[Quality guidelines for radiopharmacy: Development of a risk-assessment tool]. / Référentiel qualité en radiopharmacie : création d'un outil d'analyse des risques.

OBJECTIVES: The medical management of patients, which involves securing the drug circuit, is a major public health objective. As part of quality management, a number of risk assessment and risk management tools in care units are validated and available. However, medication management in radiopharmacy departments represents a complex and specific process. The aim of the "Quality guidelines for radiopharmacy" working group of the French society of radiopharmacy (SoFRa) was to develop a risk-assessment tool that is a priori adapted to radiopharmacy activity. METHODS: A qualitative risk matrix was developed, based on available analysis tools and current regulations concerning radiopharmacy practice. The tool was then programmed to obtain a summary and scoring for each risk category, as well as a quantitative analysis of the risks identified in radiopharmacy. RESULTS: Our tool contains 262 issues. The qualitative study integrates the risks related to the circuit of radiopharmaceuticals, but also risks related to personnel. The quantitative study makes it possible to carry out an automated analysis of the actions to carry out in priority to improve the practices. CONCLUSIONS: This work led to the development of a self-assessment tool for the a priori analysis of risks that are adapted to the practice of radiopharmacy. It allows easy analysis of the entire circuit of radiopharmaceuticals from a single tool and meet the expectations of health authorities. This common and validated tool is available to the pharmaceutical community.

Ecological speciation in sympatric palms: 2. Pre- and post-zygotic isolation.

We evaluated reproductive isolation in two species of palms (Howea) that have evolved sympatrically on Lord Howe Island (LHI, Australia). We estimated the strength of some pre- and post-zygotic mechanisms in maintaining current species boundaries. We found that flowering time displacement between species is consistent across in and ex situ common gardens and is thus partly genetically determined. On LHI, pre-zygotic isolation due solely to flowering displacement was 97% for Howea belmoreana and 80% for H. forsteriana; this asymmetry results from H. forsteriana flowering earlier than H. belmoreana and being protandrous. As expected, only a few hybrids (here confirmed by genotyping) at both juvenile and adult stages could be detected in two sites on LHI, in which the two species grow intermingled (the Far Flats) or adjacently (Transit Hill). Yet, the distribution of hybrids was different between sites. At Transit Hill, we found no hybrid adult trees, but 13.5% of younger palms examined there were of late hybrid classes. In contrast, we found four hybrid adult trees, mostly of late hybrid classes, and only one juvenile F1 hybrid in the Far Flats. This pattern indicates that selection acts against hybrids between the juvenile and adult stages. An in situ reciprocal seed transplant between volcanic and calcareous soils also shows that early fitness components (up to 36 months) were affected by species and soil. These results are indicative of divergent selection in reproductive isolation, although it does not solely explain the current distribution of the two species on LHI.

Ecological speciation in sympatric palms: 1. Gene expression, selection and pleiotropy.

Ecological speciation requires divergent selection, reproductive isolation and a genetic mechanism to link the two. We examined the role of gene expression and coding sequence evolution in this process using two species of Howea palms that have diverged sympatrically on Lord Howe Island, Australia. These palms are associated with distinct soil types and have displaced flowering times, representing an ideal candidate for ecological speciation. We generated large amounts of RNA-Seq data from multiple individuals and tissue types collected on the island from each of the two species. We found that differentially expressed loci as well as those with divergent coding sequences between Howea species were associated with known ecological and phenotypic differences, including response to salinity, drought, pH and flowering time. From these loci, we identified potential 'ecological speciation genes' and further validate their effect on flowering time by knocking out orthologous loci in a model plant species. Finally, we put forward six plausible ecological speciation loci, providing support for the hypothesis that pleiotropy could help to overcome the antagonism between selection and recombination during speciation with gene flow.

Genital divergence in sympatric sister snails.

A pattern of greater divergence in mating traits between sister-species pairs with overlapping ranges than between allopatric species pairs is expected if reinforcement commonly contributes to speciation. Few large-scale comparative analyses have addressed this prediction, especially for genital form. Here, we show that penial morphology follows the predicted pattern in 40 robustly identified sister-species pairs in the marine gastropod subfamily Littorininae. Further work is needed to exclude other processes that may contribute to genital divergence between sympatric species, but the clear pattern we observe strongly suggests a role for genital form in reproductive isolation in this large clade.

