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Pour obtenir un aperçu spécifique des rôles que les micro-organismes pourraient jouer dans la stéatose hépatique non alcoolique (NAFLD), certaines bactéries intestinales et lactiques et une levure (Anaerostipes caccae, Bacteroides thetaiotaomicron, Bifidobacterium longum, Enterococcus fecalis, Escherichia coli, Lactobacillus acidophilus, Lactobacillus fermentum, Lactobacillus plantarum, Weissella confusa, Saccharomyces cerevisiae) ont été caractérisées par une chromatographie liquide haute performance pour la production d'éthanol lorsqu'elles sont cultivées sur différents glucides : hexoses (glucose et fructose), pentoses (arabinose et ribose), disaccharides (lactose et lactulose) et inuline. Les quantités les plus élevées d'éthanol ont été produites par S. cerevisiae, L. fermentum et W. confusa sur le glucose et par S. cerevisiae et W. confusa sur le fructose. En raison de la mannitol-déshydrogénase exprimée dans L. fermentum, la production d'éthanol sur le fructose a été significativement réduite (P < 0,05). Le pyruvate et le citrate, deux accepteurs d'électrons potentiels pour la régénération du NAD+/NADP+, ont considérablement réduit la production d'éthanol avec de l'acétate produit à la place dans L. fermentum cultivé sur glucose et W. confusa cultivé sur glucose et fructose, respectivement. Dans les boues fécales préparées à partir des matières fécales de quatre volontaires en surpoids, on a constaté que l'éthanol était produit lors de l'ajout de fructose. L'ajout d'A. caccae, L. acidophilus, L. fermentum, ainsi que de citrate et de pyruvate, respectivement, a aboli la production d'éthanol. Cependant, l'ajout de W. confusa a entraîné une augmentation significative (P < 0,05) de la production d'éthanol. Ces résultats indiquent que des micro-organismes comme W. confusa, une bactérie lactique hétéro-fermentaire, négative à la mannitol-déshydrogénase, peuvent favoriser la NAFLD par l'éthanol produit à partir de la fermentation du sucre, tandis que d'autres bactéries intestinales et des bactéries lactiques homo- et hétéro-fermentaires mais positives à la mannitol-déshydrogénase peuvent ne pas favoriser la NAFLD. En outre, nos études indiquent que les facteurs alimentaires interférant avec le microbiote gastro-intestinal et le métabolisme microbien peuvent être importants dans la prévention ou la promotion de la NAFLD. Para obtener información específica sobre los roles que podrían desempeñar los microorganismos en la enfermedad del hígado graso no alcohólico (NAFLD, por sus siglas en inglés), algunas bacterias intestinales y del ácido láctico y una levadura (Anaerostipes caccae, Bacteroides thetaiotaomicron, Bifidobacterium longum, Enterococcus fecalis, Escherichia coli, Lactobacillus acidophilus, Lactobacillus fermentum, Lactobacillus plantarum, Weissella confusa, Saccharomyces cerevisiae) se caracterizaron por cromatografía líquida de alto rendimiento para la producción de etanol cuando se cultivaron en diferentes carbohidratos: hexosas (glucosa y fructosa), pentosas (arabinosa y ribosa), disacáridos (lactosa y lactulosa) e inulina. Las cantidades más altas de etanol fueron producidas por S. cerevisiae, L. fermentum y W. confusa en glucosa y por S. cerevisiae y W. confusa en fructosa. Debido a la manitol-deshidrogenasa expresada en L. fermentum, la producción de etanol en fructosa se redujo significativamente (P < 0.05). El piruvato y el citrato, dos aceptores de electrones potenciales para la regeneración de NAD+/NADP+, redujeron drásticamente la producción de etanol con acetato producido en su lugar en L. fermentum cultivado en glucosa y W. confusa cultivado en glucosa y fructosa, respectivamente. En suspensiones fecales preparadas a partir de heces de cuatro voluntarios con sobrepeso, se encontró que el etanol se producía tras la adición de fructosa. La adición de A. caccae, L. acidophilus, L. fermentum, así como citrato y piruvato, respectivamente, abolió la producción de etanol. Sin embargo, la adición de W. confusa resultó en un aumento significativo (P < 0.05) de la producción de etanol. Estos resultados indican que microorganismos como W. confusa, una bacteria de ácido láctico hetero-fermentativa, negativa para manitol-deshidrogenasa, pueden promover NAFLD a través del etanol producido a partir de la fermentación de azúcar, mientras que otras bacterias intestinales y bacterias de ácido láctico homo- y hetero-fermentativas pero positivas para manitol-deshidrogenasa pueden no promover NAFLD. Además, nuestros estudios indican que los factores dietéticos que interfieren con la microbiota gastrointestinal y el metabolismo microbiano pueden ser importantes para prevenir o promover la EHGNA. To gain some specific insight into the roles microorganisms might play in non-alcoholic fatty liver disease (NAFLD), some intestinal and lactic acid bacteria and one yeast (Anaerostipes caccae, Bacteroides thetaiotaomicron, Bifidobacterium longum, Enterococcus fecalis, Escherichia coli, Lactobacillus acidophilus, Lactobacillus fermentum, Lactobacillus plantarum, Weissella confusa, Saccharomyces cerevisiae) were characterized by high performance liquid chromatography for production of ethanol when grown on different carbohydrates: hexoses (glucose and fructose), pentoses (arabinose and ribose), disaccharides (lactose and lactulose), and inulin. Highest amounts of ethanol were produced by S. cerevisiae, L. fermentum and W. confusa on glucose and by S. cerevisiae and W. confusa on fructose. Due to mannitol-dehydrogenase expressed in L. fermentum, ethanol production on fructose was significantly (P < 0.05) reduced. Pyruvate and citrate, two potential electron acceptors for regeneration of NAD+/NADP+, drastically reduced ethanol production with acetate produced instead in L. fermentum grown on glucose and W. confusa grown on glucose and fructose, respectively. In fecal slurries prepared from feces of four overweight volunteers, ethanol was found to be produced upon addition of fructose. Addition of A. caccae, L. acidophilus, L. fermentum, as well as citrate and pyruvate, respectively, abolished ethanol production. However, addition of W. confusa resulted in significantly (P < 0.05) increased production of ethanol. These results indicate that microorganisms like W. confusa, a hetero-fermentative, mannitol-dehydrogenase negative lactic acid bacterium, may promote NAFLD through ethanol produced from sugar fermentation, while other intestinal bacteria and homo- and hetero-fermentative but mannitol-dehydrogenase positive lactic acid bacteria may not promote NAFLD. Also, our studies indicate that dietary factors interfering with gastrointestinal microbiota and microbial metabolism may be important in preventing or promoting NAFLD. لاكتساب بعض الأفكار المحددة حول الأدوار التي قد تلعبها الكائنات الحية الدقيقة في مرض الكبد الدهني غير الكحولي (NAFLD)، تميزت بعض بكتيريا حمض الأمعاء واللاكتيك وخميرة واحدة (Anaerostipes caccae، Bacteroides thetaiotaomicron، Bifidobacterium longum، Enterococcus fecalis، Escherichia coli، Lactobacillus acidophilus، Lactobacillus fermentum، Lactobacillus plantarum، Weissella confusa، Saccharomyces cerevisiae) بتصوير سائل عالي الأداء لإنتاج الإيثانول عند زراعته على كربوهيدرات مختلفة: hexoses (الجلوكوز والفركتوز)، pentoses (الأرابينوز والريبوز)، disaccharides (اللاكتوز واللاكتولوز)، و inulin. تم إنتاج أعلى كميات من الإيثانول بواسطة S. cerevisiae و L. fermentum و W. confusa على الجلوكوز و S. cerevisiae و W. confusa على الفركتوز. بسبب نازعة هيدروجين المانيتول المعبر عنها في L. fermentum، انخفض إنتاج الإيثانول على الفركتوز بشكل كبير (P < 0.05). قلل البيروفات والسيترات، وهما مستقبلان محتملان للإلكترون لتجديد NAD +/NADP+، بشكل كبير من إنتاج الإيثانول مع الأسيتات المنتجة بدلاً من ذلك في L. fermentum المزروع على الجلوكوز و W. confusa المزروع على الجلوكوز والفركتوز، على التوالي. في الملاط البرازي الذي تم تحضيره من براز أربعة متطوعين يعانون من زيادة الوزن، وجد أن الإيثانول يتم إنتاجه عند إضافة الفركتوز. إضافة A. caccae، L. acidophilus، L. fermentum، وكذلك السترات والبيروفات، على التوالي، ألغت إنتاج الإيثانول. ومع ذلك، أدت إضافة W. confusa إلى زيادة كبيرة في إنتاج الإيثانول (P < 0.05). تشير هذه النتائج إلى أن الكائنات الحية الدقيقة مثل W. confusa، وهي بكتيريا حمض اللاكتيك السلبية غير المتجانسة، قد تعزز NAFLD من خلال الإيثانول المنتج من تخمير السكر، في حين أن البكتيريا المعوية الأخرى وبكتيريا حمض اللاكتيك الإيجابية غير المتجانسة ولكن غير المتجانسة قد لا تعزز NAFLD. أيضًا، تشير دراساتنا إلى أن العوامل الغذائية التي تتداخل مع الكائنات الحية الدقيقة في الجهاز الهضمي والتمثيل الغذائي الميكروبي قد تكون مهمة في منع أو تعزيز NAFLD.

