La evaluación de la calidad de vida en personas con demencia

Quality of life (QoL) is one of the most important outcome variables in the study of the efficacy of interventions with people with dementia. However, its assessment is difficult 1) because it is a complex construct for which there is no unified theoretical or conceptual approach, and 2) because of the inherent difficulties in the cognitive impairments of the people under study. In this work different methods and instruments to this end are reviewed, and related findings are discussed. It is important to take into account the subjective view of the assessed person, as assessments done by proxies tend to underestimate QoL. In spite of the need for further development in this field, it is concluded that the instrument of choice is the QOL-AD, as it is change-sensitive, it correlates with health measurements, it is translated into several languages and it can be administered to people with low MMSE scores.     

Modulation of prion protein oligomerization, aggregation, and beta-sheet conversion by 4,4'-dianilino-1,1'-binaphthyl-5,5'-sulfonate (bis-ANS)

The prion protein (PrP) is the major agent implicated in the diseases known as transmissible spongiform encephalopathies. The onset of transmissible spongiform encephalopathy is related to a change in conformation of the PrP(C), which loses most of its alpha-helical content, becoming a beta-sheet-rich protein, known as PrP(Sc). Here we have used two Syrian hamster prion domains (PrP 109-141 and PrP 109-149) and the murine recombinant PrP (rPrP 23-231) to investigate the effects of anilino-naphtalene compounds on prion oligomerization and aggregation. Aggregation in the presence of bis-ANS (4,4'-dianilino-1,1'-binaphthyl-5,5'-sulfonate), ANS (1-anilinonaphthalene-8-sulfonate), and AmNS (1-amino-5-naphtalenesulfonate) was monitored. Bis-ANS was the most effective inhibitor of prion peptide aggregation. Bis-ANS binds strongly to rPrP 23-231 leading to a substantial increase in beta-sheet content and to limited oligomerization. More strikingly, the binding of bis-ANS to full-length rPrP is diminished by the addition of nanomolar concentrations of oligonucleotides, demonstrating that they compete for the same binding site. Thus, bis-ANS displays properties similar to those of nucleic acids, causing oligomerization and conversion to beta-sheet (Cordeiro, Y., Machado, F., Juliano, L., Juliano, M. A., Brentani, R. R., Foguel, D., and Silva, J. L. (2001) J. Biol. Chem. 276, 49400-49409). This dual effect of bis-ANS on prion protein makes this compound highly important to sequester crucial conformations of the protein, which may be useful to the understanding of the disease and to serve as a lead for the development of new therapeutic strategies.     

An integrative taxonomic revision of the Cape Verdean skinks (Squamata,Scincidae)

Miralles, A., Vasconcelos, R., Perera, A., Harris, D. J. & Carranza, S. (2010). An integrative taxonomic revision of the Cape Verdean skinks (Squamata, Scincidae). —Zoologica Scripta, 40, 16–44. A comprehensive taxonomic revision of the Cape Verdean skinks is proposed based on an integrative approach combining (i) a phylogenetic study pooling all the previously published molecular data, (ii) new population genetic analyses using mitochondrial and nuclear data resulting from additional sampling, together with (iii) a morphological study based on an extensive examination of the scalation and colour patterns of 516 live and museum specimens, including most of the types. All Cape Verdean species of skinks presently recognised, formerly regarded as members of the genera Mabuya Fitzinger, 1826 and Macroscincus Bocage, 1873 are considered as members of the Cape Verdean endemic genus Chioninia Gray, 1845. The new phylogeny and networks obtained are congruent with the previously published phylogenetic studies, although suggesting older colonization events (between 11.6 and 0.8 Myr old), and indicate the need for taxonomic changes. Intraspecific diversity has been analysed and points to a very recent expansion of Chioninia delalandii on the southern islands and its introduction on Maio, to a close connection between Chioninia stangeri island populations due to Pleistocene sea‐level falls and to a generally low haplotypic diversity due to the ecological and geological characteristics of the archipelago. Three new consistent morphological synapomorphies supporting two of the four main clades of the genus have been identified. The complex taxonomic status of Euprepes fogoensis O’Shaughnessy, 1874 has been resolved and a lectotype has been designated for this species; Chioninia fogoensis nicolauensis (Schleich, 1987) is elevated to species rank, whereas Chioninia fogoensis antaoensis (Schleich, 1987) is now regarded as a junior subjective synonym of C. fogoensis. Additionally, one new subspecies of Chioninia vaillanti and two of Chioninia spinalis are described (Chioninia vaillanti xanthotis ssp. n., Chioninia spinalis santiagoensis ssp. n. and Chioninia spinalis boavistensis ssp. n.) and a lectotype has been designated for Mabuia spinalis Boulenger, 1906. Finally, an identification key for the Chioninia species is presented.     