A comparative analysis of the mechanisms underlying speciation on Lord Howe Island.

On Lord Howe Island, speciation is thought to have taken place in situ in a diverse array of distantly related plant taxa (Metrosideros, Howea and Coprosma; Proc. Natl Acad. Sci. USA 108, 2011, 13188). We now investigate whether the speciation processes were driven by divergent natural selection in each genus by examining the extent of ecological and genetic divergence. We present new and extensive, ecological and genetic data for all three genera. Consistent with ecologically driven speciation, outlier loci were detected using genome scan methods. This mechanism is supported by individual-based analyses of genotype-environment correlations within species, demonstrating that local adaptation is currently widespread on the island. Genetic analyses show that prezygotic isolating barriers within species are currently insufficiently strong to allow further population differentiation. Interspecific hybridization was found in both Howea and Coprosma, and species distribution modelling indicates that competitive exclusion may result in selection against admixed individuals. Colonization of new niches, partly fuelled by the rapid generation of new adaptive genotypes via hybridization, appears to have resulted in the adaptive radiation in Coprosma - supporting the 'Syngameon hypothesis'.

Hybridization and speciation.

Hybridization has many and varied impacts on the process of speciation. Hybridization may slow or reverse differentiation by allowing gene flow and recombination. It may accelerate speciation via adaptive introgression or cause near-instantaneous speciation by allopolyploidization. It may have multiple effects at different stages and in different spatial contexts within a single speciation event. We offer a perspective on the context and evolutionary significance of hybridization during speciation, highlighting issues of current interest and debate. In secondary contact zones, it is uncertain if barriers to gene flow will be strengthened or broken down due to recombination and gene flow. Theory and empirical evidence suggest the latter is more likely, except within and around strongly selected genomic regions. Hybridization may contribute to speciation through the formation of new hybrid taxa, whereas introgression of a few loci may promote adaptive divergence and so facilitate speciation. Gene regulatory networks, epigenetic effects and the evolution of selfish genetic material in the genome suggest that the Dobzhansky-Muller model of hybrid incompatibilities requires a broader interpretation. Finally, although the incidence of reinforcement remains uncertain, this and other interactions in areas of sympatry may have knock-on effects on speciation both within and outside regions of hybridization.

Genome annotation and comparative analyses of the odorant-binding proteins and chemosensory proteins in the pea aphid Acyrthosiphon pisum.

Odorant-binding proteins (OBPs) and chemosensory proteins (CSPs) are two families of small water-soluble proteins, abundant in the aqueous fluid surrounding olfactory receptor neurons in insect antennae. OBPs are involved in the first step of olfactory signal transduction, carrying airborne semiochemicals to the odorant receptors and can be classified into three groups: Classic OBPs, Plus-C OBPs and Atypical OBPs. Here, we identified and annotated genes encoding putative OBPs and CSPs in the pea aphid Acyrthosiphon pisum using bioinformatics. This identified genes encoding 13 Classic and two Plus-C OBPs and 13 CSPs. Homologous OBP sequences were also identified in nine other aphid species, allowing us to compare OBPs across several aphid and non-aphid species. We show that, although OBP sequences are divergent within a species and between different orders, there is a high similarity between orthologs within a range of aphid species. Furthermore, the phylogenetic relationships between OBP orthologs reflect the divergence of aphid evolution lineages. Our results support the 'birth-and-death' model as the major mechanism explaining aphid OBP sequence evolution, with the main force acting on the evolution being purifying selection.

Right colonic diverticulitis: an uncommon disease in western countries.

