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Glucagon-like peptide 1 level and risk of death within 90 days after intensive care unit admission: A substudy of the IVOIRE cohort
No full textInternational audienceBackground Elevated plasma levels of glucagon-like peptide-1 (GLP-1) have been associated with poor clinical outcome in patients with sepsis. This study investigated the association between GLP-1 levels, and survival at 90 days in a large cohort of critically ill patients. Methods All patients aged ≥ 18 years admitted to the intensive care unit (ICU) in a large university hospital, and receiving ≥1 life support therapy for organ failure were eligible for inclusion. Plasma samples were taken within 24h of ICU admission. We measured GLP-1 using a commercial ELISA kit. Cumulative probability of death at 90 days (D90) was plotted using the Kaplan-Meier method by quartiles of GLP-1. The effect of GLP-1 quartile on D90 survival was analyzed using a Cox proportional hazards model. Results A total of 507 patients had GLP-1 dosage; mean age 64.5 ± 14.5 years; 179 (35.3%) women. GLP-1 levels ranged from 0.03 to 129.2 (median 7.3[IQR:3.3;19.1]). Higher mean age, SOFA, SAPS II, and LPS 3HM were found in patients with higher GLP-1 quartile by univariate analysis. Overall, 229 patients (45.2%) died within 90 days. The cumulative probability of death was significantly associated with GLP-1 quartile (p log rank<0.0001). After adjustment for age, SOFA, renal replacement therapy and vasopressor treatment, a significantly increased risk was observed only for patients with the highest quartile of GLP-1 (adjusted hazard ratio 1.65 [1.06; 2.56] for 4 th vs 1 st quartile of GLP-1). Conclusion After adjusting for demographic and clinical characteristics, only the highest quartile of GLP-1 remained independently associated with an increased risk of death at 90 days after admission to ICU
Worldviews and values of key societal actors influencing decision‐making around nature: The case of wild pollinator conservation in Europe
No full textInternational audienceBiodiversity is vital for life on earth but faces many anthropogenic pressures. Mitigating these pressures and improving biodiversity status requires understanding the worldviews and values of actors involved in conservation or responsible for creating pressures on biodiversity. This paper contributes to the theoretical understanding of the interplay between worldviews and values and their potential influence on effective policy or practice actions. We investigated the worldviews and values of key European actors influencing a specific component of biodiversity conservation: wild pollinators and pollination. We collected qualitative and quantitative data through in‐depth interviews with 27 individuals from business, policymaking, NGOs and research. Bio‐ecocentric worldviews prevailed in our sample of interviews, with a consensus over the intrinsic value of all living beings, that human activities are negatively impacting nature, the existence of biophysical limits to economic growth and the need for environmental regulation. Furthermore, anthropocentric and relationship‐centred perspectives emerged on the use of pesticides, modes of economic growth (conventional vs. sustainable), the ability of human ingenuity and technological innovation to solve ecological problems and the fundamental resilience of nature to rapid change. Irrespective of overall worldviews on human–nature relationships, all stakeholder groups in our sample agreed on the irreplaceability of pollinators and their many benefits, their decline and that their conservation is a priority for which all sectors of society are responsible and should contribute. Interviewees agreed that in addition to the widely recognised ecological, nutritional, economic and cultural values that pollinators provide, there also exist relational values and moral responsibility to conserve pollinators. Non‐use values (e.g. ecological role) were highlighted by all stakeholder groups as being at least as important as use values (e.g. supporting human diets). Cultural use values (e.g. aesthetic) of pollinators were typically regarded as being less important relative to their non‐use relationship‐centred and moral values (e.g. responsibility to future generations). Policy implications. The diverse values of biodiversity create a complex conservation challenge amid competing societal priorities. The efficacy of public policy instruments critical to facilitate conservation actions can be improved by further integrating ecological, economic, social and moral‐ethical levers to achieve the long‐term sustainable management of biodiversity. Read the free Plain Language Summary for this article on the Journal blog
