11 C]hydrogen cyanide via [ 11 C]copper(I) cyanide in 2 min. [Carboxyl- 11 C]benzoic acids and [carbonyl- 11 C]benzamides were prepared from [cyano- 11 C]benzonitrile-complex using basic hydrogen peroxide for 3 min in N , N -dimethylformamide at 180 and 80°C, respectively. [Tetrazoyl- 11 C]5-biphenyl-1H-tetrazoles were obtained from [cyano- 11 C]benzonitrile-complexes in 7 min by cyclization with trimethyltin azide followed by acid hydrolysis at 180°C. These labelled compounds were obtained in a one-pot procedure with good average specific radioactivities [500 mCi/μmol (18.5 GBq/μmol) at the end of synthesis] and in satisfactory average radiochemical yields (24–69%) at 40 min from the end of radionuclide production. This new radioactive precursor. [ 11 C]copper(I) cyanide, should give access to new 11 C-labelled ligands for positron emission tomography.

ENJEUX ET EVALUATION DES EMISSIONS GAZEUSES DANS LES ELEVAGES DE VOLAILLES. 10èmes Journées de la Recherche Avicoles et Palmipèdes à Foie Gras

Measuring the emissions of thousands of animal houses is needed to obtain representative emission factors and relevant categories of animal farms for emission inventories. This scale is also necessary to develop a comprehensive understanding of all facotrs that influence ammonia and greenhouse gas emissions at the farm scale. A robust and low-cost method was developed in France to measure emissions from poultry, bovine and swine houses. A database and associated software is presented here that helps to apply this method to a large number of houses, while protecting the data when the database is used by different companies or institutions. It is based on freeware: an Ubuntu system, OpenOffice for testing equations, PostgreSQL and PgAdmin for database management with “user-only” or “project-only” restricted access to data, and C++ with CodeBlocks and wxWidgets for the calculation and interface modules developed. As for typical Ubuntu software, all messages in the interfaces developed can be translated into several languages using PoEdit. All systems, software and data can be stored on a bootable USB flash drive or SD card with at least two partitions, one for the system (FAT32) compressed into a squashfs file, and one for the modified files (EXT2). The data are divided into three categories: national references (e.g. manure composition), farm references (e.g. specific house characteristics), and observations (e.g. gas concentrations). Training is recommended to begin using the software more quickly. Further development is required to adapt this tool to monitor the results of mitigation strategies and improve their efficiency.

In the ten years before the EMILI 2012 symposium, g aseous losses from animal farms became increasingly important in the m edia. The paradox of this tendency was the great number of publications, scientific or not, even though the emissions of most animal farms had never been measured. Therefor e, the development of reference tools to measure greenhouse gas and ammonia emissio ns was important. Such tools allow recognition and remuneration of the best pract ices and equipment. Accordingly, ADEME funded an international project associating sev eral research and development organizations involved with the animal production c hain. The project proposed an initial set of 18 procedures to measure ammonia and greenho use gas emissions from animal houses and manure stores. These were adapted to the diversity of animal farms found throughout the world. Some methods were compared duri ng a “building” and a “liquid manure” experiment. Results showed a high difference among methods (ca. 80%), much higher than the estimated uncertainty. Associat ing independent emission measurements, together with a mass balance of the sy stem, is necessary for the reliability of further results. However, previously p ublished references lack uncertainty estimates of measurements that conform to GUM 2008. I n the coming years, this is one of the major concerns for measuring emission factor s. Uncertainty estimates should depend on the measurand (temporal: hourly, per batc h, yearly; spatial: animal, house, national) and include the uncertainties associated with system representativity and temporal interpolation.

L’objectif de cette étude est, d’une part, d’estimer les impacts environnementaux d’un système représentatif des pratiques de production nationale de lapin de chair, et d’autre part, d’évaluer les conséquences d’une restriction alimentaire pratiquée chez le lapin après le sevrage à l’aide de la méthode d’Analyse du Cycle de Vie. La restriction de l’ingestion entraîne une baisse du potentiel de réchauffement climatique (- 9 %), des potentiels d’eutrophisation (- 11 %) et d’acidification (- 12 %) et de l’occupation des surfaces agricoles (- 10 %). Elle montre également que l’alimentation des animaux et les effluents sont les postes qui contribuent le plus aux différents impacts environnementaux. L’étape d’engraissement contribue également plus que les étapes de maternité ou d’abattage. Ces résultats offrent des perspectives de travail pour proposer des stratégies possibles d’amélioration.