BACKGROUND AND AIMS: Right colonic diverticulitis is not a frequent disease and its management is still controversial. In this study we describe our experience. MATERIAL AND METHODS: We retrospectively reviewed all patients operated on because of a right colonic diverticulitis in our surgical unit. All patients were treated laparoscopically. Demographics, diagnostic and surgical results were recorded. RESULTS: Between January 1994 and January 2007, 11 patients (7 males and 4 females) mean age 53 +/- 9 years (range 39-68), ASA 1: 6 patients, ASA 2: 4 patients, ASA 3: one patient, and BMI 27.8 (range 25-31), had right colonic diverticulitis. Four patients underwent emergency operations: one for peritonitis and three with an erroneous diagnosis of acute appendicitis; seven were operated on electively. There were no deaths or complications. The mean postoperative hospital stay was 5.6 days (range, 3-9). After a mean follow-up of 6.3 years (range 1-13) all patients of this series are symptom-free. INTERPRETATION AND CONCLUSION: Right colon diverticulitis diagnosis remains difficult. A pre-operative imaging screening is necessary to successfully face this challenging disease. Laparoscopy is a safe and effective method to treat these patients. Colectomy should be considered a good therapeutic option for right colonic diverticulitis, although a conservative approach could be proposed in selected cases.

Hybrid sterility and inviability in the parasitic fungal species complex Microbotryum.

Microbotryum violaceum, the anther-smut fungus, forms a complex of sibling species which specialize on different plants. Previous studies have shown the presence of partial ecological isolation and F1 inviability, but did not detect assortative mating apart from a high selfing rate. We investigated other post-mating barriers and show that F1 hybrid sterility, the inability of gametes to mate, increased gradually with the increasing genetic distance between the parents. F2 hybrids showed a reduced ability to infect the plants that was also correlated with the genetic distance. The host on which the F2 hybrids were passaged caused a selection for alleles derived from the pathogen species originally isolated from that host, but this effect was not detectable for the most closely related species. The post-mating barriers thus remain weak among the closest species pairs, suggesting that premating barriers are sufficient to initiate divergence in this system.

On the scent of speciation: the chemosensory system and its role in premating isolation.

Chemosensory speciation is characterized by the evolution of barriers to genetic exchange that involve chemosensory systems and chemical signals. Here, we review some representative studies documenting chemosensory speciation in an attempt to evaluate the importance and the different aspects of the process in nature and to gain insights into the genetic basis and the evolutionary mechanisms of chemosensory trait divergence. Although most studies of chemosensory speciation concern sexual isolation mediated by pheromone divergence, especially in Drosophila and moth species, other chemically based behaviours (habitat choice, pollinator attraction) can also play an important role in speciation and are likely to do so in a wide range of invertebrate and vertebrate species. Adaptive divergence of chemosensory traits in response to factors such as pollinators, hosts and conspecifics commonly drives the evolution of chemical prezygotic barriers. Although the genetic basis of chemosensory speciation remains largely unknown, genomic approaches to chemosensory gene families and to enzymes involved in biosynthetic pathways of signal compounds now provide new opportunities to dissect the genetic basis of these complex traits and of their divergence among taxa.

Elective versus urgent laparoscopic appendectomy for complicated appendicitis.

AIM: Urgent appendectomy in patients with acute appendicitis (AA) complicated by abscess or phlegmon is associated with a high rate of complications. Recent developments in CT scanning have allowed patients with complicated appendicitis to be better identified. We choose to treat these patients with initial antibiotic therapy followed by elective appendectomy. We reported the results of this strategy and compared it with urgent appendectomy. METHODS: A retrospective analysis of patients diagnosed with complicated acute appendicitis (CAA) between 1998 and 2007 treated either by urgent appendectomy or with antibiotic therapy and elective appendectomy was performed. We assessed the efficacy of antibiotic therapy for CAA. We compared the postoperative course between urgent and elective appendectomy. RESULTS: We treated 56 patients with CAA: 40 by urgent appendectomy and 16 by antibiotics. All 16 patients improved with no need for urgent surgery, with 15 undergoing elective appendectomy. Postoperative complications were significantly lower in the elective group. Conversion rate and mean operative time were also lower but not significantly different. However, the duration of total hospital stay, antibiotic therapy and sick leave were higher. CONCLUSIONS: Initial antibiotic therapy followed by elective appendectomy may be proposed in patients diagnosed with CAA.

Characterization of nanomedicines' surface coverage using molecular probes and capillary electrophoresis.

