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The myxospermous species Arabidopsis thaliana extrudes a polysaccharidic mucilage from the seed coat epidermis during imbibition. The whole seed mucilage can be divided into a seed-adherent layer and a fully soluble layer, both layers presenting natural genetic variations. The adherent mucilage is variable in size and composition, while the soluble mucilage is variable in composition and physical properties. Studies reporting both the genetic architecture and the putative selective agents acting on this natural genetic variation are scarce. In this study, we set up a Genome Wide Association study (GWAS) based on 424 natural accessions collected from 166 natural populations of A. thaliana located south-west of France and previously characterized for a very important number of abiotic and biotic factors. We identified an extensive genetic variation for both mucilage layers. The adherent mucilage was mainly related to precipitation and temperature whereas the non-adherent mucilage was unrelated to any environmental factors. By combining a hierarchical Bayesian model with a local score approach, we identified 55 and 28 candidate genes, corresponding to 26 and 10 QTLs for the adherent and non-adherent mucilages, respectively. Putative or characterized function and expression data available in the literature were used to filter the candidate genes. Only one gene among our set of candidate genes was already described as a seed mucilage actor, leaving a large set of new candidates putatively implicated inseed mucilage synthesis or release. The present study lay out foundation to understand the influence of regional ecological factors acting on seed mucilage in A. thaliana. • Arabidopsis seed adherent mucilage is mainly related to precipitation and temperature. • Genome Wide Association study (GWAS) based on 424 regional Arabidopsis accessions. • Extensive genetic variation exists for both seed mucilage layers. • 83 new candidates genes have been identified. [ABSTRACT FROM AUTHOR]

Few studies have highlighted the impact of urbanization and meteorological events on the quantity of microplastics (MPs) discharged into the sea through rivers. To evaluate this issue in the Mediterranean Basin, surface water samples were collected from two more or less urbanized Lebanese Rivers: the Nahr Ibrahim (S1) and the Nahr Antelias (S2), during dry and wet periods. A significant higher abundance of 14.02 ± 9.8 particles/L was reported in the most industrialized river S2 compared to 1.73 ± 1.38 particles/L at S1. A correlation was found between particle contamination and the season at each site. Our results indicate that the MP concentrations were highest on the first sampling day of the wet season and tended to decrease progressively with increasing cumulative precipitation. Some polymers were identified only during one season. Meteorological events should be taken more specifically into account in order to define the influx of plastic pollution into coastal waters more accurately. • Urbanization is a key factor in increasing particle abundance at river outlets. • Correlations between seasons and particle abundances were observed at each site. • Some polymers were only identified during one season. • Decrease of particle abundance with increase cumulative precipitations highlighted. [ABSTRACT FROM AUTHOR]

There is increasing interest in using rabbits for research as a laboratory model as well as for industrial production of meat, wool and fur. Superovulation in animals is used to produce a maximum number of transferable embryos per donor, in order to either support genetic improvement programs, ex situ conservation or to optimize other biotechnologies. Over time, the use of this biotechnology has shown variable outcomes as a consequence of several factors, such as the origin of exogenous hormone, posology and the effect of gonadotropins used simultaneously, the donor and the environment. The aim of this study was to compare the efficacy of a single injection of corifollitropin alfa (CTP), alone or supplemented with LH, versus a FSH standard protocol of five equal doses administered twice daily to superovulate rabbit does (20 per group and 29 control females). We determined: 1) the impact of this stimulation on in vitro development and mRNA expression at blastocyst stage and 2) in vivo embryo development and viability rate at birth of transferred embryos. Our outcomes showed that the ovulation rate was similar among the different ovarian stimulation groups, reaching more than fourfold the ovulation rate of a control doe. While rates of embryos developing to the blastocyst stage after 48 h of in vitro culture were similar between groups, the hatched blastocyst rate was higher for superovulated embryos from CTP group. Moreover, no significant differences among mRNA expression of OCT4 , SOX2 and NANOG genes were detected. Nevertheless, embryos from ovarian stimulated does with CTP + LH showed significantly higher implantation rates and survival at birth among the different ovarian stimulation groups and similar to those in the control group. In conclusion, the results of this study suggest that a single injection of long acting corifollitropin alfa can be effectively used in rabbits to elicit a more than fourfold increase in ovulation rate compared to control animals. In addition, the LH supplementation allows us to obtain similar in vivo embryo development results as in the control group. [ABSTRACT FROM AUTHOR]

Assisted reproduction technologies require ovarian stimulation to increase the number of oocytes and embryos. Currently, superstimulation is achieved by gonadotropin treatment, but the embryo yield and quality are highly variable. Commonly, commercial preparations derived from pituitary and urinary origin are used to superovulate. Hence, ovarian superstimulation protocols have usually included both FSH and LH. The appearance of recombinant gonadotropins manufactured by genetic engineering techniques has ensured high quality and batch-to-batch consistency. Moreover, this enables us to assess the importance of LH in the ovarian stimulation. The main aim of this study was to evaluate the effect of recombinant human LH supplementation (10%) on embryonic development produced by rabbit does superovulated with low or high concentration (18.75 or 37.50 IU) of recombinant human FSH (rhFSH). Females treated with rhFSH increased the ovulation rate, and it was significantly higher when the high FSH dose was supplemented with LH. The superstimulation treatment used did not significantly affect in vitro development rate until the expanded blastocyst stage. The results of this study seem to suggest that, in terms of superovulatory response, when rabbit does are treated with 37.5-IU rhFSH, the use of LH supplementation allows an increase in the number of follicles recruited and the quality of embryos, in terms of ability to develop in vitro until blastocyst, and the expression profile of OCT4 , NANOG , and SOX2 genes is not affected. [ABSTRACT FROM AUTHOR]

Abstract: Ovulation induction in artificially inseminated rabbits by adding GnRH synthetic analogues in the seminal doses is a welfare-orientated method to induce ovulation in rabbits and could have some advantages in field practice. This study was conducted to determine the effect of male genotype on the aminopeptidase activity in rabbit seminal plasma and the effects of dilution rate of semen on availability and reproductive performance when buserelin acetate is added to the seminal dose. To study the aminopeptidase activity, 12 mature bucks belonging to a paternal line and 12 from a maternal line were used. The bucks from the paternal line were used to study the effect of dilution rate on the availability of buserelin acetate after 2 hours of dilution and on the reproductive performance of the doses after artificial insemination of 389 commercial crossbreed does. Aminopeptidase activity in seminal plasma is dependent on the male genotype. The paternal line resulted 27% more aminopeptidase activity than the maternal line (P < 0.05). On the other hand, semen diluted 1:20 exhibited a marked increase in the availability of buserelin acetate and the fertility in this group was significantly higher than females from dilution rate 1:5 group, which showed similar results to that of the negative control group (does inseminated with semen diluted 1:20 in non–GnRH-supplemented extender). We conclude that the bioavailability of buserelin acetate when added to the seminal dose appears to be determined by the activity of the existing aminopeptidases and is consequently affected by the dilution rate used to prepare the artificial insemination doses. [Copyright &y& Elsevier]