Abstract. Regional land carbon budgets provide insights on the spatial distribution of the land uptake of atmospheric carbon dioxide, and can be used to evaluate carbon cycle models and to define baselines for land-based additional mitigation efforts. The scientific community has been involved in providing observation-based estimates of regional carbon budgets either by downscaling atmospheric CO2 observations into surface fluxes with atmospheric inversions, by using inventories of carbon stock changes in terrestrial ecosystems, by upscaling local field observations such as flux towers with gridded climate and remote sensing fields or by integrating data-driven or process-oriented terrestrial carbon cycle models. The first coordinated attempt to collect regional carbon budgets for nine regions covering the entire globe in the RECCAP-1 project has delivered estimates for the decade 2000–2009, but these budgets were not comparable between regions, due to different definitions and component fluxes reported or omitted. The recent recognition of lateral fluxes of carbon by human activities and rivers, that connect CO2 uptake in one area with its release in another also requires better definition and protocols to reach harmonized regional budgets that can be summed up to the globe and compared with the atmospheric CO2 growth rate and inversion results. In this study, for the international initiative RECCAP-2 coordinated by the Global Carbon Project, which aims as an update of regional carbon budgets over the last two decades based on observations, for 10 regions covering the globe, with a better harmonization that the precursor project, we provide recommendations for using atmospheric inversions results to match bottom-up carbon accounting and models, and we define the different component fluxes of the net land atmosphere carbon exchange that should be reported by each research group in charge of each region. Special attention is given to lateral fluxes, inland water fluxes and land use fluxes.