A faithful characterization of nanomedicine (NM) is needed for a better understanding of their in vivo outcomes. Size and surface charge are studied with well-established methods. However, other relevant parameters for the understanding of NM behavior in vivo remain largely inaccessible. For instance, the reactive surface of nanomedicines, which are often grafted with macromolecules to decrease their recognition by the immune system, is excluded from a systematic characterization. Yet, it is known that a subtle modification of NMs' surface characteristics (grafting density, molecular architecture and conformation of macromolecules) is at the root of major changes in the presence of biological components. In this work, a method that investigates the steric hindrance properties of the NMs' surface coverage based on its capacity to exclude or allow adsorption of well-defined proteins was developed based on capillary electrophoresis. A series of proteins with different molecular weights (MW) were used as molecular probes to screen their adsorption behavior on nanoparticles bearing different molecular architectures at their surface. This novel strategy evaluating to some degree a functionality of NMs can bring additional information about their shell property and might allow for a better perception of their behavior in the presence of biological components. The developed method could discriminate nanoparticles with a high surface coverage excluding high MW proteins from nanoparticles with a low surface coverage that allowed high MW proteins to adsorb on their surface. The method has the potential for further standardization and automation for a routine use. It can be applied in quality control of NMs and to investigate interactions between proteins and NM in different situations.

Mice with very low expression of the vesicular monoamine transporter 2 gene survive into adulthood: potential mouse model for parkinsonism.

We have created a transgenic mouse with a hypomorphic allele of the vesicular monoamine transporter 2 (Vmat2) gene by gene targeting. These mice (KA1) have profound changes in monoamine metabolism and function and survive into adulthood. Specifically, these animals express very low levels of VMAT2, an endogenous protein which sequesters monoamines intracellularly into vesicles, a process that, in addition to being important in normal transmission, may also act to keep intracellular levels of the monoamine neurotransmitters below potentially toxic thresholds. Homozygous mice show large reductions in brain tissue monoamines, motor impairments, enhanced sensitivity to dopamine agonism, and changes in the chemical neuroanatomy of the striatum that are consistent with alterations in the balance of the striatonigral (direct) and striatopallidal (indirect) pathways. The VMAT2-deficient KA1 mice are also more vulnerable to the neurotoxic effects of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine in terms of nigral dopamine cell death. We suggest that the mice may be of value in examining, long term, the insidious damaging consequences of abnormal intracellular handling of monoamines. On the basis of our current findings, the mice are likely to prove of immediate interest to aspects of the symptomatology of parkinsonism. They may also, however, be of use in probing other aspects of monoaminergic function and dysfunction in the brain, the latter making important contributions to the pathogenesis of schizophrenia and addiction.

Optimisation of reconstruction, volumetry and dosimetry for 99mTc-SPECT and 90Y-PET images: Towards reliable dose-volume histograms for selective internal radiation therapy with 90Y-microspheres.

PURPOSE: In Selective Internal Radiation Therapy (SIRT), 99mTc-MAA SPECT images are commonly used to predict microspheres distribution but recent works used 90Y-microspheres PET images. Nevertheless, evaluation of the predictive power of 99mTc-MAA has been hampered by the lack of reliable comparisons between 99mTc-SPECT and 90Y-PET images. Our aim was to determine the "in situ" optimisation procedure in order to reliably compare 99mTc-SPECT and 90Y-PET images and achieve optimal personal dosimetry. METHODS: We acquired 99mTc-SPECT/CT and 90Y-PET/CT images of NEMA and Jaszczak phantoms. We found the best reconstruction parameters for quantification and for volume estimations. We determined adaptive threshold curves on the volumetric reconstruction. We copied the optimised volumes on the quantitative reconstruction, named here the "cross volumes" technique. Finally, we compared 99mTc-SPECT and 90Y-PET Dose Volume Histograms. RESULTS: Our "in situ" optimisation procedure decreased errors on volumes and quantification (from -44.2% and -15.8% to -3.4% and -3.28%, respectively, for the 26.5mL PET phantom sphere). Moreover, 99mTc-SPECT and 90Y-PET DVHs were equivalent only after the optimisation procedure (difference in mean dose <5% for the three biggest spheres). CONCLUSIONS: This work showed that a preliminary "in situ" phantom study was necessary to optimise volumes and quantification of 99mTc-SPECT and 90Y-PET images and allowed to achieve a reliable comparison between patient treatment planning and post implant dosimetry, notably by the use of the "cross volumes" technique. Methodology developed in this work will enable robust evaluations of the predictive power of 99mTc-SPECT, as well as dose-response relationship and side effects in SIRT treatments.

