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Abstract: The ecological plasticity of Vaccinium membranaceum (Ericaceae) to grow from valley bottoms to alpine habitats allowed us to test if fungal community structure varies along an elevation gradient in east-central British Columbia. Using the shrub as an independent variable, and plant and soil features along the gradient to model a changing climate, communities of root-associated fungi were investigated. The colonized roots from 40 individuals were examined using culture-dependent sequencing and ARISA (automated ribosomal intergenic spacer analysis). Our results demonstrated that high elevation fungal communities, characterised by Rhizoscyphus ericae, differ from lower elevation communities, where Phialocephala fortinii was the most frequently isolated fungus. Co-occurrence analysis indicated that, overall, fungi tended to occur together more often than would be expected by chance. At the scale of the individual host plant, facilitation may play a more important role than competition in shaping fungal communities in these ecosystems. [Copyright &y& Elsevier]

Abstract: Phylogenetic analyses of ITS and β-tubulin DNA sequences for 30 Puccinia striiformis specimens from wide geographic and host ranges revealed four strongly supported monophyletic lineages. Based on comparisons of morphological characteristics, and after consideration of previous classifications, the lineages were recognized as P. striiformis sensu stricto, Puccinia pseudostriiformis, Puccinia striiformoides and one new species, Puccinia gansensis. A new series (Puccinia Series Striiformis) was erected to accommodate this strongly supported monophyletic group of four species within Puccinia. Expanded descriptions, illustrations and a tabular identification key are provided. The morphological differences among species are subtle but host association and combinations of other characters can be used successfully for identification. Puccinia striiformis s.str. has the widest host range, within the tribe Triticeae (Aegilops, Elymus, Hordeum and Triticum) but it is less diverse than previously documented. The other three species are restricted to single genera in Poeae (P. pseudostriiformis on Poa; P. striiformoides on Dactylis) or Stipeae (P. gansensis on Achnatherum). Urediniospore size and surface echinulation, especially as seen by SEM, germ pore number, shape of uredinial paraphyses, and teliospore hilum width were the main features used to differentiate species. Relying solely on the symptom of linearly aligned uredinia on chlorotic stripes on leaves, from which the common name “stripe rust” was derived, is not recommended because sori of other leaf rust species may also form in a linear series. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Six multi-target compounds with potential anti-AD properties have been studied. • BACE 1 inhibitory assay shows moderate to good activity for some of them. • Theoretical docking studies provide insights on the compound-protein interaction. • The compounds bind Cu2+ selectively over other biologically relevant metal ions. • The multi-target compounds are excellent antioxidant agents. • ThT and turbidity assays reveal promising anti-amyloidogenic properties. Abstract The lack of any effective therapy along with the aging world population anticipates a growth of the worldwide incidence of Alzheimer’s disease (AD) to more than 100 million cases by 2050. Accumulation of extracellular amyloid-β (Aβ) plaques, intracellular tangles in the brain, and formation of reactive oxygen species (ROS) are the major hallmarks of the disease. In the amyloidogenic process, a β-secretase, known as BACE 1, plays a fundamental role in the production of Aβ fragments, and therefore, inhibition of such enzymes represents a major strategy for the rational design of anti-AD drugs. In this work, a series of four multi-target compounds (1 – 4), inspired by previously described ionophoric polyphenols, have been synthesized and studied. These compounds have been designed to target important aspects of AD, including BACE 1 enzymatic activity, Aβ aggregation, toxic concentrations of Cu2+ metal ions and/or ROS production. Two other compounds (5 and 6), previously reported by some of us as antimalarial agents, have also been studied because of their potential as multi-target species against AD. Interestingly, compounds 3 and 5 showed moderate to good ability to inhibit BACE 1 enzymatic activity in a FRET assay, with IC 50 ′s in the low micromolar range (4.4 ± 0.3 and 1.7 ± 0.3 μM, respectively), comparable to other multi-target species, and showing that the observed activity was in part due to a competitive binding of the compounds at the active site of the enzyme. Theoretical docking calculations overall agreed with FRET assay results, displaying the strongest binding affinities for 3 and 5 at the active site of the enzyme. In addition, all compounds selectively interacted with Cu2+ metal ions forming 2:1 complexes, inhibited the production of Aβ-Cu2+ catalyzed hydroxyl radicals up to a ∼100% extent, and scavenged AAPH-induced peroxyl radical species comparably to resveratrol, a compound used as reference in this work. Our results also show good anti-amyloidogenic ability: compounds 1 – 6 inhibited both the Cu2+-induced and self-induced Aβ(1–40) fibril aggregation to an extent that ranged from 31% to 77%, while they disaggregated pre-formed Aβ(1–40) mature fibrils up to a 37% and a 69% extent in absence and presence of Cu2+, respectively. Cytotoxicity was additionally studied in Tetrahymena thermophila and HEK293 cells, and compared to that of resveratrol, showing that compounds 1 – 6 display lower toxicity than that of resveratrol, a well-known non-toxic polyphenol. [ABSTRACT FROM AUTHOR]