Stone tool use by adult wild bearded capuchin monkeys (Cebus libidinosus). Frequency, efficiency and tool selectivity

Chimpanzees have been the traditional referential models for investigating human evolution and stone tool use by hominins. We enlarge this comparative scenario by describing normative use of hammer stones and anvils in two wild groups of bearded capuchin monkeys (Cebus libidinosus) over one year. We found that most of the individuals habitually use stones and anvils to crack nuts and other encased food items. Further, we found that in adults (1) males use stone tools more frequently than females, (2) males crack high resistance nuts more frequently than females, (3) efficiency at opening a food by percussive tool use varies according to the resistance of the encased food, (4) heavier individuals are more efficient at cracking high resistant nuts than smaller individuals, and (5) to crack open encased foods, both sexes select hammer stones on the basis of material and weight. These findings confirm and extend previous experimental evidence concerning tool selectivity in wild capuchin monkeys ( [Visalberghi et?al., 2009b] and [Fragaszy et?al., 2010b]).Male capuchins use tools more frequently than females and body mass is the best predictor of efficiency, but the sexes do not differ in terms of efficiency. We argue that the contrasting pattern of sex differences in capuchins compared with chimpanzees, in which females use tools more frequently and more skillfully than males, may have arisen from the degree of sexual dimorphism in body size of the two species, which is larger in capuchins than in chimpanzees. Our findings show the importance of taking sex and body mass into account as separate variables to assess their role in tool use.     

Dementia and legal competency

The legal competency or capability to exercise rights is level of judgment and decision-making ability needed to manage one's own affairs and to sign official documents. With some exceptions, the person entitles this right in age of majority. It is acquired without legal procedures, however the annulment of legal capacity requires a juristic process. This resolution may not be final and could be revoked thorough the procedure of reverting legal capacity - fully or partially. Given the increasing number of persons with dementia, they are often subjects of legal expertise concerning their legal capacity. On the other part, emphasis on the civil rights of mentally ill also demands their maximal protection. Therefore such distinctive issue is approached with particular attention. The approach in determination of legal competency is more focused on gradation of it's particular aspects instead of existing dual concept: legally capable - legally incapable. The main assumption represents how person with dementia is legally capable and should enjoy all the rights, privileges and obligations as other citizens do. The aspects of legal competency for which person with dementia is going to be deprived, due to protection of one's rights and interests, are determined in legal procedure and then passed over to the guardian decided by court. Partial annulment of legal competency is measure applied when there is even one existing aspect of preserved legal capability (pension disposition, salary or pension disposition, ability of concluding contract, making testament, concluding marriage, divorce, choosing whereabouts, independent living, right to vote, right to decide course of treatment ect.). This measure is most often in favour of the patient and rarely for protection of other persons and their interests. Physicians are expected to precisely describe early dementia symptoms which may influence assessment of specific aspects involved in legal capacity (memory loss, impaired task execution, language difficulties, loosing perception of time and space, changes in mood and behaviour, personality alterations, loss of interests and initiative). Towards more accurate determination of legal competency the psychometric tests are being used. The appliance of these tests must be guided with basic question during evaluation: "For what is or is not he/she capable?" In prediction of possible dementia development, the modern diagnostic procedures are used as help for potentially demented individuals in order to plan own affairs and by oneself determine future guardian. This ensures the maximal respect and protection of rights among persons with dementia in order to independently manage life one step ahead of progressive illness. Finally, it is to be distinguished medical concept of legal capacity which is universal and judicial concept which is restricted by rules of national legal system differing from country to country.     