Chromatographic behaviour of peptides on a mixed-mode stationary phase with an embedded charged group by capillary electrochromatography and high-performance liquid chromatography.

Retention behaviour of biological peptides was investigated on a stationary phase bearing an embedded quaternary ammonium group in a C21 alkyl chain by both high-performance liquid chromatography (HPLC) and capillary electrochromatography (CEC). In HPLC experiments, variation of acetonitrile (ACN) content in the mobile phase showed that peptides are mainly separated by RP mechanism. The weak or negative retention factors observed as compared to C18 silica stationary phase suggested the involvement of an electrostatic repulsion phenomenon in acidic conditions. Comparison of HPLC and CEC studies indicated that (i) ion-exclusion phenomenon is more pronounced in HPLC and (ii) higher ACN percentage in mobile phase induce for some peptides an increase of retention in CEC, pointing out the existence of mechanisms of retention other than partitioning mainly involved in chromatographic process. This comparative study demonstrated the critical role of electric field on peptide retention in CEC and supports the solvatation model of hydrolytic pillow proposed by Szumski and Buszewski for CEC using mixed mode stationary phase in CEC.

Social interaction increases the extracellular levels of [Met]enkephalin in the nucleus accumbens of control but not of chronic mild stressed rats.

Chronic application of various mild stress has been shown to decrease the responsiveness to reward in rats. This effect, which was suggested to mimic anhedonia, one of the main symptoms observed in depressive patients, can be measured by various tests. Thus chronic mild stress was shown to reduce the consumption of a palatable sucrose solution, and to decrease the acquisition of preferences for a distinct environment paired with a variety of reinforcing substances. These negative responses could be prevented by chronic treatment with tricyclic or atypical antidepressants. The behavioural changes, induced by exposure to chronic mild stress, were shown to be associated with a number of changes in dopaminergic neurotransmission in the mesolimbic system, especially in the nucleus accumbens. The nucleus accumbens contains a large number of enkephalinergic cell bodies giving rise to local collaterals and axons projecting to the globus pallidus-ventral pallidum region (for review see Ref. 9). Furthermore, there is evidence that this structure is instrumental in mediating the reward effects of exogenous and endogenous opioids (for reviews see Refs 5,7,17). This study was carried out to analyse the possible contribution of the enkephalinergic system in the anhedonic-like state induced by chronic mild stress. Microdialysis was used to study the extracellular levels of [Met]enkephalin-like material in the rostral part of the nucleus accumbens of freely moving rats exposed or not to chronically mild stress. In both groups, the basal levels of [Met]enkephalin-like material were found to be similar. Exposure of the two groups to a congener, increased the extracellular levels of [Met]enkephalin in the controls but not in chronic mild stressed rats. This suggests that the reactivity of the endogenous opioid system could be reduced in stress induced model of anhedonia.

Phosphorus-containing peptides as mixed inhibitors of endopeptidase 3.4.24.15 and 3.4.24.16: effect on neurotensin degradation in vitro and in vivo.

1. We have examined several phosphorus-containing peptides as potential mixed inhibitors of two neurotensin-degrading zinc metallopeptidases, endopeptidase 3.4.24.15 and endopeptidase 3.4.24.16. 2. Among a series of 13 phosphonamide peptides, N-(2-(2-naphtyl)ethylphosphonyl-glycyl-prolyl-norleucine (phosphodiepryl 08) was found to inhibit potently the hydrolysis of neurotensin by purified endopeptidase 3.4.24.15 and 3.4.24.16 with an identical Ki value of 0.4 nM. 3. Phosphodiepryl 08 displayed a strong selectivity towards the two peptidases since it failed to inhibit several other zinc-containing peptidases such as endopeptidase 3.4.24.11, angiotensin-converting enzyme, aminopeptidase M, leucine aminopeptidase and carboxypeptidases A and B. 4. The protective effect of phosphodiepryl 08 on neurotensin degradation was examined in vitro and in vivo in central and peripheral bioassays. 5. Phosphodiepryl 08 virtually abolished neurotensin degradation by 4-day-old plated pure cultured neurones from mouse embryos and greatly potentiated neurotensin-induced antinociception in the mouse hot plate test. 6. In the periphery, phosphodiepryl 08 inhibited neurotensin degradation by membranes prepared from isolated longitudinal smooth muscle of guinea-pig ileum and greatly potentiated the neurotensin-induced contraction of the same longitudinal smooth muscle preparation. 7. Our study indicates that phosphodiepryl 08 behaves as a potent and selective mixed inhibitor of endopeptidase 3.4.24.15 and 3.4.24.16 and can be used as a powerful agent to prevent neurotensin degradation, in vitro and in vivo, in central and peripheral assays.

