Influence de la température sur la réponse de communautés microbiennes périphytiques à une exposition métallique : cas du cuivre

Many streams are impacted by metallic pollution. In such ecosystems, microbial communities, which grow preferentially as biofilms, can be affected by these pollutants. However, there is a need to better assess the impact of toxic substances under multi-stress interactions. In this context, the main aim of this work was to evaluate the effect of temperature on biofilm response to copper (Cu) exposure. Accordingly, we addressed the influence of temperature on microbial community sensitivity to Cu on the one hand, and its influence on biofilm exposure to this metal on the other hand. Microcosm experiments were performed under laboratory conditions using biofilms sampled in winter or summer. This work allowed us to set up new methodological developments, which were applied to improve the protocols used to measure (i) Cu tolerance levels of biofilm microbial communities and (ii) Cu bioaccumulation in biofilms. Results showed that temperature could modulate structural and functional effects of Cu on biofilms, notably due to a decrease in Cu bioaccumulation at higher temperatures. In addition, our findings indicate that temperature increase could influence the sensitivity of microbial communities to Cu, whether they have been previously chronically exposed (PICT) or not to this metal. Nonetheless, temperature effects on biofilms varied among experiments, revealing that the influence of temperature on the effects of Cu on microbial biofilms depends on many parameters, such as the initial composition of communities, the level of the applied stresses (temperature and Cu), the microbial compartment studied (i.e. phototrophic or heterotrophic), or the measured functional parametersDe nombreux cours d’eau sont exposés aux polluants métalliques. Dans ces milieux, les communautés microbiennes structurées sous forme de biofilms peuvent être affectées par ces polluants. Or, une des questions prégnantes en écotoxicologie concerne l’évaluation des impacts toxiques dans le cas de combinaisons multi-stress. Dans ce contexte, l’objectif principal de ce travail était d’évaluer l’influence de la température sur la réponse du biofilm à une exposition au cuivre (Cu). Cet objectif a été abordé en considérant l’influence de la température, d’une part, sur la sensibilité des communautés au Cu, et d’autre part, sur l’exposition des communautés de biofilm à ce métal. Ces travaux ont été réalisés en microcosmes de laboratoires et menés sur des biofilms prélevés à différentes saisons. Nous avons tout d’abord optimisé les protocoles utilisés pour mesurer i) les niveaux de tolérance des communautés au Cu et ii) la bioaccumulation du Cu dans les biofilms. Les résultats des expérimentations ont révélé que la température pouvait moduler l’impact structural et fonctionnel du Cu sur les biofilms, du fait notamment d’une diminution de la bioaccumulation aux plus fortes températures. En complément, les résultats ont mis en évidence l’influence d’une hausse de la température sur la sensibilité des communautés au Cu, qu’elles aient été préalablement exposées (PICT) ou non à ce métal. Cependant, nous avons observé que les effets de la température sur la réponse du biofilm étaient variables d’une étude à l’autre, suggérant une influence de nombreux paramètres, tels que la composition initiale de la communauté, les niveaux de stress appliqués (température et Cu), le compartiment microbien étudié (phototrophe ou hétérotrophe), ou les fonctions considérée

Cuisine et bibliothèque

Mémoire de fin d\u27étude du diplôme de conservateur, promotion 25 portant sur l\u27engouement actuel pour la cuisine en France, engouement qui peut se révéler une véritable opportunité pour les bibliothèques de conquérir de nouveaux publics

Subcutaneous emphysema: a rare manifestation of a perforated diverticulitis in a patent inguinal canal

Patients with complicated diverticulitis rarely present with extraperitoneal manifestations but the manifestation of subcutaneous emphysema appears even more seldom. We present the case of a patient with a history of diabetes and immunosuppression, who was admitted with sepsis in association with cellulitis and subcutaneous emphysema of the left groin. The absence of peritonism due to corticosteroid treatment, a history of a recent fall with an ilio- and ischio-pubic fracture and subcutaneous emphysema led to a delay in the diagnosis. The final diagnosis was a perforated diverticulitis in a patent inguinal canal, which was only revealed after surgery. The various complications of diverticulitis, including extraperitoneal manifestations, and associated microorganisms implicated in cellulitis and subcutaneous emphysema are briefly reviewe

