Significados atribuídos ao envelhecimento ativo e saudável em um grupo de pessoas vivendo em comunidade idosos

Indexación: Scopus.Objetivo: conocer e interpretar las experiencias y los significados que le atribuyen al envejecimiento activo y saludable un grupo de personas mayores de 64 años que viven en comunidad en la ciudad de Montevideo, Uruguay. Método: se optó por el método cualitativo con enfoque hermenéutico dialéctico. La recolección de datos se realizó a través de entrevistas en profundidad a 11 personas mayores de 64 años de la ciudad de Montevideo, Uruguay. Resultados: el análisis de los datos permitió construir las categorías de: desarrollo personal, alteración del estado físico, pérdidas, cambios del rol social, falta de reconocimiento, actividades de recreación. Conclusión: se identificaron aspectos relevantes sobre las necesidades de sentirse útiles para la sociedad y familia, reconocen que su capacidad funcional ha disminuido, sienten limitaciones físicas. Se devela el sentimiento de las pérdidas, tanto económicas, como físicas y laborales. Manifiestan que una fortaleza es su salud mental la que los mantiene vivos y activos.Objective: to find out and interpret the experiences and meanings attributed to the active and healthy aging of a group of elderly people over 64 living in community in the city of Montevideo, Uruguay. Method: we chose the qualitative method with dialectical hermeneutic approach. Data collection occurred through in-depth interviews with 11 elderly people aged 64 or more in the city of Montevideo, Uruguay. Results: data analysis allowed us to construct the categories personal development, physical state changing, losses, social role changes, lack of recognition, recreation activities. Conclusion: we identified relevant aspects on the need to feel useful for society and family; they recognize that their functional capacity has decreased; they feel physical limitations. Feelings of economic, physical and labor losses showed up in the study. They point out that their mental health is their strength that keeps them alive and active.http://ref.scielo.org/zq7wr

Electromodulation of the Magnetoresistance in Diluted Magnetic Semiconductors Based Heterostructures

We study the properties of heterostructures formed by two layers of diluted magnetic semiconductor separated by a nonmagnetic semiconductor layer. We find that there is a RKKY-type exchange coupling between the magnetic layers that oscilles between ferromagnetic and antiferromagnetic as a function of the different parameters in the problem. The different transport properties of these phases make that this heterostructure presents strong magnetoresistive effects. The coupling can be also modified by an electric field. We propose that it is possible to alter dramatically the electrical resistance of the heterostructure by applying an electric field. Our results indicate that in a single gated sample the magnetoresistance could be modulated by with an electrical bias voltage.Comment: 4 pages, 5 figures include

IL-17A and Streptococcus pneumoniae respiratory infection: Prospects for the development of new immunotherapies

Nasopharyngeal colonization by Streptococcus pneumoniae constitutes a pre-requisite for development of pneumonia and invasive pneumococcal diseases. Colonization is typically asymptomatic and is resolved due to a dynamic and complex interplay between microbiota, host immune system and environmental factors. Working with a murine model of pneumococcal nasopharyngeal colonization, we have shown that IL-17A is a key cytokine in this process, since Il17a-/- mice were persistently colonized for up to 6 months whereas wild type mice cleared colonization in 10 days. We are currently trying to elucidate the downstream mechanisms that may account for the phenotype showed in Il17a-/- mice, including the production of specific antibodies, as well as the recruitment of innate cells and the expression of immune mediators in WT and Il17a-/- mice. On the other hand, we have studied the role of IL-17A in the development of protective immunity against acute pneumococcal pneumonia. Previously, we showed that prior sublethal infection resulted in solid protection against invasive pneumonia which is associated with over expression of IL-17A together with the presence of Th17 cells in the lungs. However, Il17a-/- mice showed same level of protection than WT, demonstrating that IL-17A by itself is not essential for protective immunity. Interestingly Il17a-/- mice showed overexpression of other IL-17 related genes suggesting a complex network where compensatory effects may be occurring. Finally, we have developed and tested alternative immunotherapies against pneumococcal pneumonia, and have evaluated the role of IL17A in the protection afforded. Overall, we believe that deciphering the molecular basis of protective immunity will result in the development of new cost-effective immunotherapies against pneumococcal pneumonia

