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Background: Dementia of the Alzheimer's type (DAT) impacts Hispanics disproportionately, with almost a twofold elevated risk of developing DAT, as well as earlier onset of the disease, than in non-Hispanic Whites. However, the role of main risk factors for DAT, such as APOE-ϵ4 and blood pressure (BP) levels, remains uncertain among Hispanics. Objective: To investigate the association of APOE-ϵ4 and BP levels, measures with 24-h ambulatory BP monitoring, with incidence of DAT in an elderly cohort of Hispanics. Methods: 1,320 participants from the Maracaibo Aging Study, free of dementia at the baseline, and with ambulatory BP measurements and APOE genotype available were included. Adjusted Cox proportional models were performed to examine 1) the incidence of DAT and 2) the relationship between BP levels and DAT according to APOE genotypes. Models were adjusted by competing risk of death before the onset of DAT. Model performance was assessed by likelihood test. Results: The average follow-up time was 5.3 years. DAT incidence was 5.8 per 1000 person-year. APOE-ϵ4 carriers had a higher risk of DAT. In unadjusted analyses, conventional, 24-h, and nighttime systolic BP levels were significantly higher in participants who developed DAT and of APOE-ϵ4 carriers (p < 0.05). After adjustment for competing risks, only higher nighttime systolic BP was associated with DAT incidence, but only among subjects carrying APOE-ϵ4. Conclusion: In this Hispanic population, both APOE-ϵ4 genotype and assessment of nocturnal systolic BP (rather than diurnal or office BP) were necessary to estimate DAT risk. © 2020 - IOS Press and the authors. All rights reserved.

Allelopathy, the release of phytotoxins by plants, may be a key mechanism by which an invasive species displaces residents. However, methodological procedures are still questioned in the literature. We evaluated the phytotoxic effects of Cynodon dactylon and Eragrostis plana, the most invasive grasses of the Río de la Plata grasslands. Although allelopathy has been claimed as one of the possible mechanisms involved in the establishment and impact of these species, no empirical evidence has convincingly supported it. We performed a germination experiment to assess the effect of both invasive species on Eragrostis bahiensis, a native grass from the region. We used aqueous extracts from fresh and dry leaves of three donor species: two invasive (C. dactylon and E. plana) and one co-occurring native from the introduced range (Coelorachis selloana). This approach allows to relativize the invasive species effect from resident species, according to the novel weapon hypothesis. As a result, only aqueous extracts from dried leaves inhibited the germination and early growth of E. bahiensis. The magnitude of these effects varied between donor species, but there was no consensus to conclude both invasive species had greater effects. Cynodon dactylon caused the strongest inhibitory effect on E. bahiensis. However, the native C. selloana also presented a potent inhibitory effect, stronger than the well-known invasive E. plana. Thus, the role of allelopathy on E. plana invasion in the Río de la Plata grasslands should be questioned. Finally, we addressed some suggestions for improving experimental design for testing the novelty of phytotoxic effects in the introduced range.

The presence of alkali cations in zeolite framework provides peculiar basic properties that influence the characteristics and reactivity of supported metal particles. Particularly, the addition of increasing amounts of cesium in Pt/Na-BEA and Pt/Cs-BEA catalysts, by CsOH impregnation, leads to changes of the oxidation state and reducibility of Pt species present in the zeolite microporosity. For similar contents of impregnated Cs, the metal dispersion is higher in Pt/Cs-BEA than in Pt/Na-BEA series, showing that both the amount of Cs excess and the nature of the compensating cation affect the characteristics of the Pt species. In the case of Cs-overloaded Pt/Cs-BEA, the size of Pt nanoclusters is below 10 A . TheverysmallPtnanoparticlesinreducedCs-overloadedPt/Cs-BEAareparticularlyactiveinaromatizationofn-hexane

Salles, F.F., Andrade, M.B., Da-Silva, E.R. (2005): Camelobaetidius francischettii: a new species of Baetidae (Ephemeroptera) from Brazil. Zootaxa 1027 (1): 47-53, DOI: 10.11646/zootaxa.1027.1.3, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.1027.1.3