Exploring the Factor Structure of Neurocognitive Measures in Older Individuals

Here we focus on factor analysis from a best practices point of view, by investigating the factor structure of neuropsychological tests and using the results obtained to illustrate on choosing a reasonable solution. The sample (n=1051 individuals) was randomly divided into two groups: one for exploratory factor analysis (EFA) and principal component analysis (PCA), to investigate the number of factors underlying the neurocognitive variables; the second to test the “best fit” model via confirmatory factor analysis (CFA). For the exploratory step, three extraction (maximum likelihood, principal axis factoring and principal components) and two rotation (orthogonal and oblique) methods were used. The analysis methodology allowed exploring how different cognitive/psychological tests correlated/discriminated between dimensions, indicating that to capture latent structures in similar sample sizes and measures, with approximately normal data distribution, reflective models with oblimin rotation might prove the most adequate.     

Cross-Reactivity of Neutralizing Antibodies among Malignant Catarrhal Fever Viruses

Some members of the gamma herpesvirus genus Macavirus are maintained in nature as subclinical infections in well-adapted ungulate hosts. Transmission of these viruses to poorly adapted hosts, such as American bison and cattle, can result in the frequently fatal disease malignant catarrhal fever (MCF). Based on phylogenetic analysis, the MCF viruses (MCFV) cluster into two subgroups corresponding to the reservoir hosts’ subfamilies: Alcelaphinae/Hippotraginae and Caprinae. Antibody cross-reactivity among MCFVs has been demonstrated using techniques such as enzyme linked immunosorbent and immunofluorescence assays. However, minimal information is available as to whether virus neutralizing antibodies generated against one MCFV cross react with other members of the genus. This study tested the neutralizing activity of serum and plasma from select MCFV-infected reservoir hosts against alcelaphine herpesvirus 1 (AlHV-1) and ovine herpesvirus 2 (OvHV-2). Neutralizing antibody activity against AlHV-1 was detected in samples from infected hosts in the Alcelaphinae and Hippotraginae subfamilies, but not from hosts in the Caprinae subfamily. OvHV-2 neutralizing activity was demonstrated in samples from goats (Caprinae) but not from wildebeest (Alcelaphinae). These results show that neutralizing antibody cross reactivity is present to MCFVs within a virus subgroup but not between subgroups. This information is important for diagnosing infection with MCFVs and in the development of vaccines against MCF.     

Morphological and histological study of castration-induced degeneration and androgen-induced regeneration in the mouse prostate

Degenerative and regenerative changes in the ductal architecture of the ventral and dorsolateral prostates (VP and DLP) of the adult mouse were investigated in microdissected specimens over a time-course of 14 days following castration and subsequently during 14 days of administration of testosterone propionate. After castration, about 35% of the ductal tips and branch-points were lost in distal regions (usually near the capsule) in both prostatic lobes. By contrast, in more proximal regions of the prostate (closer to the urethra), the ducts survived in an atrophic condition. The ductal morphology that had been lost in the distal regions completely regenerated after testosterone propionate was administered to the castrated males. In the VP, androgen replacement simply returned the gland to its former size with moderate ductal distension; in the DLP, excessive epithelial infoldings and ductal distension were elicited in the distal regions of the ducts after 14 days of treatment with testosterone propionate. These results suggest that androgenic responsiveness and dependency are different in distal versus proximal ducts. Distal ducts are exquisitely androgen-dependent and androgen-sensitive; in proximal regions, androgen-dependency is not as strict.     

The Trophic Effect of Ouabain on Retinal Ganglion Cell is Mediated by EGF Receptor and PKC δ Activation

It was already shown that ouabain treatment can stimulate PKC isoenzymes leading to the activation of intracellular pathways involved in cell survival, growth and proliferation. We have previously demonstrated that ouabain or PMA treatment increases retinal ganglion cell survival, an effect mediated by PKC activation. The aim of this work was to investigate the role of EGF receptors in the ouabain effect and also to study which PKC isoform is activated by treatment with ouabain and PMA. Our results show that 2.5 μM tyrphostin, 1.0 μM PP1, 4.0 μM U73122, 1.0 μM JNK inhibitor V and 2.0 μM rottlerin blocked the ouabain effect indicating an involvement of receptors for EGF, Src, PLC, JNK and PKC δ respectively. The effect of PMA was only abolished when cultures were treated with rottlerin or with the JNK inhibitor suggesting the involvement of PKC δ and JNK. These results indicate that PKC δ could be a key regulator of retinal ganglion cell survival.     

Structural and ecophysiological adaptations to forest gaps

To survive new microclimatic conditions of a forest gap environment, plant species must physiologically and structurally adjust. A morpho-anatomical, ultrastructural and ecophysiological study was performed at three different times in a forest gap that was created by illegal selective logging. The study followed the early successional Actinostemon verticillatus and the late-successional Metrodorea brevifolia, to elucidate the adaptive strategies of acclimation to gaps. Additionally, Schinus terebinthifolius was included in the study in order to test the plasticity of a pioneer species that grows on forest edges, where this species had higher values of leaf thickness, leaf mass area and succulence. M. brevifolia had succulent leaves, high leaf area and a thin cuticle. A. verticillatus presented the densest leaves and was the only species to show leaf morpho-anatomical plasticity. Ultrastructural and physiological differences were observed only in A. verticillatus and M. brevifolia leaves from the gap: increase in the stroma volume, oil droplets, plastoglobuli, photochemical and non-photochemical quenching. Photosynthetic efficiency showed that the early stages of gap formation are the most critical. Acclimation strategies of A. verticillatus suggest this species invests in the efficiency of photosynthesis by increasing its leaf thickness, leaf mass area and in water content maintenance by increasing the density of its leaves, at the expense of gas exchange, was compensated by a high density of stomata. M. brevifolia compensates for the higher cost of leaves and lower leaf plasticity with ultrastructural changes that are used to adjust the photosynthetic process, which promotes a shorter leaf payback time.     

From the saltpan to the plate: An evaluation of the use of the edible halophyte Salicornia ramosissima in catering

The halophyte species Salicornia ramosissima has long been consumed as food and is currently regarded as a high-value gourmet item. However, given that these plants grow in estuarine areas, often impacted by pollution, and are prone to the accumulation of ions, the risks associated with food borne pathogens or toxic metals has to be carefully considered. The objective of this work was to gather evidence that S. ramossissima harvested locally in an estuarine system (Ria de Aveiro, Portugal) can be safely consumed as a healthy and catering-amenable food. Fresh shoots, taken as green vegetables, and dried powdered shoots (green salt) intended as seasoning, were analysed for total aerobic bacteria, total coliforms, Escherichia coli, Bacillus cereus and fungi (yeasts and moulds). The nutritional profile and the concentration of macro and micro elements, including potential toxic elements, was also established. Fresh shoots and green salt were incorporated in catering meals (soup and a meat dish) and subjected to sensory analyses. The microbiological quality of fresh shoots and green salt was compliant with the guidelines for salad greens and herbs and spices, respectively. The nutritional and elemental profile revealed that fresh shoots have a high content in fibre and NaCl. From the concentration of Na determined in green salt, a daily dose of 7 g was estimated as corresponding to the recommended daily dietary intake Na. None of the other elements was present in concentrations that could exceed the dietary intake limits. In the sensory tests, fresh shoots were well accepted as salad greens but green salt, used as seasoning, was considered as insufficient in terms of saltiness and does not completely substitute cooking salt. The results confirm the nutritional and sensory value of S. ramossisima and represent a promising prospect for the incorporation of locally harvested or crop cultivated plants in catering meals.