Abstract: Vitrification of embryos is being increasingly important for cryopreservation in mammals. However, damage and toxicity has to be reduced even more. The composition of cryoprotective medium used to immerse the embryos affects viability and developmental potential. The aim of this work was to assess the effect of the Polyvinylalcohol-PVA- and Dextran addition to vitrification media on the in vitro development of rabbit embryos from superovulated and non-superovulated females. Superovulation group were treated intramuscularly with 25 IU rhFSH. The vitrification media contained the same permeable cryoprotectans (Ethylene Glycol-ET- and Dimethyl Sulfoxide-Me2SO-) and different macromolecules (PVA and Dextran) in different combinations. There was a significantly higher proportion of embryos without damages in mucin coat or zona pellucida after warming (undamaged embryos) in the control than in the superovulation group (95.8% vs. 83.2%, respectively). The proportion of undamaged embryos was significantly affected by the vitrification solution composition. The rate of undamaged embryos after warming in media containing 20% Me2SO was significantly lower in media supplemented with PVA than in media with dextran (67.3 vs. 93.8, respectively). However, the proportion of undamaged embryos for the medium supplemented with dextran was similar for media with 15 or 20% Me2SO. In conclusion, the addition of dextran to the vitrification media improve the preservation of rabbit embryos and permits to reduce the amount of Me2SO for vitrification. Additionally, in vitro developmental ability of undamaged embryos were not affected by superovulation treatment nor vitrification media. [ABSTRACT FROM AUTHOR]

Abstract: This study aimed first to evaluate the effect of recombinant human FSH (rhFSH) with and without recombinant human LH (rhLH) on fresh and frozen-thawed embryo development and also to analyze the immune response of rabbit does (Oryctolagus cuniculus) subjected to repeated rhFSH treatments. Nulliparous New Zealand White does were used. In Experiment 1, 120 does were superovulated with 25 IU rhFSH alone or in combination with 5% or 10% rhLH (1.25 IU or 2.50 IU rhLH). A total of 1116 embryos at the compacted morula stage were cultured at 38.5°C, 5% CO2, and saturated humidity for 48h. The embryo development to hatching blastocyst was significantly lower for the group with 10% rhLH versus that of the control group (65.6 vs. 79.5 for rhFSH+10% rhLH vs. control, respectively). However, no significant difference was found in development to hatching blastocyst for the control, rhFSH alone, and rhFSH+5% rhLH groups. The developmental potential of frozen-thawed embryos obtained from all groups was similar, with an 83.5% in vitro development rate until the expanded blastocyst stage. To detect anti-FSH antibodies, in Experiment 2, does were subject to four superovulation treatments. The hormone administration had a significant effect on immune response in the superovulation group after two treatments (0.14±0.074 and 0.15±0.076 vs. 0.46±0.078 and 0.50±0.078 optical density for the first, second, third, and forth cycles, respectively). Nevertheless, none of the treated does had an immune response in both the first and second treatments; on the contrary, a significant increase in the antibody levels was observed in these females at the moment of the third and fourth superovulation treatments. In conclusion, rhFSH superovulation treatments increase the reproductive potential of rabbit does. [Copyright &y& Elsevier]

Abstract: The aim of this study was to evaluate the supplementation of semen extender with two synthetic GnRH analogues (buserelin and triptorelin) to induce ovulation in rabbit does submitted to artificial insemination. In a first experiment, 255 receptive multiparous does were inseminated with 0.5mL of Tris–citrate–glucose extender supplemented or not with two GnRH synthetic analogues. Experimental groups were: NC (not supplemented extender), PC (not supplemented extender and does treated with 1μg of buserelin i.m.), B2 (2μg per female buserelin supplemented extender), B5 (5μg per female buserelin supplemented extender), T2 (2μg per female triptorelin supplemented extender) and T5 (5μg per female triptorelin supplemented extender). Thirteen does of NC females ovulated, reaching an ovulation rate similar to the other groups. Ovulation rate was similar in all groups (11.4–12.5). The efficiency of ovulation induction was very low (32.5%) in NC group and showed the higher results in PC females (97.8%). Only B5 females reached similar ovulation induction response than PC group. In a second experiment, 702 receptive does were inseminated to compare fertility and prolificacy parameters from the conventional insemination technique (control group, females treated with 1μg per female of buserelin intramuscularly) versus a supplementation with buserelin or triptorelin (5μg per female) in semen extender (B5 and T5 groups, respectively). Fertility and prolificacy parameters were similar among the groups (77.8% fertility rate, 73.9% kindling rate, 9.4 live born and 9.9 total born). This study demonstrate the possibility of ovulation induction in rabbits by adding two GnRH synthetic analogues in the seminal doses and open up new prospects for changing rabbit insemination procedures. [Copyright &y& Elsevier]

Abstract: This study aimed to evaluate the in vitro and in vivo viability of vitrified and non-vitrified embryos derived from eCG and FSH treatments in rabbit does. Ninety-six nulliparous does were randomly subjected to consecutive superovulation treatments with eCG (20IU/kg body weight intramuscularly (i.m.), eCG group), FSH (3×0.6mg/doe at 24h intervals i.m., FSH group), or without superovulation treatment (control group). Does were artificially inseminated 3 days later and ovulation was induced immediately by hCG (75IU/doe intravenous). Seven experimental groups were differentiated: first FSH and eCG treatment, second FSH and eCG treatment, eCG-interchanged group (does with previous FSH treatment), FSH-interchanged group (does with previous eCG treatments) and control group. Embryos were collected in vivo by laparoscopy 76–80h post-insemination in the first and second recovery cycles and post mortem in the third recovery cycles. The ovulation rate was significantly higher in does treated with the first-FSH than in those treated with eCG or in control does (25.2±2.0 versus 19.2±1.4 to 11.0±1.5, and 12.2±1.2, first-FSH, first-eCG to second-eCG and control groups, respectively, P <0.05). Significant differences were observed in the total recovery influenced by ovulation rate in each group (20.3±2.2 to 9.4±1.2, first-FSH to control groups). Embryo donor rate (donor with at least one normal embryo) was similar among groups with an overall of 75.1%. The number of normal embryos recovered per doe with at least one normal embryo increased significantly in relation to ovulation rate (17.7±2.2 to 8.41±3, first-FSH and control groups). The vitrification of embryos negatively affected their in vitro development to hatched blastocyst in all groups (88.1% versus 48%, P >0.05). However, after embryo transfer, this negative effect was only observed in superovulated vitrified embryos (16.8 and 12.8% versus 39.4% total born rate from eCG, FSH and control vitrified groups, P <0.05). Results indicated that the primary treatments with eCG or FSH increased the number of normal embryos recovered per donor doe, but these embryos are more sensitive to vitrification protocols. [Copyright &y& Elsevier]

