Nocardia Astéroïdes

Les auteurs décrivent la présence de l'infection à Nocardia astéroïdes en France, chez la vache laitière, à localisation mammaire, plus particu lièrement. Mais d’autres espèces peuvent être touchées. Les mammites sont rebelles à tous traitements et le pronostic économique de l'animal est sombre. L’affection touche les animaux plus particulièrement en pic de lactation. 31 foyers ont été dénombrés du printemps 1982 à l'automne 1983 dans plusieurs départements de France. 55 souches ont été étudiées. Ils soulignent les possibilités de transmission à l'homme et souhaitent une recherche systématique de ce germe dans les laboratoires.The authors described the infection for Nocardia asteroides particulary in the mastitis of cows in French, but other species may be ill. 55 strains of Nocardia asteroides are isolated from 31 outbreaks of infections, during the years 1982-1983. This germ is very antibiotic resistant. They emphasize the possibility of transmission to man and wish systematical research of this germ in the laboratories

Biofilm formation at the solid-liquid and air-liquid interfaces by Acinetobacter species

Abstract Background: The members of the genus Acinetobacter are Gram-negative cocobacilli that are frequently found in the environment but also in the hospital setting where they have been associated with outbreaks of nosocomial infections. Among them, Acinetobacter baumannii has emerged as the most common pathogenic species involved in hospital-acquired infections. One reason for this emergence may be its persistence in the hospital wards, in particular in the intensive care unit; this persistence could be partially explained by the capacity of these microorganisms to form biofilm. Therefore, our main objective was to study the prevalence of the two main types of biofilm formed by the most relevant Acinetobacter species, comparing biofilm formation between the different species. Findings: Biofilm formation at the air-liquid and solid-liquid interfaces was investigated in different Acinetobacter spp. and it appeared to be generally more important at 25°C than at 37°C. The biofilm formation at the solid-liquid interface by the members of the ACB-complex was at least 3 times higher than the other species (80-91% versus 5-24%). In addition, only the isolates belonging to this complex were able to form biofilm at the air-liquid interface; between 9% and 36% of the tested isolates formed this type of pellicle. Finally, within the ACB-complex, the biofilm formed at the air-liquid interface was almost 4 times higher for A. baumannii and Acinetobacter G13TU than for Acinetobacter G3 (36%, 27% & 9% respectively). Conclusions: Overall, this study has shown the capacity of the Acinetobacter spp to form two different types of biofilm: solid-liquid and air-liquid interfaces. This ability was generally higher at 25°C which might contribute to their persistence in the inanimate hospital environment. Our work has also demonstrated for the first time the ability of the members of the ACB-complex to form biofilm at the air-liquid interface, a feature that was not observed in other Acinetobacter species

Hypoxanthine-guanine phosophoribosyltransferase (HPRT) deficiency: Lesch-Nyhan syndrome

Deficiency of hypoxanthine-guanine phosphoribosyltransferase (HPRT) activity is an inborn error of purine metabolism associated with uric acid overproduction and a continuum spectrum of neurological manifestations depending on the degree of the enzymatic deficiency. The prevalence is estimated at 1/380,000 live births in Canada, and 1/235,000 live births in Spain. Uric acid overproduction is present inall HPRT-deficient patients and is associated with lithiasis and gout. Neurological manifestations include severe action dystonia, choreoathetosis, ballismus, cognitive and attention deficit, and self-injurious behaviour. The most severe forms are known as Lesch-Nyhan syndrome (patients are normal at birth and diagnosis can be accomplished when psychomotor delay becomes apparent). Partial HPRT-deficient patients present these symptoms with a different intensity, and in the least severe forms symptoms may be unapparent. Megaloblastic anaemia is also associated with the disease. Inheritance of HPRT deficiency is X-linked recessive, thus males are generally affected and heterozygous female are carriers (usually asymptomatic). Human HPRT is encoded by a single structural gene on the long arm of the X chromosome at Xq26. To date, more than 300 disease-associated mutations in the HPRT1 gene have been identified. The diagnosis is based on clinical and biochemical findings (hyperuricemia and hyperuricosuria associated with psychomotor delay), and enzymatic (HPRT activity determination in haemolysate, intact erythrocytes or fibroblasts) and molecular tests. Molecular diagnosis allows faster and more accurate carrier and prenatal diagnosis. Prenatal diagnosis can be performed with amniotic cells obtained by amniocentesis at about 15–18 weeks' gestation, or chorionic villus cells obtained at about 10–12 weeks' gestation. Uric acid overproduction can be managed by allopurinol treatment. Doses must be carefully adjusted to avoid xanthine lithiasis. The lack of precise understanding of the neurological dysfunction has precluded development of useful therapies. Spasticity, when present, and dystonia can be managed with benzodiazepines and gamma-aminobutyric acid inhibitors such as baclofen. Physical rehabilitation, including management of dysarthria and dysphagia, special devices to enable hand control, appropriate walking aids, and a programme of posture management to prevent deformities are recommended. Self-injurious behaviour must be managed by a combination of physical restraints, behavioural and pharmaceutical treatments