Superoxide dismutase in patients with chronic hepatitis C virus infection

It has been reported that hepatitis C virus (HCV) may cause oxidative stress in infected cells. Patients with chronic hepatitis C exhibit an increased production of tumor necrosis factor-alpha (TNF alpha), a cytokine that can produce oxidative stress by stimulating the generation of reactive oxygen species (ROS). Cell defense against ROS includes overexpression of Mn-superoxide dismutase (SOD), an inducible mitochondrial enzyme. To investigate cell defense against oxidative stress in HCV infection, we analyzed Mn-SOD mRNA in liver and in peripheral blood mononuclear cells (PBMC) from patients with chronic hepatitis C. Mn-SOD expression in PBMC was significantly increased in patients with HCV infection. Patients with sustained virological and biochemical response after therapy showed significantly lower Mn-SOD than patients with positive viremia. By contrast, Mn-SOD expression was not enhanced in the liver of patients with chronic hepatitis C. The values of Mn-SOD mRNA did not correlate with TNF alpha mRNA expression, viral load, or liver disease activity. Our results indicate that in HCV infection an induction of Mn-SOD was present in PBMC but absent in the liver, suggesting that this organ could be less protected against oxidative damage. Oxidative stress could participate in the pathogenesis of HCV infection

Interdigitated μ-electrodes for development of an impedimetric immunosensor for atrazine detection.

This contribution describes the development of an impedimetric immunosensor for atrazine detection. This immunosensor is based on the use of interdigitated metallic μ-electrodes (IDμEs) The method described in this work does not use any redox mediator and relies on the direct detection of immunochemical competitive reaction between the pesticide and a haptenized-protein immobilized on interdigitated μ-electrodes for the specific antibody. The immunoreagents used were specifically developed to detect atrazine. The immunochemical detection of this pesticide is achieved without using any label. The immunosensor shows a limit of detection of 8.34±1.37 μg L-1, witch is lower than the Maximun Residue Level (MRL) (50μg L-1)established by EU (European Union)for residues of atrazine as herbicide in the wine grapes and other foodstuff products.Peer ReviewedPostprint (published version

Deterministic and time resolved thermo-magnetic switching in a nickel nanowire

[EN]Heating a ferromagnetic material is often perceived as detrimental for most applications. This is indeed the case for modern nano-scaled spintronic devices which are operated solely (at least ideally) by an electric current. Heat is a by-product of the current-driven operation and it deteriorates many functionalities of the device. A large scientific and technological effort is devoted these days to avoid heat in modern magnetic nano devices. Here we show that heat can be used to provide an additional and useful degree of freedom in the control of the local magnetization at the nanoscale. In a ferromagnetic nanowire, temperature is used to induce a magnetic switching through a perfectly deterministic mechanism. The nucleation of the magnetic domain walls that triggers the switching can be achieved at a field considerably smaller than the nucleation field and, importantly, the exact moment of the magnetic switching can be pre-determined with nanosecond precision by controlling the power delivered locally to the switching area. With the help of micromagnetic simulations and a theoretical model, we provide an accurate explanation of how this deterministic thermo-magnetic switching operates. The concepts described in this work may lead to an increased functionality in magnetic nano-devices based on magnetic domain walls.MAT2017-87072-C4-1-P,MAT2017-87072-C4-4-P and MAT2017-87072-C4-3-P from the Spanish government SA299P18 from the Junta de Castilla y Leon POCI-01-0145-FEDER-028676 from Portuguese FCT COMPETE 2020 (FEDER)

Anticancer activity and DNA interaction of bis(pyridyl)allene-derived metal complexes

The constant need for novel drugs has prompted the scientific community to explore alternative structures to natural products and small and medium size organic compounds used in classic medicinal and pharmaceutical chemistry. Since the discovery of cisplatin, organometallic compounds have revealed great potential as metallodrugs and their development has exponentially grown in recent years. In this manuscript, we describe our efforts towards the synthesis of new metallodrugs by reaction of bis(pyridyl)allenes and metal complexes. Two classes of compounds are presented: one in which the allene structure is intact and the metal (Pd(II), Pt(IV) or Au(III)) coordinates to the pyridine-nitrogens; and another, in which one of the pyridines cyclises into a gold-activated allene to form β-N-stabilised gold carbenes. Both classes of compounds are active catalysts in important organic reactions, and are also promising antimicrobial, antifungal and anticancer agents. In this work, we describe the promising anticancer activity, against breast cancer cells, of the gold carbene complexes, and preliminary studies of their interaction with DNA, including non-canonical DNA structures. Our results have revealed an unusual selective stabilisation of hTeloC i-motif by one of the Au(III) carbene complexes, that opens up exciting opportunities for further development of novel DNA-binding metallodrugs

Metodología de investigación de Rocas Ornamentales: Granitos.