The BTCP derivative 1-11-(2-benzo[b]thiophenyl) cyclohexyl]-4-(2-hydroxyethyl) piperazine 2 showed, in vitro, high affinity and selectivity for the Dopamine transporter. In order to evaluate the potential of such a compound as an imaging tool for studying the dopaminergic system by Positron Emission Tomography (PET) the cold fluoroethyl BTCP piperazine 6 was synthesized. After checking the biological activity of the cold compound 6, the [ 18 F] analogue 7 was synthesized. The radiosynthesis was carried out by the nucleophilic substitution of 1-[1-(2-benzo[b]thiophenyl) cyclohexyl]-4-(2-chloroethyl) piperazine 5 with cyclotron-produced n.c.a. 18 F - , obtained by the (p,n) reaction on 18 O enriched water.

National audience; La déforestation pour la mise en place de prairies constitue une perturbation majeure et brutale en zone tropicale avec des enjeux importants sur les impacts et services environnementaux liés aux écosystèmes herbagers. C’est le cas en Guyane française et plus généralement en Amazonie où le développement de l’élevage doit se raisonner dans le cadre de la protection du patrimoine forestier et des mesures actuelles d'atténuation de GES (gaz à effet de serre). L’étude analyse la dynamique temporelle du carbone (C) dans les sols d’une chronoséquence composée de 25 prairies âgées de 6 mois à 41 ans issues de la déforestation et de 6 sites de forêt témoins sur des sols ferralitiques en Guyane. L’analyse isotopique du C (δ13C) a été utilisée pour déterminer l’origine du C des sols des prairies (issu de la forêt ou des graminées de la prairie). Une vingtaine d’année après leur mise en place, les prairies stockent autant de C que les sols forestiers d’origine (de 72 à 148 t C/ha, 100 t en moyenne), valeurs dépassés par certaines prairies de plus de 30 ans avec des valeurs maximales comprises entre 140 et 203 t C/ha. Les mesures isotopiques montrent que le C forestier est progressivement remplacé par le C issu des prairies au cours du temps. La caractérisation du C par son degré de dégradation dans le sol montre que le C est essentiellement stocké sous forme récalcitrante.

National audience; La déforestation pour la mise en place de prairies constitue une perturbation majeure et brutale en zone tropicale avec des enjeux importants sur les impacts et services environnementaux liés aux écosystèmes herbagers. C’est le cas en Guyane française et plus généralement en Amazonie où le développement de l’élevage doit se raisonner dans le cadre de la protection du patrimoine forestier et des mesures actuelles d'atténuation de GES (gaz à effet de serre). L’étude analyse la dynamique temporelle du carbone (C) dans les sols d’une chronoséquence composée de 25 prairies âgées de 6 mois à 41 ans issues de la déforestation et de 6 sites de forêt témoins sur des sols ferralitiques en Guyane. L’analyse isotopique du C (δ13C) a été utilisée pour déterminer l’origine du C des sols des prairies (issu de la forêt ou des graminées de la prairie). Une vingtaine d’année après leur mise en place, les prairies stockent autant de C que les sols forestiers d’origine (de 72 à 148 t C/ha, 100 t en moyenne), valeurs dépassés par certaines prairies de plus de 30 ans avec des valeurs maximales comprises entre 140 et 203 t C/ha. Les mesures isotopiques montrent que le C forestier est progressivement remplacé par le C issu des prairies au cours du temps. La caractérisation du C par son degré de dégradation dans le sol montre que le C est essentiellement stocké sous forme récalcitrante.

With the aim of reducing the environmental impacts of poultry feed, a database of the impacts of feed components destined for formulation was constructed using the Life Cycle Assessment (LCA) method. We used linear programming to create least cost feed formulas for fast-growing broiler (FGB), slow-growing broiler (SGB, i.e. quality label), laying hen and for three contrasting feed-cost situations (January 2006, December 2007 and March 2009). We focused on Eutrophication Potential (EP, a regional impact) and Climate Change (CC, a global impact) which were constraints to formulate low-impact poultry feed. The effects of using these constraints on feed cost and the use of feed components were investigated for a feed production plant in Bretagne (western France). Environmental impacts of poultry feed increased with the energy and protein content of the formula and were affected by the relative costs of feed components. FGB formulas had the highest impacts, followed by formulas for SGB and laying hens. The search for a minimum level of EP and CC of the formula decreased its impacts by 1-8% and by 1-12% respectively, and increased its cost by 2-8%, depending on the type of feed and the feed-cost situation. Impact reduction was obtained by partial substitution of soybean meal and cereals by rapeseed meal, grain legumes and co-products (wheat bran, gluten). Furthermore, 70% of the potential reduction of the EP and CC impacts could be obtained at a modest (0.5-4%) increase in the cost of the formulas. Some other ways to reduce feed impacts were explored, such as taking into account the geographic origin of maize crops and adopting a modified regulatory constraint for SGB formulas. It is important to continue this study by taking into account the whole life cycle of poultry production. (C) 2011 Elsevier Ltd. All rights reserved.

