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Sleep deprivation (SD) has been associated with a plethora of severe pathophysiological syndromes, including gut damage, which recently has been elucidated as an outcome of the accumulation of reactive oxygen species (ROS). However, the spatiotemporal analysis conducted in this study has intriguingly shown that specific events cause harmful damage to the gut, particularly to goblet cells, before the accumulation of lethal ROS. Transcriptomic and metabolomic analyses have identified significant enrichment of metabolites related to ferroptosis in mice suffering from SD. Further analysis revealed that melatonin could rescue the ferroptotic damage in mice by suppressing lipid peroxidation associated with ALOX15 signaling. ALOX15 knockout protected the mice from the serious damage caused by SD‐associated ferroptosis. These findings suggest that melatonin and ferroptosis could be targets to prevent devastating gut damage in animals exposed to SD. To sum up, this study is the first report that proposes a noncanonical modulation in SD‐induced gut damage via ferroptosis with a clearly elucidated mechanism and highlights the active role of melatonin as a potential target to maximally sustain the state during SD. [ABSTRACT FROM AUTHOR]

Two new aryltetralin-type lignans (1-2) were isolated from the dichloromethane fraction of 95% ethanol extract of Camellia oleifera fruit husk. Their structures were elucidated on the basis of spectroscopic analysis, and the absolute configurations of compounds 1-2 were determined by the comparison of measured ECD curves with the quantum chemical calculated ones. The new compounds were tested for their antioxidant activities and cytotoxicity against three human cancer cell lines (Huh-7, H460 and MCF-7). While compounds 1 and 2 only showed slight DPPH radical scavenging activities with the IC50 values of 38.68 ± 5.02 and 56.62 ± 1.49 μM, respectively. [ABSTRACT FROM AUTHOR]

Exponential fertilization has been shown to be a useful technique for improving seedling quality during nursery production. In this study, we evaluated (i) the impact of exponential vs. conventional fertilization on trembling aspen (Populus tremuloides Michx.) and white spruce (Picea glauca (Moench) Voss) seedlings during nursery production and (ii) the growth performance and nitrogen (N) utilization of those seedlings in response to foxtail barley (Hordeum jubatum L.) competition after the transplantation of seedlings in a greenhouse experiment. Exponential fertilization with an application rate higher than the conventional fertilization increased the internal N reserve in trembling aspen and white spruce seedlings during nursery production and also increased new leaf, new stem, and old stem biomass and N retranslocation rates in trembling aspen seedlings but not in white spruce seedlings after transplantation. Foxtail barley competition decreased N concentrations in seedlings and soil N uptake by the seedlings; however, increased N retranslocation rates with foxtail barley competition were observed in white spruce seedlings but not in trembling aspen seedlings. Our results suggest that the growth performance of seedlings was improved by N loading, whereas the impact of vegetation management was species specific. Key words: exponential fertilization, internal N reserve, N-loaded seedling, net N retranslocation rate, vegetation competition. La fertilisation exponentielle s'est averee utile pour ameliorer la qualite des semis lors de la production en pepiniere. Dans cette etude, nous avons evalue (i) l'impact de la fertilisation exponentielle vs conventionnelle sur les semis de peuplier faux-tremble (Populus tremuloides Michx.) et d'epicea blanc (Picea glauca (Moench) Voss) lors de la production en pepiniere, et (ii) la croissance de ces semis et leur utilisation de N en reaction a la competition de l'orge queue-d'ecureuil (Hordeum jubatum L.) apres les avoir transplantes en serre suivant un dispositif experimental. La fertilisation exponentielle, dont le taux d'application est plus eleve que la fertilisation conventionnelle, a augmente les reserves internes de N chez les semis de peuplier faux- tremble et d'epicea blanc durant la production en pepiniere et a augmente la biomasse des nouvelles feuilles, des nouvelles et des vieilles tiges ainsi que le taux de retranslocation de N apres la transplantation chez les semis de peuplier faux-tremble mais pas chez les semis d'epicea blanc. La competition de l'orge queue-d'ecureuil a reduit les concentrations de N dans les semis et l'absorption de N dans le sol par les semis; cependant, en presence de l'orge queue-d'ecureuil une augmentation du taux de retranslocation de N a ete observee chez les semis d'epicea blanc mais pas chez les semis de peuplier faux-tremble. Nos resultats indiquent que la croissance des semis a ete amelioree par une surcharge de N tandis que l'impact de la maitrise de la vegetation dependait de chaque espece. [Traduit par la Redaction] Mots-cles : fertilisation exponentielle, reserves internes de N, semis surcharges en N, taux net de retranslocation, competition de la vegetation., Introduction Vegetation management is one of the most critical silvicultural practices for maximizing postplanting tree seedling survival and growth during the early establishment phase of plantations (Lowery et al. 1993; [...]