The aim of this study was to evaluate the fertilising capacity of males belonging to a rabbit line selected for growth rate using heterospermic insemination and genetic markers. Semen from five males was used to make pools of three of them, and to perform homospermic insemination. Insemination was carried out in receptive multiparous lactating does with 6 million spermatozoa per insemination dose. DNA from 360 young rabbits born from heterospermic insemination, 5 sires and 42 does were amplified to nine microsatellite loci for determination of the offspring rate per male. Although each female was inseminated with the same number of spermatozoa from each male (2 million from a total dose of 6 million), sperm from one male was always dominant, notable differences being observed in the offspring among the males with similar semen quality (83–68% from dominant male versus 31–0% from non-dominant, P<0.05). [Copyright &y& Elsevier]

• Freezing extender with dextran increase post-thaw acrosome membrane integrity. • Dextran would act as a membrane-stabilizing compound. • 5 % dextran in semen freezing extender favourably affects reproductive performance. Effects were analysed of dextran supplementation to Me 2 SO and acetamide rabbit semen freezing extenders on quality characteristics of rabbit spermatozoa and reproductive performance. The final concentration of cryoprotectants in pooled semen samples was 12.4 % Me 2 SO for the A extenders, 10.7 % Me 2 SO and 2.9 % acetamide for the D extenders and 8.9 % Me 2 SO and 2.9 % acetamide in F extenders, with a supplementation of 1.7 % sucrose in all cases. There was not inclusion of dextran in the A0, D0, F0; while 5 % dextran was included in A5, D5, F5 and 10 % dextran in A10, D10 and F10 extenders. Sperm motility and viability rates were similar with use of the different extenders. Acrosome integrity after the freeze-thawing processes, however, was markedly greater when there was dextran supplementation of D and F extenders. Prolificacy was affected by extender composition. When there was artificial insemination (AI) using semen cryopreserved in the A extenders, number of kits born was similar to when there was AI with fresh semen when there was inclusion of 5% dextran for cryopreservation, while there was no effect on prolificacy when there was cryopreservation of semen using the D and F extenders. In conclusion, dextran supplementation of extenders containing Me 2 SO and acetamide resulted in greater acrosome integrity. Furthermore, when there was AI using sperm preserved in cryo-diluents containing an intermediate concentration of Me 2 SO, combined with inclusion of 5 % dextran, there was a marked beneficial effect on rabbit doe reproductive performance. [ABSTRACT FROM AUTHOR]

Artemisia annua is cultivated mainly for isolation of artemisinin, a potent antimalarial compound. Moderate salt stress has been proved to increase the artemisinin synthesis by the plant. The aim of this study was to evaluate the influence of salt stress on physiological parameters and cell wall polysaccharides of A. annua. Plants subjected to salt stress displayed reduction in the biomass and length and showed high damage of cellular membranes. Cell wall polysaccharides extracted from aerial parts with hot water, EDTA and NaOH also exhibited modifications in the yield and monosaccharide composition. The main changes were found in the pectic polysaccharides: increase of homogalacturonan domain, increase of neutral side chains and increase in the methyl esterification. 1H NMR analyses of pectins indicated that for A. annua , arabinans have an important role in coping with salt stress. Hemicellulose domain was also modified under salt stress, with increased xylose contents. The results indicated adaptations in the cell wall of A. annua under salt stress. Image 1 • Salt stress affects the biomass and length of A. annua plants. • Changes in cell wall polysaccharides were observed under salt stress. • Under salt stress, the main changes were found in the structure of pectins. • Under salt stress, HG domain and neutral side chains of pectins increased. • Hemicellulose domain had increased xylose contents under salt stress. [ABSTRACT FROM AUTHOR]

The present study was conducted to characterise rabbit sperm proteins focusing on the influence of the genetic origin. Six samples were recovered during two months from five males from genotype A (New Zealand White origin) and five from genotype R (California origin). Sperm proteins were extracted and subjected to in-gel digestion nano LC-MS/MS and bioinformatics analysis. The resulting library included 487 identified proteins validated with ≥95% Confidence (unused Score ≥ 1.3). All the identified proteins belonged to Oryctolagus cuniculus taxonomy. These data are available via ProteomeXchange with identifier PXD007989. Only 7 proteins were specifically implicated in reproductive processes according to Gene Ontology annotation. Regarding the comparison of the sperm proteins abundance between genotypes, forty proteins were differentially expressed. Among them, 25 proteins were over-expressed in genotype A, while 15 proteins were over-expressed in genotype R. In conclusion, this study characterizes for the first time rabbit sperm proteins and provides evidence that genotype is related to a specific abundance of spermatozoa proteins. Image 1 • First in-depth characterization of rabbit sperm proteome. • 487 proteins were identified and quantified in rabbit spermatozoa. • Genotype is related to specific proteins abundance in sperm. • A publicly accessible database of the rabbit sperm proteome was created. [ABSTRACT FROM AUTHOR]

La vaccination conjuguée pneumococcique 13-valente (PCV13), recommandée en France depuis 2010, semble réduire l’incidence des pneumonies graves. Méthodes Les passages aux urgences des enfants ayant une pneumonie ont été décrits par les résumés de passage aux urgences (RPU), dans 7 services de la région Paca sur la période 2009–2014. Les proportions de passages pour pneumopathies communautaires (PC), bactériennes (PB), virales (PV) ou non spécifiques (PNSP) ont été analysées selon les périodes (avant PCV13, transitionnelle, après PCV13) par régression logistique. Sur les données agrégées journalières, un modèle linéaire a été constitué avec la proportion de PB comme variable dépendante, la période comme variable fixe et la proportion de grippe et de bronchiolite comme covariable. Résultats Sur 718 758 passages, 7 284 étaient codés PC. La proportion de PB était réduite de 52 % après PCV13 (2,49 vs 5,17/1000 passages), alors que celle des PV était inchangée et celle des PNSP augmentait. Cette baisse des passages pour PB restait significative après ajustement sur les grippes et bronchiolites. Conclusion Les RPU permettent une surveillance en temps réel des passages pour pneumopathie des enfants et leur analyse donne des arguments en faveur d’une efficacité du PCV13. [ABSTRACT FROM AUTHOR]