Seasonal rhythms in energy balance are well documented across temperate and equatorial zones animals. The long-term regulated changes in seasonal physiology consists of a rheostatic system that is essential to successful time annual cycles in reproduction, hibernation, torpor, and migration. Most animals use the annual change in photoperiod as a reliable and robust environmental cue to entrain endogenous (i.e. circannual) rhythms. Research over the past few decades has predominantly examined the role of first order neuroendocrine peptides for the rheostatic changes in energy balance. These anorexigenic and orexigenic neuropeptides in the arcuate nucleus include neuropeptide y (Npy), agouti-related peptide (Agrp), cocaine and amphetamine related transcript (Cart) and pro-opiomelanocortin (Pomc). Recent studies also indicate that VGF nerve growth factor inducible (Vgf) in the arcuate nucleus is involved in the seasonal regulation of energy balance. In situ hybridization, qPCR and RNA-sequencing studies have identified that Pomc expression across fish, avian and mammalian species, is a neuroendocrine marker that reflects seasonal energetic states. Here we highlight that long-term changes in arcuate Pomc and Vgf expression is conserved across species and may provide rheostatic regulation of seasonal energy balance.

AbstractThe co‐occurrence of chronic pain and alcohol use disorders (AUDs) involves complex interactions between genetic and neurophysiological aspects, and the research has reported mixed findings when they both co‐occur. There is also an indication of a gender‐dependent effect; males are more likely to use alcohol to cope with chronic pain problems than females. Recently, a new conceptualization has emerged, proposing that the negative affective component of pain drives and maintains alcohol‐related behaviors. We studied in a longitudinal fashion alterations in alcohol drinking patterns and pain thresholds in a mouse model of chronic neuropathic pain in a sex‐dependent manner. Following partial denervation (spared nerve injury [SNI]), stimulus‐evoked pain responses were measured before chronic alcohol consumption, during drinking, during a deprivation phase, and following an episode of excessive drinking. During the course of alcohol drinking, we observed pronounced sex differences in pain thresholds. Male mice showed a strong increase in pain thresholds, suggesting an analgesic effect induced by alcohol over time, an effect that was not observed in female mice. SNI mice did not differ from sham‐operated controls in baseline alcohol consumption. However, following a deprivation phase and the reintroduction of ethanol, male SNI mice but not female mice showed more pronounced excessive drinking than controls. Finally, we observed decreased central ethanol sensitivity in male SNI mice but not in females. Together with our finding, that ethanol is able to decrease a pain‐induced negative affective memory we come to following conclusion. We propose that a lower sensitivity to the intoxicating effects of alcohol together with the ability of alcohol to reduce the negative affective component of pain may explain the higher co‐occurrence of AUD in male chronic pain patients.