Chronic nitrogen (N) and (or) sulfur (S) deposition to boreal forests in the Athabasca oil sands region (AOSR) in Alberta, Canada, has been caused by oil sands mining and extraction/upgrading activities. It is important that we understand the response of microbial community function to chronic N and S deposition as microbial populations mediate soil carbon (C) and N cycles and affect ecosystem resilience. To evaluate the impact of N and (or) S deposition on soil microbial community functions, we conducted a simulated N and S deposition experiment in a boreal mixedwood forest with the following four treatments: control (CK), N addition (+N, 30 kg N*[ha.sup.-1] as N[H.sub.4]N[O.sub.3]), S addition (+S, 30 kg S*[ha.sup.-1] as NaS[O.sub.4]), and N plus S addition (+NS, 30 kg N*[ha.sup.-1] + 30 kg S*[ha.sup.-1]), from 2006 to 2010. Nitrogen and (or) S deposition did not change soil organic carbon, total N, dissolved organic C and N, or soil microbial biomass C and N. Soil microbial community-level physiological profiles, however, were strongly affected by 5 years of N and (or) S addition. Soil β-glucosidase activity in the +NS treatment was greater than that in the +S treatment, and S addition decreased soil arylsulfatase; however, urease and dehydrogenase activities were not affected by the simulated N and (or) S deposition. Our data suggested that N and (or) S deposition strongly affected soil microbial community functions and enzymatic activities without changing soil microbial biomass in the studied boreal forest. Resume: Les depots chroniques d'azote (N) et de soufre (S) en foret boreale dans la region des sables bitumineux de l'Athabasca, en Alberta au Canada, ont ete causes par l'exploitation miniere et les activites d'extraction et de valorisation des sables bitumineux. Il est important de comprendre la reponse des fonctions de la communaute microbienne face aux depots chroniques de N et de S etant donne que les populations microbiennes interviennent dans les cycles du carbone (C) et de N dans le sol et ont un impact sur la resilience des ecosystemes. Pour evaluer l'impact des depots de N et de S sur les fonctions de la communaute microbienne du sol, nous avons realise une experience de depots simules de N et de S dans une foret boreale melangee. Nous avons applique les quatre traitements suivants: temoin (CK), apport de N (+N, 30 kg N*[ha.sup.-1] sous forme de N[H.sub.4]N[O.sub.3]), apport de S (+S, 30 kg S*[ha.sup.-1] sous forme de NaS[O.sub.4]), et apport de N plus S (+NS, 30 kg N*[ha.sup.-1] + 30 kg S*[ha.sup.-1]), de 2006 a 2010. Les depots de N et de S, seuls ou combines, n'ont pas modifie le C organique, le N total, le C et le N organiques dissouts dans le sol, ni le C et le N de la biomasse microbienne du sol. Cependant, les profils physiologiques a l'echelle de la communaute microbienne du sol etaient fortement affectes apres cinq ans d'apports de N et de S, seuls ou combines. L'activite de la β-glucosidase dans le sol du traitement +NS etait plus elevee que dans le traitement +S et l'apport de S a reduit l'activite de l'arylsulfatase. Cependant, l'activite de l'urease et celle de la deshydrogenase n'ont pas ete affectees par les depots simules de N et de S, seuls ou combines. Nos donnees indiquent que les depots de N et de S ont fortement affectes les fonctions de la communaute microbienne du sol et l'activite enzymatique sans modifier la biomasse microbienne dans la foret boreale que nous avons etudiee. [Traduit par la Redaction], Introduction Nitrogen oxides (N[O.sub.x]) and sulfur dioxide (S[O.sub.2]) emissions from fossil fuel combustion and other anthropogenic activities have caused elevated levels of N and S deposition in industrialized regions (Granberg [...]