The present study was designed to prove new rabbit insemination extenders containing aminopeptidase inhibitors (AMIs) with or without chitosan (CS)-dextran sulfate (DS) nanoparticles entrapping the GnRH analogue. In addition, different hormone concentrations were tested in these extenders, evaluating their in vivo effect on rabbit reproductive performance after artificial insemination. A total of 911 females were inseminated with semen diluted with the four experimental extenders (C4 group: 4 μg buserelin/doe in control medium (Tris-citric acid-glucose supplemented with bestatin 10 μM and EDTA 20 mM), C5 group: 5 μg of buserelin/doe in control medium, Q4 group: 4 μg of buserelin/doe into CS-DS nanoparticles in control medium, Q5 group: 5 μg of busereline/doe into CS-DS nanoparticles in control medium). Results showed that fertility was significantly lower in C4 group compared to C5, Q5 and Q4 groups (0.7 versus 0.85, 0.85 and 0.82, respectively). On the contrary, prolificacy was similar in the four experimental groups studied (P > 0.05). We conclude that the CS-DS nanoparticles prepared by a coacervation process as carrier for buserelin acetate allows reducing the concentration of hormone used in extenders supplemented with bestatin and EDTA without affecting the fertility and prolificacy of rabbit females. [ABSTRACT FROM AUTHOR]

Superovulation treatments aim to stimulate multifollicular recruitment, maximizing the number of oocytes or transferable embryos produced. Factors associated with the superovulation protocol, female characteristics and many other factors are determinants in the number and quality of oocytes obtained. An accurate way to assess oocyte quality more precise than morphological appearance is genetic expression. The present study aims to compare the response of nulliparous and multiparous females to superovulatory stimulation, studying its effect on the expression of some genes associated with the activation, growth, development and oocyte-embryo transition of oocytes, as well as its impact on in vivo embryonic development and viability rate at birth. In a first experiment, the effect of stimulation treatment on the ovulation response and the expression of the MSY2, MATER, ITPR1, ITPR2, ITPR3, eIF4E, PAR1, PAPOL-A, PAPOL-G, ZAR1 and YY1 genes in nulliparous and multiparous females were determined. In a second experiment, the implantation and viability at birth of embryos from superovulated nulliparous and multiparous females were analysed. The ovulation rate was significantly higher in the superovulation groups than in the control groups. The ovulation rate was significantly increased in nulliparous females compared with multiparous does. From the eleven genes analysed, only the expression of MATER, PAPOL-A, PAPOL-G and ZAR-1 genes was shown to be different among experimental groups. Finally, in terms of implantation rate and viability at birth, the nulliparous control group showed better results than the rest of the groups. Both hyperstimulation treatment and reproductive female's history seem to alter the transcriptome of important genes related to oocyte maturation and competence acquisition, affecting in vivo embryo viability. • CTP + hCG elicits a greater response in nulliparous than in multiparous rabbit does. • The expression of MATER, PAPOL-A, PAPOL-G and ZAR1 is affected by superovulation. • Reproductive female history affects genes related to oocyte maturation. • Reproductive female history affects genes related to competence acquisition. [ABSTRACT FROM AUTHOR]

Abstract: Maternal undernutrition during gestation can condition offspring adult health, with the periconceptional period pointed out as a key period. The aim of this study was to evaluate the effects of maternal periconceptional undernutrition on pregnancy and offspring growth performance in sheep. 52 Merinos d''Arles ewes were fed to requirements (control group, C), whereas 64 ewes received 50% of their dietary needs from −15 to +30 days post-conception (restricted group, R). Thereafter, both groups were fed according to needs. Maternal body weight (BW), body condition score (BCS) and Non Esterified Fatty Acids (NEFA), progesterone, leptin and cortisol plasma concentrations were monitored weekly during the restriction period and the following month, then monthly until weaning. Lambs were weighed weekly until weaning at 22 kg BW, then monthly. Plasma leptin was monitored monthly in lambs. The BW, BCS, and leptin concentrations were significantly decreased, whereas NEFA and cortisol concentrations were increased in R dams. Maximum progesterone concentration was higher in R ewes that had a high (10–25%) vs. low (0–10%) BW loss during restriction (27.9 ± 2.59 vs. 20.8 ± 2.00 ng/mL, P < 0.05). Overall, gestation was significantly longer in the R group (151.0 ± 0.3 vs. 149.4 ± 0.4 days, P < 0.001). There was no difference between groups for pregnancy rates, prolificacy, birth weight and lamb mortality, but the proportion of male lambs was significantly higher in the R group, only for singletons (16/26 vs. 9/26, P < 0.05). Lamb growth was not significantly modified by treatment. Leptin concentrations at birth were significantly lower in R vs. C males (6.15 ± 0.13 ng/mL vs. 7.42 ± 0.36 ng/mL, P < 0.05), whereas in females, leptin concentrations were significantly higher in R vs. C lambs at 4 mo of age (7.31 ± 0.27 ng/mL vs. 6.41 ± 0.29 ng/mL, P < 0.05). These results indicate that maternal periconceptional undernutrition in a hardy breed does not significantly affect lamb birth weight and growth rates, in contrast to previous reports in other breeds, suggesting that caution must be taken when extrapolating programming data between breeds and breeding conditions. [Copyright &y& Elsevier]