National audience; Dans un contexte de forte préoccupation concernant le changement climatique et l’impact des activités humaines sur l’environnement, les instituts techniques agricoles animaux (Institut de l’élevage, IFIP, ITAVI) et végétaux (ARVALIS Institut du Végétal, CETIOM, ITB) ont souhaité fournir les moyens méthodologiques pour préciser la contribution de l’agriculture à l’effet de serre. Le guide méthodologique GES’TIM a ainsi été élaboré pour constituer la référence en matière d’estimation des impacts des activités agricoles sur l’effet de serre (quantification des émissions gazeuses du cheptel, du sol, consommations d’énergies, intrants et compensation par le stockage de carbone). L’objectif est de proposer un vocabulaire et un cadre méthodologique homogénéisés, avec des facteurs d’émissions représentatifs des filières de production agricole françaises. La volonté est de diffuser ce référentiel afin de créer des repères pour les décideurs, les techniciens et les agriculteurs, en vue de raisonner les itinéraires techniques face au défi du changement climatique. GES’TIM est une production de l’action Casdar « Gaz à effet de serre et stockage de carbone en exploitations agricoles » (2007 -2009).

Summary With the aim of visualizing myocardial angiotensin II receptors (AT1 subtypes), [tetrazoyl-11C]2-n-butyl-1-[(2′-(1Htetrazol-5-yl)-1, 1′-biphenyl-4-yl)methyl]-4-spirocyclo-pentane-2-imidazoline-5-one ([tetrazoyl-11C]irbesartan (SR47436/BMS-186295)) 11 was synthesized in one pot in four steps from [11C]hydrogen cyanide. The labelling process which yielded [tetrazoyl-11 C]irbesartan is described in detail and could be applied to the labelling of other ligands which possess the (1H-tetrazol-5-yl) moiety. Positron emission tomography (PET) studies were performed in dogs. Heart, lung and blood time-activity curves did not change. Therefore this new radioligand is not suitable for studying myocardial angiotensin II receptors with PET.

National audience

Substitution of the chlorine atom by a radio-iodine in position 5 in the zacopride molecule yielded [125I]iodo-zacopride that bound with high affinity (Kd = 4.3 nM) to 5-HT3 receptors in the rat central nervous system. Assays with membranes from the posterior (mainly entorhinal) cortex confirmed that the pharmacological properties and regional distribution of [125I]iodo-zacopride-specific binding sites were identical with those of 5-HT3 sites labelled by the reference radioligand [3H]zacopride. Autoradiographic investigations for the visualization and quantification of 5-HT3 receptors yielded similar results with both radioligands, but autoradiograms could be obtained after only 1-3 days of exposure of sections labelled with [125I]iodo-zacopride, instead of 4-6 months using [3H]zacopride. The highest density of 5-HT3 sites was found in the nucleus tractus solitarius followed by, in decreasing order, the dorsal motor nucleus of the vagus nerve, the superficial layers of the dorsal horn in the spinal cord, the nucleus of the spinal tract of the trigeminal nerve, and the area postrema. Significant labelling of 5-HT3 receptors was also observed in limbic areas (amygdala, hippocampus, frontal and entorhinal cortex), and to a much lower extent in the dorsal raphe nucleus, striatum, and substantia nigra. These multiple locations further support the idea that 5-HT3 receptors are probably involved in several 5-HT-mediated functions in the central nervous system.