Enhancing loco-regional adaptive governance for integrated chronic care through agent based modelling (ABM)

Introduction: Moving from existing segmented care to integrated care is complex and disruptive. It is complex in the sense that the type of changes and the timeframe of these changes are not completely predictable. It is disruptive in the sense that the process of change modifies but also is influenced by the nature of interactions at the individual and organisational level. As a consequence, building competences to govern the necessary changes towards integrated care should include capacity to adapt to unexpected situations. Therefore, the tacit knowledge of the stakeholders (“knowledge-in-practice developed from direct experience; subconsciously understood and applied”1) should be at the centre. However, the usual research and training practices using such a knowledge (i.e. action research or case studies), are highly time-consuming. New approaches are therefore needed to elicit tacit knowledge. One of them is agent based modelling (ABM)2 through computer simulation. The aim of this paper is to make a “showcase” of an agent-based model that uses the emergence of tacit knowledge and enhances loco-regional adaptive governance for improving integrated chronic care. Theory/Methods: We used a complex adaptive system’s lens to study the health systems integration process. We applied key components of ABM to assess how health systems adapts through the dynamics of heterogeneous and interconnected agents (agents are characterised by their level of autonomy, heterogeneity, and interactions with other agents). The agent-based model was developed through a process where concept maps, causal loop diagrams, object-oriented unified modelling language diagrams and computer simulation (using Netlogo©) were iteratively used. Results: The agent-based model was presented to health professionals with variable experience in healthcare to elicit their perceptions and tacit knowledge. It consisted of agents with certain characteristics and transition rules. Agents included providers, patients, networks’ or health systems’ managers. Agents can adopt or influence the adoption of integrated care through learning and because of being aware, motivated and capable of decision making. The environment includes institutional arrangements (e.g., financing, training, information systems and legislation) and leadership. Different scenarios were created and discussed. Key rules to strengthen adaptive governance were reflected on. Discussion and conclusion: This study is an initial step of an exercise to use ABM as a means to elicit of and enhance tacit knowledge to strengthen governance for integrated care. It is expected that the study will foster dialogue between actors of loco-regional projects to integrate health and social care for chronic diseases in Belgium (a new program initiated by federal authorities). Suggestions for future research: Future research is expected to continue developing methods that combine ABM with participative exploration approaches to make better use of tacit knowledge in strengthening loco-regional governance for the development of integrated care

Smoking, genetic polymorphisms of glutathione S-transferases and biological indices of inflammation and cellular adhesion in the STANISLAS study

A recent clinical study has focused on: 1- the interaction between genetic variants of glutathione S-transferases M1 and T1 (GSTM1 and GSTT1) and smoking on the risk of cardiovascular diseases, 2- the potential capacity of GSTM1 and T1 genotypes in modifying the effect of smoking on inflammation and endothelial function. In this study, we investigated whether carriage of these 2 polymorphisms altered the smoking impact on biological indices of inflammation and cellular adhesion. White blood cell count (WBC), albumin, C-reactive protein (CRP), interleukine-6 (IL-6), tumor necrosis factor-alpha (TNF-a), L-selectin, E-selectin, P-selectin and intracellular adhesion molecule-1 (ICAM-1) were measured in 189 non-smokers and 76 smokers (aged 20-55 years) genotyped for the GSTM1 and T1 polymorphisms. Accounting for age and sex, smokers lacking GSTM1 had a higher WBC count, CRP and ICAM-1 levels as compared to the other groups; interaction term between smoking and genotype being significant (p=0.05). Conversely, non-smokers lacking GSTM1 had a higher levels of TNF-a; the test for interaction being significant (p=0.05). No significant interaction was found between smoking and GSTT1 genotypes, considering the 9 biological indices. However, significantly lower levels of IL-6 were noticed for non-smokers with GSTT1-0 null allele (p=0.05). Our study confirms previous results showing that GSTM1 polymorphism could modulate the interrelationships between smoking and biological markers of inflammation and endothelial function

Why Is Case Management Effective? A Realist Evaluation of Case Management for Frail, Community-Dwelling Older People: Lessons Learned from Belgium