Abstract: Prenatal death can occur due to several genetic and environmental factors which alter normal embryo development, maternal environment to support normal fertilisation, development of embryos, placenta and foetus, or affect the necessary relationship between embryo and endometrium. The aim of this work was to study gestational losses and progesterone, 17 β-estradiol and IGF I serum levels in a rabbit line selected for growth rate (paternal line). In this study, a maternal line well characterised in previous studies was used as a reference line. A total of 211 laparoscopies were carried out, and the number of corpora lutea and implanted embryos at 12th days, total born and live born were recorded per female. To analyse the endocrine levels, blood serum was collected from 54 females with implanted embryos at 12th and 24th day of gestation (27 from each line). The paternal line showed the lowest ovulation frequency, number of implanted embryos, total born and live born (0.70, 11.3, 7.4, and 6.4 vs 0.86, 12.8, 11.1 and 10.6 for maternal line, respectively) and consequently, the highest implantation, gestational, foetal and perinatal losses (0.31, 0.60, 0.40, and 0.15, respectively). Progesterone serum levels at 12th days of gestation were similar between lines; however, progesterone serum level at 24th day of gestation was significantly lower in the paternal line (4.8 vs 8.2 ng/mL). Serum levels of 17β-estradiol and IGF-I at 12th days of gestation were different between lines (14.6 vs 26.5 pg/mL, 237 vs 149 ng/mL for paternal and maternal lines respectively). These higher gestational losses of the paternal line could be explained by differences in 17 β-estradiol level at 12th days of gestation and the possible effect on low progesterone serum levels at 24th days of gestation. Further studies in steroid production and bioavailability have to be done during oestrus and pregnancy related with metabolic activity of this line. [Copyright &y& Elsevier]

Abstract: In this work, we investigated the effect of storage in solid-phase extender on buck semen conserved at 5°C. Furthermore, we studied the effect of addition of cysteine to the extender and the washing of seminal plasma on sperm survival. In Experiment 1, milk-based extender (M) was used as a control to study the effect of solid media storage (G) and cysteine supplementation (C), and the combination of both (GC), on in vitro sperm survival of washed and non-washed semen, conserved up to 72h at 5°C. Motility, acrosome integrity (NAR) and hypo-osmotic swelling tests (HOST) were evaluated to assess in vitro sperm survival. In Experiment 2, an artificial insemination (AI) field trial was performed to compare G versus M. Solid media (G) maintained motility of spermatozoa during storage higher than any other extender (67% G versus 62% GC; 61% M and 59% C; P <0.05), but there was no difference in NAR or HOST between extenders (P >0.05). No improvement in sperm viability was obtained by addition of cysteine to the media. Washing of semen improved motility (65% versus 60%; P <0.05), NAR (70% versus 64%; P <0.05) and HOST (37% versus 28%; P <0.05). No significant differences in fertility were obtained between G and M extenders (47% versus 41%; P >0.05). In conclusion, washing of semen and dilution in gelatin-supplemented milk extender (solid storage) appears to be a successful method for goat semen storage at 5°C. [Copyright &y& Elsevier]

Abstract: The aim of the present study was to characterise European eel spermatozoa morphometrically, as a basis for future studies on the morphological effects of methods for sperm cryopreservation and sperm quality. This characterisation was carried out measuring several spermatozoa morphology parameters (head length, width, area and perimeter) by scanning electron microscopy (SEM), in comparison with measurements developed in European eel spermatozoa with computer-assisted morphology analysis (ASMA). Spermatozoa head morphology showed differences in width (1.15±0.01μm versus 1.12±0.01μm), perimeter (14.68±0.13μm versus 13.72±0.19μm) and area (5.36±0.06μm2 versus 1.12±0.01μm2) for ASMA and SEM, respectively. When head length was evaluated, significant differences were found, being higher for SEM methodology (5.09±0.04μm versus 4.29±0.03μm). The curved and elongated spermatozoa head in eels means a problem for the ASMA system (Sperm Class Analyser®, Morfo Version 1.1, Imagesp, Barcelona, Spain), causing an error in the length measurements. However, similar results were obtained by both techniques when spermatozoa head length was considered as the greater length between two points within the object (4.29±0.03μm versus 4.31±0.04μm for ASMA and SEM, respectively). In conclusion, this is one of the first applications of ASMA in fish and the first in this species, and confirms this system as a useful tool with wide applications in future fish spermatozoa studies. Width, perimeter and area could be used as parameters for the spermatozoa morphology evaluation, whereas the length requires a new programming of the Imagesp software. [Copyright &y& Elsevier]

Minimum fungicidal concentrations (MFCs) of amphotericin B were obtained for 165 bloodstream isolates (104 Candida parapsilosis, 14 C.glabrata, 13 C.tropicalis, 15 C.krusei, and 19 C.albicans) and 36 C.dubliniensis from oropharyngeal infections. Minimum inhibitory concentrations (MICs) were determined by the M27-A microdilution method. MFCs (≥99.9% killing) were obtained following MIC determination (inoculum size, 104 CFU/ml) by seeding the entire volume of all clear wells. The best fungicidal activity was for C. albicans, (MFC90 1 μg/ml) and the lowest for C.parapsilosis, C.tropicalis and C.glabrata (MFC90 16 μg/ml). Although MFCs were ≥16× MIC for some isolates, including C. glabrata, the overall MFCs were ≥2× MICs. However, major differences between MICs and MFCs were observed for C.parapsilosis and C.dubliniensis (3.8% and 8.9%, respectively, were tolerant: MFC ≥32MIC). MFCs for C.tropicalis and C. glabrata were ≥2 μg/ml. By this more stringent method we found substantial differences from those previously reported between amphotericin B MIC and MFCs for Candida spp. [Copyright &y& Elsevier]

The present study was conducted to characterise rabbit seminal plasma proteins (SP proteins) focusing on the influence of the genetic origin and seasonality. In addition, β-NGF protein quantity in SP was determined. Semen samples were recovered from January to December 2014 using 6 males belonging to genotype A and six from genotype R. For each genotype, one pooled sample at the beginning, middle and end of each season was selected to develop the experiment. A total of 24 pools (3 for each season and genetic line) were analysed. SP proteins of the two experimental groups were recovered and subjected to in-solution digestion nano LC–MS/MS and bioinformatics analysis. The resulting library included 402 identified proteins validated with ≥95% Confidence (unused Score ≥ 1.3). These data are available via ProteomeXchange with identifier PXD006308. Only 6 proteins were specifically implicated in reproductive processes according to Gene Ontology annotation. Twenty-three proteins were differentially expressed between genotypes, 11 over-expressed in genotype A and 12 in genotype R. Regarding the effect of season on rabbit SP proteome, results showed that there is no clear pattern of protein variation throughout the year. Similar β-NGF relative quantity was observed between seasons and genotypes. In conclusion, this study generates the largest library of SP proteins reported to date in rabbits and provides evidence that genotype is related to a specific abundance of SP proteins. [ABSTRACT FROM AUTHOR]