In an attempt to develop a specific probe of serotonin 5-HT3 receptors, various methods have been investigated to synthesize a radioiodinated derivative of the potent 5-HT3 antagonist zacopride. The direct iodination of 5-dechloro-zacopride 2 was performed using NaI in the presence of either chloramine T or iodo-beads. Irreproducible results or/and low yields were obtained by these methods. A third approach using a less oxidative medium allowed the synthesis of iodo-zacopride 4 from 2 with N-iodo-succinimide or with NaI and N-chlorosuccinimide. Using this third condition, high yield was obtained (49%). However, the radioiodinated compound was contaminated by some “cold” zacopride also formed during the reaction. A two step synthesis was successful to eliminate “cold” zacopride but in lower yield (2-10%). Thus, 4-amino-2-methoxy-benzoate 5 was iodinated and then coupled with 3-aminoquinuclidine 8 to give 5-iodo-zacopride 4. Radioactive synthesis was carried out in the same condition to give 5-[1251]-iodo-zacopride 1 with a yield of 98%. The two enantiomers R-and S-5-[1251]-iodo-zacopride were synthesized by direct iodination.

National audience

After verification of the biological activity of 3-iodo-PCP by binding studies to the N-methyl D-aspartate gated channel, 3-[125I]iodo-PCP was prepared by reaction of sodium iodide with a triazene precursor. The radiochemical yield was optimized and after HPLC purification, 3-[125I]iodo-PCP was obtained with a high radiochemical purity.

The synthesis of a photosensitive iodinated derivative of tetrabenazine, which should be able to lead to the identification of the vesicular catecholamine transporter of adrenal medulla by photoaffinity, is described in detail. The biological activity of this iodinated ligand was found to be significantly lower than that of non iodinated ligands.

The [3',5']-ditritio-alpha-fluoromethyl-tyrosine 4 (specific activity 15.0 Ci/mmol) has been synthesized and used as a radioactive probe for rat neuronal tyrosine hydroxylase (TH). The route of synthesis for the preparation of 3 and 4 allowed us to not only introduce a fluorine atom into 3/4 using an inorganic source of fluorine (CsF), but also to take advantage of the high-yielding cyclization of (alpha,beta)-acetamido alcohols mediated by diethylaminosulfur trifluoride (DAST) to give the corresponding oxazolines. The distribution and metabolism of 4 have been studied in control conditions within the rat locus caeruleus (LC). Intracisternal injection of 20 microCi of 4 was followed by a rapid disappearance of 4 (t1/2 = 1.5 h) and by a specific accumulation of radioactivity into the LC anatomical limits. This was investigated each 140 microns along the caudo-rostral axis of the noradrenergic nucleus. In each anatomical interval, its distribution correlated nicely with already described caudo-rostral distribution of TH in noradrenergic cells. Thus, 4 may provide a reliable measure of TH activity in such catecholamine structures.

In an attempt to visualize in vivo the dopamine transporter and evaluate its potential as an imaging tool for monitoring dopamine fiber degeneration by positron emission tomography, the 18F-positron-emitting analogue of 3-fluoromethyl-1-[1-(2-benzothienyl)-cyclohexyl]-piperidine, [18F]BTCP, was synthetized and tested in a primate model of hemiparkinsonism. [18F]BTCP was obtained from cyclotron-produced n.c.a. [18F]fluoride (110min half-life) and by nucleophilic substitution from 3-bromomethyl-BTCP with a radiochemical yield of 6% (decay-corrected). After intravenous injection, the cerebral distribution of the radioactivity was observed mainly in cortical areas and cerebral structures enriched in catecholamine reuptake sites such as the caudate-putamen complex and the thalamus. The binding ratio, defined with respect to the cerebellum (taken as a region of non-specific binding), was highest in the thalamus (1.42), intermediate in the putamen (1.36) and lowest in the caudate nucleus (1.17), suggesting that some specific binding occurs in these regions. After saturation of dopamine and norepinephrine transporters by nomifensine, the binding ratio in the thalamus, putamen and caudate nucleus striatum remained essentially unchanged in the non-lesioned hemisphere. When comparing binding ratios between the intact and the dopamine-denervated striatum, there was a modest loss of binding in the denervated striatum, suggesting that degeneration of dopaminergic fibers could be detected using 3-[18F]fluoromethyl-BTCP. However due to a high non-specific binding in vivo, the interest of 3-[18F]fluoromethyl-BTCP to image the dopamine reuptake system in vivo appears rather limited.