Despite many attempts to evaluate the effectiveness of case management for frail older people, systematic reviews including experimental designs show inconsistent results. Starting from the view that case management is a complex intervention occurring in multilayered realities, we conducted a realist evaluation of case management in Belgium, where this type of intervention is new. Realist approaches are particularly well suited to evaluate complex interventions as they seek to investigate iteratively the literature and empirical data to uncover mid-range theories underpinning the intervention under study. As such, realist evaluations are works in progress which provide tools to describe how, why and for whom an intervention is supposed to work. In this paper, we describe two mid-range theories that can explain why case management can help frail older people to remain at home, through the lens of capacity and social support

Gonadotropin administration to mimic mini-puberty in hypogonadotropic males: pump or injections?

Objective: Newborns with congenital hypogonadotropic hypogonadism (CHH) have an impaired postnatal activation of the gonadotropic axis. Substitutive therapy with recombinant gonadotropins can be proposed to mimic physiological male mini-puberty during the first months of life. The aim of this study was to co mpare the clinical and biological efficacy of two treatment modalities of gonadotropins administration during mini-puberty in CHH neonates. Design: Multicenter retrospective analytical epidemiological study comparing two treatments, pump vs injection, between 2004 and 2019. Methods: Clinical (penile size, testis size, testicular descent) and biological parameters (serum concentrations of testosterone, anti-Müllerian hormone (AMH) and Inhibin B) were compared between the two groups by multivariate analyses. Results: Thirty-five patients were included. A significantly higher incre ase in penile length and testosterone level was observed in the injection group compared to the pump group (+0.16 ± 0.02 mm vs +0.10 ± 0.02 mm per day, P = 0.002; and +0.04 ± 0.007 ng/mL vs +0.01 ± 0.008 ng/mL per day, P = 0.001). In both groups, significant increases in penile length and width, testosterone, AMH, and Inhibin B levels were observed, as well as improved testicular descent (odds ratio of not being in a scrotal position at the end of treatment = 0.97 (0.96; 0.99)). Conclusions: Early postnatal administration of recombinant gonadotropins in CHH boys is effective in stimulating penile growth, Sertoli cell proliferati on, and testicular descent, with both treatment modalities

Influence of pressing temperature on dynamics of strength of adhesive bond

Proučevali smo vpliv temperature stiskanja na utrjevanje urea-formaldehidnih (UF) lepil. Uporabili smo dve vrsti UF lepil proizvajalca Basf: Kaurit 345 z nižjo vsebnostjo prostega formaldehida in Kaurit 350 z višjo vsebnostjo. Preizkušanci so bili standardni in sicer iz javorjevega furnirja, debeline 0,6 mm. Preizkušanci so se po razrezu klimatizirali pri sobnih pogojih: 23 °C in 55 % vlažnostjo. Kinetiko utrjevanja UF lepil smo izvedli z ABES (Automated Bonding Evaluation System) instrumentom. Lepilna mešanica je bila skozi vse poizkuse konstantna, sestavljena iz 100 utežnih deležev vodne raztopine lepila in 1,5 % katalizatorja - amonijevega sulfata (glede na suho snov lepila). Testiranje je potekalo pri različnih temperaturah stiskanja: 80, 100, 120, 150, 170 °C. Trajanje stiskanja smo prilagajali glede na razvoj strižne trdnosti. Ko je ABES izmeril strižno trdnost večjo od 0, smo meritev pri enakem času stiskanja ponovili vsaj trikrat. Testirali smo tudi vpliv pH vrednosti različnih furnirjev na utrjevanje UF lepil. Ker katalizator zniža pH vrednost mešanice ter pospeši utrjevanje UF lepil, smo enak princip znižanja pH vrednosti ugotavljali s pomočjo različnih lesnih vrst. Vsaka lesna vrsta ima različno pH vrednost, ki tako dodatno pripomore k spremembi kislosti oz. bazičnosti lepilne mešanice med stiskanjem. Testirali smo preizkušance šestih različnih drevesnih vrst (javor, bukev, hrast, oreh, smreka, brest). S pomočjo termočlena smo raziskali spreminjanje temperature v lepilnem spoju med vročim lepljenjem. Ugotovili smo, da je imela temperatura stiskanja bistveni vpliv na hitrost utrjevanja lepila in da hlajenje preizkušanca po stiskanju ni vplivalo na trdnost spoja. Lepilo z višjim deležem formaldehida je utrjevalo hitreje.We studied the effect of pressing temperature on hardening of urea-formaldehyde (UF) adhesives. We used two types of UF adhesives pre-prepared by manufacturer Basf: Kaurit 345 with a lower content of free formaldehyde and Kaurit 350 with a higher content. For testing of kinetics, we used ABES (Automated Bonding Evaluation System) instrument. To preform standard tests, we used maple veneers, with thickness of 0,6 mm. All veneer was prepared and then left for two day at room conditions of 23 °C and 55 % air humidity, to acclimate. Every test has constant adhesive mixture, consisted of 100 weight units of aqueous adhesive solution and 1,5 % catalyst (ammonium sulphate) (according to dry quantity of glue). Bonding strength was investigated at different pressing temperatures: 80, 100, 120, 150 and 170 °C. Times of gluing were adjusted according to feedback of shear strength. If ABES measured sear strength higher than 0 N/mm2, we carried out at least two more tests of strength. pH value of wood was measured. With usage of different veneers, we tested its influence on bond development. For this test, we used six different species (maple, beech, oak, walnut, spruce, elm). With use of thermocouple we investigated temperature changes in bond during gluing process. We found out that the pressing temperature had a significant influence on hardening time. Cooling specimens after gluing process did not have big effect on joint strength. Adhesive with more formaldehyde was curing faster

