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In the future management and sustainable use of boreal forests, it is crucial to consider the rate and strength of tree responses to an elevated water table and the concurrent oxygen limitations, especially in peatlands. We examined the response dynamics of 7-year-old Scots pine (Pinus sylvestris L.) seedlings to a 5-week waterlogging (WL) treatment during a growing season in a root lab (dasotron) experiment. WL took place after shoot elongation had ended but while growth of the trunk diameter was still in progress. Trunk sap flow and needle water potential started to decrease immediately after the onset of WL, while the first signs in needle gas exchange--seen as decreases in the potential efficiency of photosystem II, the rates of light-saturated net assimilation and transpiration, and increased needle respiration--were observed after 3 weeks of WL. New needles responded to WL more strongly than the old ones. Drainage with consequent re-oxygenation of the soil caused a further decrease in sap flow. We conclude that through negative feedback on transpiration and net photosynthesis, WL during the growing season is harmful for Scots pine, leading to potential growth losses or even dying of trees within a few weeks of WL. Key words: hypoxia, hydrology, peatland forestry, photosynthesis, sap flow. Pour l'amenagement futur et l'utilisation durable des forets boreales, il est essentiel de tenir compte du taux et de la robustesse de la reaction des arbres a l'elevation de la nappe phreatique et a l'appauvrissement simultane en oxygene, particulierement dans les tourbieres. Nous avons etudie la dynamique des reactions de semis de pin sylvestre (Pinus sylvestris L.) ages de 7 ans a un engorgement du sol d'une duree de 5 semaines au cours d'une saison de croissance lors d'une experience dans un laboratoire racinaire (dasotron). L'engorgement du sol est survenu apres que l'elongation des pousses eut ete completee mais pendant que la croissance en diametre du tronc etait toujours en cours. Le flux de seve dans le tronc et le potentiel hydrique des aiguilles ont commence a diminuer immediatement apres le debut de l'engorgement du sol, tandis que les premiers signes dans les echanges gazeux foliaires, visibles par la diminution de l'efficacite potentielle du photosysteme II, les taux de transpiration et d'assimilation nette a saturation lumineuse, ainsi que par l'augmentation de la respiration des aiguilles, ont ete observes apres 3 semaines d'engorgement du sol. Les nouvelles aiguilles ont reagi plus fortement a l'engorgement du sol que les vieilles aiguilles. Le drainage suivi de la reoxygenation du sol a cause une nouvelle diminution du flux de seve. Nous concluons que par l'intermediaire d'une retroaction negative sur la transpiration et la photosynthese nette, l'engorgement su sol durant la saison de croissance est nefaste pour le pin sylvestre et entraine des pertes potentielles de croissance ou meme la mort des arbres apres quelques semaines. [Traduit par la Redaction] Mots-cles: hypoxie, hydrologie, foresterie des tourbieres, photosynthese, flux de seve., Introduction Excess water, with consequently declined soil aeration, is one of the limiting factors in tree growth in the boreal zone, especially in the peatlands that extend to about 10% [...]

Equine asthma (EA) is an inflammatory disease of the lower airways driven by mediators released from cells. Extracellular vesicles (EVs) are vehicles for lipid mediators, which possess either pro-inflammatory or dual anti-inflammatory and pro-resolving functions. In this study, we investigated how the respiratory fatty acid (FA) profile reflects airway inflammatory status. The FA composition of bronchoalveolar lavage fluid (BALF), BALF supernatant, and bronchoalveolar EVs of healthy horses (n = 15) and horses with mild/moderate EA (n = 10) or severe EA (SEA, n = 5) was determined with gas chromatography and mass spectrometry. The FA profiles distinguished samples with different diagnoses in all sample types, yet they were insufficient to predict the health status of uncategorized samples. Different individual FAs were responsible for the discrimination of the diagnoses in different sample types. Particularly, in the EVs of SEA horses the proportions of palmitic acid (16:0) decreased and those of eicosapentaenoic acid (20:5n-3) increased, and all sample types of asthmatic horses had elevated dihomo-γ-linolenic acid (20:3n-6) proportions. The results suggest simultaneous pro-inflammatory and resolving actions of FAs and a potential role for EVs as vehicles for lipid mediators in asthma pathogenesis. EV lipid manifestations of EA can offer translational targets to study asthma pathophysiology and treatment options. [ABSTRACT FROM AUTHOR]

