Comparaison de techniques d’identification des Erwinia et des Pseudomonas responsables de la pourriture molle

Trois méthodes, soit la caractérisation physiologique, l'utilisation de systèmes miniaturisés d'identification (API 20E, API NFT et Biolog) et l'analyse du profil électrophorétique des protéines sécrétées, ont été expérimentées afin de déterminer une technique précise et rapide d'identification des Pseudomonas et des Erwinia responsables de la pourriture molle. L'analyse des patrons électrophorétiques des protéines sécrétées est une méthode très efficace pour identifier les différentes espèces pectinolytiques de Pseudomonas fluorescents. Le système Biolog reconnaît efficacement le P. marginalis et le P. viridiflava. Le système API NFT est efficace pour l'identification du P. marginalis, du P. viridiflava et du P. syringae. C'est le système API 20E qui s'est avéré le plus efficace pour l'identification des Erwinia. L'électrophorèse des protéines sécrétées et le système API NFT permettent une identification rapide et efficace des Pseudomonas, tandis que pour les Erwinia, seul le système API20E est performant.Three methods, namely physiological characterization, the use of miniaturized identification Systems (API 20E, API NFT, and Biolog) and the analysis of the electrophoretic profile of proteins secreted by the bacteria, were used in order to determine a precise and quick identification technique for the Pseudomonas and Erwinia species causing soft rots in several plant species. The analysis of the electrophoretic profile of the proteins secreted is a very efficient method of identification for the various pectinolytic species of fluorescent Pseudomonas. The Biolog System accurately recognizes P. marginalisand P. viridiflava. The API NFT System is efficient for the identification of P. marginalis, P. viridiflava and P. syringae. The API 20E System was found to be the most reliable System for identifying Erwinia species. The electrophoresis of proteins secreted and the API NFT system allow a quick and efficient identification of Pseudomonas species, while for Erwinia species, only the API 20E System is efficient

Comparison of Mean Arterial Blood Pressure and Heart Rate Changes in Response to Three Different Randomized Isotonic Crystalloid Boluses in Hypotensive Anesthetized Dogs.

The aim of this prospective, randomized, nonblinded, controlled clinical trial was to compare mean arterial blood pressure (MAP) and heart rate (HR) during an intravenous bolus of three different balanced isotonic crystalloid solutions in euvolemic, anesthetized dogs with hypotension. Thirty healthy dogs (American Society of Anesthesiologists Physical Status I-II) weighing at least 15 kg that presented for elective orthopedic or dental surgical procedures at the Ryan Veterinary Hospital for Small Animals of the University of Pennsylvania were included in this study. Anesthetized hypotensive patients (defined as a MAP ≤ 65 mmHg), were administered an infusion of Lactated Ringer's solution (LRS), Plasma-Lyte (PLYTE) or Canadian Plasma-Lyte (PLYTECA), selected at random. The infusion was administered over 15 min via a volumetric fluid pump. Differences in oscillometric MAP and HR between time points and across treatments were evaluated by mANOVA. Intravenous isotonic crystalloid infusions over 15 min did not significantly change MAP or HR in hypotensive dogs under general anesthesia. Neither LRS, PLYTE nor PLYTECA exacerbated hypotension or caused tachycardia

Tracking Landscape-Scale Movements of Snow Buntings and Weather-Driven Changes in Flock Composition During the Temperate Winter

Nomadic movements of migratory birds are difficult to study, as the scale is beyond the capabilities of hand-held telemetry (10 s of kms) but too fine-scale for long-range tracking devices like geolocators (50–100 km accuracy). Recent widespread installation of automated telemetry receiving stations allowed us, for the first time, to quantify and test predictions about within-winter movements of a presumed nomadic species, the Snow Bunting (Pletrophenax nivalis). We deployed coded radio-transmitters on 40 individual Snow Buntings during two winters (2015-16 and 2016-17) in southern Ontario, Canada, and tracked movements over a 300 by 300 km area with 69–77 active radio-receiving stations (Motus Wildlife Tracking Network). To complement our tracking data, we also examined the influence of weather on the demographics of winter flocks at a single wintering site over 6 consecutive years (n = 9312 tagged birds). We recorded movements of 25 Snow Buntings from the deployment sites to 1–6 different radio recievers (mean 2.68 locations/bird). Birds traveled a minimum average distance of 49 km between detections (range: 3 to 490 km) in the core wintering period of Dec-Feb, and cumulative total movements ranged from 3 to 740 km (average 121 ± 46 km). In March distances between detections increased to an average of 110 km, suggesting an extended early-migration period. Overall, older birds (after-second year or older) tended to move more (higher cumulative distances traveled) than younger (first winter) birds, even during the Dec-Feb period. The long-term banding data revealed that larger, male birds were more likely to be captured in colder and snowier weather, relative to female and smaller birds, suggesting that they can withstand these conditions more easily owing to their body size. We have provided the first direct-tracking data on nomadic winter movements of Snow Buntings, and tested the hypothesis that winter weather drives flock composition at a single site. Site-specific banding data suggest that weather-related changes in flock composition could explain the nomadic, landscape-scale movements of Snow Buntings we observed by using automated telemetry. Future work should explore the importance of resource availability, competition, and predation risk as drivers of winter movements in Snow Buntings