Durante la realización del proyecto del IGME ·Potencial Básico de Granitos y Neises Ornamentales en Castilla y León se desarrolló una metodología sistemática de investigación de granitos para uso ornamental que, por su versatilidad, puede hacerse extensible, en sus aspectos más generales, a otros tipos de rocas ornamentales e, incluso, rocas industriales en general. Para ello, se desarrollan una serle de fases de trabajo que comprenden: recogida de información, exploración de campo a escalas 1 :50.000, 1 :25.000 y 1: 10.000, valoración de áreas y elección de puntos canterables, todo ello mediante la cuantificación de todos los parámetros y valores que han de tenerse en cuenta en la investigación de rocas ornamentales, que nos permiten dar un tratamiento objetivo a todas las áreas estudiadas

Myelinating oligodendrocytes generated by direct cell reprogramming from adult rat adipose tissue

Obtaining oligodendroglial cells from dispensable tissues would be of great interest for autologous or immunocompatible cell replacement in demyelinating diseases as well as for studying myelin pathologies. Recently, two laboratories have simultaneously reported that mouse fibroblasts could be converted into oligodendroglial cells by direct reprogramming with transcription factors involved in oligodendrocyte development (Najm et al., Nat. Biotechnol. 31:426, 2013, Yang et al., Nat. Biotechnol. 31:434, 2013). We have lentivirally transfected combinations of tetracycline-inducible sox10 (S), olig2 (O), zfp536 (Z) and/or nkx6.1 (N) transgenes in adult rat adipose tissue-derived stromal cells (ADSCs) and checked for the generation of functional oligodendrocytes. Immunostaining with the O4 monoclonal, which binds to oligodendrocyte progenitor cell membranes, was used as initial marker of oligodendroglial reprogramming. The first signs of ADSC conversion into oligodendrocytic cells were observed with the S-O-Z combination by 6 weeks and the O4+ cell population kept rising the following months, eventually constituting more than 50% of cells. Increasing numbers of O1 (galactocerebroside), p75 (low-affinity NGF receptor), and GFAP-positive cells appeared in that period. Cells expressed also myelin-associated proteins like MBP, MAG, MOG and PLP1/DM20. Transduction with the S-O-N-Z transgene combination also produced oligodendrocyte progenitors but did not improve the result; S-O-N, O-Z or O transductions did not consistently produce oligodendrocytes in our hands. After 3 months of continuous expansion, the reprogrammed cells became independent of transgene activation by doxycycline. Antibiotic selection of transduced cells (with zeocin) did not show to be more efficient for reprogrammed cell purity and proliferation than unselected cultures. Different pre-induction treatments were tried in an attempt to improve the efficiency or speed of reprogramming: of these, treatment with Repsox followed by retinoic acid or adipocytic pre-differentiation, appeared to increase reprogramming consistency or to slightly accelerate the process. When seeded onto rat dorsal root ganglion neurons, transdifferentiated cells were observed to cover lengths of one or several axons with typical myelin-like appearance. We propose that functional oligodendrocytes can be efficiently generated from adult mesenchymal cells in the rat by direct cell reprogramming

Magnetic Nanoparticles for Power Absorption: optimizing size, shape and magnetic properties

We present a study on the magnetic properties of naked and silica-coated Fe3O4 nanoparticles with sizes between 5 and 110 nm. Their efficiency as heating agents was assessed through specific power absorption (SPA) measurements as a function of particle size and shape. The results show a strong dependence of the SPA with the particle size, with a maximum around 30 nm, as expected for a Neel relaxation mechanism in single-domain particles. The SiO2 shell thickness was found to play an important role in the SPA mechanism by hindering the heat outflow, thus decreasing the heating efficiency. It is concluded that a compromise between good heating efficiency and surface functionality for biomedical purposes can be attained by making the SiO2 functional coating as thin as possible.Comment: 15 pages, 7 figures, 2 table