The addition of aminopeptidase inhibitors (AMIs) to rabbit semen extenders could be a solution to decrease the hormone degradation (GnRH) by the aminopeptidases existing in the seminal plasma. Therefore, the quantity of GnRH needed to induce ovulation in doe would be comparable with the amount administered intramuscularly (i.m.). This study was conducted to evaluate the effects of two AMIs (bestatin and EDTA) on rabbit semen quality parameters, β nerve growth factor (β-NGF) degradation and reproductive performance after artificial insemination. Results showed that seminal quality was not affected by the incubation with AMIs; the values of motility, acrosome integrity and sperm viability were not significantly different between the AMIs and the control groups (positive i.m. and negative intravaginally without AMIs). In addition, the aminopeptidase activity of seminal plasma was inhibited in a 55.5% by the AMIs as well as β-NGF degradation. On the other hand, regarding the effect of AMIs on reproductive performance, our results showed that the presence of bestatin and EDTA did neither affect fertility (85.3 vs. 88.6%), nor the prolificacy rate (10.12 vs. 10.51 kits per delivery), comparing AMIs group to positive control group, respectively. We conclude that the addition of specific AMIs in the rabbit semen extender has no effect on reproductive performance. Therefore, due to the fact that AMIs inhibit part of the aminopeptidase activity that degrades the GnRH analogue and β−NGF, they could be used to develop new extenders with less hormone concentration. [ABSTRACT FROM AUTHOR]

The bioavailability of buserelin acetate when added to the seminal dose appears to be determined by the activity of the existing aminopeptidases. Thus, the addition of aminopeptidase inhibitors to rabbit semen extenders could be a solution to decrease the hormone degradation. This study was conducted to evaluate the effect of the protease activity inhibition on rabbit semen quality parameters and reproductive performance after artificial insemination. Seminal quality was not affected by the incubation with protease inhibitors, being the values of motility, viability, and acrosome integrity not significantly different between the protease inhibitors and the control group. In addition, seminal plasma aminopeptidase activity was inhibited in a 55.1% by the protease inhibitors. On the other hand, regarding the effect of protease inhibitors on reproductive performance, our results showed that the presence of protease inhibitors affected the prolificacy rate (9.2 ± 0.26 and 9.3 ± 0.23 vs. 8.2 ± 0.22 total born per litter for negative control, positive control, and aminopeptidase inhibitors group, respectively; P < 0.05), having this group one kit less per delivery. We conclude that the addition of a wide variety of protease inhibitors in the rabbit semen extender negatively affects prolificacy rate. Therefore, the development of new extenders with specific aminopeptidase inhibitors would be one of the strategies to increase the bioavailability of GnRH analogues without affecting the litter size. [ABSTRACT FROM AUTHOR]

Cooling sperm to and equilibrating the sperm at 5 °C require the most time in any sperm cryopreservation protocol. Reducing the time required for these phases would simplify sperm freezing protocols and allow greater number of ejaculates to be processed and frozen in a given time. This study determined how holding rabbit sperm at 5 °C for different lengths of time (0, 10, 15, 20, 30, or 45 minutes) affected the quality of rabbit sperm, measured by in vitro assays, and if reducing the cooling time to only 10 minutes affected the fertilizing ability of the sperm. Reducing the time sperm were held at 5 °C to 10 minutes did not affect the in vitro quality of the sperm (percent motile and with intact plasma membranes), although eliminating the cooling phase completely (directly freezing the sperm from room temperature) decreased in vitro assessed sperm quality (P < 0.01). However, reducing the time sperm were held at 5 °C, from 45 to 10 minutes, negatively affected the fertilizing ability of sperm in vivo (P < 0.05). In conclusion, completely eliminating cooling rabbit sperm to 5 °C before freezing is detrimental for rabbit sperm cryosurvival, and although shortening the time sperm are held at 5 °C to 10 minutes does not reduce in vitro sperm quality, it does reduce the fertility of rabbit sperm. Therefore, the length of time rabbit sperm equilibrate at 5 °C is crucial to the fertilizing ability of rabbit sperm and must be longer than 10 minutes. Currently, it is not known if holding rabbit sperm at 5 °C for less than 45 minutes will affect sperm fertilizing ability. [ABSTRACT FROM AUTHOR]

Abstract: The study evaluated a seminal effect on the ability to induce ovulation of a synthetic GnRH analogue, buserelin acetate, administered by vaginal mucosa in rabbit does. In a first experiment, 751 receptive nulliparous and multiparous non-lactating does were randomly assigned to groups of different seminal doses (6, 12, 24, 50, and 100 million total sperm in 0.5 mL). All seminal doses contained 5μg of buserelin acetate to induce ovulation by vaginal mucosa absorption. Two hundred and six does from 751 were laparoscopized at 12th days of gestation to evaluate ovulation induction, ovulation rate and implanted embryos, while pregnancy rate and total and live born were noted in all females. Results showed that the pregnancy rate was significantly affected by the seminal dose used (0.82 vs 0.72, 0.50, and 0.45, for 6, 24, 50, and 100 million of spermatozoa, respectively). Data from laparoscopized does showed significant differences between the group of 6 and 50 million sperm dose in the ovulation induction and consequently in the pregnancy rate (0.79 vs 0.52, 0.79 vs 0.48, respectively). Does from all groups had similar implanted embryos and litter sizes irrespective of seminal dose used. In a second experiment, inseminations were done without spermatozoa, 0.5 mL of two dilutions of seminal plasma (1/4 and 1/20) with 5μg of buserelin acetate were introduced into vagina from 71 receptive females and its results were compared to a control group (35 does) induced to ovulate with 1μg of buserelin acetate administered intramuscularly. Only 40% of females from 1/4 plasma dilution group became to ovulate. Consequently, the dilution rate of seminal plasma may reduce the availability rate of the GnRH analogue and the concentration needed to provoke the ovulation induction. [Copyright &y& Elsevier]