International audience; The binding properties of the 125I-labeled phencyclidine derivative N-[1-(3-[125I]iodophenyl)cyclohexyl]piperidine (3-[125I]iodo-PCP), a new ligand of the N-methyl-D-aspartate (NMDA)-gated ionic channel, were investigated. Association and dissociation kinetic curves of 3-[125I]iodo-PCP with rat brain homogenates were well described by two components. About 32% of the binding was of fast association and fast dissociation, and the remaining binding was of slow association and slow dissociation. Saturation curves of 3-[125I]iodo-PCP also were well described using two binding sites: one of a high affinity (KDH = 15.8 +/- 2.3 nM) and the other of a low affinity (KDL = 250 +/- 40 nM). 3-Iodo-PCP inhibited the binding of 3-[125I]iodo-PCP with inhibition curves that were well fitted by a two-site model. The binding constants (KiH, BmaxH; KiL, BmaxL) so obtained were close to those obtained in saturation experiments. Ligands of NMDA-gated ionic channels also inhibited the binding of 3-[125I]iodo-PCP with two constants, KiH and KiL. There was a very good correlation (r = 0.987) between the affinities of these ligands to bind to NMDA-gated ionic channels and their potencies to inhibit the binding of 3-[125I]iodo-PCP with a high affinity. Moreover, the regional distribution of the high-affinity binding of 3-[125I]-iodo-PCP paralleled that of tritiated N-[1-(2-thienyl)cyclohexyl]piperidine ([3H]TCP). In contrast to that of [3H] TCP, the binding of 3-[125I]iodo-PCP to well-washed rat brain membranes was fast and insensitive to glutamate and glycine.(ABSTRACT TRUNCATED AT 250 WORDS)

There are only a few ligands available for labelling brain receptors simply because in vivo binding requires more severe experimental conditions than in vitro binding. We now describe the in vivo binding properties of [3H]RP 62203, a new potent and selective 5-HT2 antagonist. After intravenous injection into rats, [3H]RP 62203 accumulated predominantly in brain regions containing 5-HT2 receptors, with a frontal cortex/cerebellum ratio of 6 to 7. A good correlation was obtained between the regional distribution of [3H]RP 62203 in the brain and the density of 5-HT2 receptors measured in vitro. In vivo binding of [3H] RP 62203 was saturable in the frontal cortex but not in the cerebellum. The Bmax in the frontal cortex was equal to 42.5 fmol/mg, thus in the same range as was found in vitro. The 5-HT2 selectivity was ascertained by displacement (prevention) experiments; 5-HT2 antagonists or the agonist 2,5-dimethoxy- 4-iodophenylisopropylamine could prevent specific labelling of [3H]RP 62203 only in brain regions containing 5-HT2 receptors. Interestingly, the radioactivity remaining in various brain regions after displacement with pipamperone corresponded exactly to that measured in the cerebellum, with or without pipamperone. In conclusion, [3H]RP 62203 possesses striking properties of in vivo binding which make it a suitable candidate for examining 5-HT2 receptors in human brain by positron emission tomography scanning.

Substitution of the chlorine atom by a radio-iodine in position 5 in the zacopride molecule yielded [125I]iodo-zacopride that bound with high affinity (Kd = 4.3 nM) to 5-HT3 receptors in the rat central nervous system. Assays with membranes from the posterior (mainly entorhinal) cortex confirmed that the pharmacological properties and regional distribution of [125I]iodo-zacopride-specific binding sites were identical with those of 5-HT3 sites labelled by the reference radioligand [3H]zacopride. Autoradiographic investigations for the visualization and quantification of 5-HT3 receptors yielded similar results with both radioligands, but autoradiograms could be obtained after only 1-3 days of exposure of sections labelled with [125I]iodo-zacopride, instead of 4-6 months using [3H]zacopride. The highest density of 5-HT3 sites was found in the nucleus tractus solitarius followed by, in decreasing order, the dorsal motor nucleus of the vagus nerve, the superficial layers of the dorsal horn in the spinal cord, the nucleus of the spinal tract of the trigeminal nerve, and the area postrema. Significant labelling of 5-HT3 receptors was also observed in limbic areas (amygdala, hippocampus, frontal and entorhinal cortex), and to a much lower extent in the dorsal raphe nucleus, striatum, and substantia nigra. These multiple locations further support the idea that 5-HT3 receptors are probably involved in several 5-HT-mediated functions in the central nervous system.

This paper describes the synthesis and the pharmacological characteristics of the first radioiodinated ligand of central 5-HT3 receptors: [125I]iodo-zacopride. Specific sites having a high affinity (Kd = 4.3 nM) for [125I]iodo-zacopride have been found in membranes from the rat entorhinal cortex. In addition, a highly significant correlation (r = 0.995) existed between the Ki of several 5-HT-related drugs for displacing both [125I]iodo-zacopride from its specific binding sites, and [3H]zacopride from 5-HT3 receptors. Finally, [125I]iodo-zacopride was successfully used for the autoradiographic mapping of 5-HT3 receptors in the rat central nervous system.