Behavioural and biochemical evidence for signs of abstinence in mice chronically treated with delta-9-tetrahydrocannabinol.

Tolerance and dependence induced by chronic delta-9-tetrahydrocannabinol (THC) administration were investigated in mice. The effects on body weight, analgesia and hypothermia were measured during 6 days of treatment (10 or 20 mg kg(-1) THC twice daily). A rapid tolerance to the acute effects was observed from the second THC administration. The selective CB-1 receptor antagonist SR 141716A (10 mg kg(-1)) was administered at the end of the treatment, and somatic and vegetative manifestations of abstinence were evaluated. SR 141716A administration precipitated several somatic signs that included wet dog shakes, frontpaw tremor, ataxia, hunched posture, tremor, ptosis, piloerection, decreased locomotor activity and mastication, which can be interpreted as being part of a withdrawal syndrome. Brains were removed immediately after the behavioural measures and assayed for adenylyl cyclase activity. An increase in basal, forskolin and calcium/calmodulin stimulated adenylyl cyclase activities was specifically observed in the cerebellum of these mice. The motivational effects of THC administration and withdrawal were evaluated by using the place conditioning paradigm. No conditioned change in preference to withdrawal associated environment was observed. In contrast, a conditioned place aversion was produced by the repeated pairing of THC (20 mg kg(-1)), without observing place preference at any of the doses used. This study constitutes a clear behavioural and biochemical model of physical THC withdrawal with no motivational aversive consequences. This model permits an easy quantification of THC abstinence in mice and can be useful for the elucidation of the molecular mechanisms involved in cannabinoid dependence.

The attenuation of morphine-conditioned place preference following chronic mild stress is reversed by a CCKB receptor antagonist.

Chronic exposure to mild unpredictable stress has been found to abolish the acquisition of preference for a distinctive environment paired with morphine, whereas morphine induced conditioning place preference in non-stressed rats. Chronic treatment for 21 days with the tricyclic antidepressant imipramine reversed the motivational effects produced by chronic mild stress, and animals showed a place preference for the morphine-paired compartment. When the CCKB receptor antagonist PD-134,308 was co-administered with morphine in stressed animals during the conditioning period, the preference for the morphine-paired compartment was also re-established. The CCKB receptor antagonist given alone did not induce rewarding effects in this paradigm. These findings indicate that the administration of a CCKB receptor antagonist reversed the effects of chronic mild stress on opiate rewarding properties.

Opposite role of CCKA and CCKB receptors in the modulation of endogenous enkephalin antidepressant-like effects.

Systemic administration of RB 101, a complete inhibitor of the enkephalin degrading enzymes, has been reported to induce naltrindole-reversed antidepressant-like effects in the conditioned suppression of motility (CSM) test in mice. The selective CCKB antagonist L-365,260 also elicits the same naltrindole-blocked responses on CSM. The aim of this study was therefore to investigate the possible modulation of RB 101 induced behavioral responses by activation or blockade of CCK receptors. Thus, the effects induced by RB 101 administered alone or associated with an ineffective dose of a selective CCKB agonist (BC 264), a CCKB antagonist (L-365,260) or a CCKA antagonist (L-364,718), were evaluated on the CSM in mice. RB 101 alone decreased the stress-induced loss of motility, as previously reported. The antidepressant-like effect of RB 101 was potentiated by L-365,260, and suppressed by BC 264 and to a lesser extent by L-364,718. The facilitatory effect induced by L-365,260 on RB 101 responses was blocked by the delta selective antagonist naltrindole. All these effects occurred only in shocked animals. The present results suggest that the activation of CCKA and CCKB receptors by endogenous CCK, could play an opposite role in the control of behavioral responses induced by endogenous enkephalins. Delta opioid receptors seem to be selectively involved in this interaction.