Summary: Aim of the study: To evaluate the values of clinical signs and the rapid diagnostic test (RDT) in the diagnosis of influenza H1N1 new variant in the pediatric emergency room. Method: From 18 August to 1st December 2009, children admitted to the pediatric emergency department of CHU Nord (Marseille, France) and suspected of flu according to French guidelines, were tested for influenza using both an influenza RDT and a polymerase chain reaction (PCR) assay specific for H1N1. From 3 November to 3 December, clinical signs were also noted (fever, headaches, myalgia-arthralgia, shivers, diarrhea). Results: A total of 1122 children were tested: 367 children (32.1%) had a positive specific PCR. The RDT value was: sensitivity 65.2% [55.8–73.6], specificity 99.5% [98.1–100], positive predictive value (PPV) 97.5% [91.8–100], negative predictive value (NPV) 91.2% [90.3–91.5], positive likelihood ratio (LRP) 153.7 [53.5–452.9] and negative likelihood ratio (LRN) 0.393 [0.387–0.411]. Clinical data were available for 504 children (328 over 2 years of age). In children more than 2 years of age and in multivariate analysis, headaches were the only sign significantly associated with a positive PCR (aOR=2.53 [1.25–5.12]). Overall, headaches and/or myalgia-arthralgia were valuable indicators for clinical diagnosis of flu, with a 75.8% NPV. Among children with a positive PCR, diarrhea was more frequent in children under 2 years of age (OR=2.76 [1.19–6.40]). The sensitivity of the RDT improved (90.9% [85.2–94.6]) when flu signs were also present. Conclusion: Associating clinical signs and RDT for the diagnosis of influenza A (H1N1) new variant in a pediatric emergency room improves selection of children requiring appropriate antiviral treatment. [ABSTRACT FROM AUTHOR]

The present study, comprising a prospective multicentre study including 53 non-neutropenic patients from intensive care units (ICU) in six Spanish tertiary-care hospitals, was carried out to determine the clinical significance and influence on mortality of Candida albicans germ tube-specific antibodies (CAGTA). There were 22 patients (41.5%) for whom the CAGTA results were positive, although none of had a blood culture positive for Candida. The intra-ICU mortality rate was significantly lower (p = 0.004) in CAGTA-positive patients (61.2% vs. 22.7%). Multivariate analysis confirmed that a positive CAGTA result was the only protective factor to be independently associated with ICU mortality (β coefficient = −0.3856; 95% confidence interval = −0.648 to −0.123). [ABSTRACT FROM AUTHOR]

Abstract: Candida guilliermondii fungemia is usually described in adults with hematologic malignancies, but in children, only 2 episodes have been published. From 1995 to 2006, 7 episodes (5 in children) were detected in our hospital. Molecular typing excluded a common infection source. C. guilliermondii fungemia may occur in children with underlying conditions other than cancer. [Copyright &y& Elsevier]

Abstract: Fish sperm quality has traditionally been estimated by subjective evaluation of motility and sperm concentration. Alternative methods for evaluation of sperm quality have been developed in the last decade and enable estimation of spermatozoa head morphometry, membrane integrity and mitochondrial function. Weekly injections of human chorionic gonadotropin (hCG) induced spermiation in farmed male European eels. The milt volume increased from the 5th to 12th weeks. Sperm concentration significantly increased from the 5th week, reaching the highest values at the 8th week, while best motility results were registered at the 9th week of treatment. Coinciding with these intervals, the percentage of dead spermatozoa determined with Hoechst staining showed a reduction in the 8th to 11th weeks of treatment, while the percentage of mitochondrial functionality determined by JC-1 staining did not show a similar pattern. The automatic sperm morphology analysis (ASMA) of the spermatozoa head length, width, area and perimeter showed a significant growth from the 5th to 8th weeks. However, the analysis of isolated descriptive parameters may be difficult to understand because there is a variability in these parameters for each week, making knowledge of the growth kinetic complex. The global size of the spermatozoa head was calculated by applying principal component analysis (PCA), because this method establishes new components that make the interpretation of results easier, allowing a whole interpretation of the changes in the cell morphology. PC1 defines the global head size and shows a significant increase between the 5th and 8th weeks of treatment, showing shorter changes until 12th week. PC2 shows a significant increase in the spermatozoa width from the 5th to 7th weeks. Considering the results of the variations in the principal components defining European eel spermatozoa morphometry, it may be concluded that hCG maturative treatment produced thick cells during the first weeks of spermiation, and subsequent samplings showed an increase in cell width and length. These changes in sperm morphometry coincide with the highest sperm quality assessed as sperm motility and concentration, as well as with the best results obtained in previous studies reporting the best sperm quality between weeks 8 and 10 of hCG treatment. These results support the use of ASMA and Hoechst staining techniques as alternative methods for the evaluation of fish sperm quality. [Copyright &y& Elsevier]

Abstract: The aim of this work was to evaluate the effect of different doses of eCG administered subcutaneously (0, 50 and 200IU) and the hormonal induction of ovulation (GnRH or hCG) on embryo recovery and in vitro development of embryos post-vitrification in two selected lines of rabbit does. The two selected lines were line V (selected for the litter size at weaning) and line R (selected for growth rate). Administration of 200IU of eCG significantly increased ovulation rate (19.2±1.2 versus 15.5±1.1 and 12.2±1.3, and the number of haemorrhagic follicles (13.8±1.6 versus 3.8±1.4 and 3.8±1.7), but significantly decreased recovery rate (28.8±6.3 versus 47.7±5.7 and 48.7±6.7, 200IU versus 50IU and 0IU eCG, respectively), the number of normal embryos recovered per doe with at least one embryo (5.8±0.9 versus 8.2±0.9, 200IU versus 50 IU eCG doses) and the in vitro development of embryos post-vitrification (51.9% versus 66.1%, 200IU versus 50IU eCG doses, respectively). Inducing ovulation with hCG significantly increased ovulation rate when compared with GnRH (17.3±0.8 versus 13.8±1.4), but no significant differences in embryo recovery and embryo development post-vitrification were observed between the two treatments. No significant differences were observed between the two selected lines in ovulation and recovery rates, the number of haemorrhagic follicles and the number of recovered embryos per doe. However, the post-vitrification in vitro rate of development was 59.7% for line R and 51.9% for line V (p <0.05). It was concluded that the use of 50IU of eCG subcutaneous with hCG or GnRH prior to embryo cryopreservation programmes in rabbits achieves the best results for embryo recovery, with the best development of recovered embryos post-vitrification. [Copyright &y& Elsevier]

Abstract: In this study, we evaluated the potential effect of the method of recovery (artificial vagina or electroejaculation) on the production and quality of Guirra ram spermatozoa cryopreserved for the possible constitution of a sperm bank. In order to address this question, we evaluated the effect of semen collection method on fresh semen quality parameters, including: volume, concentration, production, microscopic analysis (abnormal sperm and intact apical ridge) and sperm motility parameters determined by CASA system. For frozen–thawed semen, we evaluated motility parameters by CASA and intact apical ridge, acrosomal status, assessed by dual staining by IP and FITC-PNA and capacitation status, assessed by M540 and Yo-pro1, using flow cytometry. The main findings from this study were: (i) that electroejaculation resulted in a lower recovery efficiency (80% of the cases), as a consequence of contamination with urine or lack of response to the electrical stimulation; (ii) the fresh seminal quality was not significantly different between recovery methods, except for the concentration of spermatozoa, but total number of spermatozoa and the consequent number of possible seminal doses for artificial insemination were similar; and, (iii) a higher number of stable and functional spermatozoa (higher number of live non-capacitated cells, higher live acrosome intact cells and live acrosome reacted cells) were found for frozen–thawed spermatozoa collected by electro ejaculation than by artificial vagina. According to our results, we are able to develop both methodologies in the creation of the Guirra sperm bank. Assuming the advantages and limitations of both methodologies, in Guirra breed, would enable the rapid constitution of a sperm bank including samples from a large number of non-trained rams in a short period of time, which will increase the genetic variability, and so guarantee the conservation of this breed. [Copyright &y& Elsevier]