CH10 -Advances in the reduction of herbicide use in Conservation Agriculture systems
No full textInternational audienceConservation agriculture (CA) appears as a promising agricultural pathway to achieve multiperformance but is currently questioned due to its reliance on herbicides for weed management, especially glyphosate.One limit in the development of CA-based agroecological cropping system less reliant on herbicide use is the strict definition of CA based on technical means (i.e. the three principles) rather than targeted objectives. In this chapter, we mobilize research carried out on experimental stations (e.g. CA-SYS platform) and farmer networks (e.g. French DEPHY-farm network) to synthesize knowledge on how pesticide-free no-till agriculture could be achieved. We provide insights on the multiperformance of pesticide-free and nature-based CA systems compared to reference CA systems. Designing cover crops to ensure growth in a context of unpredictable weather conditions and facilitate mechanical termination, and ensuring crop establishment in absence of tillage and herbicides represent major research avenues for the development of pesticide-free CA systems.</p
Soil-dependent fate of Klebsiella pneumoniae and Listeria monocytogenes after incorporation of digestates in soil microcosms
No full textInternational audienceDigestates are valuable by-products of anaerobic digestion. They can be used as fertilisers/soil improvers in agriculture. We collected six digestates from anaerobic digestors fed with biomass of diverse origins and analysed the occurrence of the process indicator bacteria E. coli and the three pathogens Salmonella enterica, Klebsiella pneumoniae sensu lato (Klebsiella pneumoniae Species Complex, KpSC) and Listeria monocytogenes (Lm). Salmonella enterica was absent in all digestates. Low copy numbers of KpSC were PCR detected in all digestates. In digestate SMS, E. coli was present at low concentration (50 CFU/g), and K. pneumoniae sensu stricto (Kp) along with Lm were detected and isolated after selective enrichment. We designed microcosm experiments to investigate the fate of these pathogens following the application of the digestates to three soils with contrasting edaphic characteristics. After 42 days incubation, S. enterica was not detected in any microcosms, and E. coli was found only in microcosms with silty clay loam soil supplemented with SMS digestate. The frequency of molecular detection of KpSC varied, while Lm was PCR detected only once in the silty clay loam soil supplemented with SMS digestate. Further experiments with artificially contaminated digestate demonstrated that the fate of Kp and Lm was dependent on soil type and that their detection duration correlated with their initial concentration in the digestate. Additionally, we explored an integrated statistical analysis framework to uncover the relationship between soil microbial diversity and the occurrence of KpSC. This last analysis highlighted both the potential of microbial communities to act as natural barrier against pathogens, and the complexity of microbial community dynamics affecting the pathogen's presence
Sodium Alginate as a promising encapsulating material for extremely-oxygen sensitive probiotics
No full textInternational audienceThe next-generation probiotics (NGPs) exhibit great therapeutic potential. However, some of these are found extremely oxygen-sensitive (EOS), leading to various challenges for their production, processing, storage, and colonic delivery. Sodium alginate (SA) appears as a promising encapsulating material for EOS probiotics thanks to its excellent oxygen barrier properties as well as optimal release behavior in simulated gastrointestinal fluid (SGF). This work comprehensively examines the effects of SA structural characteristics, molecular weight (MW), and Mannuronic/Guluronic (M/G) ratio on its functional properties as an encapsulating material for the protection and controlled release of 3 NGP strains, including Lactiplantibacillus plantarum, Bifidobacterium longum subsp. infantis and Faecalibacterium duncaniae (EOS strain).The results show that the rheological properties of SA are notably influenced by MW but not by the M/G ratio. Autoclaving SA powder significantly reduces the viscosity of SA solution. Although cross-linking with divalent cations slightly increases oxygen permeance, this still provides effective protection against oxygen for encapsulated microorganisms. SA beads with high MW and low M/G ratio form stronger gels due to effective G block crosslinking, while a high M/G ratio promotes bead swelling in SGF. The low MW SA beads dissolve in SGF after 4 h, especially the one with high M/G ratio which appears as ideal for swelling, solubility, and probiotic release. Even though pure SA does not protect enough probiotics in SGF, adding sodium carbonate and L-cysteine to the polymer matrix preserves F. duncaniae viability up to 6 logs CFU∙mL−1 after exposure to SGF