Scots pine (Pinus silvestris L.) cone and seed water contents were analyzed in two consecutive seasons during maturation stage in the autumn and in January and March before seed dispersal. Cones with different water contents were subjected to 2 h of freezing at -30°C, and seed viability and laboratory germination of seeds from individual cones after treatment were analyzed. Seed water content could be well predicted with the measurement of the cone water content, and the general relationship between these two could be described with a generalized logistic function. On average, the water content of cones was 5%-10% units higher than the seeds inside them. The higher the cone water content at the onset of freezing treatment, the higher the proportion of seeds with apparent damage (based on visual inspection of seeds using X-ray images) in that particular cone. High water content in cones also resulted in decreased germination after freezing treatment. The critical cone water content for 50% germination after freezing at -30°C was approximately 31.3% (fresh mass basis). This corresponds to 21.6% water content in seeds. Key words: freezing, maturation, cone moisture, X-ray, cone storage. La teneur en eau des cones et des graines de pin sylvestre (Pinus sylvestris L.) a ete analysee lors de deux saisons consecutives durant le stade de maturation a l'automne ainsi qu'en janvier et en mars avant la dispersion des graines. Des cones avec differentes teneurs en eau ont ete soumis au gel a -30°C durant deux heures et la viabilite ainsi que la germination des graines en laboratoire provenant de chaque cone ont ete analysees apres le traitement. La teneur en eau des graines pouvait etre correctement predite a partir des mesures de teneur en eau des cones et la relation generale entre les deux pouvait etre decrite avec une fonction logistique generalisee. En moyenne, la teneur en eau des cones etait 10%-15% plus elevee que celle des graines qu'ils contenaient. Plus la teneur en eau d'un cone etait elevee au debut du traitement de congelation, plus la proportion de graines avec des dommages apparents (d'apres une inspection visuelle des graines a partir d'images radiologiques) dans ce cone etait elevee. Une teneur en eau elevee dans les cones etait aussi synonyme d'une baisse de germination apres le traitement de congelation. La teneur en eau critique des cones pour un taux de germination de 50 % apres congelation a -30°C etait approximativement de 31,3 % (sur la base du poids frais). Cela correspond a une teneur en eau des graines de 21,6 %. [Traduit par la Redaction] Mots-cles: congelation, maturation, teneur en eau des cones, rayon X, entreposage des cones., Introduction Scots pine (Pinus sylvestris L.) is characterized by a 3 year reproductive cycle typical to many other pine species (Owens and Blake 1985). In the first year, reproductive buds [...]

Energy storage and growth are coordinated in response to nutrient status of animals. How nutrient‐regulated signaling pathways control these processes in vivo remains insufficiently understood. Here, we establish an atypical MAP kinase, ERK7, as an inhibitor of adiposity and growth in Drosophila. ERK7 mutant larvae display elevated triacylglycerol (TAG) stores and accelerated growth rate, while overexpressed ERK7 is sufficient to inhibit lipid storage and growth. ERK7 expression is elevated upon fasting and ERK7 mutant larvae display impaired survival during nutrient deprivation. ERK7 acts in the fat body, the insect counterpart of liver and adipose tissue, where it controls the subcellular localization of chromatin‐binding protein PWP1, a growth‐promoting downstream effector of mTOR. PWP1 maintains the expression of sugarbabe, encoding a lipogenic Gli‐similar family transcription factor. Both PWP1 and Sugarbabe are necessary for the increased growth and adiposity phenotypes of ERK7 loss‐of‐function animals. In conclusion, ERK7 is an anti‐anabolic kinase that inhibits lipid storage and growth while promoting survival on fasting conditions. SYNOPSIS: This study demonstrates that the atypical MAP kinase ERK7 reduces adiposity and inhibits growth of Drosophila larvae. ERK7 acts in the fat body by inhibiting chromatin binding protein PWP1 and transcription factor Sugarbabe. ERK7 depletion in the fly promotes adiposity and growth while impairing survival during fasting.ERK7 depletion interferes with the subcellular localization of chromatin binding protein PWP1 in the fat body.PWP1 promotes TAG storage and growth downstream of ERK7.PWP1 depletion reduces the expression of transcription factor Sugarbabe to promote lipid storage and growth. [ABSTRACT FROM AUTHOR]

