39 research outputs found

    Intermediate monocytes and cytokine production associated with severe forms of chagas disease

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    Q1Monocytes are classified according to their CD14 and CD16 expression into classical (reparative), intermediate (inflammatory), and non-classical. This study assessed the frequency of monocyte and the relationship between monocyte subset percentages and the levels of blood cytokines in Colombian chagasic patients with different clinical forms. This study included chagasic patients in different clinical stages: indeterminate (IND) n = 14, chronic chagasic cardiomyopathy (CCC) n = 14, and heart transplant chagasic (HTCC) n = 9; controls with non-chagasic cardiopathy (NCC) n = 15, and healthy individuals (HI) n = 15. Peripheral blood mononuclear cells (PBMCs) were isolated, labeled for CD14, CD16, and HLA-DR, and analyzed by flow cytometry. Cytokines were measured with a bead-based immunoassay. Percentages of total CD14+ CD16+ and CD14+ HLA-DR+ monocytes were higher in patients with heart involvement (CCC, HTCC, and NCC) than controls. Percentages of intermediate monocytes increased in symptomatic chagasic patients (CCC and HTCC) compared to asymptomatic chagasic patients (IND) and controls (HI). Asymptomatic chagasic patients (IND) had higher percentages of classical monocytes, an increased production of CCL17 chemokine compared to chagasic symptomatic patients (CCC), and their levels of CCL17 was positively correlated with the percentage of classical monocyte subset. In CCC, the percentages of intermediate and classical monocytes were positively correlated with IL-6 levels, which were higher in this group compared to HI, and negatively with IL-12p40 concentration, respectively. Remarkably, there also was an important increased of classical monocytes frequency in three chronic chagasic patients who underwent cardiac transplant, of which one received anti-parasitic treatment. Our findings suggest that cardiac chagasic patients have an increased percentage of inflammatory monocytes and produce more IL-6, a biomarker of heart failure and left ventricular dysfunction, whereas asymptomatic chagasic individuals present a higher percentage of reparative monocytes and CCL17.N/

    Differentiation and multipotential characteristics of mesenchymal stem cells derived from adipose tissue of an endangered wild cat (Leopardus guigna)

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    Adipose tissue derived mesenchymal stem cells (AMSCs) had been isolated and used for cell therapy in domestic cats. For wild cats, the isolation of AMSCs has only been reported in the black-footed cat (Felis nigripes). AMSCs obtained from wild cats may be useful to treat injuries of endangered cat species that remain in captivity or arrive at wildlife rehabilitation centers. Additionally, AMSCs might allow improvement of cloning techniques or assist in derivation of induced pluripotent stem cells. Endangered wild cats such as the guigna (Leopardus guigna), an endemic and endangered species from Chile and Argentina, might benefit greatly from the development of novel treatments or techniques that can be applied for its conservation. The objective of this study was to characterise putative AMSCs from guigna in terms of their main biological attributes, particularly, growth kinetics, differentiation ability and surface marker expression. Results obtained from this characterisation were compared with AMSCs isolated from domestic cats. AMSCs were isolated from peritoneal adipose tissue of female cats and subcutaneous tissue from a female guigna. Migration potential, colony-forming unit assay, mesodermal differentiation and surface marker expression (CD45, CD44, CD90, MHCI and MHCII) were evaluated. Domestic cat and guigna AMSCs displayed similar growth properties in culture. Both AMSC types showed mesodermal differentiation potential, in vitro homing potential and similar surface marker expression. These results indicate that AMSCs from subcutaneous tissue of guigna could have potential use as regenerative treatment for this species and might be considered for use in other biotechnological applications

    Anodic oxidation of titanium for implants and prothesis: processing characterization and potential improvement of osteointegration

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    Among all biomaterials used for bone replacement, it is recognized that both commercially pure titanium (Ti c.p.) and Ti6Al4V alloy are the materials that show the best in vivo performance due to their excellent balance between mechanical, physical-chemical and biofunctional properties. However, one of its main drawbacks, which compromise the service reliability of the implants and its osteointegration capacity, is the thin film of fibrous tissue around the implant due to the bioinert behaviour of titanium. One of the alternatives more studied to improve the titanium osteointegration is the surface modification through the control of the roughness parameters within a specific range which is recognized that improve the osteoblasts adhesion. In this work is investigated the influence of different electrochemical processing conditions for surface modification of c.p. Ti, in their microstructural, morphological, topographical and mechanical properties, as well as in their biological behaviour. The electrochemical anodizing treatment was performed by using different electrolytes based on phosphoric acid (H3PO4), sulphuric acid (H2SO4) with a fluoride salt; and the Focused Ion Beam (FIB) technique, normally named as Nanolab, was used for the microstructural, chemical and morphological characterization, as well as the confocal laser microscopy technique which also served for roughness measurements. The mechanical response of the anodic layers was evaluated through the using of a scratch tester which showed the critical loads for the coating damages. The characterization results showed that both, concentrations and electrolyte species, clearly influenced the morphological and topographical features, as well as the chemical composition of the anodic layer. By using the FIB was possible to detect nanopores within both the surface and the bulk of the coating. Some of the conditions generated a very special coating morphology which promoted a better osteoblasts adhesion. Contrary to what it was a priory expected, all anodic coatings showed high critical loads for damages during scratch test, despite their high porosity, which could be related with some defects coalescence mechanism that allows dissipating the high stress concentration applied during the test.Postprint (published version