Biochemical composition of feed ingredients influences equine gastric ecosystem activity in vitro
No full textInternational audienceWhen the pH of the gastric environment decreases below 4, acidity and volatile fatty acids (VFAs) can damage the epithelium. Depending on the feed ingredients incorporated in horse feeds, gastric ecosystem can be modified. Dehydrated alfalfa might be of interest because of its biochemical composition, which provides a strong acid buffering capacity. We ran an in vitro trial to assess the impact of three dehydrated alfalfas differing in biochemical composition on the persistence of acid buffering capacity over time in a gastric ecosystem undergoing fermentation. Barley and wheat bran were used for comparison.Five substrates were prepared from 0.5 g dry matter (DM) barley, completed with 0.5 g DM alfalfa, wheat bran, or barley. Substrates were added to a modified Lowe culture medium in bottles under sterile conditions. After inoculation with gastric contents collected from horses, the bottles were incubated anaerobically for 10-hours. Every two hours, the gas produced, the concentration of VFAs and lactate, the pH, and the amount of 0.1 M hydrochloric acid (HCl) required to decrease the pH of the solution down to 4 were measured in triplicate.The pH of the feed ingredients was close (5.81 −6.29), but 7 −12 times more HCl was needed to bring the pH down to 4 with alfalfa compared to barley, and 3 −5 times more compared to wheat bran. This acid buffering capacity was correlated with ash content (r = 0.984; P = 0.002), and particularly calcium content (r = 0.995; P < 0.001). Fermentations started faster in bottles containing alfalfa (P < 0.001 after 2 h), but then gas production was higher with barley and wheat bran (P < 0.001). However, VFA concentrations remained higher with alfalfa than other substrates (P < 0.05), and the higher the content in proteins and simple sugars the more pronounced the differences. While the pH of the solution and the amount of HCl required to decrease to pH4 fell sharply over the 10-hour monitoring period, these variables remained higher with alfalfa compared to barley and wheat bran substrates (P < 0.001 after 6-hours for pH; P < 0.05 after 4-hours for HCl amount). Despite their different biochemical composition, the impact of the three alfalfas in the environment was close. These results suggest that adding alfalfa to feeds could contribute maintaining a higher pH in the horse stomach. This seems to arise from intrinsic high acid buffering capacity of alfalfa, rather than from the reduction in gastric fermentations. Considering the acid buffering capacity of feed ingredients in the formulation of horse feed could help maintain a physiological gastric pH for longer and reduce gastric diseases
Roughness from Alpha Stable Images Applied to Fossil Images
No full textInternational audienceAmong the parameters used to study the texture of an object's surface is the roughness descriptor. The digital image of the object surface is used to provide roughness descriptors mainly when the surface studied is deformable or damaged by a roughness meter. This work proposes a new roughness descriptor from the image. The particularity of this descriptor is that it is adapted to surfaces containing significant fluctuation (enormous variation). This descriptor is constructed from the estimator of the spectral density of alpha stable processes. To compare our method to other methods developed in the literature, we measured the sensitivity of the descriptors to random Gaussian noise added to each image. In this work, some images of fossils representing significant variation are the subject of the images studied. This study shows that our descriptor is more sensitive than other descriptors for this kind of image (the sensitivity value is higher). Thus, the originality of this work lies in proposing a descriptor adapted to images with large fluctuations. This work falls within the framework of developing adapted methods considering different surface structures in order to provide descriptors that are more precise