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Long-term effects of elevated CO2 and O3 concentrations on gene expression in silver birch ( Betula pendula Roth) leaves were studied during the end of the growing season. Two birch genotypes, clones 4 and 80, with different ozone growth responses, were exposed to 2× ambient CO2 and/or O3 in open-top chambers (OTCs). Microarray analyses were performed after 2 years of exposure, and the transcriptional profiles were compared to key physiological characteristics during leaf senescence. There were genotypic differences in the responses to CO2 and O3. Clone 80 exhibited greater transcriptional response and capacity to alter metabolism, resulting in better stress tolerance. The gene expression patterns of birch leaves indicated contrasting responses of senescence-related genes to elevated CO2 and O3. Elevated CO2 delayed leaf senescence and reduced associated transcriptional changes, whereas elevated O3 advanced leaf senescence because of increased oxidative stress. The combined treatment demonstrated that elevated CO2 only temporarily alleviated the negative effects of O3. Gene expression data alone were insufficient to explain the O3 response in birch, and additional physiological and biochemical data were required to understand the true O3 sensitivity of these clones. [ABSTRACT FROM AUTHOR]

Gene expression responses of paper birch (Betula papyrifera) leaves to elevated concentrations of CO2 and O3 were studied with microarray analyses from three time points during the summer of 2004 at Aspen FACE. Microarray data were analyzed with clustering techniques, self-organizing maps, K-means clustering and Sammon''s mappings, to detect similar gene expression patterns within sampling times and treatments. Most of the alterations in gene expression were caused by O3, alone or in combination with CO2. O3 induced defensive reactions to oxidative stress and earlier leaf senescence, seen as decreased expression of photosynthesis- and carbon fixation-related genes, and increased expression of senescence-associated genes. The effects of elevated CO2 reflected surplus of carbon that was directed to synthesis of secondary compounds. The combined CO2 +O3 treatment resulted in differential gene expression than with individual gas treatments or in changes similar to O3 treatment, indicating that CO2 cannot totally alleviate the harmful effects of O3. [Copyright &y& Elsevier]

In the future management and sustainable use of boreal forests, it is crucial to consider the rate and strength of tree responses to an elevated water table and the concurrent oxygen limitations, especially in peatlands. We examined the response dynamics of 7-year-old Scots pine ( Pinus sylvestris L.) seedlings to a 5-week waterlogging (WL) treatment during a growing season in a root lab (dasotron) experiment. WL took place after shoot elongation had ended but while growth of the trunk diameter was still in progress. Trunk sap flow and needle water potential started to decrease immediately after the onset of WL, while the first signs in needle gas exchange - seen as decreases in the potential efficiency of photosystem II, the rates of light-saturated net assimilation and transpiration, and increased needle respiration - were observed after 3 weeks of WL. New needles responded to WL more strongly than the old ones. Drainage with consequent re-oxygenation of the soil caused a further decrease in sap flow. We conclude that through negative feedback on transpiration and net photosynthesis, WL during the growing season is harmful for Scots pine, leading to potential growth losses or even dying of trees within a few weeks of WL. [ABSTRACT FROM AUTHOR]

Objective: Chronic inflammatory diseases, like Systemic Lupus Erythematosus (SLE), carry an increased risk for atherosclerosis and cardiovascular events, accompanied by impairment of atheroprotective properties of high-density lipoprotein (HDL). In SLE, serum BAFF (B cell-activating factor), a cytokine implicated in disease progression, has been correlated with subclinical atherosclerosis. We investigated the impact of treatment with belimumab -an anti-BAFF monoclonal antibody- on HDL atheroprotective properties and composition in SLE patients., Methods: Serum samples were collected from 35 SLE patients with active disease despite conventional therapy, before and after 6-month add-on treatment with belimumab, and 26 matched healthy individuals. We measured cholesterol efflux and antioxidant capacities, paraoxonase-1 activity, serum amyloid A1, myeloperoxidase and lipid peroxidation product levels of HDL. LC-MS/MS was performed to analyze the HDL lipidome., Results: Following treatment with belimumab, cholesterol efflux and antioxidant capacities of HDL were significantly increased in SLE patients and restored to levels of controls. HDL-associated paraoxonase-1 activity was also increased, whereas lipid peroxidation products were decreased following treatment. HDL cholesterol efflux and antioxidant capacities correlated negatively with the disease activity. Changes were noted in the HDL lipidome of SLE patients following belimumab treatment, as well as between SLE patients and healthy individuals, and specific changes in lipid species correlated with functional parameters of HDL., Conclusions: HDL of SLE patients with active disease displays impaired atheroprotective properties accompanied by distinct lipidomic signature compared with controls. Belimumab treatment may improve the HDL atheroprotective properties and modify the HDL lipidomic signature in SLE patients, thus potentially mitigating atherosclerosis development., (© The Author(s) 2024. Published by Oxford University Press on behalf of the British Society for Rheumatology.)