Analyse, limites et perspectives de la prise en compte des micropolluants dans l'ACV du traitement des eaux usées

L'efficacité d'une station de traitement des eaux usées se mesure classiquement par la qualité de ses rejets dans les milieux aquatiques. Mais ce traitement est obtenu avec pour conséquences d'autres impacts environnementaux qui se produisent lors de la construction, de l'exploitation, du fonctionnement et du démantèlement du système d'assainissement dans sa globalité. L'Analyse du Cycle de Vie (ACV) environnementale est la seule méthode d'évaluation, capable de quantifier ces impacts sur l'ensemble du cycle de vie du système. Associée à des approches plus locales telles que les études d'impacts qui prennent mieux en compte les spécificités du site, l'ACV permet d'éviter les transferts de pollution. Afin que l'ACV puise devenir progressivement un indicateur supplémentaire décisionnel d'un choix objectif, il convient de l'appliquer progressivement aux différents systèmes d'assainissement tout en améliorant la méthodologie. C'est dans ce contexte que l'ONEMA a confié à l'Irstea cette action visant à développer les connaissances et à proposer des outils et des méthodes autour de l'approche ACV des systèmes d'assainissement

Jusqu'à quel point la réduction des pertes en eau est-elle écologique ? : ACV des scénarios de réduction de perte en eaux dans les réseaux d'eau potable

International audienceIn a context of increasing water shortage all over the world, water utilities must minimise losses in their distribution networks and draw up water loss reduction action plans. While leak reduction is clearly an important part of sustainable water management, its impacts have to be reconsidered in a broader objective of environmental protection than strictly the avoided losses in cubic metres of water. Reducing the volume of water abstracted reduces also environmental impacts associated to water production (the operation and infrastructure needed for abstraction, treatment, supply). In the mean time, activities for reducing water losses generate their own environmental impacts, notably as a result of the work, equipment, and infrastructures used for this purpose. In this study, Life Cycle Assessment (LCA) was used to assess and compare two sets of environmental impacts: those resulting from the production and supply of water which will never reach subscribers, and those caused by water loss reduction activities. This information can then be used to establish whether or not there is a point beyond which loss reduction is no longer effective in reducing the environmental impacts of drinking water supply. Results show that the improvement actions that start from a low water supply efficiency are clearly beneficial for ecosystems, human health and preservation of resources. When seeking to improve the efficiency beyond certain values (about 65%), the uncertainty makes it impossible to conclude for an environmental benefit on all impact categories.Dans un contexte de pénurie croissante de l'eau partout dans le monde, les services publics d'eau doivent minimiser les pertes dans leurs réseaux de distribution et d'élaborer des plans d'action de réduction des pertes d'eau. Alors que la réduction de la fuite est clairement un élément important de la gestion durable de l'eau, ses impacts doivent être réexaminées dans un objectif plus large de protection de l'environnement que strictement les pertes évitées en mètres cubes d'eau. La réduction du volume d'eau prélevée réduit également les impacts environnementaux associés à la production de l'eau (le fonctionnement et l'infrastructure nécessaires pour le captage, le traitement, l'approvisionnement). Dans le même temps, les activités visant à réduire les pertes d'eau génèrent leurs propres impacts environnementaux, notamment à la suite des travaux, l'équipement et les infrastructures utilisées à cette fin. Dans cette étude, l'évaluation du cycle de vie (ACV) a été utilisé pour évaluer et comparer les deux séries d'impacts environnementaux: ceux qui résultent de la production et la fourniture de l'eau qui ne sera jamais atteindre les abonnés, et ceux causés par les activités de réduction des pertes d'eau. Cette information peut ensuite être utilisée pour établir si oui ou non il y a un point au-delà duquel la réduction des pertes est plus efficace pour réduire les impacts environnementaux de l'approvisionnement en eau potable. Les résultats montrent que les actions d'amélioration qui commencent à partir d'une faible efficacité de l'approvisionnement en eau sont clairement bénéfique pour les écosystèmes, la santé humaine et la préservation des ressources. Lorsque l'on cherche à améliorer l'efficacité au-delà de certaines valeurs (environ 65%), l'incertitude, il est impossible de conclure un avantage environnemental sur toutes les catégories d'impact

