Revegetation of an alpine area disturbed by excessive human activity along the Appalachian Trail was studied using the native species Arenaria groenlandica, Juncus trifidus, and Potentilla ...tridentata. Recruitment and mortality in populations of sown seed were recorded, and environmental parameters were measured in order to assess their impact on the population dynamics. The results showed similar patterns of establishment on hiker disturbed sites and on naturally open, undisturbed sites. Frost activity in the soil was the only identifiable cause of mortality. A fertilization treatment had no effect on establishment or survival. The species which had relatively rapid root growth had the highest rates of survival.
An ATP-like affinity labeling reagent, 5'-p-(fluorosulfonyl)benzoyladenosine (FSBA), was used to probe the MgATP-binding site of smooth muscle myosin light chain kinase from chicken gizzard (smMLCK) ...and its calmodulin (CaM) complex. Native smMLCK has an absolute requirement for the binding of the calcium complex of CaM for expression of its catalytic activity. FSBA reacted with smMLCK-CaM and with the CaM-free, inactive enzyme as well. Both reactions were dependent on time and FSBA concentration. Reaction was accompanied by the incorporation of covalently bound 14CFSBA into smMLCK protein at a molar ratio of approximately 1:1 in each case. p-(Fluorosulfonyl)benzoic acid, an analogue of FSBA lacking the adenosine targeting group, did not react at a significant rate with either form of smMLCK. Reaction of CaM-free and CaM-bound smMLCK with FSBA displayed saturation kinetics. The first-order rate constants for the conversion of the reversible, noncovalent enzyme-FSBA complex to form the irreversibly inhibited, covalently modified enzyme were similar for both smMLCK and smMLCK-CaM, 0.15 and 0.07 min-1, respectively. The concentrations of FSBA yielding the half-maximal rate of inactivation, KI, were essentially identical--0.65 and 0.64 mM, respectively--for smMLCK and smMLCK-CaM. MgATP, but not MgGTP or a substrate peptide, potently inhibited reaction with FSBA. Inhibition by MgATP was competitive. The measured inhibitory constant for MgATP was essentially the same--33 versus 34 microM--for both smMLCK and smMLCK-CaM. It therefore is concluded that the MgATP-binding site on smMLCK remains accessible and recognizable as such when the enzyme becomes inactivated upon dissociation of CaM.
Nous rapportons le cas d’une patiente de 49 ans chez qui a été découverte une tumeur endocrine développée sur un pancréas ectopique gastrique, traitée par résection chirurgicale. Le pancréas ...ectopique est une anomalie anatomique peu commune, mais probablement fréquemment méconnue car souvent asymptomatique. La transformation maligne est très rare et en règle sous forme d’adénocarcinome. L’apparition d’une tumeur endocrine sur pancréas ectopique est rarissime. À notre connaissance, quatre cas seulement ont été publiés, dont un seul avait une localisation gastrique similaire au cas que nous rapportons.
We report the case of a 49-year-old caucasian woman, in whom an endocrine tumor arising in gastric heterotopic pancreas was diagnosed. The patient was treated surgically with a gastric wedge resection. Heterotopic pancreas is a benign anatomic condition, probably widely underdiagnosed because usually asymptomatic. The malignant transformation of aberrant pancreas is very rare and almost always in adenocarcinoma. The endocrine tumors developped in heterotopic pancreas are exceedingly rare. Of our knowledge, only four cases have been published and only one case in the gastric location similar to this reported case.
Increasing interest is devoted to relationships between sugars (glucose, sucrose, fructose, raffinose…) and resistance of plants to biotic and abiotic stresses, resulting in the concept of “sweet ...immunity” or “sugar–enhanced defense”. The objective of the project USAGE (2012-2014) was to test the effect of spraying low doses of sugars on plants to control various bioagressors.The project brought together 43 trials (6 in orchards, 12 in vineyards, 25 with various vegetable crops) including 38 in field conditions. An additional objective was to evaluate the possibility to combine foliar application of sugars with reduced doses of pesticides while maintaining the quality of agricultural production. Some potential of sucrose and fructose was observed for the control of various parasites, at low to moderate pest pressures and I. Arnault et al. 2 Innovations Agronomiques 46 (2015), 1-10 on perennial crops (vineyards, arboriculture). Thus, the codling moth damage was reduced by 55% in organic orchards with both sucrose and fructose. Fructose sprays have reduced the amount of copperbased treatments used to control downy mildew in organic vineyards. The results contributed to the approval of sucrose as a basic substance (EU Regulations No. 916/2014 of the Committee on 24 August 2014).
Les sucres des plantes (glucose, fructose, saccharose, raffinose …) jouent un rôle fondamental dans la résistance de la plante à différents stress. On parle d’un nouveau concept de Sweet Immunity ou défense liée aux sucres. Le projet USAGE (2012-2014, ONEMA) a proposé de tester des applications foliaires d’infra-doses de sucres sur les plantes pour renforcer et accélérer le processus de Sweet Immunity sur différents couples de plante-bioagresseur. Le projet a regroupé 43 séries d’essais (6 en arboriculture, 12 en viticulture, 25 maraichage) dont 38 en conditions de productions. L’objectif générique était d’associer des sucres avec des doses réduites d’intrants tout en conservant la qualité de production agronomique. Les résultats, malgré les aléas d’expérimentations, ont permis d’observer un intérêt des applications de solutions de saccharose et de fructose pour le contrôle de différents bioagresseurs, lors de pressions parasitaires faibles à modérées et sur des cultures pérennes (vigne, arboriculture). Ainsi, les dégâts de carpocapse ont été réduits de 55% en arboriculture biologique avec le saccharose et le fructose. Dans les vignobles biologiques, les solutions de fructose ont permis de réduire les doses de cuivre contre le mildiou. Les résultats ont contribué à l’approbation du saccharose en substance de base (règlement d’exécution UE n° 916/2014 de la commission du 24 aout 2014).
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