Root cultures of <Emphasis Type="Italic">Hypericum perforatum</Emphasis> subsp. <Emphasis Type="Italic">angustifolium</Emphasis> elicited with chitosan and production of xanthone-rich extracts with antifungal activity

Hypericum perforatum is a well-known medicinal plant which contains a wide variety of metabolites, including xanthones, which have a wide range of biological properties, including antifungal activity. In the present study, we evaluated the capability of roots regenerated from calli of H. perforatum subsp. angustifolium to produce xanthones. Root biomass was positively correlated with the indole-3-butyric acid concentration, whereas a concentration of 1 mg l⁻¹ was the most suitable for the development of roots. High auxin concentrations also inhibited xanthone accumulation. Xanthones were produced in large amounts, with a very stable trend throughout the culture period. When the roots were treated with chitosan, the xanthone content dramatically increased, peaking after 7 days. Chitosan also induced a release of these metabolites into the culture. The maximum accumulation (14.26 ± 0.62 mg g⁻¹ dry weight [DW]) and release (2.64 ± 0.13 mg g⁻¹ DW) of xanthones were recorded 7 days after treatment. The most represented xanthones were isolated, purified, and spectroscopically characterized. Antifungal activity of the total root extracts was tested against a broad panel of human fungal pathogen strains (30 Candida species, 12 Cryptococcus neoformans, and 16 dermatophytes); this activity significantly increased when using chitosan. Extracts obtained after 7 days of chitosan treatment showed high antifungal activity (mean minimum inhibitory concentration of 83.4, 39.1, and 114 μg ml⁻¹ against Candida spp., C. neoformans, and dermatophytes, respectively). Our results suggest that root cultures can be considered as a potential tool for large-scale production of extracts with stable quantities of xanthones.     

Transmigration of Neural Stem Cells across the Blood Brain Barrier Induced by Glioma Cells

Transit of human neural stem cells, ReNcell CX, through the blood brain barrier (BBB) was evaluated in an in vitro model of BBB and in nude mice. The BBB model was based on rat brain microvascular endothelial cells (RBMECs) cultured on Millicell inserts bathed from the basolateral side with conditioned media (CM) from astrocytes or glioma C6 cells. Glioma C6 CM induced a significant transendothelial migration of ReNcells CX in comparison to astrocyte CM. The presence in glioma C6 CM of high amounts of HGF, VEGF, zonulin and PGE₂, together with the low abundance of EGF, promoted ReNcells CX transmigration. In contrast cytokines IFN-α, TNF-α, IL-12p70, IL-1β, IL-6, IL-8 and IL-10, as well as metalloproteinases -2 and -9 were present in equal amounts in glioma C6 and astrocyte CMs. ReNcells expressed the tight junction proteins occludin and claudins 1, 3 and 4, and the cell adhesion molecule CRTAM, while RBMECs expressed occludin, claudins 1 and 5 and CRTAM. Competing CRTAM mediated adhesion with soluble CRTAM, inhibited ReNcells CX transmigration, and at the sites of transmigration, the expression of occludin and claudin-5 diminished in RBMECs. In nude mice we found that ReNcells CX injected into systemic circulation passed the BBB and reached intracranial gliomas, which overexpressed HGF, VEGF and zonulin/prehaptoglobin 2.     

Phosphate adsorption on bottom sediments of the Rio de la Plata

A study of the phosphate adsorption onto the bottom sediments of the Rio de la Plata has been made with the aim to understand the dynamics of this compound in the fluvio-marine system. Previous to the chemical analysis of the phosphate content, an extraction of the different adsorbed phosphate fractions have been made. In addition to phosphate, calcium, iron and aluminium in the sediment samples were determined. The phosphate is associated to the fine fractions of the sediments and good correlations with Al and Fe content in the bottom sediments were found. There is a relative decrease of the adsorbed phosphate on the bottom sediment in the areas where the influence of the marine water is more conspicuous; it is explained by the pH increase of the estuary waters due to the mixture with the marine waters. A hypothesis about the role of the ionic strength and the pH on the phosphate adsorption process is suggested.     

Cell therapy with autologous mesenchymal stromal cells in post-traumatic syringomyelia

Background aims

Recently, clinical studies show that cell therapy with mesenchymal stromal cells (MSCs) improves the sequelae chronically established in paraplegic patients, being necessary to know which of them can obtain better benefit.