Orientações para a avaliação das intervenções visando a prevenção dos Problemas Músculo-Esqueléticos ligados ao trabalho

Mejorar las prácticas de intervención constituye hoy en día un desafío en el campo de la prevención de lesiones músculo esqueléticas (LMS) relacionadas con el trabajo. El desarrollo de conocimientos sobre la intervención en las empresas es un desafío para la intervención dirigida a su evaluación. La investigación internacional en el campo de las LMS concentra sus trabajo y recomendaciones sobre la evaluación de los efectos de las intervenciones mediante la evaluación de los síntomas de salud o de las exposiciones. En este texto mostramos en primer lugar, que esta orientación supone que se reúnan un cierto número de condiciones importantes, generalmente subestimadas y a menudo difíciles de reunir. Proponemos que se tomen en cuenta, en tanto criterios complementarios de la evaluación, los indicadores relacionados a la actividad de trabajo y a los márgenes de maniobra, aunque señalamos que estos indicadores necesitan ser trabajados para volverlos operacionales. En segundo lugar, sostenemos que para desarrollar conocimientos sobre la intervención se necesita describir precisamente el proceso de intervención y tomar en cuenta el contexto en el que se desarrolla, por ello, la evaluación de sus efectos es insuficiente para desarrollar conocimientos sobre la intervención. Por último, la discusión señala que, desde nuestra perspectiva, la evaluación de las intervenciones constituye un proyecto en sí y que este contribuye directamente a la transformación del trabajo

Mucolipidosis II : a single causal mutation in the N-acetylglucosamine-1-phosphotransferase gene (GNPTAB) in a French Canadian founder population

Mucolipidosis (ML) II (I-cell disease) is a lysosomal storage disorder caused by a deficiency of UDP-N-acetylglucosamine:lysosomal enzyme N-acetylglucosamine-1-phosphotransferase. MLII is an autosomal recessive disease with a carrier rate estimated at 1/39 in Saguenay-Lac-Saint-Jean (SLSJ) (Quebec, Canada), which is the highest frequency documented worldwide. To identify the causing mutation, we sequenced GNPTAB exons in 27 parents of 16 MLII-deceased children from the SLSJ region as obligatory and potential carriers. We also performed a genealogical reconstruction for each parent to evaluate consanguinity levels and genetic contribution of ancestors. Our goal was to identify which parameters could explain the high MLII frequency observed in the SLSJ population. A single mutation (c.3503_3504delTC) was found in all obligatory carriers. In addition, 11 apparent polymorphisms were identified. The mutation was not detected in genomic DNA of 50 unrelated controls. Genealogical data show six founders (three couples) with a higher probability of having introduced the mutation in the population. The frequency of the mutation was increased as a consequence of this founder effect and of the resulting population structure. We suggest that c.3503_3504delTC is the allele causing MLII in the SLSJ population, and its high carrier rate is most likely explained by a founder effect

Contribution of hierarchical clustering techniques to the modeling of the geographic distribution of genetic polymorphisms associated with chronic inflammatory diseases in the Québec population

Objectives: The purpose of this project was to evaluate the potential of the downward hierarchical clustering analysis (DHCA) for studying genetic heterogeneity, i.e. differences in allele frequency in subpopulations, such as the 15 public health regions of the province of Québec (Canada). Methods: The study relied on an anonymized sample of 1,680 individuals who had participated in the Québec Heart Health Survey in 1990-1991. The genotyping of 11 variants in 8 candidate genes known to be involved in chronic inflammatory diseases, namely asthma and cardiovascular diseases, was performed using the amplification refractory mutation system and restriction fragment length polymorphism techniques. Only variants showing an allelic frequency >2% in the Québec Heart Health Survey (n = 8) were selected. DHCA techniques were then applied to model the geographical distribution of these 8 genetic variants in 15 Québec public health regions and to study genetic heterogeneity. Results: The DHCA allowed to group public health regions and gene variants on the basis of genetic variability. For both asthma and cardiovascular diseases, 3 significant clusters of public health regions and 1 cluster of gene variants were identified. Discussion: This study suggests that DHCA might be useful in studying genetic heterogeneity at the population level and for public health activities

Suspensions cellulaires embryogènes de bananiers et bananiers plantain

This guideline presents two protocols to produce embryogenic cell suspensions by using scalps or immature male flowers. The protocols have been developed by the Laboratory of Tropical Crop Improvement of Katholieke Universiteit Leuven (KULeuven) and the cellular biology laboratory of the Centre de coopération internationale en recherche agronomique pour le développement (Cirad)