The fast decay in PEM fuel cells of a highly active, high performance, but unstable Fe/N/C catalyst like our NC_Ar + NH3 follows a chemical, not an electrochemical, demetallation mechanism for its ORR active FeN4 sites in the catalyst micropores.

Although soils provide social and ecological services which are of a clearly transnational dimension, the management of soils needs to be addressed locally. Thus, an appropriate - or better, effective governance for sustainable soil management at national level is essential. This chapter provides some fundamental recommendations for an effective governance based on legal studies from several African countries, namely Cameroon, Kenya and Zambia.

Global warming is enabling many plant species to expand their range to higher latitudes and altitudes, where they may suffer less from natural aboveground and belowground enemies. Reduced control by natural enemies can enable climate warming‐induced range expanders to gain an advantage in competition with natives and become disproportionally abundant in their new range. However, so far studies have only examined individual growth of range expanders, which have common congeneric plant species in their new range. Thus it is not known how general is this reduced effect of above‐ and belowground enemies and how it operates in communities, where multiple plant species also interact with each other. Here we show that range‐expanding plant species with and without congenerics in the invaded habitats differ in their ecological interactions in the new range. In a community‐level experiment, range‐expanding plant species, both with and without congenerics, suppressed the growth of a herbivore. However, only range expanders without congenerics reduced biomass production of the native plant species. In the present study, range expanders without congenerics allocated more biomass aboveground compared to native plant species, which can explain their competitive advantage. Competitive interaction and also biomass allocation of native plants and their congeneric range expanders were similar. Our results highlight that information about species phylogenetic relatedness with native flora can be crucial for improving predictions about the consequences of climate warming‐induced range expansions.

We present the determination of the alkaloid hordenine and its forensic relevance as a qualitative and quantitative marker for beer consumption. A simple, rapid and sensitive ultra-performance liquid chromatography (UPLC)-tandem mass spectrometry (MS/MS) method for the determination of hordenine in human serum samples was developed and validated. The application was tested with serum samples after enzymatic cleavage. After addition of the synthesized internal standard hordenine-D 4, a liquid-liquid extraction with dichloromethane and diethyl ether was performed. Chromatographic separation was conducted with a Waters Acquity® UPLC system with gradient elution on an Agilent Eclipse XDB-C18 column (4.6 mm × 150 mm, 5-μm particle size). For quantification, a Waters Acquity® TQ detector (version SNC 627) with a positive electrospray ionization probe and multiple reaction monitoring mode was used. A flow rate of 0.4 ml/min was applied. The retention time for both the analyte and the internal standard was 3.67 min. Linearity was demonstrated from 0.2 to 16 ng/ml (R(2) > 0.999). The lower limit of quantification was 0.3 ng/ml in serum. Matrix effects and extraction recoveries for low and high concentrations were within acceptable limits of 75-125% and 50%, respectively. To the best of our knowledge there is no corresponding method for the determination of hordenine by UPLC-MS/MS in serum. By our drinking studies we demonstrate that beer consumption leads to detectable hordenine concentrations in serum and observed a linear elimination of total hordenine correlating to blood alcohol concentration, which shows that hordenine can be used as a reliable qualitative and quantitative marker for beer consumption. The validated method was successfully applied to serum from actual forensic cases.

Human diamine oxidase (hDAO, EC 1.4.3.22) is the key enzyme in the degradation of extracellular histamine. Consumption of alcohol is a known trigger of mast cell degranulation in patients with mast cell activation syndrome. Ethanol may also interfere with enzymatic histamine degradation, but reports on the effects on DAO activity are controversial. There are also conflicting reports whether disulfiram, an FDA-approved agent in the treatment of alcohol dependence, inhibits DAO. We therefore investigated the inhibitory potential of ethanol and disulfiram and their metabolites on recombinant human DAO (rhDAO) in three different assay systems. Relevant concentrations of ethanol, acetaldehyde, and acetate did not inhibit rhDAO activity in an in vitro assay system using horseradish peroxidase (HRP) -mediated luminol oxidation. The aldehyde dehydrogenase (ALDH; EC 1.2.1.3) inhibitors cyanamide and its dimer dicyanamide also had no effect on DAO activity. In one assay system, the irreversible ALDH inhibitor disulfiram and its main metabolite diethyldithiocarbamate seemed to inhibit DAO activity. However, the decreased product formation was not due to a direct block of DAO activity but resulted from inhibition of peroxidase employed in the coupled system. Our in vitro data do not support a direct blocking effect of ethanol, disulfiram, and their metabolites on DAO activity in vivo.