Abstract: This study was conducted to determine if different sperm characteristics correlate with the in vivo fertility of rabbit sperm. A total of 2765 heterospermic inseminations were performed in commercial rabbitries using 50-pooled samples of fresh semen. Sperm motility and morphological evaluations were performed on each of the heterospermic pooled samples to asses the seminal quality, and the percentage of kindling rate (76.2%) and number of kits born alive (9.3) were recorded. Sperm motility parameters, assessed using a computer-assisted sperm analysis (CASA) system (Sperm Class Analyzer, Microptic, Barcelona, Spain), were: average path velocity, curvilinear velocity, straight-line velocity, linearity, amplitude of lateral head displacement, beat cross-frequency, wobble and percentage of total motile spermatozoa. Morphological analyses included the percentage of sperm with a normal apical ridge, the percentage of sperm with cytoplasmatic droplets and the percentage of abnormal sperm. Significant correlations were observed between kindling rate and the percentage of total motile cells (r =0.31; P &#60;0.05), linearity index (r =−0.32; P &#60;0.05) and the percentage of abnormal sperm in the sample (r =−0.32; P &#60;0.05). Regression models including motility and the morphological parameters explained 45% of the variation in kindling rate. These results indicate that motility parameters, determined by CASA systems, in combination with sperm morphology analyses can provide some information about the fertilizing potential of rabbit sperm. [Copyright &y& Elsevier]

La cervicalgie est une pathologie fréquente en population générale comme en milieu professionnel pour laquelle le recours à l'imagerie nécessite d'être précisé. La Haute Autorité de santé (HAS) et le Conseil professionnel de la radiologie française (G4) ont piloté la production de fiches de pertinence de l'imagerie cervicale en cas de cervicalgie. Dans ce cadre la Section Rachis reconnue par la Société Française de Rhumatologie a été sollicitée pour participer aux différents groupes de travail. Du fait de l'insuffisance de littérature de fort niveau de preuve, la méthode retenue a été celle de recommandations par consensus formalisé (HAS, 2015). Elle s'est déroulée en quatre phases : rédaction des propositions par un groupe de pilotage ; cotation par un second groupe afin d'identifier les points d'accord et de divergence et de sélectionner les propositions qui font l'objet d'un consensus ; relecture externe de la version initiale des fiches par un troisième groupe d'experts pluriprofessionnel et finalisation : analyse des commentaires des relecteurs, corrections et rédaction de la version finale lors d'une réunion associant groupes de pilotage et de cotation. (1) Cervicalgie non traumatique : L'imagerie cervicale est indiquée d'emblée en cas d'épisode de cervicalgie associée à des drapeaux rouges (atteinte neurologique, signes évocateurs de pathologie néoplasique, infectieuse, inflammatoire ou de dissection artérielle). Elle doit se discuter en cas d'épisode de cervicalgie commune persistant plus de 4 à 6 semaines. Elle n'est pas indiquée en cas d'épisode de cervicalgie commune (avec ou sans radiculalgie) évoluant depuis moins de 4 à 6 semaines. Lorsqu'elle est indiquée, l'imagerie cervicale de 1ère intention est l'IRM en cas de suspicion de maladie inflammatoire rhumatismale, infectieuse ou tumorale, de NCB persistant plus de 4 à 6 semaines et avant un geste invasif. L'angio-IRM est indiquée en présence de signes de dissection artérielle cervicale, les radiographies standard en cas de cervicalgie persistant plus de 4 à 6 semaines sans NCB. (2) Cervicalgie traumatique : Après un traumatisme cervical non pénétrant, l'imagerie cervicale est indiquée chez les patients instables ou présentant des troubles de conscience ou des signes neurologiques ; si elle est préconisée par l'une des deux règles suivantes : National Emergency X-Radiography Utilization Study (NEXUS) [1] ou Canadian C-Spine [2] ; chez les sujets de 65 ans ou plus ; en cas de rachis ankylosé ; si une dissection artérielle cervicale est suspectée. Dans les autres cas, l'imagerie cervicale n'est pas indiquée. L'imagerie cervicale de 1ère intention, lorsqu'elle est indiquée, est le scanner qui pourra être complété en cas de suspicion d'atteinte vasculaire (angioscanner) ou médullaire (IRM). Les présentes préconisations sont une aide à la décision. Fonder le raisonnement sur ces recommandations permettra aux professionnels de santé d'optimiser le recours à l'imagerie cervicale. [ABSTRACT FROM AUTHOR]

Objectifs L’objectif principal est de mesurer l’impact des particules en suspension (PM), estimé à proximité du domicile des enfants, sur les admissions pour exacerbation d’asthme aux urgences dans le département des Bouches-du-Rhône en 2013 chez l’enfant. Matériel et méthodes Un cas témoins emboîté dans une cohorte est réalisé chez les enfants de 3 à 18 ans. L’appariement était aléatoire sur le jour de la consultation aux urgences. L’exposition aux PM 10 et PM 2,5, les données météorologiques, polliniques et virologiques du jour de consultation étaient corrélées au code géographique du domicile du patient et analysées par rapport au motif de consultation. Résultats principaux Notre étude concernait 68 897 consultations, dont 1182 asthmatiques. L’exposition à court terme aux PM 10 était associée à un excès de risque de consultation pour asthme (RR = 1,02, IC 95 % :1,01–1,04 ; p = 0,02). Le sexe masculin, le jeune âge et la température étaient également des facteurs de risque. Par contre, le vent était retrouvé comme facteur protecteur. Conclusion Les PM 10 et certains facteurs météorologiques, estimés au plus proche du domicile des enfants, augmentent le risque de consultation aux urgences pour exacerbation d’asthme chez les enfants de 3 à 18 ans dans les Bouches-du- Rhône. [ABSTRACT FROM AUTHOR]