Prevalence of potentially pathogenic culturable bacteria on eggshells and in cloacae of female Pied Flycatchers in a temperate habitat in central Spain

ABSTRACT Bacteria grow on avian eggshells and thus can potentially cause diseases in developing embryos. Little is known about culturable bacteria colonizing avian eggshells in free‐living birds, with most studies restricted to poultry. Our objective was to examine the culturable bacterial array growing on eggshells during incubation that could negatively affect hatching success of Pied Flycatchers (Ficedula hypoleuca) in a temperate montane habitat in central Spain. Cloacal culturable bacteria of females were also analyzed because bacteria can be vertically transmitted from females to eggs. We used fecal samples as surrogates of cloacal samples due to the small size of sampled birds. We found that eggshells and female cloacae of Pied Flycatchers harbored 24 and 40 bacterial families and species, respectively, but only a few in each clutch and each cloaca. Rod‐shaped gram‐negative bacteria and bacteria in the family Pseudomonadaceae were the most common bacteria on eggshells during early and late incubation and in female cloacae. Although based on small sample sizes, we found that females with rod‐shaped gram‐negative bacteria in their cloacae laid eggs that also had these bacteria, providing possible evidence for vertical transmission. We found no evidence for vertical transmission of Pseudomonadaceae, suggesting a possible environmental source for these bacteria. The prevalence of bacterial morphological types and major taxonomical categories on eggshells did not vary from early to late stages of incubation, providing support for the hypothesis that incubation may have bacteriostatic effects on bacterial proliferation on eggshells. Despite being primary egg invaders in poultry, we detected no effects of culturable Pseudomonadaceae or Pseudomonas luteola on hatching success. Our study represents the first to examine the culturable bacteria growing on the eggshells of a wild bird in a temperate habitat and additional studies based on culture‐independent techniques are required to confirm our results.     

Cluster root formation and function vary in two species with contrasting geographic ranges

Plant and Soil - Southern South American Proteaceae can occupy soils that are rich in total phosphorus (P) but poor in available P (for example volcanic soils) thanks to their cluster roots (CR),...     

Increased performance of Cirsium arvense from the invasive range

The Evolution of Increased Competitive Ability (EICA) hypothesis suggests that plants from the invasive range should perform better than plants of the same species from the native range. To properly test this, we need to compare growth of plants from the two ranges in a common environment. Ideally, all the natural enemies should be excluded, to make sure that the differences are not due to different response of plants from the two ranges to the natural enemies. We used the above design to examine the difference in growth and reproduction in Cirsium arvense plants from the invasive (North America) and native range (Europe). To account for possible differences within the ranges, we used plants from two regions, separated by at least 1000 km, in each range. Because the higher performance of species from the invasive range can be caused by their higher ability to acquire resources we compared growth of the plants in two different nutrient levels. The results indicate that plants from the invasive range are larger in most size parameters as well as parameters more closely related to fitness. For aboveground biomass, the response of plants from the invasive range to nutrient addition was weaker than that of plants from the native range and the difference between the ranges was stronger in the nutrient poor substrate. The results are in agreement with the EICA hypothesis and suggest that plants from the invasive range have higher ability to use resources and are thus able to perform well also in nutrient poor conditions.     

The formation of titan cells in Cryptococcus neoformans depends on the mouse strain and correlates with induction of Th2‐type responses

Cryptococcus neoformans is a pathogenic yeast that can form titan cells in the lungs, which are fungal cells of abnormal enlarged size. Little is known about the factors that trigger titan cells. In particular, it is not known how the host environment influences this transition. In this work, we describe the formation of titan cells in two mouse strains, CD1 and C57BL/6J. We found that the proportion of C. neoformans titan cells was significantly higher in C57BL/6J mice than in CD1. This higher proportion of titan cells was associated with a higher dissemination of the yeasts to the brain. Histology sections demonstrated eosinophilia in infected animals, although it was significantly lower in the CD1 mice which presented infiltration of lymphocytes. Both mouse strains presented infiltration of granulocytes, but the amount of eosinophils was higher in C57BL/6J. CD1 mice showed a significant accumulation of IFN‐γ, TNF‐α and IL17, while C57BL/BL mice had an increase in the anti‐inflammatory cytokine IL‐4. IgM antibodies to the polysaccharide capsule and total IgE were more abundant in the sera from C57BL/6J, confirming that these animals present a Th2‐type response. We conclude that titan cell formation in C. neoformans depends, not only on microbe factors, but also on the host environment.