Prevalence of HIV-1 drug resistance in treated patients with viral load >50 copies/mL in 2009: a French nationwide study

Background Surveillance of HIV-1 drug resistance in treated patients with plasma viral load (VL) >50 copies/mL. Methods The protease and reverse transcriptase (RT) genes were systematically sequenced in samples from 756 patients with VL >50 copies/mL in 2009. The genotyping results were interpreted for each antiretroviral drug (ARV) by using the ANRS algorithm v21. Weighted analyses were used to derive representative estimates of percentages of patients. Prevalence rates were compared with those obtained in 2004 among patients with VL >1000 copies/mL. Results Sequences were obtained for 506 patients. Sequencing was successful in 45%, 80% and 96% of samples with VL of 51-500, 501-1000 and >1000 copies/mL, respectively. Resistance or possible resistance to at least one ARV was observed in 59% of samples. Overall, 0.9% of samples contained viruses resistant to all drugs belonging to at least three drug classes. All resistance prevalence rates were significantly lower in 2009 than in 2004. Conclusion In France, where 86% of patients were receiving combination antiretroviral therapy in 2009, only 15.0% of patients had a VL >50 copies/mL, suggesting that only 8.9% of treated patients could potentially transmit resistant viruses. Only 0.08% of patients harboured viruses fully resistant to at least three antiretroviral drug classes. Further studies are needed to determine whether resistance continues to decline over tim

Chronic Eczematous Eruptions of the Elderly Are Associated with Chronic Exposure to Calcium Channel Blockers: Results from a Case–Control Study

It has been suggested that chronic eczematous eruptions of the elderly could be associated with chronic drug exposure. To determine the drugs associated with these eruptions, we conducted a case–control study on 102 cases and 204 controls. Cases were consecutive patients older than 60 years presenting with an eczematous eruption that had evolved continuously or recurrently for more than 3 months without a reliable cause. Two controls were matched to each case on age, sex, in/outpatient origin, and center. Information about drug exposure was obtained from patients and their pharmacists. Drug use for more than 3 months within the year preceding the eruption was compared between cases and controls. An association was found between calcium channel blockers (CCB) and eczema, with a matched OR (odds ratio) of 2.5 (95% CI (confidence interval): 1.3–4.6). To ascertain the course of patients after CCB withdrawal, two ancillary studies were performed on 74 patients with eczematous eruptions from our department before the case–control study period, and on 101 patients registered in the French “Pharmacovigilance” database. Healing of these eruptions after CCB withdrawal occurred in 83 and 68% of these cases, respectively. The long-term use of CCB is a risk factor for chronic eczematous eruptions of the elderly