Comment introduire l'ACV dans la décision publique : leçons tirées d'un calculateur simplifié pour les systèmes d'assainissement

International audienceLife Cycle Assessment (LCA), although widely disseminated in the industrial sector, remains underutilized in the public sector. The literature has addressed the relationship between scientific knowledge and decision-making from positivist and relativist epistemological perspectives. Both provide explanations for this weak dissemination and suggest solutions. Several of these solutions were explored through the implementation of a simplified LCA calculator in the public wastewater sector in France. This experiment highlighted the importance of two simplification principles: the first is to provide a calculator that already includes a catalogue of LCA ready-for use; the second is to guide the interpretation of LCA results by reducing, step by step, the number of impacts considered. A special effort has been made on the graphic format used to presents results. These principles can be generalized to other contexts. This work calls for the involvement of management sciences in LCA research and for co-building solutions with potential users

An innovative implementation of LCA within the EIA procedure: lessons learned from two wastewater treatment plant case studies

International audienceLife Cycle Assessment (LCA) has been identified in the literature as a promising tool to increase the performance of environmental assessments at different steps in the Environmental Impact Assessment (EIA) procedure. However, few publications have proposed a methodology for an extensive integration, and none have compared the results with existing EIA conclusions without LCA. This paper proposes a comprehensive operational methodology for implementing an LCA within an EIA. Based on a literature review, we identified four EIA steps that could theoretically benefit from LCA implementation, i.e., (a) the environmental comparison of alternatives, (b) the identification of key impacts, (c) the impact assessment, and (d) the impact of mitigation measures. For each of these steps, an LCA was implemented with specific goal and scope definitions that resulted in a specific set of indicators. This approach has been implemented in two contrasting Wastewater Treatment Plant (WWTP) projects and compared to existing EIA studies. The results showed that the two procedures, i.e., EIAs with or without inputs from LCA, led to different conclusions. The environmental assessments of alternatives and mitigation measures were not carried out in the original studies and showed that other less polluting technologies could have been chosen. Regarding the scoping step, the selected environmental concerns were essentially different. Global impacts such as climate change or natural resource depletion were not taken into account in the original EIA studies. Impacts other than those occurring on the project site (off-site impacts) were not assessed, either. All these impacts can be significant compared to those initially considered. On the other hand, unlike current LCA applications, EIAs usually address natural and technological risks and neighbourhood disturbances such as noises or odours, which are very important for the public acceptability of projects. Regarding the impact assessment, even if the conclusions of the EIAs with or without LCA were partially common for local on-site impacts, LCA gives crucial additional information on global and off-site impacts and highlights the processes responsible for them. Finally, for all EIA steps investigated, interest in LCA was demonstrated for both WWTP case studies. The feasibility in terms of skills, time and cost of such implementation has also been assessed