    The Boom of cohabitation in Colombia and in the Andean Region : social and spatial patterns

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    In this chapter we use census microdata to document the rise in cohabitation in Colombia and in the Andean countries of Ecuador, Bolivia, Perú and Venezuela over the last four decades. We use multilevel logistic regression models to examine the effect of individual and contextual variables on cohabitation. We show the individual and contextual effects of social stratification, ethnicity and religion on cohabitation. Cohabitation levels follow a negative gradient with education and vary according to ethnic background. The Bolivian, Ecuadorian and Peruvian censuses reveal that the two largest ethnic groups (i.e. the Quechua and Aymara) have, controlling for other characteristics, the lowest incidence of cohabitation. By contrast, Afro-American populations show the highest levels of cohabitation. The joint use of individual- and contextual-level explanatory variables is sufficient to account for the majority of Bolivia's internal diversity regarding cohabitation, but not sufficient to account for the internal diversity identified in Colombia, Peru or Ecuador. Even after controls, residence in the Andes mountain areas continues to be a factor associated with lower levels of cohabitation. This invites further investigations on how the institutionalization of marriage occurred in the Andes

    Spoken term detection ALBAYZIN 2014 evaluation: overview, systems, results, and discussion

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    The electronic version of this article is the complete one and can be found online at: http://dx.doi.org/10.1186/s13636-015-0063-8Spoken term detection (STD) aims at retrieving data from a speech repository given a textual representation of the search term. Nowadays, it is receiving much interest due to the large volume of multimedia information. STD differs from automatic speech recognition (ASR) in that ASR is interested in all the terms/words that appear in the speech data, whereas STD focuses on a selected list of search terms that must be detected within the speech data. This paper presents the systems submitted to the STD ALBAYZIN 2014 evaluation, held as a part of the ALBAYZIN 2014 evaluation campaign within the context of the IberSPEECH 2014 conference. This is the first STD evaluation that deals with Spanish language. The evaluation consists of retrieving the speech files that contain the search terms, indicating their start and end times within the appropriate speech file, along with a score value that reflects the confidence given to the detection of the search term. The evaluation is conducted on a Spanish spontaneous speech database, which comprises a set of talks from workshops and amounts to about 7 h of speech. We present the database, the evaluation metrics, the systems submitted to the evaluation, the results, and a detailed discussion. Four different research groups took part in the evaluation. Evaluation results show reasonable performance for moderate out-of-vocabulary term rate. This paper compares the systems submitted to the evaluation and makes a deep analysis based on some search term properties (term length, in-vocabulary/out-of-vocabulary terms, single-word/multi-word terms, and in-language/foreign terms).This work has been partly supported by project CMC-V2 (TEC2012-37585-C02-01) from the Spanish Ministry of Economy and Competitiveness. This research was also funded by the European Regional Development Fund, the Galician Regional Government (GRC2014/024, “Consolidation of Research Units: AtlantTIC Project” CN2012/160)

    Nurses' perceptions of aids and obstacles to the provision of optimal end of life care in ICU

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    Contains fulltext : 172380.pdf (publisher's version ) (Open Access

    Processing, characterization and biological testing of porous titanium obtained by space-holder technique

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    The high Young’s modulus of titanium with respect to that one of the bone is the main cause of the stress-shielding phenomenon, which promotes bone resorption around implants. Development of implants with a low Young’s modulus has gained increased importance during the last decade, and the manufacturing of porous titanium is one of the routes to reduce this problem. In this work, porous samples of commercially pure titanium grade IV obtained by powder metallurgy with ammonium bicarbonate (NH4HCO3) as space-holder were studied. Evaluations of porosity and mechanical properties were used to determine the influence of compaction pressure for a fixed NH4HCO3 content. Measurements by ultrasound tests gave Young’s modulus results that were low enough to reduce stress shielding, whilst retaining suitable mechanical strength. Biological tests on porous cp Ti showed good adhesion of osteoblasts inside the pores, which is an indicator of potential improvement of osteointegration.This work was supported by the Ministerio de Ciencia y Tecnologia, MICINN (Spain) through the project Ref. MAT2010-20855. Furthermore, the authors want to thank laboratory technicians J. Pinto and M. Sanchez, and the undergraduate student I. Nieto for their assistance in microstructure characterization and mechanical testing.Torres, Y.; Rodríguez, J.; Arias, S.; Echeverry, M.; Robledo, S.; Amigó Borrás, V.; Pavón, JJ. (2012). Processing, characterization and biological testing of porous titanium obtained by space-holder technique. Journal of Materials Science. 47(18):6565-6576. https://doi.org/10.1007/s10853-012-6586-9S656565764718Brunette DM, Tengvall P, Textor M, Thomsen P (2001) Titanium in medicine: materials science, surface science, engineering, biological responses and medical applications. 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