Rab and Arf proteins at the crossroad between membrane transport and cytoskeleton dynamics

The intracellular movement and positioning of organelles and vesicles is mediated by the cytoskeleton and molecular motors. Small GTPases like Rab and Arf proteins are main regulators of intracellular transport by connecting membranes to cytoskeleton motors or adaptors. However, it is becoming clear that interactions between these small GTPases and the cytoskeleton are important not only for the regulation of membrane transport. In this review, we will cover our current understanding of the mechanisms underlying the connection between Rab and Arf GTPases and the cytoskeleton, with special emphasis on the double role of these interactions, not only in membrane trafficking but also in membrane and cytoskeleton remodeling. Furthermore, we will highlight the most recent findings about the fine control mechanisms of crosstalk between different members of Rab, Arf, and Rho families of small GTPases in the regulation of cytoskeleton organization.     

Production of fumonisins by endophytic strains of <Emphasis Type="Italic">Tolypocladium cylindrosporum</Emphasis> and its relation to fungal virus infection

Fumonisins were first discovered in Fusarium verticillioides, a fungus associated to disease and asymptomatic infections in maize. Afterwards, other fungal taxa have been found to produce fumonisins. The entomopathogenic ascomycete Tolypocladium cylindrosporum has been isolated from soil and also as an endophyte from leaves of grasses. The objectives of this work were to determine the in vitro production of fumonisin B (FB) mycotoxins and the immunosuppressive compound cyclosporine A (CyA) in several strains of T. cylindrosporum, and to examine the effect of fungal virus infection and temperature in FB production. FB₁ was detected in 30% of the strains, ranging from 0.16 to 5.52 μg cm^?2 in solid media, and FB₂ was detected in 78% of the strains, ranging from 0.764 to 40.92 μg cm^?2. CyA was not detected in any strain. The mean FB₂ concentration of the endophytic strain Tc37W was three times greater (p?<?0.05) than that of any other strain. Up to 34% more of FB₂ was detected in strains infected by the virus TcV3 than in the corresponding virus-free versions. The effect of temperature on FB₂ content was interactively significantly dependent on fungal strain and growth medium; in the YES medium, the FB₂ of virus-infected strains Tc37-1V and Tc37W increased by 67 and 16%, respectively, at 26 °C as compared to 20 °C. The FB concentration in some fungal strains was similar to that in fungi associated to food and feed intoxications.     

Two-Photon Bidirectional Control and Imaging of Neuronal Excitability with High Spatial Resolution In Vivo

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Description and Phylogeny of Urostyla grandis wiackowskii subsp. nov. (Ciliophora,Hypotricha) from an Estuarine Mangrove in Brazil

Interphase specimens, aspects of physiological reorganization and divisional morphogenesis were investigated in a strain of a hypotrichous ciliate highly similar to Urostyla grandis Ehrenberg, 1830 (type species of Urostyla), collected from a mangrove area in the estuary of the Paraíba do Sul river (Rio de Janeiro, Brazil). The results revealed that albeit interphase specimens match with the known morphologic variability in U. grandis, morphogenetic processes have conspicuous differences. Parental adoral zone is entirely renewed during morphogenesis, and marginal cirri exhibit a unique combination of developmental modes, in which left marginal rows originate from multiple anlagen arising from innermost left marginal cirral row, whereas right marginal ciliature originates from individual within‐row anlagen. Based on such characteristics, a new subspecies, namely U. grandis wiackowskii subsp. nov. is proposed, and consequently, U. grandis grandis Ehrenberg, 1830 stat. nov. is established. Bayesian and maximum‐likelihood analyses of the 18S rDNA unambiguously placed U. grandis wiackowskii as adelphotaxon of a cluster formed by other U. grandis sequences. The implications of such findings to the systematics of Urostyla are discussed.